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1. Atelectasis and Thoracic or abdominalsurgery is an indication for incentive spirometry.

2. The volume of air that the patient inspires when performing incentive spirometry should approximate inspiratory capacity.

3. Retained secretions, Respiratory muscleinsufficiency, Hypoventilation, contribute to

the development of atelectasis.

4. Hypoxemia, Postanesthesia recovery, Acutemyocardial infarction are indications for

oxygen therapy.



5. IPPB is indicated in all of the following

situations,

• inability to clear secretions• atelectasis that does not respond to other

therapies

• short – term ventilation• aerosol delivery when muscle fatigue is

present

6. Increased temperature, patchy markings onCXR, tracheal shift toward the affected area,

elevated diaphragm, are clinical signs of

atelectasis.



7. Maintain normoxia, decrease myocardial

work, provide enriched oxygen environment

for increased metabolic needs associated withsevere trauma, are therapeutic objectives of

oxygen therapy.

8. The optimal patient response to treatmentwith incentive spirometry would be Chest

radiograph is negative for atelectasis.

9. Upper airway edema, Sputum induction,

Postextubation edema, Bypass of the upper

airway, are indications for aerosol therapy.



10. Asthma may be described as either

Intrinsic, or extrinsic.

11. The initial ABG during an acute asthmaticepisode usually describes the acid – base

status as Acute hyperventilation.

12. All of the following therapeutic agents arerecommended for use during acute asthmatic

episodes,

• Albuterol• Epinephrine

• Corticosteroids

• Oxygen



13. A critical cell count in determining

prophylactic treatment as well as monitoring

disease progression in AIDS is : CD414. Pentamidine aerosolization is found helpful

in preventing : Pneumocystis infection

15. All of the following are routinely used in thetreatment of pulmonary infection in AIDS

patients,

• Trimethoprim / sulfamethoxazole• Aerosolized pentamidine

• Glucocorticoids

• Isoniazid



16. The key practice in preventing cross –

contamination in the health care setting is :

Practicing universal precautions

17. Maintain clear CXR , is an appropriate

therapeutic goal for pentamidine aerosoltherapy.

18. Obtaining of sputum samples , Foreignbody aspiration , Assessment of the airway ,

An aid in intubation , are indications for

flexible fiberoptic bronchoscopy.



19. Responsibilities involved in bronchoscopy

assisting include :

• Setup of the scope• Cleaning of the instruments

• Specimen retrieval and preparation for

laboratory studies• Delivery of aerosolized drugs

• Evaluating the patient response



20. Elements of proper sputum induction

include :

• Use of hypertonic saline aerosol• Ultrasonic nebulization

• Good patient effort

• Bronchoalveolar lavage and aspiration

• Oral cavity gargling ( preferably with

hypertonic saline ) before procedure .

21. Obesity , Cor pulmonale , Excessivedaytime Sleepiness , Abnormal heart rhythms

are routinely associated with OSAS .



22. Presence of muscular ventilatory efforts

during apneic period are noted on EMG , are

true of OSAS but not Central Sleep Apnea .23. After physical assessment of a patient

presenting for sleep study , you note jugular

venous distention , significant hypertension ,

and a history of COPD . You also find that the

patient is polycythemic . What problem is

illustrated by this data ? Cor pulmonale .



24. During polysomnography of a person who

has been sleeping for 4 hours , the EEG

tracing abruptly flattens . All other parametersremain unchanged . The technician should :

Carefully reattach the electrode .

25. Indications for the institution of Continuous

Positive Airway Pressure include all of the

following :

> For treatment of Obstructive Sleep Apnea

> To increase FRC

> To treat apnea of prematurity

> As an adjunct in bronchial hygiene .



26. Acceptable objectives for CPAP intervention in

the treatment of Obstructive Sleep Apnea are :

> To reduce the number of sleep apnea episodes> To decrease oxygen desaturation during sleep

> To minimize or prevent cardiac dysrhythmias during

sleep

> To minimize daytime somnolence as reported by patient

> To significantly decrease the incidence of symptoms

including headache , agitation , and loud snoring



27. Alternate treatments for sleep apnea

include :

> Weight reduction> Sleep positioning

> Tongue retaining devices

> Tracheostomy

> Pharmacological intervention

28. Diagnosis of Guillain – Barre syndrome is

supported by : High protein concentration in

the cerebrospinal fluid .



29. Relative contraindications to directed

coughing include all of the following :

> Inability to control possible transmission of infection from the patients suspected or

known to have pathogens transmittable by

droplet nuclei .

> Elevated intracranial pressure or intracranial

aneurysm .

> Reduced coronary artery perfusion , suchas in myocardial infarction .

> Acute head , neck , or spine injury .



30. Indications for postural drainage include :

> Evidence of difficulty mobilizing secretions

> Presence of atelectasis> Presence of foreign body in the airway .

31. Following are true regarding IPPB :

> It may cause pulmonary barotrauma

> It should produce a Vt greater than the

spontaneous one

> It is contraindicated when evidence of

tracheoesophageal fistula is present .



32. Indications for PEP therapy include :

> The need to reduce air trapping in

obstructive disease> The need to mobilize secretions

> The need to reverse atelectasis

33. Following pulmonary data signify an intact

, well – functioning pulmonary system :

> Spontaneous Vt = 7 mL / kg

> Spontaneous VC = 15 mL / kg



34. Laryngotracheobronchitis ( LTB ) is usually Viral

in nature .

35. The usual prodrome for LTB consists of :

> Upper respiratory infection ( URI )

> Low – grade fever

36. The drug of choice for inpatient treatment of LTB

is : Racemic epinephrine

37. LTB would be considered severe when :

> PaCO2 increases with a corresponding drop in pH

> Inspiratory stridor is present> Oxygen saturation <90 percent



38. Perform CPR , Defibrillate @ 200 J , Defibrillate at

200 to 300 J , Defibrillate @ 360 J , Administer lidocaine

, is the correct sequence for treatment of ventricular

fibrillation .

39. Cao2 , Sao2 , Pao2 , Fio2 , is required to calculate

an estimated shunt .

40. Following medications may be administered via

endotracheal tube in an emergency resuscitation:

> Epinephrine

> Atropine

> Lidocaine

> Naloxone



41. Information needed to compute a static compliance are :

> Corrected tidal volume

> Plateau pressure

> PEEP

42. The hemodynamic factor most reflective of left heart

function is : PCWP

43. Following are likely causes of pulmonary edema :

> Ventricular failure

> Pulmonary aspiration

> Near drowning

> Head injury



44. The normal gradient between arterial and end tidal carbondioxide ( Pa-

etCO2 ) is : 4.5 mm Hg

45. The ECG changes associated with myocardial infarction include :

> ST – segment elevation

> Inversion of T waves

> Appearance of Q waves

46. Following are risk factors contributing to coronary artery disease :> Obesity

> Smoking

> Sedentary lifestyle

> Elevated LDLC

47. Creatine kinase , Lactate dehydrogenase , are the enzymes routinely used

in diagnosing and monitoring myocardial infarction .



NORMAL HEMODYNAMIC PRESSURES

1.) Heart rate 60 – 90

2.) systemic BP

Systolic : 90 – 140Diastolic : 60 – 90

3.) Central venous pressure 1 – 6

4.) Pulmonary artery pressure

Systolic : 15 – 25Diastolic : 5 – 15

5.) Pulmonary capillary wedge pressure

5 – 12

6.) Cardiac output 5 – 8 L / min

7.) Arterial partial pressure of oxygen ( Pao2 ) 80 – 100



48. When a patient is on positive pressure ventilation

, he or she may experience the adverse effects of :

> Hyperinflation of the lungs> Gastric irritation

> Decreased transmural heart pressures

> Decreased renal perfusion

49. Current guidelines for reimbursement of home

oxygen include : Presence of Sao2 < 85 %

50. During basic life support delivery , using amanual resuscitator for ventilation , the RCP sees

that the victim’s abdomen becomes markedly

distended . The RCP should recommend :

Endotracheal intubation



51. Signs associated with a tension pneumothorax

include all of the following :

> Absence of breath sounds over the affected area

> Lack of markings on CXR

> Increased inspiratory pressures

> A decrease in dynamic lung compliance

52. The first – line drug for the treatment of

ventricular dysrhythmia in adults is : Lidocaine

53. Urine output is considered within the normal

range if it is : 30 to 50 mL / h



54. Evaluation of proper airway placement includes :

> Auscultation of breath sounds

> Chest X – ray

> Passage of a suction catheter through the tube

> End tidal CO2 measurement

55. All of the following describe the neonatal airway :

> It has a relatively large tongue

> The narrowest part is the cricoid ring

> The epiglottis lies horizontally

> It has a very compliant chest wall



56. When the RCP suctions a nasally intubated

neonate who has a size 3.0-mm endotracheal tube

in place , respiratory distress is noted . To correct

this , the RCP should : Hyperoxygenate before the

procedure

57. The CXR associated with meconium aspirationsyndrome will likely reflect : Hyperinflation

58. To drain an empyema , the chest tube should beinserted in : The 6th or 7th interspace in the midaxillary or

posterior axillary line



59. Following represent suctioning complications in

the neonate :

> Infection

> Atelectasis

> Increased BP

> Bradycardia

> Pneumothorax

60. When a neonate is being resuscitated in the

delivery room and he or she is found to have a heart

rate of 40 bpm without spontaneous respirations ,what should be done ?

> Give chest compressions

> Perform mechanical ventilations



61. Following are limitations to the use of pulse

oximetry :

> Motion artifact

> Low perfusion states

> Skin pigmentation

> Abnormal hemoglobin's

62. Oxygen in the home care setting is indicated

when : Sao2 < 85% in subjects breathing room air

63. Respiratory distress syndrome ( RDS ) isgenerally associated with : Low-birth-weight neonates



64. Fluid status may be evaluated by assessing :

> Urine output

> Blood pressure

> Skin turgor

> Jugular venous distention

65. Measurement of central venous pressure is most

closely reflected by : Right atrial pressure

66. Hypokalemia is detected when :Potassium < 3.5 mEq / L



67. If a patient were to contract a nosocomial

staphylococcal infection , IMPROPER

HANDWASHING is the most likely

transmission route .

68. Respiratory distress may occur whencarboxyhemoglobin levels reach : 5 to 10

percent

69. An absolute contraindication to the use of

postural drainage is : Acute spinal injury



70. Respiratory failure is the ‘’ inability to maintaineither the normal delivery of oxygen to the tissues or

the normal removal of carbondioxide from the

tissues ‘’

71. Acute respiratory failure is identified by a Pao2 < 60

mmHg and / or a PaCo2 > 50 mmHg in otherwise healthyindividuals at sea level .

72. Type 1 ( Hypoxemic ) respiratory failure occurs when

the primary problem is inadequate oxygen delivery .



73. The primary causes of hypoxemia are :

> Ventilation / Perfusion mismatch

> Shunt

> Alveolar hypoventilation

> Perfusion / diffusion impairment

> Decreased inspired oxygen

74. Type 2 ( Hypercapnic ) respiratory failure describes ‘’

bellows failure ‘’ of the lungs resulting in elevated

carbondioxide levels . Hypercapnic respiratoryfailure is also known as Ventilatory failure .



75. The three major disorders responsible for hypercapnic

respiratory failure ( ventilatory failure ) are :

> Decreased ventilatory drive> Respiratory muscle fatigue or failure

> Increased work of breathing

76. The use of PEEP during mechanical ventilationallows the clinician to ‘’ Splint the lung ‘’ in a position

of function by increasing the FRC . An increase in

the FRC opens collapsed alveoli and small

bronchioles , thereby improving Ventilation –

Perfusion ratios .



77. PEEP is defined as the maintenance of positive airway pressure

at the end of expiration .

78. The main goal of PEEP is to achieve a Pao2 of greater than 55 –

60 mmHg with an Fio2 of less than or equal to 60 % while avoiding

significant cardio-vascular sequelae .

79. COPD is a chronic disorder , that limits a patient’s ability to

work and , in severe cases , impairs the activities of daily living .

80. The most prominent symptoms of COPD are ,dyspnea and an

impaired exercise capacity .

81. Rehabilitation :- restoration of the individual to the fullest mental

, emotional , social , and vocational potential of which he (or) she iscapable .



82. Patients with COPD manifest decreased exercise

tolerance . The most important factors thought to

contribute to this limitation are :-

> Alterations in pulmonary mechanics .

> Dysfunction of the respiratory muscles .

> Peripheral muscle dysfunction .

> Abnormal gas exchange .

> Malnutrition .

> Development of dyspnea .> Active smoking .



83. The first heart sound ( S1 ) is created by closure of the Tricuspid

valve and Mitral valve

84. In most respiratory illness , what symptom is present in 80% to

90% of the patients ? Cough85. What is the name for the sensation of difficult or uncomfortable

breathing ? Dyspnea

86. What type of chest pain is characterized by a “ crushing tightness

“ often radiating to the neck , shoulders , and arms ? Anginapectoris

87. Patients who have chronic pulmonary disease with swelling of

the lower extremities may have : Cor pulmonale

88. Bradycardia is a heart rate less than : 60 beats / min



89. What is the normal range of adult blood pressure ? 110 - 130 /

70 - 80 mmHg

90. What is the normal inspiratory – expiratory ratio ( I : E ) of

bronchial breath sounds in adults ? 1 : 1.591. Chest percussion is a useful diagnostic clinical tool in which of

the following entities ? The level of diaphragmatic excursions

92. In which clinical entities would hyperresonance over the thorax

be heard ? Pneumothorax

93. What added lung sound is characterized as high – pitched ,sibilant , or whistling from partial obstruction of airways ? Wheeze

94. Heart sounds heard over the right second intercostal space near

the right sternal border originate from the : Aortic valve



95. According to the 1987 statement of standardization of spirometry by

the ATS , spirometers must meet the following minimal standards formeasuring vital capacity ( VC ) ?

> Accumulate volume for at least 30 seconds

> Be capable of measuring volumes of at least 7 L

> Measure volume independent of flow between 0 and 12 L / sec

> Have an accuracy of at least + or – 3% of reading or 50 mL , whichever is

greater

96. How should the adult patient be positioned when a pulmonary function

test is performed ? Sitting or Standing

97. For forced vital capacity ( FVC ) reproducibility to be present accordingto ATS standards , what criteria must be met ? The best two of at least three

acceptable attempts should be within + or – 5% or 100 mL , whichever is greater



98. In what time period is the maximum voluntary ventilation

( MVV ) maneuver performed ? 12 seconds

99. All actual spirometry values should be converted to : Body

temperature , ambient pressure , saturated with water vapor ( BTPS

)

100. Following methods can be used to determine FRC :

> Helium dilution

> Nitrogen washout

> Body plethysmography

101. What gas law describes how the body plethysmograph

operates ? Boyle’s law 102. What gas analyzer measures concentration by actually

counting the relative number of ionized molecules of each gas? Mass spectrometer



103. What device is used to determine physiologic

dead space ? Douglas bag

104. The respiratory quotient is defined as : CO2 production / O2 consumption

105. What type of oxygen electrode is in arterial blood

gas analyzers ? Polarographic 106. When a blood sample is introduced into a bloodgas analyzer , carbondioxide diffuses across themembrane according to what gas law ? Henry’s law

107. Carboxyhemoglobin and Methemoglobin can bedetermined by spectrophotometry



108. Bronchial breath sounds over lung periphery indicate ?

Pneumonia

109. Flattening of the diaphragms on chest film are generally

consistent with which clinical entity ? Emphysema

110. Elevated serum creatinine is indicative of : Renal disease

111. Which of the following would be the darkest on an X – ray

film ? Air 112. What is a desirable platelet count to prevent spontaneous

bleeding ? > 40,000

113. Hypoalbuminemia and hypoproteinemia may lead to :

Pulmonary edema 114. What technique can be used to visually inspect the airways

? Bronchoscopy



115. What is the advantage of magnetic resonance imaging (

MRI ) over a lateral X – ray film ? Better three – dimensional

perspective

116. What estimate of postoperative forced expiratory volume

in 1 second ( FEV1 ) indicates that pulmonary resection will

usually be tolerated ? > 800 mL

117. An ( FEV1 / FVC ) which is > 73% usually rules out :

Obstructive lung disease 118. Which pulmonary function test should be used to evaluate

the reversibility of small airway diseases ? Pre – and

postbronchodilator spirometry 119. Which agent is used to image pulmonary perfusion ?

