**6.4. Surgical complications**

**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 tech-

**3.** Spleno-mesenteric termino-lateral anastomosis between the splenic artery and the supe-

Once the bech surgery is performed, graft is perfused with about 100 cc of preservation solu-

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,

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 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

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

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

nique of choice for its simplicity.

rior mesenteric artery of the graft.

**6.3. Pancreas implantation**

and the right iliac vein.

two continuous sutures of Prolene 5/0.

should recover a normal coloration immediately.

tion and is ready to be implanted in the recipient.

272 Organ Donation and Transplantation - Current Status and Future Challenges

advocating a more physiological position [20].

the left side increases the risk of graft thrombosis.

The absence of complications after pancreas transplantation depends largely on the detailed knowledge of both the donor and the recipient. Therefore, to minimize morbidity, postoperative care begins at the pre-operative and intraoperative periods.

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 challenge for the entire medical and surgical team.

Surgical complications are relevant since they can lead to graft loss. From 1983 to 1987, 25% of the pancreas transplants performed in the world were lost due to technical reasons [25]. However, in the last decade, the percentage of surgical morbidity has decreased drastically [6].

They represent the second cause of relaparotomy after hemorrhage. The treatment depends on the type of derivation of the exocrine secretion and the importance of the leak.

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• Graft pancreatitis: increase in serum amylase and lypase is common after pancreas transplantation, due to both factors inherent to the donor and lesions that the pancreas can suffer during extraction, preservation, implantation, and reperfusion. They are usually self-limited and do not tend to have an impact on the graft outcome. However, hyperamylasemia may be indicative of true graft pancreatitis, with symptoms that may include fever, abdominal pain, ileus, and abdominal distension. Pancreatitis that appears after the first weeks following transplantation is usually secondary to an acute rejection or infections (such as cytomegalovirus—CMV). In patients with bladder drainage, they can also be attributed to reflux of urine through the pancreatic duct. As a consequence of graft pancreatitis, fistulas, peripancreatic collections or abscesses, and pancreatic pseudocysts may occur.

**Post-transplant period**

**Complications**

Pre-trasplant Graft damage during organ procurement:

• *Duodenal lesion*

• *Hemorrhage* • *Pancreatitis*

Post-trasplant Vascular complications

Peri-transplant Acute surgical or post-surgical complications:

• *Inadequate graft perfusion* • *Cardiovascular morbidity*

Infection of surgical wound

Intra-abdominal infection Fistulas due to duodenal leaks

Urological complications Infections (bacteria, viral, fungal)

Graft pancreatitis Pancreatic pseudocysts

Panreatic leak

**Table 6.** Complications according to the time of appearance.

Incomplete healing of surgical wound

• *Vascular lesions (splenic artery, SMA, portal vein)*

• *Damage to pancreatic capsule or parenquima*

• *Vascular lesion (recipient severe atheromatosis)*

• *Graft thrombosis (60% venous, 40% arterial)*

• *Vascular complications of kidney graft (in SPK)*

Hemorrhage (intra-abdominal, bladder, gastrointestinal)

• *Late vascular complications (anastomosisstenosis, pseudoaneurisms, arteriovenous fistulas)*

In general, the main complications of pancreas transplantation, in addition to the general complications of solid organ transplants, include those that are more specific as a consequence of certain organ characteristics: low vascular flow and exocrine component.

There are a number of factors that significantly increase the risk of developing surgical complications such as a donor and recipient body mass index >30 kg/m2 , organ preservation time >20 h, cause of death of the non-traumatic donor, and to a lesser extent the intestinal drainage of pancreatic exocrine secretion.

Following are the main surgical complications:

• Vascular complications: arterial or venous thrombosis represents one of the most frequent causes of early graft loss (5–10%). The incidence of thrombosis ranges from 5 to 10% in the simultaneous transplantation of pancreas-kidney and 10–20% in isolated pancreas transplantation. It usually happens to be a venous thrombosis (60%) and appears in the first few days of transplant evolution [26].

The causes are still not fully understood: technical mistakes when performing vascular anastomoses, prothrombotic disorders and hypercoagulability, microvascular injuries produced during the period of extraction and preservation of the graft, as well as hemodynamic instability that reduce the intrinsic flow. It has also been associated with factors related to the donor, as the age and the cause of death, or a prolonged cold ischemia time.

