Contemporary management and outcomes of penetrating traumatic AAST–OIS grade III and IV kidney injuries undergoing laparotomy: a Trauma Quality Improvement Program analysis

This study aimed to compare the outcomes of renal salvage (no nephrectomy) to nephrectomy patients with a penetrating American Association for the Surgery of Trauma-Organ Injury Scale grade III or IV kidney injury. The 2013-2021 Trauma Quality Improvement Program dataset was queried for patients with a penetrating grade III or IV kidney injury who underwent laparotomy within 24 h of admission. The association between nephrectomy and binary outcomes was investigated using Poisson regression models, with results presented as a prevalence ratio (PR) and corresponding 95% confidence interval (CI). A total of 2,214 grade III and 2,669 grade IV kidney injuries were identified. 89% of grade III injuries and 54% of grade IV injuries were managed without nephrectomy. After adjustment for confounding, nephrectomy in patients with a grade III penetrating kidney injury was associated with an increased risk of mortality [adjusted PR (95% CI): 1.53 (1.06-2.20), p = 0.023], complications [adjusted PR (95% CI): 1.25 (1.05-1.48), p = 0.010], post-complication mortality [adjusted PR (95% CI): 1.80 (1.09-2.96), p = 0.022], and ICU admission [adjusted PR (95% CI): 1.05 (1.00-1.11), p = 0.046], compared to renal salvage. In patients with a grade IV penetrating kidney injury, nephrectomy was only associated with an increased risk of ICU admission [adjusted PR (95% CI): 1.06 (1.02-1.09), p = 0.001], compared to renal salvage. Consequently, in patients with a grade III penetrating kidney injury, nephrectomy was associated with an increased risk of adverse outcomes. Among patients with a grade IV injury, nephrectomy was associated only with an increased risk of ICU admission. However, given the potential for residual confounding, these findings should be interpreted with caution.