Clearing awaypulmonary

secretionsExcess or retained pulmonary secretions impair ventilation, invite infection, and may

threaten survival. Find out who’s at greatest risk and how to keep airways clear.BY BILL PRUITT, RRT, AE-C, CPFT, MBA, AND MICHAEL JACOBS, RN, CCRN, CEN, MSN

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EXCESS OR RETAINED pulmo-nary secretions cause a host ofproblems for the patient byincreasing the work of breathingand setting the stage for infection.Frequent coughing as he tries toclear secretions drains his oxygenand energy reserves and makesmuscles sore; coughing may alsospread infection, cause vomiting,or trigger an asthma attack.Allowed to accumulate, excess pulmonary secretions impair gasexchange, which can lead to hyp-oxemia, pneumonia, respiratoryfailure, and death.

Keeping your patient hydrated isa basic step to keeping airwaysecretions fluid and easier to clear.If he’s on mechanical ventilation,he may need humidity added tothe ventilator circuit to prevent theairway from drying out. If he’s

receiving supplemental oxygen andthick secretions are a problem,adding humidity (if the deviceallows) may be appropriate.

Some patients are at greater riskfor problems with pulmonarysecretions than others. In this arti-cle, we’ll describe who they are,how to spot problems early, andwhat to do to prevent complica-tions. For details on the lungs’ nor-mal lines of defense, see A nose(and more) for trouble.

Who needs help?Anticipate problems if your patienthas a disease that increases airwaysecretions. One or more of thesemechanisms is at work.• Increased mucus production bythe goblet cells in the tracheo-bronchial tree inundates small air-ways with excess mucus.

• The mucociliary transport sys-tem, which works like an escalatorto move airway secretions up thetracheobronchial tree where theycan be expectorated, may be dam-aged or impaired.• Airway inflammation and con-striction can slow or prevent theupward movement of airway secre-tions, leaving excessive amountsbelow the level of airway inflam-mation or constriction.

Let’s take a closer look at howthese mechanisms come into playwith diseases likely to cause prob-lems.

Asthma is a chronic inflammato-ry disorder of the airways withintermittent acute exacerbations.It’s characterized by the release ofinflammatory mediators causingreversible spasms of the bronchialtubes, excessive mucus secretion,JO

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failure of the mucociliary transportsystem, and airway inflammationand constriction. During an acuteexacerbation, the patient com-plains of chest tightness and short-ness of breath. Your assessmentmay reveal wheezing, tachypnea,tachycardia, and use of accessorymuscles of respiration. As the asth-ma attack resolves and the airwaysopen, the patient may develop aproductive cough triggered bysecretions that were retained dur-ing airway bronchospasm.

Note that arterial blood gas(ABG) results may reflect respirato-ry alkalosis early in an asthmaattack, proceed to a normal pH,then move into respiratory acidosislate in the attack because of elevat-ed PaCO2 levels. This transitionoccurs if airway bronchoconstric-tion is severe and unrelieved.Patients who have this progressioninto acidosis are at high risk foracute respiratory failure and death.

Chronic bronchitis, a form ofchronic obstructive pulmonary dis-ease (COPD), is characterized byan increased number of goblet cellssecreting excessive amounts ofmucus. The airway walls becomechronically inflamed, reducing air-way diameters. These conditionsraise the risk of mucus plugging.Your assessment may reveal crack-les, wheezes, and gurgles on chestauscultation.

Chronic bronchitis is diagnosedwhen the patient has a productivecough for at least 3 months in 2 consecutive years that can’t beattributed to other causes. As thedisease progresses, ABG analysiswill reveal hypoxemia and respira-tory acidosis with decreased PaO2and increased PaCO2.

Bronchiectasis is a respiratorydisorder characterized by chronicbronchial dilation and inflamma-tion. The mucociliary transportsystem is impaired, and mucusproduction increases. As excessiveairway secretions pool, the epithe-

lial layer lining the airways erodes,predisposing the patient to bacteri-al pulmonary infections. Muscularand elastic components supportingthe airways also are destroyed, ren-dering the dilation and inflamma-tion permanent.

Possible causes of this disorderinclude foreign body aspiration,benign airway tumors, cystic fibro-sis (CF), ciliary malfunction, orallergic bronchopulmonaryaspergillosis.

Your assessment may revealinspiratory and expiratory cracklesthat clear with a cough. Results ofABG analysis are similar to thosefor chronic bronchitis.

