Pleural Diseases

Why can pleural irritation result in referred shoulder pain?

The phrenic nerve innervates the parietal pleura

Disruption of the coupling between the parietal and visceral pleura by fluid produces an _________.

effusion

Disruption of the coupling between the parietal and visceral pleura by air produces a ________.

pneumothorax

What is the normal amount of fluid found in the pleural space?

5-15 mL

What are the four most common causes of pleural effusion?

• Heart failure

• Pneumonia

• Malignancy

• Pulmonary Embolism

What is the most common presenting symptom of a pleural effusion?

Dyspnea

How does the character of chest pain change as an effusion enlarges?

Improves as the pleural surfaces separate

What are the hallmark physical exam findings of a pleural effusion?

• Dullness to percussion

• Decreased tactile fremitus

What is the 1st line imaging test for suspected effusion?

Upright chest radiograph; requires 75-100 mL of fluid (lateral view) and 175-200 mL of fluid (frontal view)

What imaging modality is now the "standard of care" for confirming fluid and guiding thoracentesis.?

Point-of-care ultrasound (POCUS)

When is a diagnostic thoracentesis indicated?

For any new effusion without an obvious clinical cause

What is the "Gold Standard" for distinguishing transudative from exudative effusions?

Light's Criteria

Why might a transudative effusion be misclassified as an exudate?

Diuretics (concentrates pleural fluid)

What causes a transudative effusion?

Increased hydrostatic pressure or decreased oncotic pressure with normal capillary permeability.

What causes an exudative effusion?

Increased capillary permeability or decreased lymphatic clearance.

A ________ in a parapneumonic effusion indicates a need for drainage, similar to ____ glucose levels.

low pH (<7.2); low

An ______ is characterized by the presence of frank pus or a positive Gram stain or culture; drainage is always required.

empyema

A 65-year-old male with a history of heavy smoking presents with a unilateral effusion. Cytology is pending. What is the most likely diagnosis?

Malignant pleural effusion

What is the 1st line treatment for a symptomatic, recurrent malignant effusion?

Indwelling pleural catheter (IPC) or chemical pleurodesis

A ________ is caused by a disrupted thoracic duct (often surgery or trauma) and is identified by a milky appearance and elevated triglycerides.

Chylothorax

A _______ is grossly bloody; a pleural fluid hematocrit greater than 50% of the peripheral blood hematocrit is diagnostic.

Hemothorax

__________ occurs without trauma or underlying lung disease.

Primary Spontaneous Pneumothorax (PSP)

__________ occurs in the presence of known lung disease, most commonly COPD.

Secondary Spontaneous Pneumothorax (SSP)

Who is the "classic" patient for a Primary Spontaneous Pneumothorax?

Tall, thin, young male (age 10-30)

What is a "Catamenial" pneumothorax?

Associated with the menstrual cycle and thoracic endometriosis

Why is an SSP more dangerous than a PSP?

Limited pulmonary reserve

What classic symptom pairing occurs in 95% of pneumothorax patients?

• Chest pain

• Dyspnea

What physical exam finding distinguishes a pneumothorax from an effusion?

Hyperresonance to percussion

A trauma patient presents with acute distress, hypotension, and tracheal deviation away from the affected side. Dx?

Tension Pneumothorax

__________ is when air enters the pleural space on inspiration but cannot escape on expiration, progressively compressing the lung and reducing cardiac output.

Tension pneumothorax

What is the hallmark finding of a pneumothorax on a chest X-ray?

A visceral pleural line with absent lung markings

According to updated evidence, what is the management for a PTX with minimal symptoms?

Conservative management (observation)

What is the preferred 1st line management for a stable patient with mild symptoms and good support?

Ambulatory one-way valve device (Heimlich valve)

Where is the preferred needle decompression site for a tension pneumothorax?

4th or 5th intercostal space, anterior axillary line

What is the definitive treatment that should follow a needle decompression?

Tube thoracostomy

The single most modifiable risk factor for pneumothorax recurrence is ________.

Smoking

What is "Hamman’s Sign" and what does it indicate?

A "crunching" sound over the heart; pneumomediastinum

What complication can occur if a hemothorax or complicated effusion is not adequately evacuated?

Fibrothorax

When is a referral to thoracic surgery indicated for a pneumothorax?

Recurrence, persistent air leak (> few days), or SSP

Why shouldn't a patient's symptomatic improvement be mistaken for radiographic resolution?

Symptoms often partially improve within 24 hours regardless of PTX status

What is the recurrence rate for a PSP after the first episode?

Approximately 50%

What is the management pivot for pneumothorax in modern practice?

Symptoms and stability, not size.