Which test is used to diagnose a pneumothorax most commonly?

Which test is used to diagnose a pneumothorax most commonly?

• A. PA/lateral chest X-ray
• B. ABG showing hypoxia
• C. ECG axis deviation
• D. CT chest to define bullous disease

Answer: (A)

When a pneumothorax is suspected, the imaging study most commonly used to confirm it is a chest radiograph with two views (PA and lateral). This provides a quick, widely available, and typically sufficient way to visualize air in the pleural space. On an upright PA/lateral film you look for a visceral pleural line with a lack of lung markings peripheral to it, most conspicuously at the apex. Small pneumothoraces can be subtle, especially if the film is not taken with the patient upright, but this combination of views remains the standard initial test because it balances speed, accessibility, and diagnostic yield for the majority of stable patients. CT chest can detect smaller or occult pneumothoraces with higher sensitivity, and ultrasound at the bedside can rapidly identify pneumothorax in many settings, but neither is used as the routine initial test in most cases. An ABG may show hypoxia related to a pneumothorax, but it does not visualize air in the pleural space, so it cannot diagnose the condition. ECG axis deviation is unrelated to diagnosing a pneumothorax.

When a pneumothorax is suspected, the imaging study most commonly used to confirm it is a chest radiograph with two views (PA and lateral). This provides a quick, widely available, and typically sufficient way to visualize air in the pleural space. On an upright PA/lateral film you look for a visceral pleural line with a lack of lung markings peripheral to it, most conspicuously at the apex. Small pneumothoraces can be subtle, especially if the film is not taken with the patient upright, but this combination of views remains the standard initial test because it balances speed, accessibility, and diagnostic yield for the majority of stable patients.

CT chest can detect smaller or occult pneumothoraces with higher sensitivity, and ultrasound at the bedside can rapidly identify pneumothorax in many settings, but neither is used as the routine initial test in most cases. An ABG may show hypoxia related to a pneumothorax, but it does not visualize air in the pleural space, so it cannot diagnose the condition. ECG axis deviation is unrelated to diagnosing a pneumothorax.