Nephrectomy is Associated with Increased Mortality after Renal Trauma: An Analysis of the National Trauma Data Bank from 2007-2016

Purpose:The majority of high grade renal trauma can be managed conservatively. However, nephrectomy is still common for acute management. We hypothesized that when controlling for multiple injury severity measures, nephrectomy would be associated with increased mortality.Materials and Methods:We identified high grade renal trauma patients from the National Trauma Data Bank® from 2007-2016. Exclusion criteria were age <18 years, severe head injury and death within 4 hours of admission. We performed conditional logistic regression analysis to determine if nephrectomy was independently associated with mortality, controlling for age, gender, race/ethnicity, mechanism of injury, shock, blood transfusion, Glasgow Coma Scale, Revised Trauma Score and Injury Severity Score. Interaction was measured for mechanism of injury and shock with mortality.Results:We identified 42,898 patients with high grade renal trauma (grade III-V), of whom 3,204 (7.5%) underwent nephrectomy. Unadjusted mortality was 16.6% in nephrectomy vs 5.7% in nonnephrectomy patients. In multivariable logistic regression, nephrectomy was associated with 82% increased odds of death (OR 1.82, 95% CI 1.63-2.03, p <0.001). Other significant associations with death included age, nonWhite race, penetrating mechanism, hypotension, blood transfusion, lower Glasgow Coma Scale, lower Revised Trauma Score and higher Injury Severity Score. The association between nephrectomy and death did not differ by mechanism of injury. However, it was slightly attenuated in patients presenting in shock.Conclusions:In the National Trauma Data Bank, nephrectomy is independently associated with increased risk of mortality after adjusting for patient demographics, injury characteristics and multiple measures of overall injury severity. Nephrectomy may impact overall survival and must be avoided when possible.