Cystic fibrosis is a genetic disor-der characterized by overproduc-tion of thick mucus affecting therespiratory, digestive, and repro-ductive systems. Excessive pul-monary mucus causes a lifetime ofpulmonary inflammation, impairedbreathing, and lung infections. Tomaintain lung function and avoidpotentially fatal infections, patientsmust undergo a rigorous daily regi-men to remove pulmonary secre-tions.

In the past, few patients with CFlived beyond the teenage years. Buttreatment advances have extendedthe median survival age to 32 (asof 2000). Some patients even liveinto their 50s or 60s, so CF is nolonger just a pediatric disorder.

When you assess a patient withan advanced case of CF, or onewho’s having problems with secre-tions, you may find progressivedyspnea and crackles. Results of anABG analysis will reveal hypox-emia and respiratory acidosis withdecreased PaO2 and increasedPaCO2. The patient may becomeincreasingly fatigued and may havedecreased activity tolerance.

Pneumonia results in pooling ofsecretions and debris in the alveoliand lower airways, leading to hyp-oxemia and atelectasis. Bacterial orviral pneumonia develops when

someone breathes in a pathogen oraspirates foreign matter (such asgastric contents) that breeds infec-tion. The body responds by initiat-ing the inflammatory process.Exudate and normal airway secre-tions begin to pool. As these pul-monary fluids collect they becomeviscous, depressing the mucociliarytransport system.

Typical respiratory signs andsymptoms of pneumonia includecough (with or without mucus),chest pain, rapid breathing, crack-les, wheezing, and shortness ofbreath. Nonrespiratory signs andsymptoms include fever, sweating,headache, and weakness. Patientsat particular risk for developingpneumonia include those withchronic illnesses such as diabetes;those with artificial airways; olderadults; chronically ill, immunosup-pressed, or immobile patients; andthose who abuse alcohol.

Neuromuscular diseases such asmyasthenia gravis and Guillain-Barré syndrome cause respiratorymuscle weakness, paralysis, ornerve conduction problems thatcan reduce cough effectiveness andlead to retained secretions. Traumato the central nervous system canalso disrupt the ability to cough orimpair the cough reflex.

Other contributing factorslinked to retained or excessivesecretions include smoking, whichgreatly increases production of air-way secretions and damages themucociliary transport system; airpollution or occupational exposure toirritants, which cause the sameproblems as tobacco smoke; andanalgesia and sedation, whichdepress the cough reflex.

Assessing your patient A thorough nursing assessment isthe key to identifying subtlechanges in your patient’s status,including increased airway secre-tions that obstruct airflow. Followtrends in the patient’s SpO2 and

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ABG values that could indicateimpending respiratory difficulties.Follow these pointers for physicalassessment:• Inspection. Look for signs ofincreased work of breathing(because of resistance to airflow),increased respiratory rate, inter-costal retractions, and increased useof accessory muscles to breathe.• Palpation. Decreased fremitus(palpable vibrations transmittedthrough the bronchopulmonarytree to the chest wall when thepatient speaks) indicate mucusplugging of a bronchus. Test forfremitus by using the ball or ulnarsurface of your hand to palpate thechest while the patient repeatedlysays “99.” When he breathesdeeply, you may also feel chestvibrations related to retained secre-tions; usually this is accompaniedby audible rattling. • Percussion. This technique is oflimited use in trying to detectretained secretions because percus-sion penetrates only 2 to 3 inches(5 to 7.5 cm) in the chest. Still, amucus plug that causes an atelec-tatic lung may produce a dull per-cussion note over the airless area.• Auscultation. Adventitious(added) breath sounds are a hall-mark of retained secretions, butyou may need the patient’s cooper-ation to properly assess breathsounds. A shallow- to medium-sized breath may not produceadventitious breath sounds, so askhim to breathe deeply through anopen mouth. Retained secretionsoften cause crackles and wheezesthat are more common on exhala-tion, but may also be present oninspiration.

