anatomy: lungs and plurae

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The Pleura•Serous layer of mesothelium that invest & enclose each lung•Visceral pleura – lines the lung itself•Parietal pleura – lines the chest wall•Pleural cavity – contains a layer of serous pleural fluid for lubrication (100mL produced and absorbed daily )

THE PARIETAL PLEURA •Costal pleura – in the ribs•Mediastinal pleura•Diaphragmatic pleura – on top of the diaphragm•Cervical pleura/suprapleural membraneLeft:

• Pleural reflection moves laterally from the midline then inferiorly up to the 6th costal cartilage

• Left lung is more deeply indented by the cardiac notch

Right:• Pleural reflection continues inferiorly

from 4th to 6th costal cartilage• Lung parallels pleural reflection closely

Pleural reflection pass:-lateral at 6th rib

-reach the Midclavicular line at 8th costal cartilage-10th rib at Midaxillary line-12th rib at the scapular line

Inferior Margin of the lungs reach:-Midclavicular line at 6th rib-Midaxillary line at 8th rib-Scapular line at 10th rib

Clinical Importance:Posteriorly the pleural may go beyond the costal margin – Prone to injury during abdominal surgery During kidney surgery, injury to the pleura may occur and cause air to enter into the thoracic or pleural cavity

Surgical pleurae/Pleural Cupola – covering in the apical area

‐ Right and left

GROSS KARLOS R. ALETA, M.D.

LUNGS AND PLEURAE

Gross Anatomy Lungs and Pleurae

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‐ Most superior part is below the 1st rib but never above the neck of the 1st rib

‐ Extends in the superior thoracic aperture to go to the neck

‐ Dome shaped groove‐ Because of position,if there is injury to

neck (laceration, gunshot wound, ice pick), the pleural may also be injured and also the underlying lung.

Pleura reflection ends 2 finger breaths above the most inferior costal margin

Pleural Recesses•On full inspiration – lungs fill up cavities•Quiet respiration – 3 parts not occupied•Area of acute P R – “parietal on parietal pleura reflection”

-R&L Costodiaphragmatic recesses-Costomediastinal Recess

Disorders of the Pleura

Hydrothorax-fluid accumulation in the thorax or pleural cavity-can be anything ie. blood, chyle, pus-as fluid increases the lungs will be more collapsed and near the hilum-if you want to breath you can’t utilize the whole parenchyma because its squished-the fluid prevents expansion

Classic signs:•Dullness on percussion•Decreased breath sounds•Mediastinal displacement - (organs are pushed to the other side)•Transudate vs Exudate•Total protein 0.5

•LDH 0.6•Unilateral or Bilateral

Transudate (high pressure)

Exudate

Common causes:•Congestive heart failure•Renal insufficiency •CirrhosisTreat the primary cause- Correct fluid balance

Common causes:•Infection•Malignancy•Treatment:•Drainage•Antibiotics (for parapneumonic effusions and empyemas)•Pleurodesis (for malignant effusions)

Thoracentesis• Draining the fluid in the thorax w/ a

needle• Patient’s back to Physician w/ elbows

forward & raised 90°• Allows to move scapula tip laterally –

away from field of puncture• Insert needle on appropriate ICS~top of

rib (decrease chances of hitting the VAN bundle)

Pneumothorax-normal parenchyma balloons

• Usually due to rupture of subpleural cyst or bulla

• Air in the pleural space• Primary: it just happened• Secondary: pt has an already existing

lung problem• Pt is usually dyspneic, breath sounds

absent or decreased• Other PE…??? Tachypnia, eyes are

enlarged, engorged neck vein


LUNGS AND PLEURAE


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• Diagnosis is confirmed with chest xray

•Treatment:–Drainage with a chest tube

For persistent air leaks or recurrences:–Video Assisted Thoracoscopic Surgery (VATS)–Thoracotomy

–Oversewing of bleb–Pleural scarification/abrasion

Hemothorax• Accumulation of blood in the thorax• Usually seen in chest trauma, blunt or

penetrating• Anticoagulant therapy• Treatment• Chest tube drainage• For trauma cases: Thoracotomy for

control of hemorrhage (>200ml/hr drainage)

• Blood can rise and fill upthe whole lungs until it collapse.

Empyema Thoracis - pus• Develops from untreated or inadequately

treated parapneumonic effusions• Post op patients (lung resections or pleural

procedures)*pus has its own lining• Empyemectomy - removing the pus as a

whole• Decortication – prolonged cases; pus has

hardened; stripping the lining out of the lung in order for the lungs to expand again

Chylothorax • Accumulation of lymph in the pleural cavity• Tumor• Injury to Thoracic Duct (the aqueduct of the

lymph)

• If persistent beyond 3 to 4 weeks• Ligation of Thoracic Duct• Talc Pleurodesis

Pleuroperitoneal shunt – direct chyle to the peritoneum to the abdomen to be absorbed

