Step 2 Identification of the Renal Hilum

Once the descending colon, pancreas, and spleen have been mobilized and reflected medially en bloc, the surgeon should not have the need for retraction and should be able to identify the renal hilum with both instruments.

FIGURE 6 ■ The colonic mesentery is mobilized off of the anterior surface of Gerota's fascia en bloc with the pancreas and spleen. The splenophrenic ligament is divided to allow complete mobilization of the spleen away from the upper pole of the left kidney.

FIGURE 7 ■ The adrenal (AV) and gonadal veins (GV) are divided to attain maximum length on the renal vein (RV).

Once the descending colon, pancreas, and spleen have been mobilized and reflected medially en bloc, the surgeon should not have the need for retraction and should be able to identify the renal hilum with both instruments.

Clips on the specimen side should not be placed too close to the renal vein in anticipation of using the vascular stapling device later in the procedure. Retained clips may become entrapped within the Endo-GIA® stapler and cause misfiring of the device at the time of transection of the renal vessels.

If the renal vein is not easily identified, the left gonadal vein is an important structure because it reliably leads the surgeon to the renal vein.

Great care must be taken not to pastpoint the clips on the lumbar vein, because they may inadvertently catch the renal artery, which classically is located behind the lumbar branch of the renal vein.

Excessive traction on the renal hilum must be avoided to prevent arterial vasospasm.

Bleeding occurring during laparoscopic donor nephrectomy is most commonly encountered during hilar dissection.

The renal vein can often be visualized through Gerota's fascia, especially if adequate intravenous hydration has been maintained. The investing tissues overlying the renal vein are grasped and divided. The anterior surface of the renal vein is meticulously skeletonized, primarily by blunt dissection with the suction-irrigation device. Sharp dissection should be used sparingly around the renal hilum to minimize the chance of iatrogenic injury to the main renal vessels. Dissection is taken medially to ensure adequate length of the vein for transplantation. The take-off of the adrenal and gonadal veins is identified, and each vessel is isolated using blunt dissection. The harmonic scalpel is an excellent device to control several small branches that are often seen coming off the gonadal vein. Both the adrenal vein and gonadal vein are divided between hemoclips (Fig. 7).

Clips on the specimen side should not be placed too close to the renal vein in anticipation of using the vascular stapling device later in the procedure. Retained clips may become entrapped within the Endo-GIA stapler and cause misfiring of the device at the time of transection of the renal vessels (21).

The second dose of intravenous mannitol (12.5 g) is given at this point of the operation.

If the renal vein is not easily identified, the left gonadal vein is an important structure because it reliably leads the surgeon to the renal vein.

The gonadal vein is most easily identified inferiorly; it can then be traced in a cephalad direction to the level of the renal hilum. Once the gonadal vein has been safely transected, the surgeon gently grasps the proximal cut end of the gonadal vein and rotates it medially, exposing the lumbar vein. Hemostatic clips are applied to the lumbar vein prior to transection.

Great care must be taken not to past-point the clips on the lumbar vein, because they may inadvertently catch the renal artery, which classically is located behind the lumbar branch of the renal vein.

The renal artery is usually easily identified once the lumbar vein is transected. The renal artery should be dissected down to its origin from the aorta to achieve maximum renal vascular length.

Excessive traction on the renal hilum must be avoided to prevent arterial vasospasm. To minimize vasospasm, topical papaverine (30mg/mL) may be applied to the renal artery periodically. The renal artery should be skeletonized toward the origin of its surrounding perivascular and lymphatic tissues. Further skeletonization of the artery toward the renal sinus is not necessary. Aggressive dissection may cause vasospasm and will risk injury to branches of the artery if it bifurcates proximally.

Bleeding occurring during laparoscopic donor nephrectomy is most commonly encountered during hilar dissection. Bleeding emanating from small venous branches can often be controlled with direct pressure, placement of Surgicel or Gelfoam, or by temporarily elevating the insufflation pressure. Minor arterial sources of bleeding usually require hemoclips.

Large venous or arterial injuries, including damage to the main renal artery or vein often require open conversion to obtain hemostasis and ensure the safety of the living donor and the health of the allograft.

Successful dissection of the ureter during laparoscopic donor nephrectomy centers upon performing a wide dissection to ensure preservation of the periureteral tissue and blood supply, as well as obtaining satisfactory ureteral length for transplantation.

There is no need to identify the ureter along its course; this minimizes the likelihood of compromising its blood supply during dissection.

During dissection of the upper pole of the kidney, upper pole renal vessels may be encountered and potentially injured. Despite potential identification of these vessels on preoperative computed tomography arteriography, meticulous dissection is necessary to prevent injury.

Large venous or arterial injuries, including damage to the main renal artery or vein often require open conversion to obtain hemostasis and ensure the safety of the living donor and the health of the allograft.

Surgeons with advanced laparoscopic skills may attempt to manage certain vascular injuries laparoscopically or with conversion to a hand-assisted approach. However, the importance of maintaining a low threshold for open conversion with this procedure cannot be overstated.

When the decision for open conversion is made, the surgeon should hold pressure with a laparoscopic instrument until the necessary equipment for open conversion is available. The surgeon quickly decides which incision (flank, subcostal, or midline) will give the best exposure to the renal hilum.

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