Kidney Procurement

The main principle of donor kidney procurement is en bloc removal of both kidneys with an intact segment of aorta and inferior vena cava.10-12 This allows safe and rapid excision of kidneys with maximal vessel length available for anastomosis. Operative trauma to renal vessels and vascular supply of the ureter is kept minimal with this technique. Organ donors can be expected to have a renal vascular or ureteric anomaly in up to 49% of cases (Table 8.2).13

Kidney Procurement as a Part of Multiple Organ Recovery If the kidneys are to be procured as a part of multiple organ recovery, they are removed after hepatectomy and/or pancreatectomy. The technique described previously for liver procurement is compatible for simultaneous kidney removal. Cold perfusion of the liver for in situ cooling also allows cooling of the pancreas and kidneys. All of the dissection is made in a cold and bloodless field.

Table 8.2. Renal vascular and ureteric anomalies. Findings in a series of400 cadaver kidney donors.13

Right (%)

Left (%)

Renal artery

Double

25

22

Triple

4

3

Renal vein

Double

13

2

Triple

1

< 1

Double ureter

1

1

First, ureters are identified in the pelvis. They are dissected free and divided distally close to the urinary bladder. Periuretral fatty areolar tissue containing the vascular supply to the ureter should be preserved as much as possible to avoid devascularization. Both ureters are freed to the level of the lower kidney pole. Hemostats are applied to the periureteral fat at the distal ends of the ureters for traction. Next kidneys are dissected out. They are dissected beyond the plane of Gerota's fascia. The right kidney usually has already been exposed as the right colon and duodenum are mobilized as a part of liver procurement. For the exposure of the left kidney, the line of Toldt is incised and the left colon is retracted medially. Splenic and diaphragmatic attachments are divided. Then the left meso-colon is divided for complete dissection of the left kidney. While retracting anteriorly both kidneys are mobilized in the superior and lateral aspects staying away from the capsule. Hilar dissection is avoided.

The inferior vena cava is transected just above the bifurcation. The aorta is divided distal to the cannula and the cannula is kept in place for traction. Kidneys, ureters, aorta and vena cava are lifted upward and are not allowed to fall posteriorly. All tissue lying posteriorly is cut, staying on the prevertebral fascia until the previously transected suprarenal aorta and inferior vena cava are reached. After completing the posterior dissection, the residual attachments between the kidneys and gastrointestinal tract are divided. With this technique kidneys are removed en bloc.

The kidneys are taken to the back table and placed in a basin of ice saline. If the organs appear to have been uniformly flushed, no additional back table flush is needed. The block is placed in the anatomic position and properly oriented. The left renal vein passing anterior to the aorta is divided with a cuff of vena cava. The entire vena cava stays with the right kidney. This technique allows the recipient surgeon to increase the length of the right renal vein with the cuff of vena cava in case of a short renal vein. Next the block is turned posteriorly. The aorta is opened in the midline between the lumbar arteries in the posterior aspect. The renal arteries are identified from the inside and the anterior wall of the aorta is then divided. With the internal view, the risk of injury to renal arteries is minimized. Frequent vascular anomalies (venous and arterial) to the kidneys require the meticulous attention of an experienced surgeon.

Obvious perinephric fat can be removed but the rest of the dissection is left for the recipient surgeon. The kidneys are separately packaged in plastic bags with UW solution. Then plastic bags are placed in a cooler and kept in ice for transportation.

Kidney Procurement Alone

If only kidneys are to be removed we still make an incision from the sternal notch to the symphysis pubis. Wide exposure reduces the risk of operative injury to kidneys and their vascular supply. After placement of sternal and abdominal retractors the peritoneum in the right paracolic gutter is incised. The right colon is mobilized and retracted superiorly and medially. The small bowel mesentery is incised and swept up. The duodenum is Kocherized and retracted upward with the pancreas. After this preliminary dissection, the right kidney, aorta, vena cava and superior mesenteric artery are exposed. The inferior mesenteric artery is ligated and divided. The distal aorta is dissected free and encircled with two umbilical tapes. With the retraction of intestines upward, the superior mesenteric artery is identified above the left renal vein. It is encircled with heavy ligature to be tied off later. The supraceliac aorta is isolated and encircled with an umbilical tape. At this point, although it is not necessary, the celiac axis can be ligated or clamped.

After systemic heparinization with 20,000 U, the distal aorta is cannulated and the supraceliac aorta is cross-clamped. The vena cava is vented by incising it in the pericardium. The aorta is infused with 2 liters of UW solution. Previously encircled superior mesenteric artery is ligated. The abdominal cavity is filled with slushed-ice saline for topical cooling. The rest of the dissection is carried out in a bloodless field as described previously.

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