Fig. 6.1
A pancreas suitable for transplantation
Fig. 6.2
A pancreas not suitable for transplantation
2.
Splenectomy should be performed by dividing the splenic artery (red arrow) and vein close to the splenic hilum (Figs. 6.3 and 6.4). The pancreatic parenchyma can sometimes extend far into the splenic hilum (broken blue line) (Fig. 6.4), and care should be taken not to injure the tail of the pancreas. In the event of known splenic trauma, detailed and careful inspection of the tail of the pancreas should be undertaken to ensure that no injury exists.
Fig. 6.3
Splenectomy should be performed by dividing the splenic artery and vein close to the splenic hilum
Fig. 6.4
Splenectomy should be performed by dividing the splenic artery (red arrow) and vein close to the splenic hilum. The pancreatic parenchyma can sometimes extend far into the splenic hilum (broken blue line)
3.
Excess tissue along the superior and inferior aspect of the body of the pancreas is then ligated. Along the superior border of the pancreas, care should be taken not to injure the splenic artery (Fig. 6.5). The orifice of the splenic artery is visualized at the medial aspect of the upper border of the body, and tagged with a stitch for easy identification. At the inferior border of the body, the medial aspect is marked by the inferior mesenteric vein (blue arrow), which should be ligated (Fig. 6.6).
Fig. 6.5
Excess tissue along the superior and inferior aspect (grey arrows) of the body of the pancreas is ligated, taking care not to injure the splenic artery along the superior border of the pancreas
Fig. 6.6
Excess tissue along the superior and inferior aspect (black arrows) of the pancreas body has beed ligated. At the inferior border of the body, the medial aspect is marked by the inferior mesenteric vein (blue arrow), which should be ligated
4.
The head of the pancreas is then approached from its posterior aspect. The common bile duct (green arrow) is identified and suture ligated. The portal vein (blue arrow) is identified and dissected free for a short distance to allow for easier anastomosis in the recipient (Fig. 6.7).
Fig. 6.7
The head of the pancreas is then approached from its posterior aspect. The common bile duct (CBD, green arrow) is identified and suture ligated. The portal vein (blue arrow) is identified and dissected free for a short distance
5.
Similarly, the superior mesenteric artery (SMA) is mobilized by dissecting and ligating the surrounding ganglion tissue (Fig. 6.8). Care should be taken not to carry the dissection too close to the pancreatic parenchyma, for fear of injuring the inferior pancreaticoduodenal artery. Similarly, excess tissue around the origin of the splenic artery is ligated (Fig. 6.9).
Fig. 6.8
The superior mesenteric artery (SMA) (yellow arrow) is mobilized by dissecting and ligating the surrounding ganglion tissue
Fig. 6.9
Excess tissue around the origin of the splenic artery (red arrow) is ligated
6.
The pancreas is then approached from its anterior aspect. Lymphatic and ganglion tissue along the superior aspect of the head are ligated. The proximal duodenal cuff staple line (which should be distal to the pylorus) is inverted with a running nonabsorbable suture (Fig. 6.10). Similarly, the long duodenal-jejunal segment distally is dissected off the pancreas. If a bladder-drained graft is planned, the duodenal cuff should be kept short to minimize metabolic losses. The excess bowel can then be divided and discarded using a stapling device; the staple line is oversewn (Fig. 6.11). Alternatively, if the exocrine drainage anastomosis is to be done using a stapling device, the segment can be left long to allow for introduction of the stapler.
Fig. 6.10
The proximal duodenal cuff staple line (which should be distal to the pylorus) is inverted with a running nonabsorbable suture. Similarly, the long duodenal-jejunal segment distally is dissected off the pancreas. SMA superior mesenteric artery, SMV superior mesenteric vein
Fig. 6.11
If a bladder-drained graft is planned, the duodenal cuff should be kept short to minimize metabolic losses. The excess bowel can be divided and discarded using a stapling device (broken blue line); the staple line is oversewn
7.