Technetium macroaggregated albumin

ll i id d i k f



120. Following are considered risks for surgery ?

> Cigarette smoking

> Old age> Obesity

> Chronic lung disease

121. Which of the following tests evaluates thepatient’s motivation to cooperate following surgery ?

MVV

122. Which tests evaluates the surface area of thealveolar capillary membrane ? DLco

123 Th il i b ll i d f



123. The ventilatory pump is a bellows comprised of

the ribs , bony thorax , and respiratory muscles .

> Contraction of the diaphragm during

inspiration causes an enlargement of the thoracic

cage , producing relatively negative pressures at the

alveolar level . This causes atmospheric air to be

drawn into the alveoli . With expiration thediaphragm relaxes , the thorax becomes smaller ,

and air flows from the alveoli back out into the

atmosphere through the same system of conducting

airways . Ventilation is therefore a to – and – fromovement of air .



124. Motor innervation to the diaphragm occurs via the

phrenic nerve , which is derived from the third through fifthcervical nerves

125. The visceral and parietal pleura join one another at thelung hila

126. The parietal pleura contains abundant pain fibers derivedfrom the intercostal nerves

127. The visceral pleura does not contain pain fibers128. At rest , average intra – pleural pressure is about – 4 cmH2O

129. The upper respiratory tract is primarily designed to purify

, warm , and humidify the air ; it consists of the nose , paranasal

sinuses , pharynx , and larynx



130. Resistance to airflow is higher in the nose than in the mouth because of this

intricate system of baffles ( the nose contains baffles that are bathed by thin ,

watery secretions designed to trap foreign particles and add moisture to the

inspired air ) . This explains mouth breathing during vigorous exercise . In this

case , the valuable air conditioning function of the nose is lost , and dry , cold air may enter the lower airways . In patients with abnormal irritability of the bronchi

, inspiration of cold air through the mouth during exercise may initiate

bronchospasm

131. Normally , there are about 23 generations of airways , of which the first 16 areconducting airways and the last 7 are respiratory airways

132. Hoarseness is an ominous sign in patients with carcinoma of the lung . Other

diseases , such as granulomas , lymphomas , and aortic aneurysms , may also

interrupt the left recurrent laryngeal nerve in the mediastinum

h i i h



Mechanisms in Asthma

1. Triggers : - ( Allergens , Viruses , Bacteria , Fungi , Irritants )

2. Cell Activation : - Antibodies and immune cells activate leukocytes andtissue cells

3. Mediator Release : - Cell activation and subsequent release of cell toxicmediators like ECP ( Eosinophil Cationic Protein ) , EPX ( EosinophilProtein X ) , EPO ( Eosinophil Peroxidase ) , MPO ( Myeloperoxidase )

destroy the epithelium and other tissue . This open up for direct contacts between allergens and other triggers and nerve cells , resulting in directirritation , secretion , leakage , oedema , and bronchoconstriction as wellas formation of new connective tissue

4. Physiological responses : - Oedema , Glandular secretions , Plasma leakage ,

Epithelial permeability , Connective tissue formation , Muscleconstriction , Nerve activation

5. Symptoms : - Wheezing , Shortness of breath , Coughing , Phlegm , Chest -

tightness

P t l D i P iti



Postural Drainage Positions

• Upper Lobes : -

1. ) Apical Segments of both Upper Lobes Sitting Upright

2. ) Posterior Segment of Right Upper Lobe Left side lying

, turned 45 degree towards prone3. ) Posterior Segment of Left Upper Lobe Right side lying

, turned 45 degree towards prone , shoulders raised 30 cm

4. ) Anterior Segments of both Upper Lobes Supine

Middl L b



• Middle Lobe : -

1. ) Lateral and Medial Segments

Supine , quarter turned to left , foot of

bed raised 35 cm

• Lingula : -1. ) Superior and inferior Segments

Supine , quarter turned to right , foot

of bed raised 35 cm

L L b



• Lower Lobe : -

1. ) Apical Segments of both lower lobes Prone , head

turned to side

2. ) Anterior basal Segments of both Lower Lobes Supine, foot of bed raised 45 cm

3. ) Posterior basal Segments of both Lower Lobes Prone ,

head turned to side , foot of bed raised 45 cm

4. ) Medial basal Segment Right side lying , foot of bedraised 45 cm

5. ) Lateral basal segment Left side lying , foot of bed

raised 45 cm

----------------- -----------------

M h i l V til ti



Mechanical Ventilation

• Indications :-

1. ) Severely impaired gas exchange

2. ) Rapid onset of respiratory failure

3. ) An inadequate response to less

invasive medical treatments

4. ) Increased work of breathing withevidence of respiratory muscle fatigue

• Parameters that can help to guide the



• Parameters that can help to guide the

decision as to whether mechanical ventilation

is needed include respiratory rate ( >35 ) ;

vital capacity ( <10-15 ml / kg ) ; PaO2 ( <60

mmHg with FiO2 >60% ) ; PaCO2 ( >50

mmHg with pH <7.35 ) ; and an absent gag (

or ) cough reflex

• Arterial blood gases should be checked 15

minutes after initiation of mechanicalventilation , and settings changed accordingly

• Complications of Mechanical Ventilation :



• Complications of Mechanical Ventilation :-

1. ) Barotrauma has traditionally referred to the

rupture of small airways and alveolar walls by high

pressure

2. ) Volutrauma has been described as pulmonaryedema , diffuse alveolar damage , and epithelial and

microvascular permeability resulting from

overdistention of airspaces rather than actual

rupture

• To minimize lung trauma resulting from



• To minimize lung trauma resulting from

excessive airway and alveolar pressure and

volume , two measurements are noted :

1. ) Plateau pressure ( P plat ) , is

static pressure measured at end inspiration .P plat represents the pressure imposed on

distended alveoli

2. ) Auto-PEEP , is the pressure

remaining in airways and alveoli at the

instant before inspiration



• Auto-PEEP develops when a positive- pressure breath is delivered before complete

exhalation of the previous breath . As a

result , air becomes trapped and pressurewithin the lungs increases . This can lead to

complications such as barotrauma and

pneumothorax

Ventilator ; is an electro mechanical device



• Ventilator ; is an electro-mechanical device ,

that an amount of air is pushed to the

Respiratory system Two forms of therapeutic device may be

used ,

1. ) Positive pressure ventilation

2. ) Negative pressure ventilation

• Positive pressure ventilation :- Delivering positive

pressure to the airway

• Negative pressure ventilation :- Providing

intermittent negative pressure within pleural space /

around the thoracic cage

P i f ti f til t



• Primary function of ventilators :-

1. To facilitate the movement of gas into thelungs

2. To ensure adequate oxygenation

3. To ensure adequate elimination of CO24. To control the rate of alveolar ventilation

5. To increase the lung volume

6. To increase the chest wall compliance

7. To decrease the work of breathing



• As a general rule , the cuff on an endotracheal (

or ) tracheostomy tube should be inflated . The

pressure within the cuff should be the lowest

possible that allows delivery of adequate tidal

volumes and prevents pulmonary aspiration .

Usually the pressure is maintained at lessthan 25 cm H2o to prevent injury and at

more than 20 cm H2o to prevent

aspiration . Cuff pressure must be

monitored at-least every 8 hours

Complications of Intubation



Complications of Intubation

1. Tube malposition

2. Esophageal intubation

3. Significant aspiration

4. Laryngeal damage

5. Pneumothorax

• Tube malposition can be identified shortly after

intubation by auscultation of bilateral axillae

• Causes of Respiratory acidosis :



• Causes of Respiratory acidosis :-

1. COPD

2. Severe asthma3. CNS depression

4. Mechanical under ventilation

5. Neuromuscular disease

• Causes of Respiratory alkalosis :-

1. Asthma

2. Mechanical over ventilation3. Restrictive lung disease

4. Hepatic failure

5. Hypoxemia



• In mechanically ventilated patients ,respiratory acidosis is corrected by anincrease in the minute ventilation ( Vt * RR )

• Oxygenation may be improved by an increase

in FiO2 ( or ) PEEP

• Mean arterial pressure = SBP + 2 ( DBP )

/ ( divided by )

3

= 70 – 105 mm Hg

• The most common complication of



• The most common complication of mechanical ventilation is barotrauma .

High pressure can lead to rupture of thealveolar wall , which in turn can lead topneumomediastinum , pneumothorax ,

pneumoperitoneum , and subcutaneousemphysema . Other common

complications include increased

intracranial pressure , fluid retention , localtrauma to the nares and mouth , tracheal

necrosis , renal failure .

• PEEP ( Positive End Expiratory Pressure ) ; is defined as thei f i i i h d f i i



maintenance of positive airway pressure at the end of expiration . In so

doing , the alveoli fail to collapse and functional residual capacityincreases . The end result is improved ventilation-perfusion matching

in the pulmonary circulation . PEEP is usually set at 2.5 ( or ) 5.0 cm H2o .

It can be applied to the spontaneously breathing patient in the form of CPAP ( or )

to the patient who is receiving mechanical ventilation . The appropriateapplication of PEEP usually increases lung compliance andoxygenation while decreasing the shunt fraction and the work ofbreathing . PEEP is used primarily in patients with hypoxic respiratory

failure ( e.g., ARDS ; Cardiogenic Pulmonary Edema ) . Low levels of PEEP( 3-5 cm H2o ) may also be useful in patients with COPD , to prevent dynamic

airway collapse from occurring during expiration . The main goal of PEEP is toachieve a PaO2 of greater than 55-60 mm Hg with an FiO2 of lessthan ( or ) equal to 60% while avoiding significant cardiovascular sequelae .

Usually , PEEP is applied in 3 to 5 cm H2o increments during monitoring of oxygenation , organ perfusion , and haemodynamic parameters . Patient whoreceive significant levels of PEEP ( i.e., > 10 cm H2o ) should not have their PEEP removed abruptly , because removal can result in collapse of distal lungunits , the worsening of shunt , and potentially life – threatening hypoxemia .

Modes of Ventilation



Modes of Ventilation

1. CMV ( Continuous Mandatory Ventilation or

Controlled Mechanical Ventilation ) :- In this

mode , the rate and tidal volume are controlled

by the machine . All breaths are mandatory

breaths and there is no mechanism for patienttriggering ( if patients can trigger , it becomes

Assist Control ) . CMV is used for patients who

are unconscious ( or ) whose respiratory musclesare paralysed and for those who need their

PaCO2 tightly controlled .

2. In Assist-Control Ventilation , the patient can breath at



, p

his own rate assisted by the machine but in addition ,

the machine delivers a minimum set number of

controlled breaths at the rate set on the machine .3. In Intermittent Mandatory Ventilation ( IMV ) , the

patient is allowed to breath spontaneously with no

machine assistance but the machine delivers a minimum

set rate and tidal volume . The potential danger is that

the timing of machine rate has no correlation to the

inspiratory effort of the patient – so “ stacking “ of

breaths can occur ( the machine could try to force a tidalvolume during a spontaneous exhalation phase ) .

4 In Synchronised Intermittent Mandatory



4. In Synchronised Intermittent Mandatory

Ventilation ( SIMV ) , which is similar to

IMV , breath stacking is sought to beavoided by synchronising the mandatory

breath delivered by the machine to the

patient’s inspiratory effort – i.e. themandatory breath is triggered by the patient .

If no triggering occurs for a specified

duration , the mandatory breath is delivered .

5 Pressure Support :-



5. Pressure Support :-

• Set inspiratory assist pressure• No set tidal volume ( or ) rate

• Patient must be able to initiate breaths , after

which the ventilator delivers a preset airway pressure

• May need to convert to another mode if patient is

sedated and can no longer initiate breaths• Monitor RR , exhaled Vt and patient effort

• Acclimatisation to altitude involves progressive increase in ventilation over days



p g y

and progressive polycythaemia over weeks . Too rapid an ascent to altitude risks

life-threatening pulmonary and cerebral oedema

• The presence of a pneumothorax , recent sub aqua diving ( or ) severe respiratoryfailure are contraindications to commercial aircraft flight

• Pulmonary infections , especially tuberculosis ( or ) pneumocystis carinii may be

the presentation of , as well as a complication of , AIDS

• HIV infection impairs immunity by the slow , steady attrition in CD4+Thlymphocyte numbers . PCP becomes inevitable when CD4-lymphocyte counts

fall below 200 mm3

• In COPD ; the airways obstruction is due principally to loss of airway supports

and small airway fibrosis rather than the potentially more reversible obstructiondue to bronchial inflammation in asthma

• The most relevant , sleep-associated , respiratory



The most relevant , sleep associated , respiratory

changes are the diminution of muscle tone ,

especially during REM sleep . This risks both

respiratory under ventilation and increased upper

airway resistance ( or ) closure .

• Thoracoscopy :- Traditionally , a single , rigid ,

viewing scope with an operating channel is

inserted percutaneously into the pleural space .

Thoracoscopy allows both pleural surfaces to beinspected , biopsies to be taken and insufflation of

a sclerosant for pleurodesis .

