L14 Pleural Disease

• Mesothelial cells (mesoderm origin)
• Connective tissue (blood and lymph vessels)
• 1-2 cells thick

• Visceral Pleura:
• -covers lung
• -separates lobes of lung from each other

• Parietal Pleura:
• -lines chest wall, diaphragm and mediastinum
• -stomata between mesothelial cells
• -sensory nerve endings

-potential space

~10 mL of pleural fluid to provide lubrication during respiration (made and drained by parietal pleura)

-Negative pressure created by outward force of chest wall and inward force of lung

• Visceral Pleura
• -supplied by bronchial artery
• -drained by pulmonary veins

• Parietal Pleura
• -supplied by intercostal artery
• -drained by systemic veins
• -stomata --> lymphatics

Production = Absorption (15-20mL/day)

• Balance between:
• -hydrostatic forces
• -oncotic forces
• -membrane permeability
• -(Starling Equation)

• 1. Transudate
• -imbalance of hydrostatic pressure
• -imbalance of oncotic pressure
• *often secondary to non-pulmonary pathophysiology

• 2. Exudate
• -increase in mesothelial or capillary permeability
• -often inflammatory

• 1. Congestive Heart Failure
• -increased pulmonary venous pressure
• -liquid leaks out of pulmonary capillaries into interstitium, then into pleural space

• 2. Hyperproteinemia
• -reduced oncotic pressure
• -nephrotic syndrome

• 3. Excessive Salt/Water intake
• -hospitalized patients

• 4. Hepatic hydrothorax
• -portal HTN --> ascites
• -ascites pass through diaphragm down pressure gradient (often R-sided)

• 5. Pulmonary Embolism
• -without infarction

• 1. Malignancy
• -direct involvement of pleural space
• -lymphatic obstruction of drainage

• 2. Infection
• a) TB
•      -cavitary rupture
• b) Pneumonia
•      -parapneumonic effusion (sterile)
•      -empyema (infected)

• 3. Autoimmune CT Disease
• -SLE
• -RA

4. Post-CABG

• 5. Sympathetic Effusion
• -pancreatitis
• -subphrenic abscess

• 6. Hemothorax
• 7. Esophageal rupture
• 8. PE with infarction
• 9. Benign asbestos-related pleural effusion (BAPE)

• Symptoms:
• 1. Pleuritic Pain
• 2. Fever (if infectious)
• 3. Dyspnea (if large)
•      -hypoxemia (if large)
•      -hypercapnia very rare
• 4. Asymptomatic

• Physical Exam:
• 1. Dullness (clavicle trick)
• 2. Decreased breath sounds
• 3. Egophony at superior edge of effusion
• 4. Pleural friction rub
• 5. Tracheal shift (if under high pressure)
• 6. Asymmetric chest rise

• 1. Imaging (CXR, CT, U/S)
• 2. Invasive Procedures

• 1. CXR
• -blunting of phrenic angles
• -meniscus (tracking along lateral wall)
• -straight lines if hydropneumothorax

• 2. CT
• -small pleural effusion

• 3. U/S
• -low echogenicity
• -"dark" pockets

• 1. Thoracentesis
• 2. Tube thoracostomy (chest tube)
• 3. Pleuroscopy
• 4. Video-assisted thoracic surgery (VATS)
• 5. Closed pleural bx (good for TB)

• Light's Criteria:
• 1. LDH
• -pleural > 0.6 Serum
• -pleural > 2/3 ULN Serum
• 2. Total Protein
• -pleural > 1/2 serum

** only need to meet 1/3 criteria to = exudate

• Other Tests:
• -cell count
• -pH
• -glucose (infections)
• -TGs
• -Amylase (ruptured esophagus)
• -Serum-pleural albumin gradient (diuresis)

• -fibrous bands of tissue
• -can lead to effusions that "defy gravity"
• -seen in long standing effusions (almost always exudative)

• Commonly seen in:
• -malignant effusions
• -prior empyema
• -prior hemothorax

• 1. Treat the underlying cause
• 2. Diuresis

• 3. Thoracentesis
• -short term tx of sx

4. Tube thoracostomy

• 5. Surgery with decortication
• -esp for loculations
• 6. Pleurodesis
• -instill irritating agents (talc, tetracycline derivative) into pleural space
• -induces inflammation and scars visceral and parietal pleura together

• 7. Pleur X catheter
• -recurrent (esp due to malignancy)
• -don't need to go into hospital

• 1. Air entry from outside the body (parietal pleura)
• -trauma
• -iatrogenic (tubes, catheters, incisions)
• -hydropneumothorax with lung entrapment

• 2. Air entry from within the body (visceral pleura)
• -ruptured bleb, bulla, cyst
• -esophageal rupture (achalasia)
• -bronchial fracture (hit steering wheel in MVA)
• -spontaneous primary pneumothorax

Tension pneumothorax can occur with mechanical ventilation

-consequences range from none to acute cardiovascular collapse

-accumulation of substantial amount of air can collapse underlying lung parenchyma

• -usually under atmospheric pressure
• -if under positive pressure = tension pneumothorax
• -may lead to shifting of the mediastinum and trachea

• Cardiovascular Collapse
• -in extreme cases
• -fall in CO and BP
• -due to inhibition of venous return

• Symptoms:
• -sharp, acute onset chest pain
• -minimal discomfort
• -pleuritic pain
• -dyspnea
• -asymptomatic
• -SICK (hypoxemia, hypotension, midline shift)

• Physical Exam:
• -decreased breath sounds
• -hyperresonance (tympany)
• -tracheal deviation (tension)
• -hypotension (tension0
• -hypoxemia

-Most resolve spontaneously (pressure in pleural space higher than pressure in mixed venous blood)

• 1. 100% FiO2 by face mask
• -washes nitrogen out from blood creating a diffusion gradient for the gas in the pleural space

• 2. Needle Decompression
• -2nd intercostal space
• -emergency only

• 3. Thoravent
• -trochar with catheter

4. Pigtail Chest Tube

5. Surgical or large bore chest tube

6. Pleurodesis