A multicenter retrospective evaluation of treatment variation in patients with a blunt traumatic pneumothorax; noninvasive treatment versus tube thoracostomy (CONSTRAIN-Retro)

BACKGROUND: There is no clear consensus to which extent noninvasive treatment can be used with regard to posttraumatic pneumothorax size. This results in treatment variation among physicians. This study primarily aimed to examine the current treatment variation in the management of unilateral pneumothorax after blunt trauma, varying in size. Secondarily, clinical outcomes were evaluated in patients with the greatest treatment variation. METHODS: This multicenter retrospective cohort study included adult patients admitted with unilateral pneumothorax following blunt trauma between January 1, 2021, and December 31, 2022. The primary outcome measure was the type of index treatment, and secondary outcome measures were secondary tube thoracostomy (TT), adverse events, and hospital length of stay. RESULTS: Of 275 eligible patients in the overall study population, 126 (45.8%) patients received noninvasive treatment, and 149 (54.2%) underwent TT. Treatment variation was greatest for pneumothorax sizes of 15% to 50%, defined as medium-sized pneumothorax (36.6% noninvasive and 63.4% TT). Secondary TT was performed in 14 (29.2%) patients with medium-sized pneumothorax. Hospital length of stay was shorter for the noninvasive group with medium-sized pneumothorax compared with the TT group, although this finding did not reach statistical significance after IPTW analysis (4 d vs. 5 d; p =0.313). No statistical difference was found for overall complications (32.8% vs. 30.2%; OR: 1.14 (95% CI: 0.40–3.28); p =0.811). CONCLUSIONS: In this study, noninvasive treatment was used in 45.8% of patients for managing pneumothorax after blunt trauma. Treatment variation was mainly seen for patients with pneumothorax sizes of 15% to 50%. Noninvasive treatment in patients with such medium-sized pneumothorax was associated with similar hospital length of stay and complication rates compared with TT, and deemed a safe treatment strategy. ( J Trauma Acute Care Surg . 2026;100: 863–870. Copyright © 2025 The Author(s). Published by Wolters Kluwer Health, LLC. on behalf of the American Association for the Surgery of Trauma.) LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.