Emergency Medications



Emergency Medications

1. Adrenaline

2. Nor-adrenaline

3. Atropine

4. Dopamine

5. Dobutamine

6. Lignocaine

7. Pethidine

8. Morphine9. Aminophylline

• Aminophylline Reversible airways obstruction ; Severe



Aminophylline Reversible airways obstruction ; Severe

acute asthma

• Adrenaline

To treat mucosal congestion of rhinitis and

acute sinusitis ; to relieve bronchial asthmatic paroxysms

• Nor-adrenaline is a vasopressor used in shock

• Atropine Pre-operative medication to inhibit secretionsand salivation

• Lignocaine In treatment of ventricular arrhythmias

• Sibutramine is an orally administered agent for thetreatment of obesity

Antiasthmatics



Antiasthmatics

1. ) Inhalational corticosteroids :

• Beclomethasone inhalers

• Aminophylline

• Levosalbutamol

• Budesonide inhalers

• Formoterol inhalers

• Fluticasone inhalers

2. ) Systemic corticosteroids :

• Prednisolone



Antiarrhythmics1. Lignocaine

2. Digoxin

3. Propranolol

4. Amiodarone

5. Adenosine



Antihypertensives

1. Reserpine

2. Propranolol

3. Sodium Nitroprusside

4. Hydralazine



Antivirals1. Amantadine

2. Ribavirin

3. Interferon-Alpha

4. Acyclovir



Antifungals1. Amphotericin-B

2. Fluconazole

3. Griseofulvin



Anti-infective Drugs1. Providone Iodine

2. Chloramphenicol

3. Sulfonamides

4. Nystatin



Antihistamines ( Non-Sedative )

1. Levocetirizine

2. Astemizole

3. Terfenadine4. Loratadine

5. Cetirizine



Anti-tussives

• are used for suppression of cough

• are used mainly for unproductive dry cough and if

the cough is hazardous . ( e.g. Cardiac disease ,Hernia , Ocular surgery )

• The principal antitussives are Codeine ,Dextromethorphan , Oxolamine , Morphine



Retreatment Agents ( for MDR-TB )

1. Capreomycin

2. Ethionamide

3. Kanamycin

Neuromuscular Drugs

1. Succinyl choline2. Pancuronium



Expectorants

• are drugs which reduce viscosity of bronchialsecretion , hence the removal is facilitated by coughing

• E.g. :- Potassium iodide , Ammonium chloride ,Potassium and Sodium citrate , Vasaka , Balsum of Tolu

Oxygen delivery techniques



yg y q

1. ) Nasal cannula :-

Flow rate ( L / min ) :- 1 - 6 Conc. delivered ( % ) :- 24 – 44

Other :- Inspired O2 conc. depends on flow rate andpatient’s tidal volume

2. ) Simple face mask :-

Flow rate ( L / min ) :- 6 – 10

Conc. delivered ( % ) :- 35 – 60

Other :- May promote CO2 retention at lower flow rates

3. ) Venturi mask :-



Flow rate :- 2 – 12 lts / min

Conc. delivered :- 24 – 60 %

Other :- Accurately controls proportion of inspiredO2 . Use in patient’s with chronic hypercarbia ( i.e., COPD )

4. ) Face mask with O2 reservoir :-

Flow rate :- 12 – 15 lts / min Conc. delivered :- 60 – 90 %

Other :- Provides high inspired O2 concentration

5. ) Bag – Valve – mask :-

Flow rate :- 15 lts / min

Conc. delivered :- 100 %

Provides the highest inspired O2 concentration

Spirometry



Spirometry• Spirometry is a precise diagnostic test used to determine the condition of

a patient’s lungs

• An instrument called a spirometer quickly and accurately measures theflow rate ( speed of air ) and the volume ( amount ) of air exhaled by thepatient while performing a standardized maneuver

• A spirometer can assist a physician in early diagnosis and detection of pulmonary disease . Once treatment has begun , a spirometer can

determine the response to therapy and document the course of the disease• Spirometry is often performed as a screening procedure

• Spirometry is recommended as the “ gold standard “ for diagnosis of obstructive lung disease

• Behavior modification such as smoking cessation can be reinforced by

spirometry

• Spirometry is a reimbursable test both by Medicare and third party

carriers

• Spirometry is a patient dependent test . If the patient does not do the

maneuver properly the results are not meaningful



maneuver properly the results are not meaningful

• The flow / volume curve is more sensitive than the volume / time curve .

In addition , when an inspiratory breath is included in the FVC maneuver ,a complete flow / volume loop can be generated

• The purpose of the curve is to confirm that the test was done correctly

and that the patient gave their best effort

• The patient’s effort is compared to a set of normal values ( or ) predicted

values based on the age , height , sex and race of the patient

• The inability to reach the normal level of volume could indicate the

possibility of restriction ( or ) restrictive lung disease

• If the flow rate is less than normal it could be an indication of obstruction

( or ) obstructive lung disease

• The American Thoracic Society suggests that individuals

meeting any one of the following criteria should have at



meeting any one of the following criteria should have at

least one spirometry test performed annually :

1. Smokers over 40 years old2. History of shortness of breath upon exertion ( or ) at rest

3. History of chronic cough ( or ) sputum production

4. History of wheezing ( or ) chest tightness

5. History of frequent “ colds “ ( or ) allergic rhinitis

6. Occupational exposure to inhaled dust ( or ) chemicals

7. All patient’s with asthma , bronchitis and other lung diseases

8. All patient’s on bronchodilator

9. Pre-operatively for all patient’s scheduled for thoracic ( or ) upper

abdominal surgery

Restrictive Defects



• This category of disease includes chest wall dysfunction , neurologic

diseases resulting in paralysis of the muscles of inspiration , dysfunction

of the diaphragm , absent lung tissue , and scarring of the lungs as withinterstitial lung disease .

• Atelectasis and obesity are two of the more common causes of a

restrictive lung defect .

• “ Atelectasis “ , is caused by persistent ventilation with small tidal

volumes ( or ) by resorption of gas distal to obstructed airways .

• Patient’s who have undergone upper abdominal ( or ) thoracic surgery

are at the greatest risk for atelectasis .

• Lung expansion therapy ( Incentive Spirometry Sustained , maximal

inspiration ) corrects atelectasis by increasing the transpulmonary

pressure gradient . This can be accomplished by deep spontaneous

breaths ( or ) by the application of positive pressure .

• The most common problem associated with lung expansion therapy is

the onset of respiratory alkalosis , which occurs when the patient breathes

too fast .

Combined Defects



• Certain diseases can result in both obstructive

and restrictive defects . Two examples are ,i. ) Sarcoidosis

ii. ) Severe emphysema

i. ) Sarcoidosis , in its final stages severely reducesvolume and limits airflow .

ii. ) Severe emphysema , which results in obstruction

to airflow out of the lungs . Thus the residual

volume gas in the lung slowly increases andeventually restricts the volume of air that can be

inspired . The net result is a combined obstructive

and restrictive defect .

Vital Capacity



• Both restrictive and obstructive diseases can decrease VC .

i. ) Restrictive lung disorders reduce FVC by shrinking thelung .

ii. ) Obstructive lung dysfunction , causes a decrease in the

FVC by causing a slow rise in the RV .

• A slow exhalation may allow more air to be exhaled from the

lung because , a slow exhalation helps reduce air trapping .

In some patient’s , forceful exhalation causes airways to

close prematurely because of the high intrathoracicpressures produced . This early closure may spuriously

decrease the measured VC volume as gas is trapped distal

to the airway closure and cannot be exhaled .

• Vital capacity is an important pre-operative

t f t Si ifi t d ti i VC ( l



assessment factor . Significant reduction in VC ( less

than 20 ml / kg of ideal body weight ) indicates that

the patient is at a high risk for post-operativerespiratory complications . This is because VC

reflects the patient’s ability to take a deep breath , to

cough , and to clear the airways of excess

secretions .

• VC is also useful in evaluating the patient’s need for

mechanical ventilation . A vital capacity of less than15 ml / kg indicates that the adult patient’s

ventilatory reserve is decreased significantly .

Closed-system Helium Dilution Method



• Helium is used because , it is an inert gas and is not significantly

absorbed from the lungs by the blood .

• This test is based on the principle that if a known volume andconcentration of helium are added to the patient’s respiratory system , the

helium will be diluted in proportion to the size of the lung volume to which

it is added .

• Helium is breathed at Vt , while oxygen is added to replace the oxygen

that is consumed by the patient during the test .

• The CO2 must be absorbed out of the closed system to prevent an

increase in the dilutional effect on the helium and a falsely enlarged FRC

measurement .

• If leaks occur with this method , the measured volumes will be

overestimated . Other factors influencing the quality of the test include ; 1.

) the blower speed of the device . 2. ) how soon the technician stops the

test after equilibrium is achieved . 3. ) the ventilatory pattern of the patient

being tested . 4. ) if parts of the lung communicate poorly with the

atmosphere , the results will be inaccurate .

• The use of helium in laryngeal ( or ) tracheal obstruction , is

based on the relationship of breathing energy to gas density



based on the relationship of breathing energy to gas density .

If obstruction is significant and the work of breathing air ( or )

oxygen is very high , mixtures of helium and oxygen may be

respired with less effort .

• Helium is an inert gas with limited medical applications ; its

widest use is probably in deep diving . Helium is usually

mixed with 20% oxygen for this purpose to replace nitrogen .

• Among its advantages are low density ( one seventh that of

nitrogen ) , which allows easier breathing of the mixture

under hyperbaric conditions , and lower solubility in tissuelipids than nitrogen ( one third ) . The result is less stress in

breathing , with reduced decompression sickness and

decompression time .

Clinical features of hypoxaemia



1. Cyanosis

2. Tachypnoea

3. Tachycardia arrhythmias / bradycardia

4. Peripheral vasoconstriction

5. Respiratory muscle weakness

6. Restlessness Confusion Coma .

Clinical features of hypercapnia1. Flapping tremor of hands

2. Sweating

3. Tachypnoea

4. Tachycardia Bradycardia5. Peripheral vasodilation leading to warm hands and headache

6. Respiratory muscle weakness

7. Drowsiness Hallucinations Coma .

Diffusion Capacity



• The ability of gas to diffuse across the alveolar-capillary

membrane can be measured .

• The determinants of gas exchange across the membrane

include the following :-

1. ) Diffusion coefficient of the gas used in testing .

2. ) Surface area of the membrane .

3. ) Thickness of the membrane .

4. ) Blood volume and flow in the pulmonary capillary

tree .

5. ) Distribution of the inspired gas .6. ) Hematocrit ( is the ratio of red cell volume to that of

whole blood ) .

• Diffusion , is measured by using carbon-monoxide at minute

levels ( 0 4% )



levels ( 0.4% ) .

• Because of carbon-monoxide’s intensive affinity for

hemoglobin ( over 200 times greater binding power to

hemoglobin than oxygen ) , the ability of carbon-monoxide to

diffuse is limited by the membrane and not by capillary blood

flow . It is therefore , a diffusion-limited gas rather than a

perfusion-limited gas .

-----------*---------*--------*---------*---------*----------*--------*---------

• Obesity is a multifactorial disorder of energy balance in which

chronic calorie intake is greater than energy output .

• Obesity hinders movement of the diaphragm and increases

the work of breathing ( making inspiration more difficult ) .

• The main treatment of obesity is a suitable diet and increased

exercise . There are , at present only two drugs licensed for

the treatment of obesity , Sibutramine and Orlistat .

Disorders of the Neuromuscular Junction



1. Myasthenia gravis

2. Lambert-Eaton syndrome

3. Poisoning ( Organophosphate , Tetanus , Botulism )

Disorders of the Nerves1. Guillain-Barre syndrome

2. Phrenic Nerve damage and Diaphragmatic Paralysis

Disorders of the Spinal Cord1. Amyotrophic Lateral Sclerosis

2. Poliomyelitis

Disorders of the Brain

1. Stroke

Disorders of the Thoracic Cage



1. Kyphoscoliosis

2. Flail Chest

3. Ankylosing Spondylitis

Lower Respiratory Tract Infections1. Pneumonia

2. Lung abscess

3. Tuberculosis

Neonatal Cardio-pulmonary Disorders1. Respiratory distress syndrome

2. Bronchopulmonary dysplasia

3. Meconium aspiration

Airway Disorders of the Pediatric Patient



1. Epiglottitis

2. Laryngotracheobronchitis ( Croup )

3. Bronchiolitis4. Cystic Fibrosis

5. Foreign Body Aspiration

Chronic Obstructive Pulmonary Disease1. Emphysema

2. Chronic bronchitis

3. Asthma

4. Cystic Fibrosis

5. Bronchiectasis

• Forced Vital Capacity :- is the maximum volume of

th t b i d h th ti t h l



gas that can be expired when the patient exhales

as forcefully and rapidly as possible after a

maximal inspiration .• Criteria for Acceptability – FVC maneuver :-

1. Maximal effort ; no cough ( or ) glottic closure during the

first second ; no leaks ( or ) obstruction of the mouthpiece .2. Good start-of-test ; back-extrapolated volume less than 5%

of FVC ( or ) 150 ml

3. Tracing shows 6 seconds of exhalation ( or ) an obvious

plateau ; no early termination ( or ) cutoff .4. Three acceptable spirograms obtained ; two largest FVC

values within 200 ml ; two largest FEV1 values within 200

ml .

• Look at the FEV1 / FVC ratio first if



obstruction is suspected . If the FEV1 / FVC

ratio is lower than expected , obstruction is present . If the ratio is normal ( or ) elevated

, check the percent predicted for FVC and

FEV1 . If FVC and FEV1 are both reducedcompared with the expected values , and

FEV1 / FVC is normal ( or ) high ,

restriction may be present .

• The term “ air trapping “ is sometimes used to describe an increase

in FRC and RV .



in FRC and RV .

• The term “ hyperinflation “ is used to describe the absolute increase

in TLC .

• Total Lung Capacity ( TLC ) is an important diagnostic tool in both

obstructive and restrictive lung diseases . In restriction , the TLC is

usually less than 80% of the predicted value . In obstruction , the

TLC is either normal ( or ) increased ( hyperinflation ) .

• FRC values greater than approximately 120% of predicted values

represent air trapping .

• FRC , RV , and TLC are typically decreased in restrictive diseases .

• Bronchial challenge testing is used to identify and characterize airway

hyperresponsiveness .



yp p

• Challenge tests are performed in patients with symptoms of bronchospasm who have normal pulmonary function studies .

• Bronchial challenge tests are sometimes used to screen individuals whomay be at risk from environmental ( or ) occupational exposure to toxins .

• Several commonly used provocative agents can be used to assess airway hyperreactivity . These include the following :

1. ) Methacholine challenge

2. ) Histamine challenge

3. ) Eucapnic voluntary hyperventilation

4. ) Exercise

• Methacholine is a chemical that increases parasympathetic tone in

bronchial smooth muscle . Histamine triggers a similar responseproducing bronchoconstriction .

• Hyperventilation , either at rest ( or ) during exercise , results in heat

and water loss from the airway . This provokes bronchospasm in

susceptible patients .

• If FEV1 / FVC ratio is greater than 70% and FEV1 is also greater than 70% ; we should

do Bronchoprovocation test .



• Patients to be tested should be asymptomatic , with no coughing ( or ) obvious wheezing .

Their baseline FEV1 should be greater than 70% of their expected value .

• If the patient has an FEV1 less than 1.0 to 1.5 L , there is a risk that a large drop in FEV1

following methacholine challenge might leave the individual with compromised lungfunction .

• Bronchial challenge by inhalation of methacholine is performed by having the patient

inhale increasing doses of the drug . Most clinicians consider the test positive when

inhalation of methacholine precipitates a 20% decrease in FEV1 . The methacholine

concentration at which this 20% decrease occurs is called the Provocative Concentration (

or ) PC20% .

• Patients who truly have asthma usually display a 20% decrease in FEV1 . The lower the

dose of methacholine , the more sensitive , ( or ) hyperresponsive , the patient’s airways

are .

• If FEV1 decreases 20% after the diluent ( or ) the first dose of methacholine , PC20 should

be reported as less than the lowest concentration administered . If FEV1 does not decrease by at least 20% after the highest dose , PC20 should be reported as “ greater than 16

mg/ml “ .

• Some patients whose FEV1 drops 20% ( or ) more at low doses of

methacholine may not have asthma . Hyperreactive airways are also



e ac o e ay o ave as a . ype eac ve a ways a e a so

found in some patients with COPD who smoke ( or ) in patients

who have allergic rhinitis .