The Lungs• Essential organs of respiration• Normally light, soft & spongy• Left & Right separated fr @ other by

mediastinum• Attached: heart & trachea by the “root of the

lung”Inferior Pulmonary ligament

-cardiopulmonary machine - lung surgery-in newborns: light and spongy-mediastinum in the middle - no communication bet. R&L lungsTrachea connects to the lung itself

Surface Anatomy• Cervical pleurae & apices• Pass through superior thoracic aperture

into the supraclavicular fossa• Anterior borders of lungs• Adjacent to anterior lines of reflection of

the parietal pleura up to level of 4th costal cartilages

FissuresOblique - extends from spinous process of T2 vertebra to 6th costal cartilage- Coincides w/3 vertebral border of scapula when arm is elevatedHorizontal- is at the 4th rib & costal cartilage anteriorly


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Lobes

Left Right

•Superior: cardica notch,lingula•Inferior- 2 lobesLingula- homologue of the middle lobe of the right

•Upper•Middle: wedge-shaped•Lower - 3 lobesmiddle lobe - most anterior

Surfaces1.) Costal - curvature of the ribs2.) Medial

a. Mediastinal -contains root/hilum of lung

-Cardiac impressionb. Vertebral

3.) Diaphragmatic -“base”

Borders1.)Anterior - Overlaps pericardium2.)Posterior - Thick & rounded3.)nferior - Thin & sharp

- Costodiaphragmatic recess

Trachea and Bronchi•Main bronchi (1°)

@ divides into lobar bronchi

(2°)segmental bronchi (3°)•Right – wider, shorter

─ more vertical > leftForeign BodiesMucus membrane- last defense for foreign objects

Trachea - Midline tubular structure w/ 22 ringsCarina -divides R&LPediatric pt - swallowed objects usually found in the right bronchiMucus membrane


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Brochopulmonary Segment•Pyramidal-shaped lung segment•Largest subdivision of a lobe•Supplied independently

-Segmental bronchus-Supplied by 3° branch of pulmonary artery -drained by intersegmental parts of pulmonary vein

•Named acc to segmental bronchus supplying it•Surgically resectable

Right (10 segments) Left (8 segments)Upper

• apical

• posterior

• anterior

Upper• apico-posterior

• anterior

• superior

• inferiorMiddle

• lateral

• medial

Lower• superior basal

• medial basal

• anterior basal

• lateral basal

• posterior basal

Lower• superior basal

• anterior basal

• lateral basal

• posterior basal

Apico-posterior : merged as one segmentSuperior-inf: lingular segment


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Disorders of the Lungs

Lung Cancer• Most common malignant tumor affecting

males & females• Smoking• What do we know?

Most cases are caused by the environment, primarily from tobacco exposure

Absent smoking, lung cancer would be uncommon

Genes have a role in susceptibility, but which ones and the extent is unclear

Causes:-Smoking-Radon gas- Asbestos-Recurring lung inflammation-Lung scarring secondary to tuberculosis-Family history-Exposure to other carcinogens such as bis(chloromethyl)ether, polycyclic aromatic hydrocarbons, chromium, nickel and organic arsenic compounds

Goal of Treatment:–Identify tumor, get tissue diagnosis–Determine the stage of the disease–Surgery–Chemotherapy–Radiation Therapy

Bronchiectasis•Persistent abnormal dilatation of the bronchi generally at the subsegmental level•Localized or diffuse – medium-sized airways•Congenital or acquired•Chronic cough with purulent sputum•50% present with hemoptysis

•Primary mode of treatment is medical (antibiotics)

-Can involve a segment or a lot of segmentsHemoptysis =coughing of blood

Pathophysiology:•Impaired airway defense & ↓ Immunologic mechanisms ~permit colonization & infection•Bacteria & inflammatory cells elaborate proteolytic & oxidative molecules•Progressively destroy muscular & elastic components ~ fibrous tissue

- Chronic airway inflammation- Airway w/ thick purulent secretions

•↑ vascularity, hypertrophied vessels

Clinical Presentation:•Daily persistent cough + purulent sputum production ~correlate w/ extent•↑ symptoms & respiratory impairment ~ ↑ airway obstruction•Hemoptysis – chronically inflamed friable airway mucosa

-Massive ~ erosion of hypertrophied bronchial arteries =fatal

Diagnostics:•Chest CT– x-section bronchial architecture•CXR – lung hyperinflation, bronchiectatic cysts,dilated thich-walled bronchi from hila•Sputum culture•Spirometry – severity of airway obstruction

Management:•Optimize secretion clearance•Use of bronchodilators•Correct reversible underlying causes•Chest physiotherapy•Acute exacerbations ~ broad-spectrum antiBx•Surgical resection – refractory to Med tx


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•Preserve as much lung tissuePhysiotherapy - promote drainage of sputum

Endobronchial tumors can occur in any part of the bronchial tree-Endoscopy

-Bulky tumors- can cause obstruction--mechanical resection + laser if needed--tracheal resection: resect then connect

_END


LUNGS AND PLEURAE


anatomy: lungs and plurae

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