Indications for nonoperative management of renal stab wounds

Purpose: During the last 20 years 2,732 patients have presented to San Francisco General Hospital with renal trauma. Of these patients 198 sustained unilateral and 1 had bilateral stab wounds for a total of 200 renal injuries. We evaluated this subgroup of penetrating renal trauma cases to characterize the nature of the injuries and establish treatment guidelines for successful management. Materials and Methods: Preoperative staging was performed in 143 cases (71.5%) with excretory urography or computerized tomography. Based on radiographic and clinical findings the injuries were graded according to the organ injury scaling system. There were 75 grade I (37.5%), 33 grade II (16.5%), 52 grade III (26%), 38 grade IV (19%) and 2 grade V (1%) injuries. Associated organ injuries in 122 patients (61%) involved primarily the liver, pleura, diaphragm and spleen. Mean injury severity score was 20.6 (range 4 to 50). Results: Nonoperative treatment was selected in 108 patients (54%). In 3 patients initially treated nonoperatively delayed bleeding required surgical intervention. Of the 92 renal units explored 74 were reconstructed (80.4%) and 11 required nephrectomy (12%). The overall renal salvage rate was 94.5%. Complications included infection in 2 and hematoma in 2 patients each. Four patients died of nonurological complications. Followup imaging studies were obtained in 26 reconstructed kidneys (35.1%). None of the 107 patients who were followed demonstrated delayed sequelae of renal injuries or new onset of hypertension. Conclusions: Stab wounds are the most common penetrating trauma to the kidney. More than half of these injuries can be selectively treated nonoperatively. Management criteria are based on aggressive radiographic, laboratory, clinical and when indicated surgical staging. Meticulous attention to reconstructive techniques in renal exploration can ensure an excellent renal salvage rate.