• A negative methacholine challenge ( i.e., a decrease in FEV1 <

20% at the highest dose ) may occur in patients who have asthma

that has been suppressed by anti-inflammatory medications .

• Some asthmatics may have their asthma triggered by exposure to a

specific agent such as cold dry air .

--*-----*-----*-----*-----*-----*-----*-----*-----*-----*--

• When the PaCO2 is chronically above 50 mmHg the respiratory

center becomes relatively insensitive to CO2 as a respiratory



y p y

stimulant , leaving hypoxemia as the major drive for respiration .

Oxygen administration may remove the stimulus of hypoxemia ,

and the patient develops “ Carbondioxide narcosis “ unless thesituation is quickly reversed . Therefore , oxygen is only

administered with extreme caution .

• Certain infections , such as Mycobacterium tuberculosis ; atypical

tuberculosis ; Pneumocystis carinii ; histoplasmosis ; andmycoplasma ; are readily diagnosed by Broncho Alveolar Lavage .

• Moraxella Catarrhalis is being increasingly recognized as acause of bacterial pneumonia , especially in the elderly . It is

the second most common bacterial cause of acute exacerbationof COPD .

Indications for Flexible Bronchoscopy



1. Diagnostic :- Lung Cancer

Positive Sputum Cytology

Paralyzed Vocal Cord

Unexplained Pleural Effusion

Hemoptysis

Cough Diffuse interstitial infiltrates

Immuno Compromised patient with Pulmonary infiltrates

Ventilator-associated Pneumonia

Endotracheal tube position / patency

Atelectasis

Tracheal esophageal fistula

Acute inhalation injury

Bronchography

2. Therapeutic :-

M l



Mucous plugs

Foreign body removal

Difficult intubation

Stent placement

Balloon dilation

Laser ablation

Brachy therapy

Acute lobar collapse

Electrocautery

Hemoptysis

-----*----------*----------*----------*----------*----------*-----

• Sleep a period of rest for the body and mind , during which volition and

consciousness are in abeyance and bodily functions are partially



suspended ; also described as a behavioral state , with characteristic

immobile posture and diminished but readily reversible sensitivity to

external stimuli .

• Snore rough , noisy breathing during sleep , due to vibration of the

Uvula and Soft palate .

• Sleep is regulated by the reticular formation .

• Epilepsy , brain tumor , brain abscess , cerebral trauma , subdural

hematoma , meningitis , encephalitis , cerebral vascular accident , andcongenital defects of the brain represent types of conditions in which

electroencephalography is useful .

• The electroencephalogram is widely used as a guide in surgery of the

epileptic .

• German psychiatrist Hans Berger , introduced the term

electroencephalogram ( EEG ) to denote the record of the variations in

brain potential . The interpretation of the EEG depends on the frequency ,

amplitude , form , and distribution of the wave activity present .

• Sleep Disorders :-



1. Insomnia :- It can be relieved temporarily by “ Sleeping Pills “ , especially

benzodiazepines , but prolonged use of any of these pills is unwise .

2. Sleep-walking ( Somnambulism ) :- Episodes of sleep-walking are morecommon in children than in adults and occur predominantly in males . They

may last several minutes . Somnambulists walk with their eyes open and avoid

obstacles , but when awakened they cannot recall the episodes .

3. Bed-wetting ( nocturnal enuresis ) .

4. Narcolepsy :- is a disease in which there is episodic sudden loss of muscletone and an eventually irresistible urge to sleep during daytime activities .

5. Sleep apnea :- is caused by obstruction of the airway during inspiration . This

can occur at any age and is produced when the pharyngeal muscles relax

during sleep . In some cases , failure of the genioglossus muscles to contract

during inspiration contributes to the blockage , these muscles pull the tongue

forward , and when they do not contract the tongue falls back and obstructs theairway . The symptoms are loud snoring , morning headaches , fatigue , and

daytime sleepiness . When severe and prolonged , the condition apparently

causes hypertension and its complications . Sleep apnea can be relieved by

teaching subjects not to sleep on their backs , by avoidance of respiratory

depressants such as hypnotics and alcohol , and , in more severe cases , by

positive airway pressure during sleep .

• NREMs ( non-rapid eye movement sleep ) :- the deep ,

dreamless period of sleep during which the brain



dreamless period of sleep during which the brain

waves are slow and of high voltage , and autonomic

activities , such as heart rate and blood pressure ,are low and regular . ( or ) Slow-wave sleep :- four

stages of progressively deepening sleep ( i.e., it

becomes harder to wake the subject ) .

• REMs :- the period of sleep during which the brain

waves are fast and of low voltage , and autonomic

activities , such as heart rate and respiration , areirregular . This type of sleep is associated with

dreaming , mild involuntary muscle jerks , and rapid

eye movements ( REM ) .

• Distribution of sleep stages :- In a typical

i ht f l d lt fi t t



night of sleep , a young adult first entersNREM sleep , passes through stages 1 and 2 ,

and spends 70-100 minutes in stages 3 and 4 .Sleep then lightens , and an REM periodfollows . This cycle is repeated at intervals of

about 90 minutes throughout the night . Thecycles are similar , though there is less stage 3and 4 sleep and more REM sleep toward

morning . Thus , there are Four to Six REMperiods per night .

• Sleep apnea , is defined as a cessation of airflow for at least 10

seconds , which occurs during sleep .



• Obstructive apnea occurs , when respiratory effort is present

but the upper airway is so occluded that no air enters thelungs .

• Central apnea , is characterized by the absence of respiratory

effort .

• OSA is thought to occur because of an upper airway occlusionduring sleep . This occlusion may be caused by several factors, including micrognathia ( small lower jaw ) , large tongue , large

tonsils , retrognathia ( underdevelopment of the mandible ) anddeviated septum . Although the exact mechanism remains

unclear , it is clear that the most common site of theobstruction is in the pharynx .

• Pathophysiology ( OSA ) :- During sleep , the tissues in the

upper airway relax to levels not seen during the waking state .



pp y g g As the airway becomes occluded there is a tremendousincrease in upper airway resistance . In response to the

occlusion , the inspiratory muscles contract more forcefully and cause an increased negative intrathoracic pressure toovercome the obstruction . This is analogous to breathingthrough a wet soda straw . As you try to pull air through the

straw , it actually closes more tightly . The upper airway obstruction may cause apnea , hypercarbia , and hypoxemia .The events eventually rouse the patient to a lighter stage of sleep ( or ) wakefulness , and muscle tone returns to theupper airway . Breathing resumes and the patient’s bloodgases return to baseline levels . As the patient returns to adeeper stage of sleep the process starts again . Thus , thepatient with OSA may cycle between deeper and lighter stagesof sleep several hundred times each night .

• The Multiple Sleep Latency Testing , is ali bl d lid t t d t



reliable and valid test used to assess

objective daytime sleepiness . Thepatient who consistently falls asleep inless than 8 minutes during a daytime

nap is suffering from a sleep disorderthat needs immediate attention . If patient’s fall asleep quickly ( within 8

minutes ) and enter REM sleep in lessthan 15 minutes , this is highly suggestive of narcolepsy .

1. Montelukast :- a leukotriene antagonist used as an antiasthmatic in the

prophylaxis and chronic treatment of asthma .

2 Mid l b di i t ili d th l t t



2. Midazolam :- a benzodiazepine tranquilizer , used as the maleate ester

for sedation and in the induction of anesthesia .

3. Morphine :- the principal and most active alkaloid of Opium ; used asnarcotic ( inducing drowsiness ( or ) very sleepy ) analgesics ( pain

killing drugs ) .

4. Gentamicin :- an antibiotic complex , effective against many gram –

negative bacteria , especially Pseudomonas species .

5. Ribavirin :- a broad – spectrum antiviral used in the treatment of severeviral pneumonia caused by respiratory syncytial virus , particularly in

high - risk infants .

6. Pentamidine :- an anti-infective used as the isethionate salt and effective

against Pneumocystis carinii .

7. Amiodarone :- a potassium channel blocker used in the treatment of Ventricular arrhythmias .

8. Above and beside the vocal cords is a pair of Vestibular folds , usually called

False Vocal Cords . The True vocal cords are held in place and regulated by a

pair of Arytenoid , Cuneiform and Corniculate Cartilages .

• Bronchial Hygiene Therapy , involves the use of

non invasive airway clearance techniques



non-invasive airway clearance techniques

designed to help mobilize and remove secretions

and improve gas exchange . Traditionally , BHTinvolves Postural Drainage , Percussion , and

Vibration ( PDPV ) , combined with cough

training .

• Chest Physical Therapy , involves not only airway

clearance techniques but also various exercise

protocols and breathing retraining methods .

• Cardio Pulmonary Resuscitation :- Aim is to fill the Left

Ventricle with blood .



• Cardiac Arrest :- Causes ;

1. Hypoxia2. Hypotension

3. Hypovolemia

4. Hypokalaemia

5. Electrolyte imbalance

6. Tension Pneumothorax

7. Tamponade

• Defibrillator , should be used only if the patient hasVentricular Fibrillation ( or ) Ventricular Tachycardia . There

is no use of using defibrillator , if the patient has Asystole .

• Terms Commonly Used To Describe Breathing :-

1. Apnea : Absence of spontaneous ventilation



2. Dyspnea : Unpleasant awareness of difficulty breathing

3. Hypopnea : Decreased depth of breathing

4. Eupnea : Normal rate and depth of breathing5. Bradypnea : Less than normal rate of breathing

6. Tachypnea : Rapid rate of breathing

7. Hyperpnea : Increased depth of breathing with ( or ) without an increased rate

8. Hypoventilation : Decreased alveolar ventilation , caused by either a decreased

rate ( or ) decreased depth of breathing ( or ) both9. Hyperventilation : Increased alveolar ventilation caused by either an increased

rate ( or ) increased depth of breathing ( or ) both

10. Orthopnea : Dyspnea in the recumbent position but not in the upright ( or ) semi vertical position

11. Treopnea : Dyspnea in one lateral position but not in the other lateral position

12. Platypnea : Dyspnea caused by upright posture and relieved by a recumbentposition

13. Orthodeoxia : Arterial oxygen desaturation ( hypoxemia ) that is produced by assuming an upright position and relieved by returning to a recumbent position

14. Air hunger : A grave sign indicating the need for immediate transfusion

• Paroxysmal Nocturnal Dyspnea : is the sudden onset of

difficult breathing that occurs when a sleeping



g p g

patient is in the recumbent position . It is often

associated with coughing and is relieved when thepatient assumes an upright position . In patients with

congestive heart failure , PND usually occurs 1 to 2

hours after lying down . In COPD patients , PND

usually occurs on lying down and is often relieved bycoughing and expectorating sputum .

• Chronic Dyspnea : is almost always progressive . It

begins with dyspnea on exertion and overtimeprogresses to dyspnea at rest . COPD , Chronic

Congestive Heart Failure , and severe Anemia are

the most common causes in adults .

• P / F ratio = PO2 / FiO2 = e.g. : 33 / 21%

= 33 / 0 21



= 33 / 0.21

• Maximum Heart Rate for a person duringCardio Pulmonary Exercise Testing should be

220 – age .

• Body Mass Index , can be used to determine

if one’s weight is proportion to one’s height . It

is also valuable for determining health risksand dietary interventions .

• The most prevalent disorders of connective tissues are auto-immune diseases ( diseases in which



antibodies produced by the immune system fail to

distinguish what is foreign from what is self and attack the body’s own tissues )

• Some Auto-immune diseases :-

1. Rheumatoid arthritis2. SLE

3. Myasthenia gravis ( Result :- Progressive

neuromuscular weakness , breathing difficulty )4. Multiple Sclerosis

5. Good pasture’s syndrome ( Result :- Pulmonary

hemorrhage , Kidney failure )

• An acute self-limiting cough is usually due to the Common Cold

• Chronic persistent cough is most commonly caused by postnasal dripsyndrome followed by asthma gastro esophageal reflux chronic



syndrome , followed by asthma , gastro esophageal reflux , chronic bronchitis , bronchiectasis , and other conditions such as left heartfailure , bronchogenic cancer and sarcoidosis .

• In smokers , chronic cough is usually due to chronic bronchitis .

• Appearance of sputum and the possible cause :1. Clear , colorless like egg white Normal

2. Black Smoke ( or ) coal dust inhalation

3. Brownish Cigarette smoker

4. Frothy white ( or ) Pink Pulmonary edema

5. Silicone-like casts Bronchial asthma

6. Yellow ( or ) green , copious Pseudomonas pneumonia , advanced

chronic bronchitis , bronchiectasis ( separates into layers )7. Foul odor ( fetid ) Lung abscess , Bronchiectasis

8. Blood streaked ( or ) hemoptysis Bronchogenic carcinoma ,

Tuberculosis , coagulopathy

• What is the maximum depth that the standard adult bronchoscope can visualize in most patients ? Sixth-level bronchi

• For what purpose are lasers used during bronchoscopy ? To obliterate



• For what purpose are lasers used during bronchoscopy ? To obliterate

obstructing tumors

• What is the most common indication for the use of a bronchoscope ? To

help diagnose abnormalities seen on chest X-ray

• For what condition is the rigid bronchoscope most likely to be used ?

Massive hemoptysis

• Why is the patient undergoing bronchoscopy who develops hypoxemia

less likely to demonstrate arrhythmias ? Use of Xylocaine before theprocedure

• The respiratory therapist assisting the pulmonologist during a bronchoscopy should have medication cups of Xylocaine , normal saline ,

and epinephrine ( Adrenaline : Use Cardiac arrest ) ready before beginning

the procedure • What is the most common sign of Xylocaine overdose during

bronchoscopy ? Seizures

• Stable vital signs ; no bleeding present ; and gag reflex present are mostimportant criteria before discharge of the patient after bronchoscopy

• Intermittent absence of respiratory effort , is the key concept related to the

definition of Central Sleep Apnea



• Relaxation of the upper airway muscles ; tremendous increase in upper

airway resistance ; more forceful contraction of the inspiratory muscles ; is

believed to be responsible for the onset of Obstructive Sleep Apnea

• Enlarged tonsils and adenoids ; is most likely to cause

Obstructive Sleep Apnea in children

• More than 40 apneas per hour of sleep , is the criterion

for severe Sleep Apnea

• Normal body temperature ( euthermia ) varies between 97* and 99.5* F (

36* and 37.5* C ) orally . Fever ( hyperthermia , pyrexia ) is an elevation

of body temperature above the normal range . Pulmonary infections ,

including lung abscess , empyema ( infection within the pleural

space ) , tuberculosis , and pneumonia are all accompanied by fever

• Early morning headache may be the first indication that the patient is

retaining abnormally high amounts of carbon dioxide

• Pursed Lips Breathing exercise is to delay the airway closure in

COPD patient’s



• Gold standard for the diagnosis of COPD is Spirometry

• High pressure alarms in ventilators are due to bronchospasm ;

increased secretions ; and cough

• Low pressure alarms are due to disconnection ( or ) leak in the

tubing's and inadequate cuff pressure

• Long Term Oxygen Therapy is most useful for COPD and

Central Sleep Apnea patient’s

• Collapse :- a state of extreme prostration ( exhaustion ) and

depression , with failure of circulation

• Prednisone :- used as an anti-inflammatory and

immunosuppressant

• Creatinine :- measurements of its rate of urinary excretion are

used as diagnostic indicators of kidney function and muscle

mass

• Idiopathic Pulmonary Fibrosis :- Chronic inflammation and

progressive fibrosis of the pulmonary alveolar walls ; with

i d d t ti ll f t l l k f (



progressive dyspnea and potentially fatal lack of oxygen (

or ) right heart failure . The acute form is called Hamman-

rich syndrome• Pulmonary Tuberculosis :- infection of the lungs by

Mycobacterium tuberculosis , with tuberculous pneumonia ,

formation of tuberculous granulation tissue , caseous

necrosis , calcification and cavity formation . Symptomsinclude ;

1. Weight loss

2. Fatigue

3. Night sweats4. Purulent sputum

5. Hemoptysis

6. Chest pain

• Interstitial Lung Disease :- Diseases that affect the supporting

structures of the lung rather than the airspaces are covered by theumbrella term “ ILD “ Inflammatory changes lead to alveolitis which may



umbrella term ILD . Inflammatory changes lead to alveolitis , which may

resolve ( or ) progress to patchy fibrosis , thickened alveolar septa , remodeling

of parenchyma and shrunken , stiff lungs . Smoking augments the damage .

