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Technical considerations in liver transplantation: What a hepatologist needs
to know (and every surgeon should practice) Liver Transplantation Volume 11, Issue 8, Pages 861-871 August 2005 Bijan Eghtesad 1 *, Zakiyah Kadry 2, John Fung 1 1Cleveland Clinic Foundation, Cleveland, OH 2Milton Hershey Medical Center, Hershey, PA Article Text Introduction Orthotopic liver transplantation (LTX) has become an accepted means for the treatment of end-stage liver disease. Although the technique of LTX has been refined to a relatively standardized approach, the operation remains a formidable surgical challenge. As such, LTX can have numerous technical complications, in which the recipient's pretransplant condition, donor and immunologic factors, may all contribute. These risks can be minimized by appropriate ABO matching, size matching, adequate maintenance of donor physiology and graft quality and procurement. The purpose of this review is to discuss the operative procedure and to highlight some of the more important intraoperative and early and late post-operative complications. Abbreviations LTX, liver transplantation; IVC, inferior vena cava; PNF, primary nonfunction; HAT, hepatic artery thrombosis; DCD, donation after cardiac death. Historical Background The first attempt at clinical LTX was made by Thomas Starzl in Denver, in 1963[1]. The three-year-old boy with biliary atresia ultimately died of hemorrhage and coagulopathy. This was followed by six more unsuccessful LTX in Denver, Boston and Paris[1-3]. The poor outcomes of the first human LTX attempts resulted in a moratorium that extended into the summer of 1967 when a child finally underwent a successful LTX in Denver[4]. This was followed in 1968 by the opening of a LTX unit in Cambridge, the United Kingdom by Roy Calne. The first 33 LTX, of which 25 were performed in Denver and 4 in Cambridge, were later described in 1969 in a book entitled Experience in Hepatic Transplantation.[5][6] Terminology Orthotopic LTX replaces the removed liver with the transplanted allograft liver in the anatomically correct position. Heterotopic LTX is one placed in an extrahepatic site, usually at the root of the mesentery, but is of historic significance, due to poor outcomes. Auxiliary LTX is the placement of the donor liver in the presence of the native liver. Such transplants may be either orthotopic after removal of part of the native liver and placement of a portion of the donor liver, or heterotopic. Segmental LTX is placement of a portion of the donor liver into the recipient. The source of segmental grafts can be cadaveric or living donor. In the case of cadaveric segments, the graft can be a split liver graft, where the cadaveric whole liver is reduced to two smaller grafts, each retaining it's own venous drainage, portal venous inflow, hepatic artery inflow and biliary drainage. By definition, these structures must be partitioned in a way so as to maximize the likelihood of survival, but entails added risk compared to the whole cadaveric graft. Living donor segmental LTX is similar to split livers in the technical issues and complications. Operation The technique of LTX has been progressively refined since its introduction in the human in 1963, with several variations that are being applied selectively according to the patient's specific situation and/or the transplant center's routine practice. Conventional LTX involves the resection of the recipient native liver (hepatectomy) together with the retro-hepatic inferior vena cava (IVC), a short anhepatic phase, followed by the implantation of a whole deceased donor liver graft with the interposed donor IVC. Restoration of venous continuity during the implantation is achieved by an upper sub-diaphragmatic and a lower end-to-end donor to recipient IVC anastomosis; the donor to recipient portal vein and hepatic artery anastomoses are also performed in an end to end fashion. The biliary connections involve either a primary duct-to-duct technique or require the performance of a hepaticojejunostomy. Hepatectomy The standard incision for LTX has historically been a bilateral subcostal incision with an upper midline extension to the xiphoid (sometimes called an inverted Y or Mercedes incision). Other incisions have been used, however, the principle in determining the type of incision is to gain adequate exposure to the liver and to other intraabdominal structures, such as the infrarenal aorta, should the need arise. The type of incision is of paramount importance and choosing the wrong incision can make the operation difficult. The presence of previous incisions may require modifications to the planned incision, in order to avoid flap necrosis from devascularization. In the case of preexisting surgery, particular attention must be paid upon entering the abdominal cavity, as the presence of vascular adhesions can lead to both significant blood loss and/or violation of the gastrointestinal tract. Usually, the hepatectomy is the most difficult part the LTX procedure. Consequently, technical misadventures during this phase of the operation may result in significant complications. This is particularly true during the hepatectomy in patients with previous upper abdominal surgery. Excessive bleeding is the most common complication. This can be the result of carelessness, massive portal hypertension, presence of unusual collaterals (especially in the presence of portal vein thrombosis), and/or adhesions. A relatively slow, methodical and bloodless dissection translates in a much smoother operation and ironically, a considerably shorter total case time. Early portal decompression