Anatomy: Lungs and Plurae

The Pleura •Serous layer of mesothelium that invest & enclose each lung •Visceral •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 membrane Left: Pleural reflection moves laterally from the midline then inferiorly up to the 6 th 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

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

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

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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

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 Pleural reflection pass: -lateral at 6 th rib

Gross Anatomy

Surgical pleurae/Pleural Cupola – covering in the apical area ‐  Right and left 

Lungs and Pleurae

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

•LDH 0.6 •Unilateral or Bilateral

Transudate (high pressure) Common causes: •Congestive heart failure •Renal insufficiency •Cirrhosis Treat the primary cause- Correct fluid  balance

Exudate

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) •

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Disorders of the Pleura

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 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

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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 •

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

Gross Anatomy

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Diagnosis is confirmed with chest xray •

•Treatment:  –Drainage with a chest tube

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

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

 –Oversewing of bleb  –Pleural scarification/abrasion

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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

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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

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-cardiopulmonary machine - lung surgery -in newborns: light and spongy -mediastinum in the middle - no communication bet. R&L lungs Trachea 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 4 th costal cartilages • •

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

Gross Anatomy

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

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

•Upper  •Middle: wedgeshaped •Lower  - 3 lobes middle lobe - most  anterior 

Surfaces 1.) Costal - curvature of the ribs 2.) Medial a. Mediastinal -contains root/hilum of lung -Cardiac impression  b. Vertebral 3.) Diaphragmatic -“base” Borders 1.)Anterior - Overlaps pericardium 2.)Posterior - Thick & rounded 3.)nferior - Thin & sharp - Costodiaphragmatic recess Trachea and Bronchi •Main bronchi (1°) @ divides into lobar bronchi

Lobes Left

Right

(2°)segmental bronchi (3°) •Right – wider, shorter   ─  more vertical > left Foreign Bodies Mucus membrane- last defense for foreign objects

Trachea - Midline tubular structure w/ 22 rings Carina -divides R&L  Pediatric pt - swallowed objects usually found in the right bronchi Mucus membrane

Gross Anatomy

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Lower 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

Lower

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superior basal

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superior basal

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medial basal

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anterior basal

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anterior basal

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lateral basal

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lateral basal

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 posterior basal

 posterior basal  Apico-posterior : merged as one segment  Superior-inf: lingular segment  •

Right ight (10 segme gments) ts) Left eft (8 segm segmen ents ts)) Upper Upper apical apico-posterior  •

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 posterior 

anterior  Middle lateral •

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anterior 

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superior 

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inferior 

medial

Gross Anatomy

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•Primary mode of treatment is medical (antibiotics)

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, 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 •

-Can involve a segment or a lot of segments  Hemoptysis =coughing of blood 

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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, 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

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

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

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

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

Gross Anatomy

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•Preserve as much lung tissue  Physiotherapy - promote drainage of sputum Endobronchial 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

Gross Anatomy

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