Doppler ultrasound in expert hands is the most available image technique to diagnose thrombosis. Computed tomography is used for the evaluation of vascular anastomoses as well as to rule out the presence of other abdominal complications. Arteriography may be used to confirm the diagnosis in cases of partial or total pancreatic vessel thrombosis and even interventional radiology may be necessary.

In cases of total thrombosis, thrombolysis or thrombectomy should be attempted urgently by performing interventional radiology, and in cases where this is not possible or fails, surgical thrombectomy or transplantectomy should be performed. In partial venous thrombosis, if the thrombus occupies more than two-thrids of the lumen of the vessel, endovascular treatment may be attempted, and in the rest, heparinization. This has made it possible to reduce graft loss due to venous thrombosis to less than 1% [27].

Other vascular complications of the pancreatic graft include hemorrhage, arteriovenous fistulas, pseudoaneurysms, and stenoses of the anastomoses. **Table 6** summarizes the most important complications observed in pancreas transplant recipients for each period.

• Intestinal complications: they usually present at the anastomosis of the duodenal segment. Its incidence has decreased considerably in recent years, and currently less than 1% of the grafts are lost due to this cause [28]. Its incidence ranges at 5–20% in bladder drainage and between 5 and 8% in the intestinal drainage. Early fistulas are usually attributed to ischemia or technical failure, while later fistulas are usually caused by infections or acute rejection. They represent the second cause of relaparotomy after hemorrhage. The treatment depends on the type of derivation of the exocrine secretion and the importance of the leak.

Surgical complications are relevant since they can lead to graft loss. From 1983 to 1987, 25% of the pancreas transplants performed in the world were lost due to technical reasons [25]. However, in the last decade, the percentage of surgical morbidity has decreased drastically [6]. In general, the main complications of pancreas transplantation, in addition to the general complications of solid organ transplants, include those that are more specific as a consequence of

There are a number of factors that significantly increase the risk of developing surgical com-

time >20 h, cause of death of the non-traumatic donor, and to a lesser extent the intestinal

• Vascular complications: arterial or venous thrombosis represents one of the most frequent causes of early graft loss (5–10%). The incidence of thrombosis ranges from 5 to 10% in the simultaneous transplantation of pancreas-kidney and 10–20% in isolated pancreas transplantation. It usually happens to be a venous thrombosis (60%) and appears in the first few

The causes are still not fully understood: technical mistakes when performing vascular anastomoses, prothrombotic disorders and hypercoagulability, microvascular injuries produced during the period of extraction and preservation of the graft, as well as hemodynamic instability that reduce the intrinsic flow. It has also been associated with factors related to the donor, as the age and the cause of death, or a prolonged cold ischemia time. Doppler ultrasound in expert hands is the most available image technique to diagnose thrombosis. Computed tomography is used for the evaluation of vascular anastomoses as well as to rule out the presence of other abdominal complications. Arteriography may be used to confirm the diagnosis in cases of partial or total pancreatic vessel thrombosis and

In cases of total thrombosis, thrombolysis or thrombectomy should be attempted urgently by performing interventional radiology, and in cases where this is not possible or fails, surgical thrombectomy or transplantectomy should be performed. In partial venous thrombosis, if the thrombus occupies more than two-thrids of the lumen of the vessel, endovascular treatment may be attempted, and in the rest, heparinization. This has made it possible to

Other vascular complications of the pancreatic graft include hemorrhage, arteriovenous fistulas, pseudoaneurysms, and stenoses of the anastomoses. **Table 6** summarizes the most important complications observed in pancreas transplant recipients for each period.

• Intestinal complications: they usually present at the anastomosis of the duodenal segment. Its incidence has decreased considerably in recent years, and currently less than 1% of the grafts are lost due to this cause [28]. Its incidence ranges at 5–20% in bladder drainage and between 5 and 8% in the intestinal drainage. Early fistulas are usually attributed to ischemia or technical failure, while later fistulas are usually caused by infections or acute rejection.

, organ preservation

certain organ characteristics: low vascular flow and exocrine component.

plications such as a donor and recipient body mass index >30 kg/m2

drainage of pancreatic exocrine secretion.

days of transplant evolution [26].

