The Time Course of Recurrent Pneumothorax Development after Thoracostomy Tube Removal in Trauma Patients: An Ultra-Portable Ultrasound Study (UPUS Trial)

Introduction: Recurrent pneumothorax (rPTX) is one of the most common complications after thoracostomy tube (TT) removal, although there is little data regarding when rPTX develops. Consequently, the timing of repeat imaging or duration of observation after TT removal remains variable among providers and centers. Using an ultra-portable ultrasound (UPUS), we sought to determine when post-TT rPTX occur. Methods: This is a single-center, exploratory prospective study of adult trauma patients with TT. UPUS examinations were performed by two clinically trained researchers using the Butterfly iQ+TM Ultrasound each hour for 6 hours after TT removal. Three intercostal spaces (ICS) were evaluated during each exam. rPTX was diagnosed if a lung point or lack of lung sliding was noted in 1 or more ICS, and was considered a significant rPTX if present in 2 or more ICS. Results: A total of 20 patients were enrolled. Post-TT rPTX was identified at one or more hourly ultrasounds in nine patients (45%), though only seven (78%) were evident at hour 6. Four rPTX were apparent at hour 1, and all remaining rPTX were present by hour 3. Two patients required TT replacement, both of whom had a significant rPTX identified at hour 1. Conclusion: Recurrent PTXs after TT removal appear to develop within three hours, with significant rPTX being detected as early as hour 1. The size of rPTX appears to stabilize by hour four. In the absence of clinical symptoms, repeat imaging or observation of non-significant rPTX beyond 4 hours may not add clinical benefit.