High Grade Blunt Renal Trauma: Predictors of Surgery and Long-Term Outcomes of Conservative Management. A Prospective Single Center Study

Abstract

The management of major renal trauma has shifted in the last decade in favor of a nonoperative approach. Our level 1 trauma center promotes this approach with the objective of renal function preservation. However, certain situations still require surgery. In this study we analyze predictors of surgery and long-term outcomes after conservative management. From January 2004 to March 2015 we prospectively collected data from all patients admitted to our institution for high grade blunt renal trauma (grades IV and V). Nonoperative management was considered successful when patients did not undergo surgical exploration, regardless of angioembolization or endoscopic treatment. Of 306 patients with renal trauma 151 presented with major injuries, including 124 grade IV and 27 grade V. Nonoperative management was successful in 110 (89%) cases of grade IV and 14 (52%) cases of grade V lesions. Deceleration mechanism (p=0.03), associated lesions (p=0.001), percentage of devitalized parenchyma (p=0.012), angioembolization (p <0.001), hemodynamic instability (p <0.001) and low hemoglobin (p=0.001) were more frequent in patients treated surgically. On multivariate analysis grade (OR 7.36, p=0.01) and hemodynamic instability (OR 4.18, p=0.04) were the only independent predictors of surgical treatment. Long-term followup of preserved kidneys revealed a remaining 40% and 0% relative renal function after grade IV and V injuries, respectively. Only devascularized parenchyma greater than 25% predicted the decline of long-term renal function. Nonoperative management can and should be performed safely in cases of grade IV injuries whenever possible, with valuable long-term renal function. It can also be initiated in grade V cases. However, surgeons should consider nephrectomy with the onset of any suspicious symptoms.