ABSTRACT: BACKGROUND:Damage control laparotomy (DCL) is intended to limit deleterious effects from trauma-induced coagulopathy. DCL has been associated with mortality reduction, but may increase complications including sepsis, abscess, respiratory failure, hernia, and gastrointestinal fistula. We hypothesized that (1) DCL incidence would vary between institutions; (2) mortality rates would vary with DCL rates; (3) standard DCL criteria of pH, international normalized ratio, temperature and major intra-abdominal vascular injury would not adequately capture all patients. METHODS:Trauma patients at 12 Level 1 North American trauma centers were randomized based on transfusion ratios as described in the Pragmatic, Randomized Optimal Platelet and Plasma Ratios trial. We analyzed outcomes after emergent laparotomy using a mixed-effects logistic model comparing DCL versus definitive surgical management with random effect for study site. Primary outcomes were 24-hour and 30-day mortality. RESULTS:Three hundred twenty-nine patients underwent emergent laparotomy: 213 (65%) DCL and 116 (35%) definitive surgical management. DCL rates varied between institutions (33-83%), (p = 0.002). Median Injury Severity Score (ISS) was higher in the DCL group, 29 (interquartile range, 13-34) versus 21 (interquartile range, 22-41) (p < 0.001). Twenty-four-hour mortality was 19% with DCL versus 4% (p < 0.001); 30-day mortality was 28% with DCL versus 19% (p < 0.001). In a mixed-effects model, ISS and major intra-abdominal vascular injury were correlates of DCL (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.02-1.07 and OR, 2.7; 95% CI, 1.4-5.2). DCL was not associated with 30-day mortality (OR, 2.33; 95% CI, 0.97-5.60). Correlates included ISS (OR, 1.06; 95% CI, 1.02-1.09), PRBCs in 24 hours (OR, 1.10; 95% CI, 1.03-1.18), and age (OR, 1.04; 95% CI, 1.01-1.06). No significant mortality difference was detected between institutions (p = 0.63). Sepsis and VAP occurred more frequently with DCL (p < 0.05). Eighty percent (135/213) of DCL patients met standard criteria. CONCLUSION:Although DCL utilization varied significantly between institutions, there was no significant mortality difference between centers. This finding suggests tempering DCL use may not decrease mortality, but could decrease related complications. LEVEL OF EVIDENCE:Therapeutic study, level III.