Again, looking at the pancreas from its anterior aspect, redundant tissue in the area of the root of the transverse mesocolon is ligated. Finally the root of the mesentery, which contains the SMA and SMV, is either serially ligated or taken with a vascular stapler (Fig. 6.12). The staple line is then oversewn with a monofilament permanent suture.
Fig. 6.12
Redundant tissue in the area of the root of the transverse mesocolon is ligated. Finally the root of the mesentery, which contains the SMA and SMV (broken line and arrows), is either serially ligated or taken with a vascular stapler
8.
Preparations are now made to place the arterial Y-graft onto the two arterial vessels to create one arterial orifice for anastomosis in the recipient. The distance between the superior mesenteric and splenic arteries is noted, and the donor iliac artery “Y-graft” is trimmed to appropriate length (Figs. 6.13 and 6.14).
Fig. 6.13
Preparing to place the arterial Y-graft onto the two arterial vessels to create one arterial orifice for anastomosis in the recipient, the donor iliac artery “Y-graft” is trimmed to appropriate length (broken blue line)
Fig. 6.14
The distance between the superior mesenteric and splenic arteries is noted
9.
An end-to-end anastomosis is fashioned between the internal iliac artery stump of the Y-graft and the splenic artery of the pancreas graft (Fig. 6.15). The external iliac artery limb of the Y-graft should then be cut to appropriate length so that it lies next to the SMA without any redundancy.
Fig. 6.15
An end-to-end anastomosis is fashioned between the internal iliac artery stump of the Y-graft and the splenic artery of the pancreas graft. The external iliac artery limb of the Y-graft should be cut to appropriate length so that it lies next to the SMA without any redundancy
10.
The end of the external iliac artery of the Y-graft is then anastomosed to the SMA, again in an end-to-end fashion (Fig. 6.16).
Fig. 6.16
The end of the external iliac artery of the Y-graft is then anastomosed to the SMA in an end-to-end fashion
11.
The pancreas graft is now ready for implantation (Fig. 6.17).
Fig. 6.17
The pancreas graft is now ready for implantation
6.3 Simultaneous Pancreas Kidney (SPK): Systemic/Enteric Drainage
Pancreas transplantation is most commonly performed in conjunction with simultaneous kidney transplantation (Fig. 6.18). The pancreas is most often drained into the systemic circulation, usually by connecting the portal vein of the pancreas graft to the iliac vein of the recipient. This drains the endocrine secretions into the systemic circulation. The exocrine secretions can then be managed by connecting the donor duodenum to the small bowel. Alternatively, the portal vein of the graft can be drained into the portal circulation, by connecting to the superior mesenteric vein or a large tributary of the vein. Exocrine secretions are then drained into the recipient’s bowel, as the pancreas will generally not reach the bladder when drained into the portal circulation.
Fig. 6.18
In simultaneous pancreas-kidney transplantation, the pancreas is most often drained into the systemic circulation, usually by connecting the portal vein of the pancreas graft to the iliac vein of the recipient. This drains the endocrine secretions into the systemic circulation. The exocrine secretions can then be managed by connecting the donor duodenum to the small intestine
6.3.1 Operative Procedure
1.
The initial part of the operation usually involves implantation of the kidney. If there is concern regarding prolonged ischemia of the pancreas graft, then the pancreas should be implanted first, followed by the kidney. In either case, a long midline incision is performed first. The sigmoid colon is mobilized by division of the white line of Toldt. The common iliac artery and vein are identified and circumferentially dissected free of surrounding tissue. The renal graft is then anastomosed to the iliac vein and artery with permanent monofilament suture (Figs. 6.19 and 6.20).
Fig. 6.19
The renal graft is anastomosed to the iliac vein and artery
Fig. 6.20
The renal graft is anastomosed to the iliac vein and artery with permanent monofilament suture
2.
The sigmoid colon is returned to its position where it drapes over and covers the kidney (broken blue lines) (Fig. 6.21).
Fig. 6.21
The sigmoid colon is returned to its position (blue arrows) where it drapes over and covers the kidney (broken blue lines)
3.
