24yo male with no significant PMH presents with acute onset sharp chest pain located in the anterior lower right chest. Pain started this morning while walking to the bathroom. The pain is pleuritic and worse with exertion. Xray is shown below. What’s the diagnosis? (scroll down for answer)  

Answer: Spontaneous Pneumothorax

• Etiology
• Primary: occurs in patients without underlying pulmonary disease; classically in young, tall, thin males (often occurs at rest due to spontaneous rupture of subpleural apical bleb)
• Secondary: occurs in patients with underlying lung disease (asthma, COPD, CF)
• Iatrogenic: secondary to invasive procedures (subclavian central line) 
• Presentation
• often presents with SOB, pleuritic chest pain (can be gradual or acute depending on size and how quickly it occurs)
• exam will show decreased breath sounds on affected side
• Diagnosis
• CXR- often sufficient for diagnosis, will show radiolucent air/abscence of lung markings in periphery 
• CT- may be required for smaller PTX
• Management
• Small spontaneous PTX (< 20%) can be treated with supplemental O2 and repeat CXR at 4-6 hours to ensure no progression
• Larger PTX - treated with pigtail catheter vs tube thoracostomy 
• Tension PTX
• occurs due to positive pressure within the pleural space--> causes increased pressure --> mediastinal shift and impaired venous return
• presents with decreased breath sounds on affected side, tachycardia, hypotension
• CLINICAL DIAGNOSIS! 
• Treatment includes immediate needle decompression with 14g or 16g needle in 2nd intercostal space at midclavicular line, followed by tube thoracostomy 

References:

Richard W. Light, Merck Manuals. Vanderbilt University Medical Center. Jan 2021. https://www.merckmanuals.com/professional/pulmonary-disorders/mediastina...