Involvement of alveoli means involvement of capillaries , and the term “

Collagen Vascular Disease “ can overlap with ILD .

• The two main effects are :

1. Increased lung stiffness , which increases the work of breathing

2. Decreased surface area of the alveolar-capillary membrane , whichimpairs gas exchange

• Fibrosing alveolitis is the commonest ILD

• Pneumoconiosis

• SLE

• Scleroderma

• Sarcoidosis

• Rheumatoid disease

• A chest drainage system is an extension of the patient’s pleural

space



• The anterior chest ( second interspace in the mid clavicular line )

is used for draining a pneumothorax ; the axillary area ( 4th ,

5th or 6th costal interspace in the mid-axillary line ) is used for fluiddrainage

• The mediastinum is the extra pleural space of the thorax . It is

bounded by the ; i. ) lungs laterally ii. ) chest wall anteriorly iii.

) paraspinous gutters posteriorly iv. ) thoracic inlet superiorlyv. ) diaphragm inferiorly

• Thoracentesis is the basic pleural investigation in all conditions

associated with significant pleural effusion . Thoracentesis is

a mandatory diagnostic step , if imaging findings show thepresence of accessible pleural fluid collections . The main

complications of thoracentesis is pneumothorax

• Medical thoracoscopy was introduced into diagnosis of diseases of the chest by Jacobaeus in Sweden .

Th ld t d d t h i f th di i



Thoracoscopy :- gold-standard technique for the diagnosis

of pleural disease . Thoracoscopy allows visualization of

most intrathoracic structures . Therefore , apart from pleural

effusion , the classical spectrum of indications also includes

interstitial lung disease , pneumothorax and localized disease of the

lung , chest wall and diaphragm , as well as mediastinal lesions .

Thoracoscopy also provides considerable managementadvantages both in effusion and in pneumothorax because it

ensures optimal visual placement of drains . In addition it may be

used for therapeutic interventions such as pleurodesis in malignant

effusion and pneumothorax

• Blood supply to and from the lungs can be divided into twocomponents bronchial circulation and pulmonary circulation

i ) A t i l bl d fl i th h th b hi l i l ti i



i. ) Arterial blood flowing through the bronchial circulation is

supplied by the aorta . Bronchial circulation is but one

component of the total systemic circulation , and it serves tomeet the metabolic demands of the lung tissue . Bronchial

circulation supplies blood to and from the entire tracheo-

bronchial tree to the level of the terminal bronchioles

ii. ) The pulmonary circulation begins in the right ventricle andends in the left atrium , and supplies blood to the

respiratory bronchioles , alveolar ducts and alveoli . Blood

flow through the pulmonary circulation allows gas exchange to

occur . The pulmonary circulation is a high-flow and low- pressure circuit

• During inspiration , the diaphragm contracts and the lung

expands as a result of pressure in the pleural space

becoming increasingly sub atmospheric The pressure gradient



becoming increasingly sub atmospheric . The pressure gradient

created between the airway opening of the mouth and alveoli

causes air from the atmosphere to fill the lungs • Discontinuous adventitious lung sounds ( e.g., Crackles ) are

produced by the sudden opening of collapsed airways ( or )

by the movement of air through excessive airway secretions .

Crackles are present predominantly during the inspiratoryphase , while continuous sounds , ( e.g., wheeze ) , are heard

more commonly during exhalation

• A Lung abscess is a cavitated , infected , necrotic lesion of the

lung parenchyma . Most lung abscesses are secondary toaspiration of oropharyngeal secretions . It is important to exclude

malignancy ( or ) other cause of endobronchial obstruction ,

so bronchoscopy is usually necessary

• Summary of the control of oxygen and CO2 content in the blood

:-

1 ) O i t k i t th l d i i i ti d CO2 i ll d



1. ) Oxygen is taken into the lungs during inspiration , and CO2 is expelledduring expiration 2. ) Oxygen diffuses through the alveolar membrane

into the blood , and CO2 diffuses from the blood into the lumen of thealveolus 3. ) Oxygen rich blood passes from the lungs to the heart andfrom the heart to the body cells 4. ) Oxygen diffuses from the blood intothe body cells , and CO2 diffuses from the body cells into the blood 5. )

Blood poor in oxygen and rich in CO2 passes from body cells to theheart , and then to the lungs 6. ) Increased CO2 in the blood stimulates

chemo receptors in the heart ( aortic bodies ) and in blood vessels ( carotid

bodies ) 7. ) Carotid and aortic bodies send nerve impulses to the respiratory

center in the brain stem 8. ) The respiratory center in the brain stem sends

impulses to the diaphragm , internal intercostal muscles , and heart 9. )

Impulses to diaphragm and intercostal muscles increase respiratory rate to

excrete excess CO2 10. ) Impulses to heart increase heart rate , which pumpsmore blood to the lungs in order to eliminate excess carbon dioxide

• Finger Clubbing :- loss of the nail-fold angle to bulbous expansion of the finger-tip



• Causes of clubbing :-

1. Carcinoma of the bronchus

2. Lymphomas

3. Leukemia

4. Pulmonary fibrosis

5. Empyema

6. Lung abscess

7. Bronchiectasis ( including Cystic fibrosis )

8. Chronic tuberculosis

9. Liver disease ( Cirrhosis )

• Very sudden dyspnoea is rare and usually associated withsevere disease e.g., Pneumothorax ; Pulmonary embolism ; Left

ventricular failure ( or ) sudden asthma

• Causes of Haemoptysis :-1. Bronchial Carcinoma



2. Tuberculosis

3. Bronchiectasis4. Lung abscess

5. Pulmonary infarction

• Blue discoloration , termed “ Cyanosis “ , is usually due to increased circulating desaturated hemoglobin

• In COPD :-

1. Hyper-expanded chest with intercostal recession of COPD

2. Flat diaphragm

3. Horizontal ribs

• Broncho Alveolar Lavage :- is a minimally invasive bronchoscopic

procedure used to sample material from the terminal airways and thealveolar spaces



p

• BAL is broadly indicated in every patient with unclear diffuse lungdisease ( or ) unclear pulmonary shadowing

• Side effects : include alveolar infiltration , wheezing and bronchospasm , fever

in the first 24 hrs after BAL

• BAL is safe procedure and associated with virtually no morbidity , andcollects samples from a much larger area of the lungs , giving a more

representative picture of inflammatory and immunological changes • In some disorders , specific information may be obtained , e.g., alveolar

proteinosis , diffuse alveolar hemorrhage , malignant infiltrates ( or ) dust

exposure . Here BAL can replace lung biopsy

• Bronchial lavage ( or ) bronchial washing , which requires relatively little instilled

fluid 10-30 ml , and is used for bacteriological study and ( or ) tumor cytology . Toavoid lavage contamination by blood , the BAL should always be made before any concomitant procedure , e.g., biopsy ( or ) bronchial brushing .In diffuse lung disease , the middle ( or ) lingular lobe is used as astandard site of BAL

• Lignocaine :- Indication : Local anesthetic

Contraindication : Hypovolaemia , heart block , hypersensitive



patient’s

Special precautions : Respiratory depression , Epilepsy , CHF ,Bradycardia , Myasthenia gravis

Side effects : Confusion , respiratory depression , convulsions ,

bradycardia , hypotension , and hypersensitivity

• Inhaled steroids providing long-term symptomaticrelief are the first line drugs for treatment of bronchial

asthma

• Vancomycin :- it is primarily active against gram-positive bacteria

. Strains of staphylococcus aureus and those which are

resistant to methicillin ( MRSA ) are inhibited by vancomycin

• Doxapram :- Respiratory stimulant

• The rate and depth of breathing will increase with :1. Acidosis ( metabolic )

C t l t l i ( P )



2. Central nervous system lesions ( Pons )

3. Anxiety

4. Aspirin poisoning

5. Oxygen need ( hypoxemia )

6. Pain

• The rate and depth of breathing will decrease with :1. Alkalosis ( metabolic )

2. Central nervous system lesions ( Cerebrum )

3. Myasthenia gravis

4. Narcotic Overdoses5. Obesity ( extreme )

• Respiratory insufficiency and failure are major life threatening

complications of COPD

• Because hypoxemia is a stimulus for respiration in the patient with



• Because hypoxemia is a stimulus for respiration in the patient with

long-standing COPD , increasing the oxygen flow rate may

raise the oxygen level in the patient’s blood but lead todepression of the respiratory drive and retention of carbon dioxide .

Monitoring the patient’s respiratory response to oxygen

administration is a priority

• Bullae , are a feature of progressive emphysema . Bullae are seen mostfrequently in smokers and located in the apices of the lungs , more often on the

right than on the left side

• Acute epiglottitis in children is mostly caused by

Haemophilus influenzae type B . Antibiotic of choice foracute epiglottitis is Cephalosporin . Securing an airway by

intubation must be first line of treatment in a child with

suspected diagnosis of epiglottitis

• Examples of Drug-induced Pulmonary Disease :

1. Bleomycin ; Amiodarone Pneumonitis and Fibrosis



y

2. Methotrexate ; Nitrofurantoin Hypersensitivity

pneumonitis3. Aspirin Bronchospasm

• Left ventricular failure causes dyspnoea , because of a rise of

pressure in the left atrium and pulmonary capillaries leading to

interstitial and alveolar oedema . This makes the lungs stiff (less compliant ) , which increases the amount of respiratory

effort necessary to breathe

• Adult Respiratory Distress Syndrome is known by various

synonyms such as Shock-lung syndrome ; diffuse alveolar damage ;traumatic wet lungs . ARDS occurs from the following causes , i. )Pancreatitis ii. ) Oxygen toxicity iii. ) Diffuse pulmonary infections ;except deficiency of surfactant . The lungs are characteristically stiff ,

congested and heavy

• Ventricular tachycardia and Ventricular fibrillation are

life threatening arrhythmias . Defibrillation is a

t h i t b i id d h ti h th



technique to bring very rapid and chaotic rhythm

back to normal by applying an electrical shock over the chest with a machine called defibrillator . The

most common cause of sudden cardiac death is

Ventricular fibrillation

• Myocardial infarction , better known as a “ heart attack “ , is death of a section of heart muscle due to

prolonged , progressive ischaemia

• Cardiac tamponade occurs when sufficient fluid , usuallyblood accumulates within the pericardial cavity to restrict filling

of the heart during diastole , leading to reduced bloodpressure , tachycardia and eventually cardiac arrest if the

tamponade is not relieved by a pericardial puncture

• Differences • Asthma • COPD

1. Smoking history Not necessarily Yes



2. May start in child-

hood

Yes No

3. Atopy Sometimes No

4. Provocation of

symptoms

Weak stimulus ,e.g., Cold air

Strong stimulus ,e.g., infection

5. Cough at night Patient wakescoughing

Wakes then coughs

6. Sputum Contains

eosinophils

Contains

neutrophils7. Bronchodilator

response

Yes Sometimes

8. Steroid response Yes Sometimes

• Differences • Bronchiectasis • COPD

1 Age Varied Older



1. Age Varied Older

2. Smoking history Not necessarily Usually

3. Auscultation Noisy , maybelocalized

Diffuse Crackles

4. Sputum Excessive , often thick and green

Moderate

5. Haemoptysis Sometimes No

6. Finger Clubbing Sometimes No

7. X-ray Specific Variable

• Exercise – induced asthma :- This is present in 80% of

asthma sufferers and in some is the only manifestation of the

disease Hyperventilation during exercise especially in cold



disease . Hyperventilation during exercise , especially in coldweather , leads to evaporation of airway surface liquid ,

hyperosmolality and heat loss , causing bronchospasm .Bronchospasm occurs during ( or ) up to 10 minutes after

exertion , and recovery is usually complete 30 minutes later

• Occupational asthma :- This may take weeks ( or ) years to

develop . Symptoms usually worsen during the week andease at weekends but several work-free days may be needed

before improvement is apparent . It is usually diagnosed by a

fall in FEV1 of more than 20% over the working day ( or )

working week• Status asthmaticus :- Specifically describes an asthma

attack prolonged over 24 hours , leading to dehydration and

exhaustion

• Nocturnal asthma :- This occurs in 80% of people with asthma ,mostly during REM sleep . It is diagnosed from a morning dip

in Peak Flow of over 20% compared to the previous evening . The



in Peak Flow of over 20% compared to the previous evening . Theterm applies only to those who suffer at night and are symptom-

free in the day . It causes fatigue and interferes with sexualactivity . Possible trigger factors are an exaggerated bronchial

response to cold bedrooms , reduced lung volume in supine ,allergens in bedding . Airways are narrowest at about 4 a.m .

• Effect of Obesity :- The obese and the elderly share atendency towards poor basal ventilation . Obesity reduces lung

volumes and lung compliance . Breathing patterns tend to berapid , shallow and apical . When upright , the weight of the

viscera is normally borne by the pelvis but in obese people it pulls

down on the ribs and increases the work of inspiration .