Clearing the pipesThe first method you should try toclear secretions is also the simplest:Ask the patient to cough. If he’s justhad abdominal or thoracic surgery,make sure he has adequate analge-sia first and show him how to use a

A nose (and more) for troubleThe same airways that bring oxygen into the lungs also bring in dust,microbes, toxic particles, and smoke that can wreak havoc with normal lungfunction and the patient’s health. Fortunately, the pulmonary system has sev-eral ways to keep itself clean.• Filtering. Nasal hairs stop large particles as air moves into the nares. Themucus layer of the nasal epithelium traps more, smaller particles. Progres-sively smaller particles usually filter out in the lower airways and alveoli.• Mucus. The nose, trachea, and much of the lower airway is lined withmucus-producing goblet cells and ciliated columnar epithelial cells whosecilia act like microscopic brooms. The cilia actual-ly move the mucus blanket (with the trappedparticles) toward the pharynx, a mechanismknown as the mucociliary escalator. Goblet andciliated cells gradually disappear as the airwaysget smaller and aren’t present in the alveoli. Theairways also are surrounded by smooth musclethat constricts to keep harmful particles from get-ting deep into the lungs.• Coughing. The cough reflex helps removesecretions and particles that have landed in thelung. Rapid expiratory flows and positive pres-sure actually shear the mucus free from the air-way walls and carry it out. The larynx, trachea,and mainstem bronchi have receptors that reactto irritants and trigger the cough reflex.

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pillow to splint his incision. Havetissues available to remove anysecretions that he coughs up.

Have him sit in high Fowler’sposition (or stand, if he can); anupright position lets him take in adeeper breath and generate a moreforceful, effective cough. Tell himto wrap his arms around the pillowin a hugging motion, take a deepbreath, hold it for a few secondswhile squeezing the pillow tightagainst his body, then give twocontrolled coughs.

Patients with COPD may haveproblems with premature airwayclosure when attempting a forcefulcough. Teach these patients to usea “huff” cough, which starts from amiddle to low inspiration (not afull inspiration), and to make twoor three expiratory efforts with anopen glottis.

Assisted cough is indicated for apatient with a weak or paralyzeddiaphragm. Place your hands onthe patient’s abdomen, then havehim inhale deeply and cough. Ashe coughs, perform an abdominalthrust in the same way you wouldto clear an obstructed airway.(Remember your basic life supporttraining.) For a patient who can’tinhale, have a colleague give him adeep breath using a resuscitatorbag connected to a mask (for aspontaneously breathing patient)or the artificial airway (for amechanically ventilated patient).

Incentive spirometry can helpprevent atelectasis by filling theunderventilated areas of the lung,reopening alveoli. Incentivespirometry and deep breathing andcoughing improve ventilation andimprove exercise tolerance in respi-ratory muscles. As a result, thepatient may be able to generate amore forceful cough, helping tomove secretions.

Mucoactive agents to clear secre-tions include acetylcysteine, usedto treat patients with chronic bron-chitis, and dornase alfa, used to

treat patients with CF. Anotheroption is guaifenesin, which thinssecretions and is a common ingre-dient in over-the-counter coldmedications.

Suctioning can help clear secre-tions, especially in patients withartificial airways. For patients whoaren’t intubated, use the nasotra-cheal route for suctioning thelower airways. If a patient has areflex cough that clears secretionsfrom the lower airway but can’tremove secretions from his mouth,use a tonsil suction device such asa Yankauer suction device.

Clearing retained secretionsfrom the mouth helps reduce aspi-ration and infection risks. Carefulattention to mouth care reducesmicrobial growth in the mouth andlowers the potential for hospital-acquired pneumonia. (For infor-mation on closed suctioning, see“Clear the Air with ClosedSuctioning” on page 44.)

To perform deep suction, use asterile catheter to reach the lowerairway (below the glottis). Thisstimulates a strong cough in manypatients, which also helps clearsecretions. Even if the patient hasno cough reflex, though, deep suc-tion will often clear secretions.

Chest physiotherapy uses a com-bination of patient positioning(postural drainage) and chest per-cussion or vibration to dislodge andmove secretions from smaller tolarger airways. Patients with a lot ofsecretions (more than 25 ml/day ofsputum), such as those with CF orbronchiectasis, are most likely toneed chest physiotherapy.

Once the patient is positionedappropriately, use your hands or amechanical device to percuss orvibrate a specific area of the lung.Chest physiotherapy is usually per-formed two to four times a day;each procedure may last 10 to 30minutes, depending on how manypositions are being used for postur-al drainage.

Positive expiratory pressure (PEP)consists of taking in a deep breathand exhaling through a device thatresists airflow, creating positivepressure in the lung. This therapyhelps refill underventilated areas ofthe lung, prevents premature air-way closure, and prolongs expira-tion, making more air available tohelp dislodge and move secretionsduring coughing.

