One quandary has been the management of suspected renal trauma in patients without pre‐operative CT imaging. Data suggests that even if patients are undergoing surgical exploration for associated non‐urologic injuries, renal exploration is not always necessary. The only absolute indication for renal exploration is a pulsatile or expanding retroperitoneal hematoma. Stable retroperitoneal hematomas should not be explored [24]. Obvious urinary leakage from a penetrating mechanism requires evaluation to exclude a renal pelvis or ureteral injury (see Figure 2.4). In one large series of patients undergoing exploratory laparotomy for renal GSWs, 56% of patients did not need renal exploration and renal exploration was associated with a 50% nephrectomy rate [35]. If patients undergo emergent laparotomy without imaging and a stable zone II (retroperitoneal flank) hematoma is not explored, they should receive appropriate renal imaging once stable, in order to evaluate the extent of the injury.
Figure 2.3 Twenty‐one‐year‐old male who sustained a GSW to the abdomen. He had a grade IV right PRI, with injuries to the liver and duodenum. (a) CT demonstrates a significant urine leak on initial delayed phase imaging. (b) He was taken to the operating room for retrograde pyelogram and ureteral stenting. Pyelogram demonstrates contrast extravasation from the middle calyx. Arrow depicts area of contrast extravasation. (c) Repeat CT scan with delayed phase imaging at two weeks demonstrates improved, but persistent contrast extravasation. He was taken to the operating room six weeks after ureteral stenting where retrograde pyelogram demonstrated complete healing of his collecting system and his stent was removed.
Source: courtesy of Jonathan Wingate, MD.
Operative
Operative management of PRI is not as nuanced as NOM – an unstable patient, unresponsive to resuscitation, requires immediate surgical exploration. Surgical exploration is traditionally performed via a midline transabdominal approach. These cases are often performed in conjunction with trauma surgeons, as the rates of concomitant non‐GU organ injuries are very high [8, 36].
Prior to exploring a zone II hematoma, the surgeon should ensure there is a contralateral kidney if no pre‐operative imaging was obtained. This can be performed by manual palpation of the contralateral kidney or a single shot urogram (2 ml/kg of IV contrast followed by a KUB at 10 minutes).
Figure 2.4 Twenty‐five‐year‐old female who sustained multiple stab wounds with a machete. (a) CT scan demonstrates contrast extravasation from the left collecting system. Intra‐operatively, she was noted to have a 1.5 cm renal laceration in the inferior pole. There was active urine extravasation from the wound. A renorrhaphy was performed. She also had injuries to the small bowel and right chest. (b) CT performed 48 hours after renorrhaphy demonstrates resolution of the urine leak.
Source: courtesy of Jonathan Wingate, MD.
Principles of damage control surgery are abbreviated operation, intensive care resuscitation, and definitive surgery. For penetrating trauma, if there is concern for active bleeding at time of laparotomy, source control should be obtained. If there is an expanding zone II hematoma consistent with active renal bleeding, this should be explored. However, for non‐expanding hematomas, if the patient is unstable, four‐quadrant packing with temporary abdominal closure may be performed in order to allow for resuscitation.
There are two surgical approaches to the kidney – medial or lateral. In the medial approach, the renal vessels are isolated prior to renal exploration as early vascular control may decrease nephrectomy rates and blood loss during surgery [37]. The retroperitoneum is incised over the aorta superior to the inferior mesenteric artery and medial to the inferior mesenteric vein. The anterior surface of the aorta is explored until the left renal vein is encountered crossing anteriorly over the aorta. Vessel loops are then placed around the renal hilum and early vascular control is obtained. The kidney is then exposed by incising the peritoneum lateral to the colon and mobilizing the peritoneum off Gerota's fascia. This approach takes longer and may be difficult in the setting of large hematomas.
In cases of active hemorrhage or an unstable patient, one may not have time to get proximal renal vascular access. For rapid exposure, the kidney can be approached laterally – the retroperitoneum lateral to the kidney is opened and the kidney is delivered into the operative field. Manual compression of the renal parenchyma can help tamponade the bleeding. The hilum can also be manually compressed then a vascular clamp is applied. For significant bleeding, more proximal control can be temporarily obtained through digital compression of the aorta at the diaphragmatic hiatus or with the use of a padded Richardson retractor [38].
Figure 2.5 Renorrhaphy. (a) Deep midrenal laceration into pelvis. Basic reconstructive principles of renorrhaphy include (b) closure of pelvis and ligation of vessels, (c) defect closure, and (d) placement of Gelfoam® bolsters.
Source: from Buckley and McAninch [48], with permission.
Regardless of approach, after vascular control, the renal fascia is opened and the kidney is dissected from the surrounding hematoma. Renal reconstruction is then performed. The principles include complete renal exposure, debridement of nonviable parenchyma, suture ligation of bleeding vessels, closure of any collecting system injuries, and re‐approximation of the parenchyma (see Figure 2,5). For injuries to the renal pelvis, a ureteral stent should be placed. This can be placed antegrade via the collecting system defect. Then the renal pelvis should be repaired with a fine, absorbable suture (i.e. 5–0 PDS: polydioxanone suture). Collecting system defects with overlying renal parenchyma, even large ones, do not require routine stenting. Omental flaps may be used for coverage of the repair.
All sutures during the renorrhaphy should be absorbable. The renorrhaphy is performed using an absorbable suture (i.e. 2–0 polysorb) in interrupted horizontal mattress fashion. Pledgets made out of Surgicel can be used to prevent tearing of the sutures from the renal parenchyma. Some urologists place a bolster dressing in the renorrhaphy bed with a hemostatic agent such as Gelfoam or Surgicel (see Figure 2.6). A closed suction drain should be placed in the retroperitoneum but not directly on the renorrhaphy site.
Thrombosis