Negative laparotomy rates and outcomes following blunt traumatic injury in the United States.

introductionExploratory laparotomy remains the mainstay of treatment following blunt abdominal trauma. However, the decision to operate can be difficult in hemodynamically stable patients with unreliable physical exams or equivocal imaging findings. The risk of a negative laparotomy and the subsequent complications must be weighed against the potential morbidity and mortality of a missed abdominal injury. Our study aims to evaluate trends and the effect of negative laparotomies on morbidity and mortality in adults with blunt traumatic injuries in the United States.

methodsWe reviewed the National Trauma Data Bank (2007-2019) for adults with blunt traumatic injuries who underwent an exploratory laparotomy. Positive or negative laparotomy of abdominal injury was compared. We performed bivariate analysis and a modified Poisson regression to estimate the effect of negative laparotomy on mortality. A sub-analysis of patients who underwent computed tomography (CT) of the abdomen and pelvis was performed.

results92,800 patients met the inclusion criteria of the primary analysis. Negative laparotomy rates were 12.0% in this population, down-trending throughout the study. Negative laparotomy patients had a significantly higher crude mortality (31.1% vs. 20.5%, p < 0.001), despite lower injury severity scores (20 (10-29) vs. 25 (16-35), p < 0.001) than positive laparotomy patients. Patients that underwent negative laparotomy had a 33% higher risk for mortality (RR1.33, 95% CI 1.28-1.37, P < 0.001) than positive laparotomy patients after adjusting for pertinent covariates. Patients that underwent CT abdomen/pelvis imaging (n = 45,654) had a lower rate of negative laparotomy (11.1%) and decreased difference in crude mortality (22.6% vs. 14.1%, p < 0.001) compared to positive laparotomy patients. However, the relative risk for mortality remained high at 37% (RR 1.37, 95% CI 1.29 - 1.46, p < 0.001) for this sub-cohort.

conclusionNegative laparotomy rates in adults with blunt traumatic injuries are trending down in the United States but remains substantial and may show improvement with increased use of diagnostic imaging. Negative laparotomy has a relative risk for mortality of 33% despite lower injury severity. Thus, surgical exploration in this population should be thoughtfully undertaken with appropriate evaluation via physical exam and diagnostic imaging to prevent unnecessary morbidity and mortality.