Recently, PEP therapy has beencombined with high-frequencycompression/oscillation to mechan-ically move secretions in patientswho aren’t intubated. This combi-nation therapy, given three to fourtimes a day for 10 to 20 minuteseach treatment, makes secretionsless viscous and easier to move.The patient uses a portable, single-patient-use device such as theFlutter valve or the Acapella. Ashe blows through the pipelikedevice, the expiratory flow causesa steel ball (or flipper and mag-net) to move rapidly, generating10 to 25 cm H2O of PEP andhigh-frequency oscillation. Thisdislodges secretions and lets themmove into the larger airways. TheFlutter device must be used whenthe patient is upright. TheAcapella isn’t gravity dependent,and aerosol treatments can beadministered through it simulta-neously with PEP treatment.

High-frequency chest wall oscilla-tion relies on a device to exertexternal forces on the chest toreduce mucus viscosity and mobi-lize secretions. This therapy alsomay enhance the activity and effec-tiveness of the cilia, which increas-es secretion mobility. The patientwears an inflated, nonstretchablevest attached to an air pulse deliv-ery system that delivers oscillatingpressures. (For more details, see“Close to the Vest: A Novel Way toKeep Airways Clear” in theDecember issue of Nursing2003.)He can take his aerosol treatmentsconcurrently with this oscillation

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therapy. Therapy typically includestwo treatments a day, each lasting20 minutes.

Intrapulmonary percussive venti-lation (IPV) is another high-frequency device used to movesecretions, but this one createspressure in the airways rather thanthrough the chest wall. Deliveredthrough a mask, this therapy isindicated for patients breathingspontaneously.

During spontaneous breathing,the IPV device delivers positive air-way pressure along with high-frequency microbursts of air. Thesemicrobursts are delivered on inspi-ration only or during the full inspiratory-expiratory cycle andcreate an oscillating effect in theairways. The device also deliverseither a medication or 0.9% sodi-um chloride solution by aerosol.Treatments typically are given threeto four times a day for 15 to 20minutes each.

Continuous lateral rotation ther-apy can help prevent pooledsecretions in critically ill patients.The patient is placed in a special-

ized bed that rotates from side toside, moving up to about 45degrees in lateral rotation. Gravityhelps move secretions more cen-trally, making them easier for thepatient to cough up (or for you toremove by suctioning).

To perform bronchoscopy, aphysician uses a flexible fiber-opticendoscope to view the airways; atthe same time, he can use thedevice to remove secretions thatcan’t be removed any other way. Hemay perform lavage with a sterile0.9% sodium chloride solution tohelp clear secretions, or he mayinstill a mucolytic to break themdown. The patient is sedated andgiven analgesia so he’s comfortableduring the procedure. Because it’sinvasive and stressful to thepatient, as well as labor-intensiveand costly, bronchoscopy is per-formed only as needed to managesecretions, with a day or morebetween treatments.

Free and clearBy knowing who’s at risk forretained or excess pulmonary

secretions and how to managethem, you can help your patientget the correct treatment and keephis airways open. ‹›

SELECTED REFERENCESFink J. Positive pressure techniques for airwayclearance. Respiratory Care. 47(7):786–796, July2002.

Fink J, Mahlmeister M. High-frequency oscilla-tion of the airway and chest wall. RespiratoryCare. 47(7):797–807, July 2002.

Rubin B, et al. Mucus-controlling drug therapy.In Rau Jr. J, Respiratory Care Pharmacology. St. Louis, Mo., Mosby, Inc., 2002.

Wilkins R, et al. (eds). Egan’s Fundamental ofRespiratory Care, 8th edition. St. Louis, Mo.,Mosby, Inc., 2003.

Bill Pruitt is an instructor in the department ofcardiorespiratory sciences at the University of SouthAlabama in Mobile and a p.r.n. respiratory therapistat Springhill Medical Center in Mobile. MichaelJacobs is a clinical assistant professor in the adulthealth department at the University of SouthAlabama’s College of Nursing and a p.r.n. nursingsupervisor and emergency department staff nurse atOcean Springs (Miss.) Hospital.