When supine , the pressure of the viscera on the diaphragm

hinders inspiration

Effect of Ageing1. Decreased elastic recoil , dilation of alveoli , increased lung volume (

senile emphysema ) leading to reduced surface area for gas exchange



senile emphysema ) , leading to reduced surface area for gas exchange

2. Narrowing of small airways , leading to raised closing volume , premature

closure of small airways , alveolar collapse and ventilation-perfusion mismatch 3. Increased residual volume because closure of small airways prevents

full exhalation

4. Greater dependence on collateral ventilation because of airway closure

5. Decreased chest wall compliance

6. Decreased exercise capacity

7. Decreased ventilatory response to both hypoxemia and hypercapnia

8. Decreased vital capacity by 30 ml per year

9. Decreased FEV1 by 30 ml per year and decreased response to Beta 2 –

agonist drugs such as salbutamol10. Increased Blood Pressure , esp. Systolic , because a greater pressure is

needed to overcome the resistance of hardening arteries

• The following have been described after regular physical activity

:

1. Decreased morbidity and mortality



1. Decreased morbidity and mortality

2. Decreased resting heart rate

3. Decreased hypertension , heart disease , diabetes , Osteoporosis , anxiety anddepression

4. Increased respiratory muscle strength

5. With Swimming training , increased lung volumes

6. Exercise that is vigorous and regular reduces the risk of Myocardial infarction

by 50%

Effect of immobility

• Immobility is known to increase the risk of Pneumonia , Deep Vein Thrombosis , Osteoporosis and bedsores

• Immobility leads to Constipation , Urine retention , Deconditioning and depression

• Disuse muscle atrophy is most marked

Effect of Sleep• Sleep is restorative but , for some respiratory patient’s , risky

• Changes during sleep include :



• Changes during sleep include :

1. Decreased mucociliary clearance and decreased cough

2. Decreased muscle tone , including muscles that preserve patency of the airway

in the throat

3. Decreased ventilatory response to hypoxia and hypercapnia

4. Decreased Minute Ventilation by 10-15% , with consequent rise in PaCO2

5. During REM sleep , 25% drop in tidal volume6. Ventilation-Perfusion mismatch due to decreased lung volumes and

hypoventilation

• REM sleep occupies about 20% of total sleep time and is the restorative, dreaming and physiologically eventful phase when oxygen

consumption is highest . Sleep and COPD have a particular relationship . Nocturnal oxygen desaturation speeds pulmonary hypertension and

hypercapnia . Death from lung disease usually occurs at night

• The trachea may be shifted from mid-line with unilateral upper lobe collapse , pneumothorax , pleural effusion , ( or ) lung

tumors



• The trachea shifts toward the collapsed lung but away from the

pneumothorax , pleural effusion , ( or ) lung tumors• Abdominal paradox and respiratory alternans indicates

diaphragmatic fatigue

• COPD would cause a bilateral decrease in chest expansion

• Unilateral chest expansion and reduced ( or ) absent breathsounds would be consistent for a patient with pleural effusion

• Pneumothorax would cause an increased resonance to

percussion of the chest

• Hepatomegaly may be accompanied by the collection of serous fluid in the peritoneal cavity known as ascites . Severe

ascites may restrict diaphragm movement , and contribute to the

onset of Respiratory Failure

• Hypoxemia produces pulmonary vasoconstriction , the

right ventricle must work harder than normalh i ifi t h i i t Thi h i



whenever significant hypoxemia exists . This chronic

workload on the right ventricle may result in rightventricular hypertrophy and poor venous blood flow

return to the heart . When the venous return to theright side of the heart is reduced , the peripheral

blood vessels engorge , resulting in an accumulationof fluid in the subcutaneous tissues of the ankles , called

pedal edema . The edematous tissues pit ( indent ) when pressed firmly with the finger tips . Pedal

edema suggests chronic lung disease that has resulted inCor-pulmonale ( or ) Chronic Heart Failure

Epworth Sleepiness Scale

• Do you fall asleep ? SITUATION :-

1. Sitting and reading



1. Sitting and reading

2. Watching Television

3. Sitting , inactive in a public place ( e.g., a theatre ( or ) meeting )4. As a passenger in a car for an hour without a break

5. Lying down to rest in the afternoon when circumstances permit

6. Sitting and talking to someone

7. Sitting quietly after a lunch without alcohol

8. In a car , while stopped for a few minutes in the traffic

0 = Would never doze . 1 = Slight chance of dozing

2 = Moderate chance of dozing . 3 = High chance of dozing

• The Epworth sleepiness score ; a validated way to assess the impact of

sleepiness on daily activities . The overall score is the addition of each individualitem ( scored 0-3 ) ; thus it can vary between 0 ( no sleepiness ) and 24 ( maximum

sleepiness ) . Normal subjects average 6 with 9 being regarded as the upper limit of

normal . Patient’s with sleep apnoea average 16

• Inward depression of the skin during inspiration is known as

retraction . Retractions may be seen between ribs ( intercostal )

below the ribs ( subcostal ) ( or ) above the clavicles (



, below the ribs ( subcostal ) , ( or ) above the clavicles (

supraclavicular ) . The opposite movement of the skin during

exhalation is known as bulging • Limited pulmonary reserve ( e.g., COPD )

• Ventilation-Perfusion mismatch ( e.g., Atelectasis )

• Stiff lungs ( e.g., Adult Respiratory Distress Syndrome )

• Low Oxygen availability ( e.g., High altitude )• Iatrogenic pneumothorax , may be caused by puncture of the lung with the

aspirating needle , used for the procedure

• Cystic Fibrosis is an inherited disease of secretory epithelia that

affects the airways , liver , pancreas , and sweat glands . It is themost common lethal genetic disease in whites . The cause of cystic fibrosis is a genetic mutation affecting a transporter

protein that carries chloride ions across the plasmamembranes of many epithelial cells

• There are a number of age-related physiologic changes in the

pulmonary system :-

1. Structurally , the trachea and bronchi become more rigid with age



y , g g

2. Smooth muscle fibers in the lungs are progressively replaced with fibrous

connective tissue 3. Alveolar septa gradually deteriorate

4. Although the number of alveoli does not change , loss of alveolar wallsincreases the size of the alveoli and reduces surface area for gas exchange

5. The alveolar capillary membrane thickens , reducing diffusion of

pulmonary gases6. Aging lungs have less elastic recoil , which leads to an increase in antero-

posterior diameter

7. The chest wall becomes stiffer

8. The stiffer chest wall and reduction in elastic recoil are factors in an agerelated increase in FRC and RV

9. Ciliary activity slows down , and the loss of an effective cough reflex contributes to the increased susceptibility of older patient’s to lunginfections

• Laryngeal complications of Endotracheal Intubation :-1. Glottic edema The cardinal clinical sign of glottic edema is inspiratory

stridor



2. Subglottic edema

3. Vocal cord paralysis4. Sore throat and “ Hoarse “ voice

5. Vocal cord ulceration , Granuloma , and Polyp

• Potential results of retained secretions :-1. Inflammation and Partial plugging Increased airflow resistanceUneven

distribution of ventilation Ventilation-Perfusion mismatchHypoxemia

Increased work of breathing

2. Total plugging Absorption atelectasis Decreased lung compliance

Increased work of breathing

3. Stasis Pneumonia Fever

• Sleep apnea is a breathing disorder characterized by

repeated collapse of the upper airway during sleep , with

consequent cessation of breathing Patient’s may also



consequent cessation of breathing . Patient s may also

unknowingly experience frequent arousals during the night ,

resulting in chronic day time sleepiness ( or ) fatigue

• There are two discrete types of sleep apnea :-

1. Central Sleep Apnea , characterized by a lack of airflow in the

absence of ventilatory effort , is rare

2. Obstructive Sleep Apnea is characterized by closure of the

upper airway , resulting in the cessation of airflow despite

persistent ventilatory effort

• Weight reduction , can increase upper airway cross-sectional area and , in some individuals , OSA may

be cured

• Apnea is defined as cessation of airflow for more than 10

seconds . A related event , hypopnea , is characterized by a

reduction in airflow associated with a decrease in oxygen



reduction in airflow associated with a decrease in oxygen

saturation

• The average number of apnea-hypopnea events per hour of

sleep is called the Apnea-Hypopnea Index ( AHI )

• Patient’s with sleep apnea are more likely to fall asleep at

inappropriate times and have a higher rate of automobile

crashes and work-related accidents

• The cardiovascular system is also adversely affected by

sleep apnea . There also seems to be a higher prevalence of

sleep apnea in the hypertensive population

• Pickwickian Syndrome ( also known as Obesity-

Hypoventilation Syndrome ) , which consists of daytime

hypercapnia and hypoxemia , pulmonary hypertension ,

polycythemia

• Aspergillus colonises in the bronchi causing allergic

bronchopulmonary aspergillosis ( ABPA )

ABPA h th f ll i h t i ti



• ABPA has the following characteristics :

1. Chest radiography shows opacities2. Peripheral eosinophilia is present

3. High serum IgE , IgM antibodies to Aspergillus , and

proximal cystic bronchiectasis are characteristic findings

• Non-steroidal Anti-inflammatory agents are , aspirin; ibuprofen ; sodium salicylate

• Short-term cough is most frequently caused by viral infection

. Smoking is the most common cause of chronic cough .

Post nasal drip syndrome ; asthma and gastro-oesophageal reflux are responsible for most causes of persistent cough in non-

smokers

• CPAP acts as a pneumatic splint by increasing the

pressure in the oropharyngeal airway , thereby maintaining airway patency throughout the



maintaining airway patency throughout the

ventilatory cycle • Atropine :- Pre-operative medication to inhibit secretions

and salivation , sinus bradycardia , antidote fororganophosphorus poisoning

• Digoxin :- The main action is its direct effect on heart toincrease the force of myocardial contraction . Indications :

Congestive Cardiac Failure , Cardiac dysarrhythmias

• We must administer 100% oxygen for the patient’s who has got pneumothorax till he gets well . Thiscauses nitrogen to be washed out of the body ( or ) sothat the trapped air is more rapidly absorbed

• Congestive Heart Failure is a complex clinical syndrome

that can result from any functional ( or ) structural cardiac

disorder that impairs the ventricle’s ability to fill with ( or )



p y ( )

eject blood . CHF results in pulmonary vascular

congestion and reduced cardiac output . The measurement

of serum brain natriuretic peptide and echocardiography have

substantially improved the accuracy of diagnosis . The

cornerstone of treatment is a combination of an angiotensin-

converting-enzyme inhibitor and slow titration of a beta-blocker

• Patient’s with CHF are prone to pulmonarycomplications , including Obstructive Sleep Apnea ,

Pulmonary edema , and Pleural effusions

• CPAP and NIPPV benefit patient’s in CHF

exacerbations

• Criteria for the diagnosis of CHF :-

1 Neck-vein distention



1. Neck-vein distention

2. Orthopnea ( or ) Paroxysmal Nocturnal Dyspnea3. Cardiomegaly on chest radiograph

4. S3 gallop

5. Left ventricular dysfunction on echocardiogram

6. Hepatomegaly

7. Central Venous Pressure > 12 mmHg

8. Weight loss > 4.5 kg in response to CHF treatment

• Pulmonary Arterial Hypertension is a pathological condition of the small pulmonary arteries . PAH is characterized histopathologically by vasoconstriction , vascular proliferation , in



situ thrombosis . These pathologic changes result in progressive

increase in the mean pulmonary artery pressure and pulmonaryvascular resistance , which , if untreated , leads to right-ventricular

failure and death

• Hemodynamically , PAH is defined as an increase in the

mean pulmonary arterial pressure to > 25 mmHg at rest (or ) > 30 mmHg during exercise

• Transthoracic echocardiogram is an excellent

screening tool to evaluate PAH , but every patient

requires a right-side heart catheterization to help stage

the disease and guide therapy

• Diseases that affect both Lungs and the Kidneys :-

1. Wegener’s Granulomatosis

2 Systemic Lupus Erythematosus



2. Systemic Lupus Erythematosus

3. Good pasture’s Syndrome

• Major indications for Lung Transplantation by

procedure :-

1. COPD2. Pulmonary fibrosis

3. Bronchiectasis

4. Cystic Fibrosis

5. Sarcoidosis6. Alpha-1 antitrypsin deficiency

Pleural effusion

• Definition :- Pleural effusion occurs when too much fluid

collects in the pleural space It is commonly known as “



collects in the pleural space . It is commonly known as

water on the lungs “ . It is characterized by shortness of breath ,

chest pain , gastric discomfort ( dyspepsia ) , and cough

• Description :- There are two thin membranes in the chest , (

the visceral pleura ) lining the lungs , and ( the parietal pleura )

covering the inside of the chest wall . Normally , small blood

vessels in the pleural linings produce a small amount of fluidthat lubricates the opposed pleural membranes so that they

can glide smoothly against one another during breathing

movements . Any extra fluid is taken up by blood and lymph

vessels , maintaining a balance . When either too much fluidforms ( or ) something prevents its removal , the result is an

excess of pleural fluid ( an effusion ) .

• There are two types of pleural effusion ; the transudate and theexudate

1. A transudate is a clear fluid , similar to blood serum , that forms not

b th l l f th l di d b t b



because the pleural surfaces themselves are diseased , but because

the forces that normally produce and remove pleural fluid at the same

rate are out of balance

2. An exudate – which often is a cloudy fluid , containing cells and much protein

– results from disease of the pleura itself . The most common causes are

infections such as bacterial pneumonia and tuberculosis

• Causes of transudative pleural effusion :1. Congestive Heart Failure

2. Cirrhosis

• Causes of exudative pleural effusion :

1. Pleural tumors2. Tuberculosis in the lungs

3. Pneumonia

4. Pulmonary embolism

• Diagnosis :- When pleural effusion is suspected , the best way to confirm itis to take chest X-rays , both straight-on and from the side . In order to learn

what has caused the effusion , a needle ( or ) catheter is often used to

obtain a fluid sample , which is examined for cells and its chemical make-



p ,

up . This procedure , called a thoracentesis , is the way to determine

whether an effusion is a transudate ( or ) exudate , giving a clue as to theunderlying cause . If the effusion is caused by lung disease , placing aviewing tube ( bronchoscope ) through the large air passages will allow the

examiner to see the abnormal appearance of the lungs

• Treatment :- The best way to clear up a pleural effusion is to direct treatment

at what is causing it , rather than treating the effusion itself . Because pleuraleffusion is a secondary effect of many different conditions , the key to

preventing it is to promptly diagnose the primary disease and provide effective

treatment . Timely treatment of infections such as tuberculosis and

pneumonia will prevent many effusions . If large effusions continue to

recur , a drug ( or ) material that irritates the pleural membranes can be

injected to deliberately inflame them and cause them to adhere close

together – a process called sclerosis . This will prevent further effusion

by eliminating the pleural space

• Chronic bronchitis : it is defined by productive cough on mostdays for at least three months for at least two consecutive

years and which cannot be attributed to other pulmonary



causes

• Emphysema : it is characterized by destruction of alveolar walls , resulting in abnormal and permanent enlargement of

airspaces and loss of lung elasticity , with consequent

obstruction of peripheral airways distal to the terminal

bronchiole• Bronchiectasis : Copious purulent sputum , Clubbing , Coarse

crackles , confirmed by HRCT scan

• Bronchodilator reversibility testing : This test should be

performed when patient’s are clinically stable and free frominfection . An increase in FEV1 ( or ) FVC that is both greater than 200 ml and a 12% increase over the Pre-bronchodilator value

indicates reversibility

• Smoking history : 1 pack-year = 20 cigarettessmoked per day for 1 year

Total pack-years = ( No. of cigarettes smoked / day ) multiply by number of



p y y

years of smoking / 20

• Usually , there is a smoking history of > 20 pack-years

• Risk factors that can contribute to the causation of COPD

1. History of regular smoking for at least 10 years

2. Alpha-1 antitrypsin deficiency 3. Age > 40 years

4. Occupational exposure e.g., coal mines ; cotton industries

5. Chest infections during the first year of life

6. Reduced intake of antioxidant vitamins E & C7. Low birth-weight

8. Low socio-economic status

• Treatment of COPD :-1. Smoking cessation : is the only way by which the accelerated rate of decline

of FEV1 can be arrested . This is the most cost-effective treatment

h B h dil t



2. Drug therapy : Bronchodilators ( Anticholinergics and Beta2-agonists ) are

the cornerstone in the management of COPD3. Nutrition

4. Vaccination : Influenza and pneumococcal vaccines are recommended

5. Domiciliary oxygen therapy : is indicated in patient’s with persistenthypoxaemia . LTOT must be given for at least 15 hours at a rate of 2-4 L /

min daily to achieve benefit6. Pulmonary rehabilitation : involves patient education , psychosocial

support , chest physiotherapy , exercise and muscle training . It helps

the patient to cope with his/her disease

7. Lung volume reduction surgery ( LVRS ) is applicable to patient’s with

severe disease in whom there is a very marked increase in FunctionalResidual Capacity ( FRC ) and air trapping