The retractors are then repositioned in preparation for the dissection of the right-sided iliac vessels. The cecum and right colon are mobilized to the left to expose the right iliac vessels and to make space for the pancreas graft (Fig. 6.22).
Fig. 6.22
The retractors are then repositioned in preparation for the dissection of the right-sided iliac vessels. The cecum and right colon are mobilized to the left to expose the right iliac vessels and to make space for the pancreas graft
4.
A good length of the common iliac, external iliac, and internal iliac arteries are dissected out in preparation for the arterial anastomosis (Fig. 6.23). The distal common iliac artery is the preferred site for implantation of the artery (blue mark).
Fig. 6.23
A good length of the common iliac, external iliac, and internal iliac arteries are dissected out in preparation for the arterial anastomosis. The distal common iliac artery is the preferred site for implantation of the artery (blue mark)
5.
The right iliac vein is then completely mobilized by division of the pelvic branches (Fig. 6.24). It is necessary to divide the pelvic branches (yellow arrow, Fig. 6.25) of the iliac vein (blue dashed line) to allow the vein to be in a more superficial location. Dividing the branches also allows the vein to be lateral to the artery, which is the correct orientation when the pancreas is oriented such that the duodenum is pointing towards the recipient’s pelvis. It is wise to suture ligate the stumps of these branches from the main right iliac vein to prevent ligature slippage and bleeding.
Fig. 6.24
The right iliac vein is then completely mobilized and all the pelvic branches of this vein should be divided (broken line) to allow the vein to be in a more superficial location. Dividing the branches also allows the vein to be lateral to the artery
Fig. 6.25
The right iliac vein is completely mobilized (broken blue line). The pelvic branches (yellow arrow) of this vein should be divided. It is wise to suture ligate the stumps of these branches from the main right iliac vein to prevent ligature slippage and bleeding
6.
Clamps are placed on the iliac artery and vein, proximally and distally, and the sites for the venous and arterial anastomoses are determined. Arteriotomy and venotomy are made and stay sutures are placed (Fig. 6.26).
Fig. 6.26
Clamps are placed on the iliac artery and vein, proximally and distally, and the sites for the venous and arterial anastomoses are determined. Arteriotomy and venotomy are made and stay sutures are placed
7.
The venous anastomosis is performed first, creating an end-to-side anastomosis. Care should be taken to ensure that the vein is not twisted or left too long (Fig. 6.27).
Fig. 6.27
The venous anastomosis is performed first, creating an end-to-side anastomosis. Care should be taken to ensure that the vein is not twisted or left too long
8.
The arterial Y-graft is then trimmed to appropriate length and anastomosed to the common iliac artery (Fig. 6.28). Figure 6.29 shows the completed vascular anastomoses.
Fig. 6.28
The arterial Y-graft is trimmed to appropriate length and anastomosed to the common iliac artery
Fig. 6.29
The completed vascular anastomoses, showing the Y-graft (yellow arrow) anastomosed to the iliac artery
9.
The clamps are removed and the pancreas allowed to reperfuse (Fig. 6.30). The graft should be inspected carefully at this point to control any bleeding.
Fig. 6.30
The clamps are removed and the pancreas allowed to reperfuse
10.
The exocrine secretions can then be drained by connecting the donor duodenum to the small bowel of the recipient. The graft duodenum–to–small bowel anastomosis is generally preferred because of a lower incidence of metabolic and urinary tract problems, but if there is any concern regarding the donor duodenum, or if ischemia time has been long, a bladder anastomosis is always safer. The bowel anastomosis can be performed either to a Roux-en-Y limb, or just simply to the side of the bowel. The site should be fairly proximal to prevent future diarrhea, but it is more important to choose a portion of the bowel that reaches the donor duodenum without tension. The bowel anastomosis can be performed in a hand-sewn fashion or with a stapler. With a hand-sewn technique, a two-layer anastomosis is done, using a nonabsorbable suture for the outer layer and an absorbable suture for the inner layer. Both layers can be performed with a simple running suture technique. The outer layer of the back wall is placed first after carefully aligning the donor duodenum (blue arrow) and recipient small bowel (yellow arrow) (Fig. 6.31). Careful alignment is important to ensure that no twisting or internal hernia is created. The correct orientation is with the more distal portion of the recipient bowel aligning with the more distal portion of the donor duodenum.