The authors have disclosed that they have no signifi-cant relationship with or financial interest in anycommercial companies that pertain to this educa-tional activity.

www.nursing2005.com Nursing2005, July 41

INSTRUCTIONS

Clearing away pulmonary secretionsTEST INSTRUCTIONS• To take the test online, go to our secure Web site at http://www.nursingcenter.com/ce/nursing.• On the print form, record your answers in the test answer sectionof the CE enrollment form on page 42. Each question has only onecorrect answer. You may make copies of these forms.• Complete the registration information and course evaluation.Mail the completed form and registration fee of $16.95 to:Lippincott Williams & Wilkins, CE Group, 2710 Yorktowne Blvd.,Brick, NJ 08723. We will mail your certificate in 4 to 6 weeks. Forfaster service, include a fax number and we will fax your certificatewithin 2 business days of receiving your enrollment form. • You will receive your CE certificate of earned contact hours and ananswer key to review your results. There is no minimum passing grade.• Registration deadline is July 31, 2007.

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SELECTED WEB SITE

RT: The Journal for Respiratory Care Practitioners:Secretion Removal in the ICUhttp://www.rtmagazine.com/Articles.ASP?articleid=R0502F03

Last accessed on June 1, 2005.

Earn CE credit online: Go to http://www.nursingcenter.com/CE/nursing and receive a certificate within minutes.C E

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Clearing away pulmonary secretionsGENERAL PURPOSE To provide nurses with information to accurately assess and safely care for patients with excessive pulmonary secre-tions. LEARNING OBJECTIVES After reading the preceding article and taking this test, you should be able to: 1. Identify patients at risk forexcess or retained pulmonary secretions. 2. Describe assessment findings related to excess or retained pulmonary secretions. 3. Describenursing interventions to help keep airways clear.

✄

1. To help maintain a clear airway, youshoulda. encourage prolonged coughing.b. keep the patient hydrated.c. limit environmental humidity.d. administer oxygen at a high flow rate.

2. Which condition results in excessivepulmonary secretions and airway con-striction?a. bronchiectasisb. Guillain-Barré syndromec. CFd. asthma

3. Which early assessment findings aremost likely in a patient who has anacute exacerbation of asthma?a. fever and nasal congestionb. wheezing and bradypneac. shortness of breath and tachycardiad. sneezing and hemoptysis

4. Which change in ABGs is found earlyin an asthma attack?a. increased pH levelb. increased PaO2 levelc. decreased bicarbonate leveld. increased PaCO2 level

5. Which respiratory disorder is char-acterized by chronic bronchial dilationand inflammation?a. bronchiectasis c. chronic bronchitisb. asthma d. viral pneumonia

6. Chronic bronchitis is characterized bya. reversible spasms of the bronchial tubes.b. an increased number of goblet cells

secreting excessive mucus.c. pooling of debris and secretions in the

alveoli.d. nerve conduction problems.

7. ABG analysis in a patient withadvanced CF commonly revealsa. metabolic acidosis.b. respiratory alkalosis.c. metabolic alkalosis.d. respiratory acidosis.

8. Which neuromuscular disease cancause respiratory muscle weakness anddecreased cough effectiveness?a. CFb. bronchiectasis c. myasthenia gravisd. bacterial pneumonia

9. Which assessment finding best sug-gests increased work of breathing?a. frequent coughingb. purulent nasal dischargec. deep inspirationsd. intercostal retractions

10. To assess a patient for fremitusa. inspect for diaphragmatic movement.b. palpate the chest wall while the patient

repeatedly says “99.”c. percuss the chest wall lightly.d. auscultate all lung lobes.

11. When assessing for adventitiousbreath sounds, ask the patient toa. exhale completely and stop breathing in

expiration. b. breathe in and out through the nose.c. breathe deeply through an open mouth.d. take quick, shallow breaths.

12. Teach patients with COPD who haveproblems with premature airway clo-sure to use which type of cough?a. assisted c. closed glottisb. huff d. pursed lip

13. Performing an abdominal thrust asyour patient inhales deeply and coughsis the best technique for a patient with a. chronic bronchitis.b. asthma.c. bronchiectasis.d. diaphragmatic paralysis.

14. Incentive spirometry can helpreopen alveoli and prevent a. bronchospasm.b. atelectasis.c. asthma.d. bronchiectasis.

15. Which mucoactive agent is indicatedto improve pulmonary function inpatients with CF?a. acetylcysteineb. codeinec. dornase alfad. guaifenesin

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