**6.2. Bench surgery**

**6.1. Pancreas extraction**

as possible.

Adequate donor selection is crucial in pancreas transplantation, as described in the previous section. The extraction technique is of well-documented importance for a successful outcome [19]. Whether it is advocated for an enteric or bladder drainage, it requires the extraction of the entire pancreas and a segment of the duodenum with its vascularization—perfused by the celiac trunk and superior mesenteric artery—and drained by the portal vein. As this vascularization is shared with the liver, surgical techniques have been developed to allow the simultaneous extraction of both organs. In specific cases of hemodynamic instability, rapid or block extraction must be performed in order to perfuse the preservation solution as quickly

The surgery begins with a xipho-pubic incision, with sternotomy and opening of the pericardium. The first step is to carry out a thorough examination of all the organs to identify any pathology that contraindicates the donation. It is important to have vascular control to allow rapid cannulation in case of instability, performing the dissection and individualization with ligatures of the aorta above the iliac bifurcation and the infrarenal cava, as well as the inferior mesenteric vein, in the case of portal vein being cannulated through it. The superior mesenteric artery is then dissected, located above and to the left of the confluence of the left renal

A first visual evaluation of the organ is performed, after the opening of the smaller sac, sectioning the gastrocolic ligament, to expose the entire anterior surface of the body and tail of the pancreas, together with palpation of the pancreatic head. The next phase comprises the dissection of the hepatic hilum to identify the possible anatomical variants of the hepatic artery. The most frequent are the right hepatic artery from the superior mesenteric artery and the left hepatic artery that derives from the stomatologic coronary artery. The common bile duct is dissected and sectioned at its most distal part. An incision is made in the gallbladder fundus and physiological serum injected into the fundus from the bile duct. The gastroduodenal artery and the hepatic artery are identified and dissected at the celiac trunk. In addition, the left gastric artery and the coronary vein are also identified, as well as all the lymphatic vessels in the upper border of the pancreas. The splenic artery is individualized and referenced with 6/0 prolene suture to prevent its retraction in the pancreas. A silk ligature must be passed through the abdominal aorta above the celiac trunk, following the blunt dissection of the esophageal hiatus. Finally, the dissection of the portal vein is carried out after identifying the stomachatric coronary vein. It is important to perform the Kocher maneuver in order to access the entire duodenum and the posterior aspect of the pancreatic head. The dissection of the pancreas must be done through the "no touch technique." For the release of the pancreatic inferior aspect, mobilization of the entire transverse colon to the splenic angle is required. Subsequently, all the ligaments that fix the spleen to the retroperitoneum are sectioned for its separation from the kidney and the left adrenal gland, as well as the fixation of the body and tail to the retroperitoneum. Likewise, the section of the short gastrosplenic vessels and the dissection of the duodenum below the pylorus and at the level of the fourth portion is completed, for its subsequent sectioning to these two

vein with the cava, and a vessel loop is passed around it.

270 Organ Donation and Transplantation - Current Status and Future Challenges

levels by means of a self-suture device.

During the bench surgery, the duodenum-pancreatic graft is prepared. This must remain in conditions of hypothermia at 4°C until its implantation.

After ligation of the splenic vessels, splenectomy is performed. If a fatty pancreas is found to be present, it should be removed carefully, making the necessary sutures to minimize the hemorrhage during reperfusion. It is advisable to invaginate the line of staples of the duodenal ends (with continuous 3/0 silk suture, although it is variable depending on the group), to ensure maximum suture tightness and avoid further fistulas.

In case of absence of celiac trunk (usual in simultaneous liver and pancreas extractions), it will be necessary to carry out reconstructions of the arterial vascularization of the pancreas that allow a good anastomosis with the iliac vessels of the recipient.

There are different techniques of vascular reconstruction of the pancreatic graft:

**1.** Anastomosis of the arteries of the pancreas with a segment of the iliac bifurcation of the donor. It is the most used modality in the USA and Europe.