Fig. 6.31
A graft duodenum–to–small bowel anastomosis is performed in two layers. The outer layer of the back wall is placed first, after carefully aligning the donor duodenum (blue arrow, broken blue line marks incision) and recipient small bowel (yellow arrow, yellow broken line) mark incision
11.
The duodenum and side of the bowel are opened for a corresponding length. The inner layer of the back wall is performed. The anastomosis is completed by performing the two layers of the anterior wall (Fig. 6.32).
Fig. 6.32
The duodenum and side of the bowel are opened for a corresponding length. The inner layer of the back wall is performed. The anastomosis is completed by performing the two layers of the anterior wall
6.4 Simultaneous Pancreas Kidney: Portal/Enteric Drainage
(11)
Department of Surgery, The Methodist Hospital/Cornell University, 6550 Fannin Street, Smith Tower 1661, Houston, TX 77030, USA
(12)
Department of Surgery, Louisiana State University Health Science Center, 1501 Kings Highway, Shreveport, LA 71130, USA
The major differences between the portal pancreas operation and other pancreas transplant procedures are related to the size and location of the portal tributaries in the recipient, the orientation of the pancreas, and the need to traverse the small bowel mesentery for the arterial anastomosis. The location and size of the portal vein are of utmost importance, as they determine the venous outflow from the transplant pancreas. We have learned through experience that in some patients, portal anastomosis of the donor portal vein is not advisable because of the small size of the portal tributaries. In cases where the superior mesenteric vein or its branches are small or too deeply located in a thickened mesentery, it is preferable to use systemic placement of the gland to the IVC or the iliac veins. The orientation of the gland is also important, as the donor-to-recipient anastomosis must be constructed parallel to the axis of the vein to prevent distorting the recipient vein if one attempts to construct a perfectly vertical anastomosis. Because the bowel anastomosis fixes the vein in position, the location of that anastomosis should be chosen so as not to rotate the venous anastomosis, which could increase the risk of venous thrombosis. Finally, the arterial anastomosis site should be chosen in such a way as to prevent redundancy of the arterial conduit, particularly in the donor external and internal iliac limbs. Because the pancreas is a low-flow organ, these vascular considerations are important in preventing arterial and/or venous thrombosis.
6.4.1 Operative Procedure
The operation is generally performed by an intraperitoneal approach through a midline incision (Fig. 6.33). In rare cases with extensive intraperitoneal adhesions, a retroperitoneal dissection of the superior mesenteric vein can be performed and then a peritoneal window is constructed to ensure utilization of the peritoneal surface in absorption of potential pancreatic surface leaks and preventing retroperitoneal fluid collections.
Fig. 6.33
Simultaneous pancreas kidney transplantation with portal/enteric drainage
6.4.1.1 Bench Preparation
Bench preparation of the pancreas for the portal procedure follows the same steps as in other pancreas transplant procedures: closure of the bowel ends over the staple lines, removal of retroperitoneal tissue from around the superior mesenteric artery, ascertaining hemostasis at the cut edge of the mesenteric edge overlying the uncinate process, dissection of the portal vein to ensure adequate length for anastomosis, and construction of the arterial conduit for a single donor-recipient anastomosis. The donor portal vein should be redundant over the pancreatic surface to prevent tethering of the venous anastomosis following gland perfusion. The arterial conduit is usually constructed with a segment of the common iliac and its external and internal branches. Whenever possible, the external and internal iliac branches of the arterial conduit should be shortened so that most of the distance between the pancreatic blood vessels and the recipient iliac artery is traversed by the straight (and less likely to kink) common iliac artery of the donor (Fig. 6.34).
