Pressure-dependent persistent air leak in a patient with secondary spontaneous pneumothorax.

An air leak lasting more than 5-7 days (persistent air leak, PAL) can complicate up to 40% of patients with secondary spontaneous pneumothorax. Chronic obstructive pulmonary disease is the most common cause of secondary spontaneous pneumothorax, and early surgical intervention has been recommended for patients with PAL. Bullectomy or blebectomy with concomitant mechanical pleurodesis by medical thoracoscopy or video assisted thoracoscopic surgery is considered definitive therapy. Unfortunately, the perioperative course following lung resection can also be complicated by air leaks leading to worse clinical outcomes. Post lung resection air leak can be pressure independent or pressure dependent (also known as drainage-related air leak). The distinction between these two entities is crucial as the management varies drastically. Pleural manometry may play an important role in the early diagnosis of pressure-dependent PAL preventing further unnecessary surgical procedures from being performed.