Pulmonology · Pleural Disease
The facts most likely to be tested
Press 1–5 to rate · ↑↓ to navigate
Primary spontaneous pneumothorax classically strikes a tall, thin male smoker aged 10-30 from ruptured apical subpleural blebs, while secondary type occurs with underlying COPD.
Tension pneumothorax is a clinical diagnosis with tracheal deviation away from the affected side, hypotension, and JVD requiring immediate needle decompression; ATLS 10th edition now recommends the 5th intercostal space at the anterior/mid-axillary line in adults (2nd ICS midclavicular line remains an alternative).
Exam shows unilateral pleuritic chest pain, hyperresonance to percussion, decreased breath sounds, and decreased tactile fremitus on the affected side.
The initial diagnostic test is an upright PA chest radiograph showing a visceral pleural line with absent peripheral lung markings.
Point-of-care ultrasound reveals absence of lung sliding and the barcode (stratosphere) sign on M-mode; chest CT is the gold standard for small or recurrent cases.
Small stable primary pneumothoraces (<3 cm from apex) get observation plus 100% supplemental oxygen to speed resorption; large or symptomatic cases need needle aspiration or chest tube thoracostomy.
Recurrence is high at 30-50% after a first episode, and recurrent or bilateral disease warrants definitive VATS with pleurodesis.
Vignette unlocked
A 22-year-old tall, thin man presents with sudden-onset right-sided pleuritic chest pain and dyspnea that began while he was at rest. He smokes half a pack of cigarettes daily and has no other medical history. On exam, he has hyperresonance to percussion and decreased breath sounds over the right hemithorax. He is hemodynamically stable, and an upright PA chest radiograph shows a right visceral pleural line with a 1.5 cm rim of air and no mediastinal shift.
Which of the following is the most appropriate next step in management?
Observation with 100% supplemental oxygen
A small (<3 cm), stable primary spontaneous pneumothorax in a hemodynamically stable patient is managed with observation and high-flow oxygen, which accelerates pleural air resorption. Needle decompression is reserved for tension physiology, and chest tubes are reserved for large or symptomatic pneumothoraces.
Full handout
High yield triage
Etiology / Epidemiology
Primary type classically affects tall, thin males aged 10-30 who smoke, while secondary type occurs in older patients with underlying lung disease, most commonly COPD.
Clinical Manifestations
Sudden onset of unilateral pleuritic chest pain and dyspnea, with hyperresonance to percussion and decreased breath sounds; tension pneumothorax presents with tracheal deviation and hemodynamic instability.
Diagnosis
Initial test is an upright PA chest radiograph showing a visceral pleural line with absent peripheral lung markings; ultrasound shows an absence of lung sliding.
Treatment
Small, stable primary pneumothoraces get observation with 100% supplemental oxygen; large or symptomatic cases require needle aspiration or chest tube thoracostomy; tension physiology demands immediate needle decompression.
Prognosis
High recurrence rate of 30-50% after the first episode; recurrent or bilateral cases require definitive surgical management with VATS and pleurodesis.
Full handout
Epidemiology & Etiology
Primary spontaneous pneumothorax (PSP) classically affects tall, thin males aged 10-30 years, heavily linked to smoking and connective tissue disorders like Marfan syndrome. Secondary spontaneous pneumothorax (SSP) occurs in older patients with preexisting lung architecture damage, most commonly COPD, but also cystic fibrosis, Pneumocystis jirovecii pneumonia, and tuberculosis. Catamenial pneumothorax is a rare etiology associated with thoracic endometriosis, typically occurring within 72 hours of menses onset.
Pertinent Anatomy
The pleural space normally maintains negative intrapleural pressure to keep the lungs expanded against the chest wall. The visceral pleura covers the lung parenchyma, while the parietal pleura lines the inner thoracic cavity. Rupture of a visceral pleural defect allows air to enter this potential space, equalizing pressure and causing the lung parenchyma to collapse inward.
Pathophysiology
In PSP, apical subpleural blebs or bullae rupture, allowing alveolar air to escape into the pleural space. This abolishes the normal negative intrapleural pressure, leading to partial or complete lung collapse driven by inherent elastic recoil. If the tissue defect acts as a one-way valve, air enters during inspiration but cannot exit, rapidly accumulating intrapleural volume. This creates a tension pneumothorax, which compresses the contralateral lung and obstructs venous return to the heart, ultimately causing fatal obstructive shock.
Clinical Manifestations
Patients typically present with acute onset of ipsilateral pleuritic chest pain and dyspnea. Physical exam reveals decreased tactile fremitus, hyperresonance to percussion, and diminished breath sounds on the affected side. A tension pneumothorax presents with tracheal deviation to the contralateral side, jugular venous distension, and hypotension. Suspect tension physiology in any patient who becomes hemodynamically unstable.
Diagnosis
The initial test of choice is an upright PA chest radiograph, which classically demonstrates a discrete visceral pleural line with a peripheral space lacking bronchovascular markings. Point-of-care ultrasound (POCUS) is highly sensitive, demonstrating an absence of lung sliding and the pathognomonic barcode sign (or stratosphere sign) on M-mode. Chest CT is the gold standard for detecting small pneumothoraces and identifying underlying blebs, but is reserved for complex, secondary, or recurrent cases.
Treatment
For a stable, small PSP (<3 cm from apex to cupola), the first-line approach is observation and administration of 100% supplemental oxygen, which accelerates pleural air resorption. For a large or symptomatic PSP, perform needle aspiration or insert a small-bore chest tube. SSP generally requires chest tube thoracostomy and hospital admission. A tension pneumothorax is a clinical diagnosis requiring immediate needle decompression at the 2nd intercostal space, midclavicular line (or 5th ICS anterior axillary line) before obtaining any imaging.
Prognosis
Recurrence is extremely common, occurring in up to 30-50% of patients after the first episode, with the highest risk in continued smokers. Video-assisted thoracoscopic surgery (VATS) with pleurodesis (mechanical or chemical using talc or tetracycline) is indicated for recurrent pneumothorax, bilateral pneumothorax, or incomplete lung expansion after chest tube placement. Patients must avoid air travel and scuba diving until definitive clearance is given due to pressure changes.
Differential Diagnosis
1. Myocardial Infarction: Presents with crushing substernal pain and ST-segment elevations or elevated troponins.
2. Pulmonary Embolism: Sudden dyspnea and pleuritic pain but features a normal chest X-ray or Hampton hump, diagnosed via CT pulmonary angiography.
3. Pleurisy: Sharp pleuritic pain often with a pleural friction rub, but lung markings extend fully to the periphery on radiography.
4. Aortic Dissection: Sudden tearing chest pain radiating to the back with a widened mediastinum on chest X-ray.