Fig. 6.34
Construction of the arterial conduit for a single donor-recipient anastomosis
6.4.1.2 Recipient Operation
1.
With the patient in the supine position, a midline incision extending from the xiphoid to the pubic symphysis is made (Fig. 6.35). It is generally necessary to divide the falciform ligament of the liver. A thorough abdominal exploration is then performed to ascertain the absence of anatomical or pathologic anomalies that could affect the procedure.
Fig. 6.35
The recipient operation begins with a midline incision extending from the xiphoid to the pubic symphysis
2.
The transverse colon is then reflected upwards and out of the incision and wrapped in warm moist towels on the skin surface. Abdominal retractors are then placed on both sides of the wound. Bowel loops are packed in the left lateral gutter and inferiorly in the pelvis, stretching the mesenteric root. This exposes the recipient’s duodenal loop, ligament of Treitz, and the uncinate process. The superior mesenteric vein (blue arrow) with its tributaries can be seen under the thin peritoneal covering of the root of the mesentery (Fig. 6.36).
Fig. 6.36
The recipient’s duodenal loop, ligament of Treitz, and the uncinate process are exposed. The superior mesenteric vein (blue arrow) with its tributaries can be seen under the thin peritoneal covering of the root of the mesentery
3.
The peritoneum overlying the vessels is cut with the scissors or electrocautery, making sure to continuously separate the superior mesenteric vein (SMV), gently teasing it away from the peritoneal membrane to prevent its injury (Fig. 6.37). The dissection is carried in the root of the mesentery until the vein is well exposed for a distance of about 4–5 in. and the venous tributaries are dissected. Using minimal traction, the posterior aspect of the vein is exposed to ensure absence of any tributaries that could cause bleeding during the anastomosis. The main vein and all its tributaries are then encircled with thin vessel loops.
Fig. 6.37
When the peritoneum is cut, the superior mesenteric vein (SMV) is gently teased away from the peritoneal membrane to prevent its injury. The vein should be well exposed for 4 or 5 in. and the venous tributaries dissected
4.
It is important during the dissection around the vein to look for lymphatic tributaries and ligate larger lymph channels whenever possible to avoid the development of postoperative lymph leaks (Fig. 6.38). Small venous tributaries can be ligated on the vein side and electrocoagulated on the mesenteric side. Care should be exercised to avoid electrocoagulating both ends to avoid postoperative bleeding from the small branches. Following completion of the dissection, it is not uncommon for the vein to be in spasm and have a reduced diameter. In such cases, it is best to remove all vessel loops, proceed with dissection of the iliac vessels, and decide later whether the vein size permits portal anastomosis.
Fig. 6.38
It is important during the dissection around the SMV to look for lymphatic tributaries and ligate larger lymph channels whenever possible
5.
Exposure of the iliac vessels is generally done on the right side. If a prior kidney transplant has been done on the right, the left side can be used. The packing of the bowel loops is removed and the retractor is adjusted to provide maximum exposure on the right side. Mobilization of the right colon and the small intestinal mesentery is undertaken (Fig. 6.39). The right colon and intestines are then wrapped in a large towel and reflected upwards and to the left. The sigmoid colon is also covered by moist towels and retracted to the left.
Fig. 6.39
Mobilization of the right colon and the small intestinal mesentery is undertaken; the right colon and intestines are then wrapped in a large towel and reflected upwards and to the left
6.
The retroperitoneum is then opened after identification of the ureter and the gonadal vessels. These structures are gently swept medially and dissection is carried on top of the common iliac artery. The common iliac artery is exposed from the aorta to the beginning of the external iliac artery (Fig. 6.40). Gentle palpation ensures that there are no hard calcifications that could prevent a safe anastomosis. In patients with calcification, the external iliac could be dissected, or alternatively one could use the recipient aorta. As occlusion for the arterial anastomosis is generally done by a large side-biting C-clamp, enough of the common iliac vein must be dissected to ensure safe placement of the vascular clamp.