• Tumors are classified as benign and malignant :-

• Benign tumors :

1. Usually have a capsule surrounding them



2. Remain localized

3. Do not invade neighboring tissue ( or ) metastasize4. Have cells resembling the normal cells from which they originate

• Malignant tumors :

1. Are not capsulated

2. Infiltrate tissue , adhering to the skin , muscle and bone

3. Invade at a distance , with adenopathy and metastasis

4. Do not resemble the cells from which they originate

• The symptoms most often found in cancer of the lung are cough , haemoptysis , loss of weight , thoracic pain and dyspnea

• The diaphragm is a musculo-aponeurotic sheath thatseparates the thoracic and abdominal cavities

• Depression of the diaphragm may be due to pleural effusions ,



pneumothorax , asthma ( or ) emphysema

• Lesions to the cervical nerves ( 3 , 4 , 5 ) and phrenic nerve can giverise to a bilateral paralysis of the diaphragm

• If administered for a long period , oxygen can promote a hemorrhagic

pneumonia , termed oxygen poisoning . Concentrations in the range

of 55-60% for prolonged periods can produce changes such as atelectasis , pneumonitis , coma and even death

• Patient’s with chronic lung disease breathing 100% oxygen may

evidence a marked decrease in the respiratory minute volume

• The causes of diminished breath sounds are as follows :- 1. ) Fluid in the pleural space 2. ) Air in the pleural space 3. )

Thickening pleura caused by fibrosis 4. ) COPD ,as a result of over

inflation of the lung 5. ) Bronchial obstruction 6. ) Hypoventilation of the lung

• Signs and symptoms of pulmonary distress :-1. Dyspnea

2. Cyanosis



y

3. Palpitations

4. Tachypnea

5. Chest pain

6. Cough

7. Sputum8. Wheezing

9. Stridor

10. Paradoxical breathing patterns

11. Trachea positioned off – midline

12. Cavitations of chest wall during inspiration

13. Unequal excursions of chest wall during inspiration

• The surfactant is secreted by the Type 2 alveolar cells , andlines the alveolar surface . Chemically , the surfactantcontains the surface tension lowering agent , dipalmitoyl

l i hi d l f i i f h f



lecithin , and also a few proteins . Lowering of the surface

tension by the surfactant improves the distensibility of the lungs .Reducing the muscular effort required for breathing is thefirst function of the surfactant

• Alpha-1-antitrypsin ; protects the respiratory tract from neutrophil elastase , an omnivorous connective tissue protease

capable of cleaving all forms of connective tissue , includinglung parenchyma . The central tenet of the pathogenesis of

emphysema is that alveolar walls are destroyed , because of insufficient protection against neutrophil elastase

• Cyanosis :-1. is an unreliable sign

2. can only be detected when saturation falls to 85%



y 5

3. may be absent when associated with severe anaemia

4. is exaggerated when associated polycythemia

• Clubbing :-

1. is usually bilateral and usually affects both fingers and toes

2. lesser degrees are difficult to identify clinically

3. increased curvature of the nail bed

4. increase in the bulk of the nail bed and terminal phalanx ( if extreme this gives the appearance of a drumstick )

5. sponginess of the nail bed , which gives the feeling that thenail is floating on its bed

• Vital signs :-1. Temperature ( “ Wunderlich curves “ )

2. Pulse rate ( speed , force and duration )



3. Respiratory rate (is the only vital sign that is under voluntary control)

4. Blood pressure5. Arterial oxygen saturation

• Takuo Aoyagi of japan discovered the basic principle of pulse

oximetry :- Pulsatile transmission of light through tissue depends

on the patient’s arterial saturation . The most common causesof inadequate oximeter signals are poor perfusion due to cold

( or ) hypotension ; excessive ambient light ; and motion artifact

. Limitations of pulse oximetry :- Because pulse oximetry readings indicate only the degree of oxygen saturation of hemoglobin , they fail to detect problems of poor oxygen

delivery ( e.g., anemia ; poor cardiac output ) ; hyperoxia ; and

hypercapnia

• Cell death is called necrosis . One example of necrosis is the pressure sore which may occur over a bony point in a bedridden

patient

G Wh i ff f i h



• Gangrene :- When necrosis affects a mass of tissue such as a

digit ( or ) limb , it is called gangrene . An example , is the gangrene of a toe resulting from an obstructed blood supply . Thetoe becomes purplish and may eventually go black . This blackening is probably due to the slow drying and oxidation of

haemoglobin in the tissues . The main cause of the necrosis is

lack of oxygen ( tissue anoxia )

• Pleura :- a delicate serous membrane

• Pleural space ( or ) cavity :- normally has minimal volume , unless

lungs collapse ( or ) air / fluid collects between the two layers . In

anatomy , the pleural cavity is the potential space . The pleurathat is connected to the chest wall is parietal pleura and is

highly sensitive to pain

Pleural Fluid Examination• Normal pleural fluid is clear and pale yellow in color . Usually only

small amounts of fluid are present ( < 20 ml ) . Increased pleural fluid



occurs most commonly with heart failure but also with liver disease , infections ,

and tumors . Opaque ( or ) turbid fluid is characteristic of infections in whichthere are large numbers of WBCs in the fluid . Actual cell counts may beperformed on the fluid . The type of WBC present may be useful indetermining the type of infection present . The level of protein occurringin pleural fluid may also be determined . Fluid may accumulate in the pleural

cavity as transudate ( or ) exudate . Exudate is cloudy with a high protein contentas opposed to transudate which is clear with a low protein content . Consequently

exudate tends to become consolidated where as transudate can be reabsorbed if

the underlying condition is treated . A protein level of less than 3g/dL is

characteristic of a transudate . Exudates have a protein content of

3g/dL ( or ) more . Culture of the fluid for microbiologic organisms andcytologic examination for malignant cells are other tests commonly

performed on pleural fluid

• The ambient pressure increases by 1 atmosphere for every 10 m of depth in seawater . The invention of SCUBA gear ( self-contained underwater breathing apparatus , a tank-and-

valve system carried by the diver ) transformed diving from



valve system carried by the diver ) transformed diving from

a business into a sport • Potential problems associated with exposure to

increased barometric pressure :-

1. Oxygen toxicity

2. Nitrogen narcosis

3. Decompression sickness ( Caisson disease ; Bends ; Diver’s

paralysis ; Dysbarism )

4. Air embolism

• Surfactant , reduces the work of breathing ( increases compliance

) by decreasing alveolar surface tension

• Dyspnea ; is the symptom of abnormal awareness of breathing . Itmay occur following exertion , after excitement ( or ) after a

heavy meal

Th ’ i t f ti b l d till



• The person’s respiratory functions may be normal and still

dyspnea may be experienced because of an abnormal state of mind . This is called neurogenic dyspnea ( or ) emotional dyspnea

. Example :- Person who have a psychological fear of not beingable to receive a sufficient quantity of air , such as on enteringsmall ( or ) crowded rooms

• The normal adult thorax , has an antero-posterior diameterless than the transverse diameter . The antero-posteriordiameter normally increases gradually with age andprematurely increases in patient’s with COPD . This abnormal

increase in antero-posterior diameter is called “ barrel chest “ .When the antero-posterior diameter increases , the ribs lose their

normal 45* angle of slope in relation to the spine and become

horizontal

• Common features of Obstructive Sleep Apnea :-

• Day time :

1 Daytime sleepiness



1. Daytime sleepiness

2. Morning headache3. Increased frequency of accidents

4. Falling asleep during routine activities ( e.g., working ordriving )

5. Hallucinatory images , irritability , personality changes

• Nocturnal / while sleeping :1. Snoring

2. Apneic episodes3. Restlessness , flailing about in bed

4. Frequent urination , bed wetting , loss of libido

• Patient’s with COPD may use pursed-lip breathing duringexhalation . Some patient’s naturally begin to pucker theirlips during exhalation , to provide a slight resistance to the

exhaled breath This resistance theoretically provides a slight



exhaled breath . This resistance theoretically provides a slight

back-pressure in the airways during exhalation and prevents their premature collapse

• Nasal flaring ; is identified by observing the external nares flareoutward during inhalation . This occurs especially in neonates with

respiratory distress and indicates an increase in the work of

breathing

• When respiratory disease results in reduced oxygenation of the arterial blood , cyanosis may be detected , especially around

the lips and oral mucosa . The ability to see cyanosis depends on

the lighting in the room and the patient’s hemoglobin level .

Reduced hemoglobin concentration in the blood prevents visible

cyanosis , even if hypoxemia is present

• The patient’s breathing pattern often providesstrong clues to the underlying pathologic

condition :



condition :

1. Rapid and shallow breathing suggests a loss of lung volume

2. A prolonged expiratory time indicates intrathoracicairway obstruction

3. A prolonged inspiratory time indicates upper airway obstruction

• Anastomosis :- a natural communication , direct ( or

) indirect , between two blood vessels• Aneurysm :- Localized abnormal dilatation of a

blood vessel

• Respiratory acidosis :- An acid-base imbalancecharacterized by a pH less than 7.35 , because of an

increased level of carbon dioxide in the blood



• Respiratory alkalosis :- An acid-base imbalancecharacterized by a pH greater than 7.45 , because of

excessive ventilation

• Shunt :- A bypass ; in the lungs , an area in which

blood flows through the lungs without coming intocontact with alveolar gas

• Exercise , is the body’s most common physiological stress , and it

places major demands on the cardiopulmonary system

• Ventilatory Oxygen uptake ( VO2 ) ; is the amount of oxygen that is extracted from inspired air as the body performs work

• Relative contraindications to performing spirometry :-1. Hemoptysis of unknown origin ( Forced expiratory maneuvers

may aggravate these conditions )



2. Pneumothorax

3. Unstable cardiovascular status ( or ) recent myocardial infarction ( or ) pulmonary embolus ( Forced expiratory maneuver may

worsen angina ( or ) cause changes in blood pressure )

4. Thoracic , abdominal , ( or ) cerebral aneurysms ( danger of

rupture resulting from increased thoracic pressure )

5. Recent eye surgery ( e.g., Cataract )

6. Presence of an acute disease process that might interfere with test performance ( e.g., nausea , vomiting )

7. Recent surgery of thorax ( or ) abdomen

• Hazards and Complications of performingspirometry :-



1. Pneumothorax2. Increased intracranial pressure

3. Syncope , dizziness , light-headedness

4. Chest pain

5. Paroxysmal coughing

6. Bronchospasm

7. Oxygen desaturation resulting from interruption of

oxygen therapy

8. Prone to get nosocomial infections

• Spirometry is often performed as a screening procedure ( examination ofa group , to separate well persons from those who have an undiagnosed

pathologic condition ( or ) who are at high risk ) . It may be the first test to

indicate the presence of pulmonary disease



• Flow Volume Loop :- Also known as F / V curve – the forcedexpiratory maneuver plotted with flow expressed as liters per

second on the vertical axis , and volume expressed as liters on the

horizontal axis . When compared with a traditional spirogram tracing , it

has the advantage of allowing easier recognition of unacceptable ( or ) poorly

reproducible maneuvers and small ( or ) upper airway obstruction

• Hyatt popularized plotting flow versus volume to display a Flow – Volume Loop

• Vital Capacity is an important indicator of the patient’s ventilatory

reserve . A significant reduction in VC indicates that the patient is at higher risk

for respiratory failure , especially after surgery

• Collapse ( most commonly due to bronchogeniccarcinoma )

• Fibrosis ( commonly in tuberculosis )



• Cavity ( Tuberculosis ; Lung abscess )• Consolidation ( Pneumonias )

• Intercommunicating channels for collateral ventilation are Alveolar pores of kohn ; and Canals of

Lambert

• Left Ventricular Failure ( Cardiac asthma )

• The term “ respiratory insufficiency “ ; may be used to

describe the condition in which the blood gases arenormal at rest but become abnormal on exercise

• 1 KPa unit = 7.5 mmHg

Pulmonary Vascular Disease• Pulmonary embolism :- the blockage of a pulmonary artery by foreign matter . The

obstruction may be fat , air , tumor tissue , ( or ) a thrombus that usually arises

from a peripheral vein ( most frequently arising from the deep veins of the legs ) .

P l b li i d t t d b h t di hi fil d l



Pulmonary embolism is detected by chest radiographic films , and pulmonary

angiography • Patient’s with venous thrombosis in the proximal venous system of the lower

extremities and in the upper extremities are at high risk of development of

pulmonary embolism

• Conditions predisposing to venous thrombosis and pulmonary thromboembolism :- Prolonged bed rest ; Pregnancy ; Long periods of travel ;

Obesity ; Carcinoma

• Symptoms :- Dyspnea ; Pleuritic pain ; Cough ; Leg swelling ; Leg pain

• Management of Venous thromboembolism includes anticoagulation therapy (

heparin and warfarin ) . Mechanical measures include early ambulation ; wearing

elastic stockings ; pneumatic calf compression and electric stimulation of calf muscles

• Pulmonary hypertension :- a condition characterized by abnormally highpulmonary artery pressures , that is , mean pulmonary artery pressures in

excess of 22 mmHg . Normal mean pulmonary artery pressure is 10 – 20

mmHg

• Myocardial infarction :- Occlusion of a coronary artery resulting in distalmyocardial tissue necrosis , often accompanied by significant complications

• Angina pectoris :- a paroxysmal attack of severe chest pain associated with

coronary insufficiency ; commonly radiates from the heart to the shouldersd



and arms

• Shock :- a condition in which perfusion to vital organs is inadequate to meettheir metabolic needs ; includes hypovolemic , cardiogenic , septic ,

anaphylactic , and neurogenic forms

• Prolonged bronchoconstriction has been reported following methacholineinhalation challenge . This only occurs if very high concentrations of

methacholine are used . Also , methacholine is unstable when diluted in

phosphate – buffered saline ; therefore normal saline must be used as the diluent .Both histamine and methacholine are stable in solution for up to 3 months atthe concentrations commonly used . Inherent disadvantages to inhaled

histamine are the development of systemic side-effects , such as flushing ,

headache and tachycardia , when high concentrations are inhaled . Theseside-effects are generally not seen with even high concentrations of inhaled methacholine

• Bronchodilator medications must be avoidedbefore the inhalation test :-



1. Short acting Beta-2 adrenoceptor agonists and anticholinergic

agents for at least 8 hours

2. Short acting xanthines for at least 24 hours

3. Long acting xanthines , Beta-2 agonists and some antihistamines

for at least 48 – 72 hours

4. Inhaled ( or ) Oral corticosteroids , Cromolyn ( or )nedocromil are continued without interruption during the

inhalation test because , the effects of inhaled corticosteroids

are slowly progressive over time and may persist for more than 3

months after they are discontinued in mild asthmatics

• Prolonged usage of Corticosteroids frequently results insevere side effects , such as Cushingoid features ;

