The frequency and indication for renal exploration and repair have dramatically decreased with the ease and accuracy of computed tomography (CT) renal staging. Complex kidney fractures, deep lacerations, and types of penetrating trauma can now be safely and successfully managed in a nonoperative manner. The main indication for renal exploration remains hemodynamic instability. Critically ill patients with severe hemodynamic instability undergo immediate operative exploration to control intraabdominal bleeding and may require a damage control nephrectomy to evade immediate mortality. In a non–life-threatening situation, renal exploration and reconstruction allow for renal salvage and reduce the risk of late complications and a prolonged recovery phase.
Severe renal injuries may present in polytrauma settings with multiple associated injuries or with more isolated abdominal or flank pain, ecchymosis, or tenderness. They can be seen with rib or spinous process fractures. Hematuria can be gross, microscopic, or absent and does not necessarily correlate with the degree of injury. Serial hematocrits are obtained.
Stable patients undergo CT radiographic staging of renal injuries. The degree of renal injury along with hemodynamic stability, mechanism of injury, and presence of nonurologic intraabdominal injuries determines selective management. Grade I to III injuries are managed nonoperatively with excellent renal preservation and minimal risk of future morbidity. Careful assessment and decision making are critical in severe renal injuries (grades IV to V). Although nonoperative management is viable and successful in appropriately staged renal injuries, other times operative explorations and renorrhaphy are preferred. Renal exploration and repair can prevent prolonged recovery periods with extensive imaging and delayed complications that can be seen with nonoperative management. CT findings of a medial hematoma or laceration or rapidly expanding perirenal hematoma with vascular contrast extravasation are concerning and are the most likely to require intervention. When a segmental renal vascular injury is identified and causing continued hemorrhage, angiographic embolization can be used to avoid open exploration.
Surgical Approach to Renal Exploration
A midline transabdominal incision from the xiphoid to the pubic symphysis ( Fig. 17.1 ) provides optimal exposure for complete abdominal exploration, detection of associated intraabdominal injuries, and access to the great vessels in anticipation of renal exploration. Immediate bleeding should be controlled with laparotomy packs and surgical repair.
Exposure, Important Landmarks, and Renal Hilar Control
The transverse colon is placed onto the chest over a moist laparotomy pack. The small bowel is extricated to the patient’s right side and retracted superiorly to allow access to the retroperitoneum, inferior vena cava, and aorta for isolation of the injured renal unit hilar vessels ( Fig. 17.2 ). The inferior mesenteric artery (IMA) is identified and an incision made superior to it directly down to the aorta. The dissection is carried cephalad to the left renal vein, which reliably (~95%) crosses anterior to the aorta. When retroperitoneal anatomy is difficult to identify secondary to a large hematoma ( Fig. 17.3 ), the inferior mesenteric vein (IMV) can be identified and used as a landmark to identify the aorta. An incision is made medial to the IMV and extended up to the ligament of Treitz on the anterior surface of the aorta to identify the anteriorly crossing left renal vein.
Renal Hilum Vessel Isolation
The left renal vein is always the first structure identified even for a right renal injury. Both the right and left renal artery are located posterior and slightly superior to the left renal vein. The right renal artery can be identified in the intraaortocaval space by elevating the left renal vein and dissecting on the medial aspect of the aorta ( Fig. 17.4, A ). The right renal vein can be found on the lateral aspect of the vena cava at about the same level as the left renal vein. Vessel loops are placed around the artery and vein of the injured kidney in anticipation of opening the retroperitoneal hematoma ( Fig. 17.4, B ). Mobilization of the second portion of the duodenum is often necessary to visualize the right renal vein and should be performed if a right renal hilar injury is suspected.
Entering the Retroperitoneal Hematoma and Renal Exposure
The colon is mobilized medially by incising the white line of Toldt lateral to the colon. Gerota fascia is opened sharply and the hematoma around the kidney is evacuated ( Fig. 17.5 ). Unless severe bleeding is encountered that cannot be controlled with manual compression, the vessels are not clamped, thus avoiding warm ischemia. The kidney is completely mobilized and inspected to determine the full extent of the injury, to identify the entrance and exit wound of a penetrating injury, and to avoid a missed injury.