**2.** Spleno-mesenteric termino-terminal anastomosis between the splenic artery and the distal end of the superior mesenteric artery of the graft. For some groups, it constitutes the technique of choice for its simplicity.

Systemic venous drainage is most widely used. Some groups advocate the use of portal venous drainage for the hypothetical benefit of maintaining a more physiological insulin level and thus avoiding the hyperinsulinemia attributed to the systemic drainage. However, technically, it is more complex and its potential metabolic advantages are still

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Pancreatic exocrine secretion can be drained to the urinary tract or to the intestinal tract.

the conversion to enteric drainage in 15–30% of cases [20].

The urinary drainage (duodenocistostomy) contributed extraordinarily to consolidate the pancreas transplant, since it allows to monitor the rejection by the determination of pancreatic enzymes in the urine. However, the high incidence of complications associated with it require

Therefore, today, enteric drainage is the technique of election. The most common method of enteric drainage is the one in which the anastomosis is performed between the duodenum of the graft and the jejunum of the recipient, with the pancreatic graft positioned intraperitoneally. The enteric anastomosis can be performed to the proximal jejunum or to the distal ileum, in a termino-terminal, termino-lateral, or a latero-lateral anastomosis. The use of direct anastomosis is currently more widely used than Roux-en-Y anastomosis. However, Boggi et al. [21] have shown excellent results with the use of a Roux-shaped "Y" latero-lateral duodenojejunostomy (DY), with the retroperitoneal position of the pancreatic graft, and portal venous drainage. Exocrine drainage techniques to the stomach have also been described [22]. Duodenoduodenostomy (DD) is an interesting option for the drainage of digestive secretions when the pancreas is placed behind the right colon and is oriented in the cranial direction [23]. For the placement of the graft in the retroperitoneal position, the right colon is released medially together with the Kocher maneuver, so that the native duodenum is widely exposed. After the correct mobilization of the duodenum of the recipient, the latero-lateral anastomosis (2.5–3 cm) is performed between the duodenum of the graft and the second and third duodenal portion of the recipient with a doble suture, one internal for the mucosa with resorbable material (Vicryl 3/0) and a seromuscular external one, with nonabsorbable suture (3/0 silk). After this, the right

colon is repositioned to its usual position so that the pancreas remains immobile [24].

surgical field is prepared for the kidney implant on the left side.

tive care begins at the pre-operative and intraoperative periods.

lenge for the entire medical and surgical team.

**6.4. Surgical complications**

After the end of the intestinal anastomosis, the peritoneal cavity is washed with povidoneiodine serum. Some groups perform the wash with antibiotic solution to minimize the risk of peripancreatic infection and mycotic aneurysms. The peritoneum is then closed and the

The absence of complications after pancreas transplantation depends largely on the detailed knowledge of both the donor and the recipient. Therefore, to minimize morbidity, postopera-

The first 24–48 h is the most crucial for the graft and the recipient due to (a) the surgical trauma to which the patient has been subjected, (b) the ischemia-reperfusion phenomena of the transplanted organ, and (c) immunosuppression. As expected, the combination of these three insults, especially in a diabetic patient with vascular complications, constitutes a chal-

controversial.

**3.** Spleno-mesenteric termino-lateral anastomosis between the splenic artery and the superior mesenteric artery of the graft.

Once the bech surgery is performed, graft is perfused with about 100 cc of preservation solution and is ready to be implanted in the recipient.

#### **6.3. Pancreas implantation**

The simultaneous kidney and pancreas transplantation is the most frequent transplant modality performed worldwide. The surgical technique used for the implantation of the renal graft does not differ from that used for kidney transplant alone. For pancreas transplantation, although the surgical technique is not standard among centers, there is unanimous agreement in implanting the complete organ, including the second portion of the duodenum.

Traditionally, the intraperitoneal position has been preferred by most groups. In the last decade, different authors have suggested the implant of the graft in a retroperitoneal location, advocating a more physiological position [20].

