Management of renal injury

GU: genitourinary; HD: hemodynamically; CT: computed tomography.
* Renal trauma can cause injury to the parenchyma or renal vessels, causing bleeding, or injury to the collecting system, leading to urine extravasation. Initial trauma management includes placement of a urethral catheter.
¶ Suspicion for injury is increased with direct blow to the back/flank, flank ecchymosis, displaced rib fracture, penetrating injury in proximity to kidney or ureters, and hematuria. Rapid deceleration injury can cause avulsion of the ureter at the ureteropelvic junction, avulsion of the renal vessels or arterial dissection/thrombosis.
Δ Bleeding from renal injury is due to parenchymal or renal vessel injury; collecting system injuries do not cause appreciable bleeding.
◊ CT scanning with three phases (noncontrast phase, corticomedullary phase, excretory phase) is needed to diagnose renal injuries.
§ For patients with concomitant abdominal injuries requiring laparotomy, explore and repair penetrating injuries as indicated.
¥ Renal artery thrombosis is often an unexpected finding on CT scan in a hemodynamically stable patient and can be observed. If renal artery occlusion is bilateral or renal artery occlusion occurs in a solitary kidney, surgical revascularization for attempted renal salvage is recommended.
‡ If there is a high suspicion for collecting system injury, exploration and repair is undertaken. For urinoma in a severely injured patient with multiple injuries or urinoma diagnosed in delayed fashion, a perinephric drain may be appropriate.
† Management may include closure of lacerations, wrapping the kidney for hemostasis, or partial nephrectomy. Nephrectomy is avoided whenever possible but may be necessary (eg, devascularization, failed attempt to control bleeding). Palpate the contralateral renal pedicle to ensure a strong renal artery pulse before performing nephrectomy.
** Renal artery injuries often present with hemodynamic instability. Surgical repair of arterial injury has poor results. Repair of isolated renal vein injuries should be attempted.
¶¶ Predictors of need for angioembolization include medially located hematoma (toward aorta or inferior vena cava), peripheral rim distance of >25 mm, and transfusion >2 U red blood cells. Intravenous contrast extravasation alone is not a sensitive indicator.
ΔΔ Follow algorithm as for HD stable patient. Conservative management of nonexpanding renal hematoma identified intraoperatively is the same as for injury identified on imaging studies in hemodynamically stable patients.