Osteoporosis ; diminished resistance to infection ;

S di i P i l P i l i



Sodium retention ; Potassium loss ; Peptic ulceration ;mental changes ; and diabetes mellitus

• Systemic Corticosteroids have a number of adverseside effects , including reduction in bone density and

adrenal suppression• Inhaled steroids have relatively few side effects :- Fungal

infection of the Oral Cavity is a common problem (Oral Candidiasis or dysphonia ) and decrease bone

density , and their effect on growth in children is notcompletely understood

• Adrenergic Bronchodilators :- Adverse effects ;1. Tachycardia

2. Palpitations



3. Shakiness4. Nervousness

5. Tremor

6. Headache

7. Insomnia8. CFC propellant – induced bronchospasm

9. Hypokalemia

10. Tachyphylaxis ( repeated exposure to a drug results in

diminished pharmacologic response )

11. Loss of bronchoprotection

• Ipratropium may be preferred in patient’s whoexperience tachycardia ( or ) tremor caused by

adrenergic drugs



• Side effects seen with Anticholinergic aerosol Ipratropium

Bromide :-

1. Dry mouth

2. Cough

3. Eye pain

4. Urinary retention

• Precautions : Use with caution in patient’s with narrow-angleglaucoma , prostatic hypertrophy , constipation ( or )

tachycardia • Non-steroidal anti-inflammatory ( or ) Anti-asthma agents

include Cromolyn sodium , nedocromil sodium and the

antileukotrienes ( Zafirlukast ; Montelukast )

Pathogenesis of Cor pulmonale

• Chronic lung diseases and Pulmonary vascular diseases

Pulmonary resistance Pulmonary hypertension



Pulmonary resistance Pulmonary hypertension

Pressure Overload Right ventricular enlargement Cor pulmonale

• Acute Cor pulmonale occurs following massive

pulmonary embolism

• Congestive Heart Failure , is often used synonymously with left ventricular failure . Failure of the left ventricle may be caused by systemic hypertension ,

Coronary artery disease , ( or ) aortic insufficiency

• The Disadvantages of Artificial Airways :

1. An artificial airway bypasses the normal defencemechanisms which counter bacterial



contamination of the airways . The airways andlungs are more prone to nosocomial infection

2. An endotracheal tube removes the effectiveness of cough because the vocal cords are non-functional ;

a tracheostomy bypasses the cords

3. An artificial airway prevents the patient fromcommunicating vocally . This can be frustratingand frightening , and it is important , in aconscious patient , to provide a pad and a pen tohelp the patient communicate in writing

• The chief indications for an ‘immediate ‘ airway are :-



1. Severe life – threatening upperairways obstruction

2. Cardiac ( or ) Respiratory arrest ( or ) impendingcardiorespiratory arrest

3. Fulminant Pulmonary oedema

• Care over suction of secretions :-1. Use ‘ no – touch ‘ sterile technique

2. Pre-oxygenate ( with high FIO2 ) a haemodynamically unstable patient before suction



unstable patient before suction

3. Do not suck for more than 10 seconds

4. Do not use a very large bore catheter for suction

5. If possible , suck through an adaptor so that ventilatorsupport on high – flow oxygen is not interrupted

6. Stop suction if bradycardia ( or ) hypotension occur ;increase FIO2 to 100 percent for a short time

7. Liquefy viscid secretions ; use physiotherapy

8. Humidify inspired gas• Care of cuff :- Measure cuff pressure daily , and keep this

within acceptable limits ( 14 – 24 cm H2O )

• Complications of Oxygen therapy :-

1. Progressive Hypercapnia



2. Circulatory Depression3. Drying and Crusting of secretions in the

respiratory tract

4. Danger of Oxygen withdrawal5. Oxygen toxicity

a. ) Lung toxicity

b. ) Retrolental Fibroplasia

c. ) Cerebral Oxygen toxicity

• Features of a severe attack of asthma :-

1. Inability to complete sentence in one breath



2. Disturbance in level of consciousness3. Respiratory rate > 30 / min

4. Silent chest

5. Respiratory muscle fatigue6. Tachycardia > 110 / min

7. Peak expiratory flow ( PEF ) < 30 percent of

predicted ( or ) known best8. Cyanosis

Asthma• Definition :- Obstructive airway disease characterized by

reversible airway narrowing , mucus hypersecretion ,inflammation and episodic shortness of breath



inflammation , and episodic shortness of breath• Increased airway responsiveness is related to inhalation of antigens , viral infections , air

pollution , ( or ) occupational exposure . Spirometry is the most useful tool for detecting

reversible airway obstruction . Improvement in the FEV1 ( or ) FVC is the hallmark of

reversibility . Peak expiratory flow ( PEF ) , measured using portable peak flow meters ,

can provide immediate information for a clinician ( or ) patient to modify therapy . There

appears to be a hereditary component to asthma ; many cases occur in patients who have afamily history of asthma ( or ) allergic disorders . Agents ( or ) events that cause an

asthmatic episode are called triggers . Bronchial provocation tests using methacholine ,

histamine , exercise , ( or ) hyperventilation are often used to make the diagnosis of

hyperreactive airways in patients who appear normal but have episodic symptoms . Skin

testing is also used to demonstrate sensitivity to inhaled antigens . Asthma education

usually focuses on helping the affected individual identify and avoid triggers

Chronic Obstructive Pulmonary Disease• Definition :- The term COPD is often used to describe long-standing airway obstruction

caused by emphysema , chronic bronchitis , ( or ) asthma . These three conditions may

be present alone ( or ) in combination . Bronchiectasis is sometimes considered a

component of COPD COPD is characterized by dyspnea at rest ( or ) with exertion



component of COPD . COPD is characterized by dyspnea at rest ( or ) with exertion ,

often accompanied by a productive cough • COPD is a chronic disorder that limits a patient’s ability to work and , in severe cases ,

impairs the activities of daily living . The most prominent symptoms of COPD are

dyspnea and an impaired exercise capacity

• Patients with COPD manifest decreased exercise tolerance . The most important factors

thought to contribute to this limitation are :-

1. Alterations in pulmonary mechanics

2. Dysfunction of the respiratory muscles

3. Peripheral muscle dysfunction

4. Abnormal gas exchange

5. Malnutrition6. Development of dyspnea

7. Active smoking

• Calibration is the process in which the signal froman instrument is adjusted to produce a known

output . The verification step should include a



range of flows to demonstrate volume accuracythat is independent of flow

• Technologist’s comments :- Scoring ( or ) grading the quality of a

patient’s test is an important component of quality assurance for pulmonary

function testing . The technologist’s comments should be added to the final report. The commentary should be based on standardized criteria . If a particular test

meets all criteria , that fact should be stated . Failure to meet any of the

laboratory’s criteria should be documented as well . The reason the patient was

unable to perform the test acceptably should be explained whenever possible .

Failure to meet criteria for acceptability does not necessarily invalidate a test .For some patients , their best performance may fail one ( or ) more of the criteria

• Allen’s test :- Momentary occlusion of the radial and ulnar arteries to establish adequacy of collateral circulation

• BMR ( Basal metabolic rate ) :- the metabolic rate ( i.e., oxygen

consumption ) of a healthy individual at rest



p ) y

• Borg scale :- One of several numeric scales used to rateperceived exertion during exercise testing

• Deconditioned :- Refers to the effects of lack of exercise ,

usually including elevated heart rate and blood pressure and

muscular inefficiency• Dead space :- The volume of the lung that is ventilated but not

perfused by pulmonary capillary blood flow

• Desaturation :- Reduction of oxygen level caused by

dissociation of O2 from Hb• Predicted value :- The expected ( or ) reference value for a

lung function test ; usually derived from studying a large

population of healthy individuals

• Respiratory acidosis :- An acid-base imbalance characterized by a pH less than 7.35 because of an increased level of CO2 inthe blood

• Respiratory alkalosis :- An acid-base imbalance characterized



p y

by a pH greater than 7.45 because of excessive ventilation• Metabolic acidosis :- An acid-base imbalance characterized by

a pH less than 7.35 resulting from accumulation of acid (other than that produced by CO2 ) ( or ) loss of base

• Metabolic alkalosis :- An acid-base imbalance characterized by a pH greater than 7.45 resulting from accumulation of base (

or ) loss of acid ( other than that produced by CO2 )

• Pulse Oximetry :- Estimation of arterial saturation by analysis

of light absorption of blood pulsing through a capillary bed (finger ( or ) earlobe )

• Medullary centers :- Those areas of the medullaoblongata that are responsible for controlling therate and depth of breathing

Ai



• Airways :-

1. Divided into a conducting zone and a respiratory zone

2. Volume of the anatomic dead space is about 150 ml

3. Volume of the alveolar region is about 2.5 – 3.0 liters

4. Gas movement in the alveolar region is chiefly by diffusion• Most of the area of the alveolar wall is occupied by

capillaries

• When oxygen moves through the thin side of the blood-gas

barrier from the alveolar gas to the hemoglobin of the red blood cell it traverses the following layers in order :Surfactant , epithelial cell , interstitium , endothelial cell , plasma

, red cell membrane

• The mean pressure in the pulmonary artery is only about 15 mmHg at rest

• Following statements about the removal of inhaled dust in the

lung are TRUE :-



1. Particles that deposit on the airways are removed by the mucusescalator

2. The escalator is propelled by millions of tiny cilia

3. The mucus comes from mucous glands and goblet cells in the bronchial walls

4. Particles that reach the alveoli are engulfed by macrophages

• Lung Volumes :-

1. Tidal volume and vital capacity can be measured with a simplespirometer

2. TLC , FRC and RV need an additional measurement by helium dilution( or ) the body plethysmograph

3. Helium is used because of its very low solubility in blood

4. The body plethysmograph depends on Boyle’s Law PV = K at constanttemperature

• Ventilation :-1. Total ventilation is tidal volume * respiratory frequency

2. Alveolar ventilation is the amount of fresh gas getting to the alveoli

3. Anatomic dead space is the volume of the conducting airways , about



150 ml4. Physiologic dead space is the volume of gas that does not eliminate CO2

5. The two dead spaces are almost the same in normal subjects , but thephysiologic dead space is increased in many lung diseases

• Fick’s Law of Diffusion :- Rate of diffusion of a gas through a

tissue slice is proportional to the area but inversely proportional to the thickness . Diffusion rate isproportional to the partial pressure difference

• Measurement of Diffusing Capacity :-

1. Carbon monoxide is used because the uptake of this gas is diffusion-limited

2. Normal diffusing capacity is about 25 ml.min-1.mm Hg-1

3. Diffusing capacity increases on exercise

• All of the following would be expected to reduce the diffusingcapacity of the lung for carbon monoxide :-

1. Emphysema which causes loss of pulmonary capillaries

2. Asbestosis which causes thickening of the blood-gas barrier



3. Pulmonary embolism which cuts off the blood supply to part of the lung4. Severe anemia

• Pulmonary Vascular Resistance :-

1. Decreases on exercise because of recruitment and distention of capillaries

2. Increases at high and low lung volumes

3. Increases with alveolar hypoxia because of constriction of smallpulmonary arteries

• Four causes of Hypoxemia :-

1. Hypoventilation2. Diffusion limitation

3. Shunt

4. Ventilation-perfusion inequality

• Hypoventilation :-1. Always increases the Pco2

2. Decreases the Po2 unless additional O2 is inspired

3 Hypoxemia is easy to reverse by adding O2



3. Hypoxemia is easy to reverse by adding O2

• Shunt :-

1. Hypoxemia responds poorly to added inspired O2

2. When 100% O2 is inspired , the arterial Po2 does not rise to

the expected level – a useful diagnostic test• CO2 carried as : dissolved , bicarbonate , carbamino

• Respiratory Muscles :-

1. Inspiration is active ; expiration is passive during rest

2. Diaphragm is the most important muscle of inspiration ; itis supplied by phrenic nerves which originate high in thecervical region

• Pulmonary Surfactant :-1. Reduces the surface tension of the alveolar lining layer

2. Produced by type 2 alveolar epithelial cells

3 Contains dipalmitoyl phosphatidylcholine



3. Contains dipalmitoyl phosphatidylcholine

4. Absence results in reduced lung compliance , alveolaratelectasis , and tendency to pulmonary edema

• Respiratory Centers :-1. Responsible for generating the rhythmic pattern of

inspiration and expiration

2. Located in the medulla and pons of the brain stem

3. Receive input from chemoreceptors , lung and otherreceptors , and the cortex

4. Major output is to the phrenic nerves

• Central Chemoreceptors :-1. Located near the ventral surface of the medulla

2. Sensitive to the Pco2 but not Po2 of blood



3. Respond to the change in pH of the ECF / CSF when CO2 diffuses out of cerebral capillaries

• Peripheral Chemoreceptors :-1. Located in the carotid and aortic bodies

2. Respond to decreased arterial Po2 , increased Pco2and H+

3. Rapidly responding

• Ventilatory Response to CO2 :-1. Arterial Pco2 is the most important stimulus to ventilation

under most conditions and it is normally tightly controlled

2. Most of the stimulus comes from the central



2. Most of the stimulus comes from the central

chemoreceptors but the peripheral chemoreceptors alsocontribute and their response is faster

3. The response is magnified if the arterial Po2 is lowered

• Ventilatory Response to Hypoxia :-

1. Only the peripheral chemoreceptors are involved

2. There is negligible control during normoxic conditions

3. The control becomes important at high altitude , and inlong-term hypoxemia caused by chronic lung disease

• Acclimatization to High Altitude :-1. Most important feature is hyperventilation

2. Polycythemia is slow to develop and of minor value

3 Other features include increase in cellular oxidative



3. Other features include increase in cellular oxidative

enzymes and the concentration of capillaries in sometissues

4. Hypoxic pulmonary vasoconstriction is not beneficial

• Decompression Sickness :-

1. Caused by the formation of N2 bubbles during ascent froma deep dive

2. May result in pain ( “ bends “ ) and neurologicaldisturbances

3. Can be prevented by a slow , staged ascent

4. Treated by recompression in a chamber

5. Incidence is reduced by breathing a helium-oxygen mixture

• Changes at ( or ) shortly after birth :-1. Baby makes strong inspiratory efforts and takes its first

breath

2. Large fall in pulmonary vascular resistance



2. Large fall in pulmonary vascular resistance

3. Ductus arteriosus closes , as does the foramen ovale

4. Lung liquid is removed by lymphatics and capillaries

• Alveolar ventilation increases by the largest percentage at

maximal exercise

• Helium-oxygen mixtures rather than nitrogen-oxygen mixtures ( with the same oxygen concentration ) are preferable for verydeep diving because all of the following are reduced : 1. ) Risk of

decompression sickness 2. ) Work of breathing 3. ) Airway

resistance 4. ) Risk of inert gas narcosis

• Recommended suction pressure for different age groupsare : infants 80 – 100 mm Hg ; children 100 – 125mm Hg ; and adults 120 – 150 mm Hg



• The diameter of the suction catheter should be less thanhalf the inner diameter of the ETT ( or ) tracheostomy

tube , to prevent hypoxia . A simple formula to find outthe appropriate size of the suction catheter is as

follows : Size of ETT ( mm ) * 3 / 2

• Read the tracheal tube cuff pressure on the manometer . Itshould be between 20 – 25 mm Hg

464 critical thinking

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