Читать книгу A Clinical Guide to Urologic Emergencies - Группа авторов - Страница 43

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 of the renal artery and vein should be managed conservatively. Although surgical revascularization has a high technical success rate, most patients have irreversible ischemic damage or delayed thrombosis [39, 40]. These repairs should only be attempted on patients with solitary kidneys or if they have bilateral occlusion.

Figure 2.6 Forty‐four‐year‐old male who sustained a GSW with a grade III left renal laceration. While undergoing exploratory laparotomy for multiple abdominal organ injuries, the urology service was consulted for management of his renal injury. (a) Pre‐operative CT scan demonstrated a left grade III renal injury without collecting system injury (delayed imaging not shown). (b) Intra‐operative photo showing the anterior‐medial renal laceration. (c) This was repaired by renorrhaphy. Final appearance shows interrupted 4‐0Vicryl sutures over a Gelfoam^® bolster.

Source: photo courtesy of Alexander Skokan, MD, University of Washington.

Indications for nephrectomy include an unreconstructable kidney, significant vascular injury, or an unstable patient who cannot tolerate an attempted repair. In the civilian trauma literature, the nephrectomy rate for PRI ranges from 19 to 31% [8, 41, 42].

For the recent military conflicts in the Middle East, renal trauma comprised 29.6% of the GU injuries, with a 65.5% nephrectomy rate [13, 43]. These rates are much higher than civilian penetrating trauma and seem dissonant with the protective effects of body armor. These high nephrectomy rates are driven by two variables unique to expeditionary medicine: (i) high kinetic energy weapons, such as assault rifles and improvised explosive devices which rendered the majority of the kidneys unreconstructable; and (ii) the unique logistical limitations of battlefield to intercontinental evacuation. The combat damage control paradigm involves up to 10 stages to allow for battlefield evacuation, multiple surgeries and resuscitations, and intercontinental transport, which may contribute to higher nephrectomy rates independent of the mechanistic differences of the PRI [44]. Furthermore, expeditionary surgical teams do not have the same access to resources such as blood products and intensivists. These factors contribute to more aggressive measures to gain definitive hemodynamic stability, even in light of damage control principles.