Implementation of 300-mL Rule for Management of Traumatic Hemothorax

Background: Traumatic hemothorax (HTX) is often managed with tube thoracostomy (TT); however, TT carries a high complication rate. In 2017, a guideline was implemented at our Level I trauma center to observe traumatic HTX 300 mL or less in patients who are hemodynamically stable. We hypothesized that this guideline would decrease TT placement without increasing observation failure rates.

Study design: This was a single-center retrospective review of all adult patients admitted with an HTX on CT before (2015 to 2016) and after (2018 to 2019) the guideline implementation. Exclusion criteria were TT placement before CT scan, absence of CT scan, death within 5 days of admission, and a concurrent pneumothorax more than 20 mm. HTX volume was calculated using CT scan images and Mergo's formula: V = d2 × L (where V is the volume, d is the depth, and L is the length). The primary outcome was observation failure, defined as the need for TT, video-assisted thoracoscopic surgery, thoracotomy after repeat imaging or worsening of symptoms, and pulmonary morbidity.

Results: A total of 357 patients met inclusion criteria, of whom 210 were admitted after guideline implementation. No significant differences in baseline demographics, comorbidities, or injury characteristics across both cohorts were observed. The postimplementation cohort had a significant increase in observation rate (75% vs 59%) and a decrease in TT placement (42% vs 57%). The postimplementation group had a statistically significant shorter hospital (6 vs 8 days) and ICU (2 vs 3 days) length of stay. No significant differences in observation failure, pulmonary complications, 30-day readmission, or 30-day mortality were observed across both cohorts.

Conclusions: The implementation of the 300-mL guideline led to a decrease in TT placement without increasing observation failure or complication rates.