Following are the main surgical complications:

274 Organ Donation and Transplantation - Current Status and Future Challenges

even interventional radiology may be necessary.

reduce graft loss due to venous thrombosis to less than 1% [27].

• Graft pancreatitis: increase in serum amylase and lypase is common after pancreas transplantation, due to both factors inherent to the donor and lesions that the pancreas can suffer during extraction, preservation, implantation, and reperfusion. They are usually self-limited and do not tend to have an impact on the graft outcome. However, hyperamylasemia may be indicative of true graft pancreatitis, with symptoms that may include fever, abdominal pain, ileus, and abdominal distension. Pancreatitis that appears after the first weeks following transplantation is usually secondary to an acute rejection or infections (such as cytomegalovirus—CMV). In patients with bladder drainage, they can also be attributed to reflux of urine through the pancreatic duct. As a consequence of graft pancreatitis, fistulas, peripancreatic collections or abscesses, and pancreatic pseudocysts may occur.


**Table 6.** Complications according to the time of appearance.

• Infections: they are frequent in this group of transplant recipients (80% throughout the first year), and they play an important role in the patient and graft survival. Diabetes, surgery, and immunosuppression are factors that predispose these patients to suffer infections of all types. Pancreas transplantation presents a risk of infection by CMV of 13–17%, largely due to the use of potent induction immnunosuppression. CMV infection is associated with increases in mortality, the rate of rejection, and the presentation of other types of infections. The incidence of intra-abdominal infections is 10–30%, most of them polymicrobial, with fungi present in less than 10% [29]. The current prophylaxis schemes (against bacterial, viral, and fungal infections), established from the moment of intervention, have managed to reduce its incidence in the short term. However, they still need to be monitored in the longer term.

Anemia is frequent among patients with ESRD. It is important to maintain adequate levels of hemoglobin (Hgb >10 mg/dl), especially in the case of postoperative bleeding. Controversy exists regarding the need for immediate anticoagulation (vide Section 8—prophylaxis).

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Both hypotension and hypertension should be avoided. A systolic blood pressure < 100 mmHG increases the risk of arterial and venous thrombosis of the graft, especially in the immediate postoperative period. On the other hand, prolonged severe hypertension can lead to a stroke or myocardial infarction and may increase the risk of intra-abdominal hemorrhage. It is advisable to maintain the systolic pressure between 120 and 160 mmHg during the first 24 h post-transplant to ensure adequate perfusion of the graft and minimize the risk

The immediate evaluation of the graft (both pancreatic and renal, in the case of SPK) can be monitored in various ways. The protocol accepted by most centers combines the use of laboratory parameters together with image tests. The decrease in blood levels of blood urea nitrogen (BUN), creatinine, amylase and lipase is required, together with blood glucose levels within normality, to consider that the grafts function correctly (in case of SPK). Blood levels of amylases and lipases provide additional information regarding pancreatic injury. In the immediate postoperative period, blood levels of pancreatic enzymes may be elevated, with normal blood glucose levels, which translates into an ischemia-reperfusion injury, and usually resolves spontaneously. In cases of exocrine drainage to urinary bladder, the level of amylases in urine can be monitored. A decrease of 50% or more is suggestive of rejection or

In the post-transplant period, radiological examinations should be perfomed to evaluate graft perfusion and exclude surgical complications, such as collections or thrombosis. Most centers rely on ultrasound as their preferred method, since it is easy to use, nontoxic, and may be pefomed as often as needed. When available, computerized tomography may provide further information, such as contrast-enhanced evaluation of arterial perfusion and venous drainage, as well as exclude possible hemorrhages. Herein, we describe in detail advantages of each

It is the initial imaging technique for control and monitoring of pancreas transplantation. The study with electronic data capture (EDC) allows to assess the size and the structure of the graft, the presence of liquid collections (study in B mode), and the perfusion of the parenchyma (resistance index), as well as the permeability of the vascular anastomoses (Doppler study). An extension of the study can also be done with the ultrasound signal enhancer, if it is considered appropriate by the sonographer who performs the study. It is advisable to make a basal study, between 24 and 48 h post-transplant, and a follow-up study, every 3–4 days until

of adverse effects.

**7.2. Graft function**

pancreatitis.

option.

**7.3. Image diagnosis**

*7.3.1. Color Doppler Ultrasound*

the patient's discharge.