The pancreas shloud be implanted prior to the kidney, given its worse tolerance to cold ischemia. The best way to perform the transplant is with a supra-infraumbilical midline laparotomy, from a point midway between the xiphoid and the umbilicus up to 2–3 cm of the pubis. The complete pancreas with a small portion of the donor's duodenum, which contains the Vater's ampulla, is located laterally in the right iliac fossa of the recipient. The cranial or caudal position of the head of the pancreas depends on each group. Placing the pancreas on the left side increases the risk of graft thrombosis.

The intervention begins with the dissection of the ureter and the right iliac vessels. These should be dissected and mobilized widely to facilitate subsequent vascular anastomoses. Hemostasis must be carefully performed, and the major lymphatic vessels must be ligated. To facilitate the venous anastomosis of the portal, it is advisable to mobilize the distal vena cava and the right iliac vein.

Once the iliac vessels are dissected, the venous anastomosis is performed first, between the portal vein of the graft and the most proximal part of the right primitive iliac vein or on the cava before the iliac bifurcation. Before starting the anastomosis, the vena cava is perfused with heparin (1 mg in 100 cc). The termino-terminal venous anastomosis is performed with two continuous sutures of Prolene 5/0.

The arterial anastomosis is then carried out between the right primitive iliac artery of the recipient and the superior mesenteric artery or the segment of the iliac artery of the graft, depending on the bench surgery performed. From the beginning of the anastomosis, the graft should be kept refrigerated by compresses of crushed ice. Once the arterial anastomosis is completed, the vessels are sequentially declamped, first the vein and then the artery. Pancreas should recover a normal coloration immediately.

Systemic venous drainage is most widely used. Some groups advocate the use of portal venous drainage for the hypothetical benefit of maintaining a more physiological insulin level and thus avoiding the hyperinsulinemia attributed to the systemic drainage. However, technically, it is more complex and its potential metabolic advantages are still controversial.

Pancreatic exocrine secretion can be drained to the urinary tract or to the intestinal tract.

The urinary drainage (duodenocistostomy) contributed extraordinarily to consolidate the pancreas transplant, since it allows to monitor the rejection by the determination of pancreatic enzymes in the urine. However, the high incidence of complications associated with it require the conversion to enteric drainage in 15–30% of cases [20].

Therefore, today, enteric drainage is the technique of election. The most common method of enteric drainage is the one in which the anastomosis is performed between the duodenum of the graft and the jejunum of the recipient, with the pancreatic graft positioned intraperitoneally. The enteric anastomosis can be performed to the proximal jejunum or to the distal ileum, in a termino-terminal, termino-lateral, or a latero-lateral anastomosis. The use of direct anastomosis is currently more widely used than Roux-en-Y anastomosis. However, Boggi et al. [21] have shown excellent results with the use of a Roux-shaped "Y" latero-lateral duodenojejunostomy (DY), with the retroperitoneal position of the pancreatic graft, and portal venous drainage. Exocrine drainage techniques to the stomach have also been described [22]. Duodenoduodenostomy (DD) is an interesting option for the drainage of digestive secretions when the pancreas is placed behind the right colon and is oriented in the cranial direction [23]. For the placement of the graft in the retroperitoneal position, the right colon is released medially together with the Kocher maneuver, so that the native duodenum is widely exposed. After the correct mobilization of the duodenum of the recipient, the latero-lateral anastomosis (2.5–3 cm) is performed between the duodenum of the graft and the second and third duodenal portion of the recipient with a doble suture, one internal for the mucosa with resorbable material (Vicryl 3/0) and a seromuscular external one, with nonabsorbable suture (3/0 silk). After this, the right colon is repositioned to its usual position so that the pancreas remains immobile [24].

After the end of the intestinal anastomosis, the peritoneal cavity is washed with povidoneiodine serum. Some groups perform the wash with antibiotic solution to minimize the risk of peripancreatic infection and mycotic aneurysms. The peritoneum is then closed and the surgical field is prepared for the kidney implant on the left side.