with the veno-venous bypass (see below) may aid in avoiding massive bleeding. It is particularly difficult to perform surgical hemostasis once the allograft is already in, especially if there is any degree of post reperfusion coagulopathy. Dissection of the hilum of the liver is probably the more important part of the hepatectomy. This is true especially in case of hepatectomy in living donor LTX, in cases with severe portal hypertension, and in cases with previous surgeries in the hilum of the liver. The essential goal in hepatectomy is preservation of all the hilar structures, especially hepatic artery and portal vein to be used to revascularize the new liver allograft. Approach to the hilum can commence either from the right side with dissection of cystic duct and common bile duct or from the left with dissection of the hepatic artery. In either way the essential issue is to work close to the hilar plate and try to preserve as much length of each structure as possible to facilitate as many options as possible for reconstruction at implantation. After isolation of cystic duct (in patients with gallbladder in place) and common bile duct, it is good practice to preserve the surrounding soft tissue so as not to cause damage to the bile duct blood supply. This is important to prevent postoperative bile duct ischemia and necrosis or stricture formation. An important technical issue in dissection of the hepatic artery is to start dissection of the artery at the level of right and left branch and to proceed to the confluence and to the gastroduodenal artery and finally to the common hepatic artery. The surgeon should pay attention not to put too much traction of the artery to prevent intimal dissection in the artery, which can predispose the artery to postoperative thrombosis. Dissection of the branches of the common hepatic artery will allow the surgeon to select which part of the artery will provide better size match with the donor hepatic artery. In addition, recognition of variations in the recipient anatomy of hepatic artery is helpful to prevent possibility of damage to the artery at the time of dissection. Portal vein dissection is usually done after division of the hepatic artery and bile duct. All the soft tissue around the portal vein should be dissected and removed all the way between the hilar plate to the level of head of the pancreas. Avulsion of small pancreatic branches entering the portal vein or injury to the left gastric vein can cause massive bleeding in light of portal hypertension. A potentially serious complication during hepatectomy is the injury to the right adrenal gland, which results in severe bleeding, that is difficult to control and may require adrenalectomy. Another feared complication is the injury to the right renal vein during mobilization of the infrahepatic vena cava. Dissection of the vena cava at too low a level must be avoided. Injury of the suprahepatic vena cava is an uncommon but potentially disastrous complication. Rarely, an injury of the suprahepatic cava with a resulting cuff that is too short may require control of the vena cava at the level of the diaphragm or within the pericardium, to allow placement of the vascular clamp close to or at the level of the right heart atrium. If necessary, the suprahepatic vena cava may need to the sutured closed, and venous outflow of the hepatic allograft may require a caval-atrial anastomosis. Another potential complication is the injury to the right phrenic nerve. This occurs when an excessive amount of diaphragm is included in the suprahepatic vascular clamp, particularly in the pediatric patient. This injury is usually reversible, but on occasion it can lead to permanent paralysis of the right hemidiaphragm. Anhepatic Phase Due to the fact that the conventional LTX requires the simultaneous complete occlusion of the recipient IVC and portal vein, hemodynamic instability can occur. The veno-venous bypass was developed to allow diversion of blood from the recipient IVC and portal vein directly to the patient's superior vena cava during the anhepatic phase, using heparin bonded cannulae and a motor driven bypass system.[7][8] Veno-venous bypass is used either routinely, or selectively in patients showing hemodynamic instability after a trial of clamping of the IVC and portal vein, prior to proceeding to total removal of the recipient liver. Advantages of veno-venous bypass include: --Avoidance of cardiovascular instability from reduced venous return to the heart during venous cross clamping, particularly in patients with acute liver failure or in patients with non cirrhotic indications for liver transplantation who have not developed porto-systemic venous collaterals. --Reduction of blood loss due to decompression of the portal circulation, minimizing transfusion and volume requirements. --Avoidance of mesenteric stasis and bowel edema, and subsequent development and release of anaerobic metabolism products into the general circulation and bacterial translocation. --Protection of renal function by avoiding renal venous outflow stasis. --Decompression of the portal system pressures and the avoidance of hemodynamic instability, thus allowing a safe prolongation of the anhepatic phase for meticulous hemostasis and any necessary dissection as well as facilitation of correction of any complications arising during this phase of the operation. Another advantage of the veno-venous bypass is to allow, for the first time, methodical approach to teaching trainees the complex procedure of LTX. However, the veno-venous bypass can cause complications, some of them fatal. Complications associated with veno-venous bypass have been described to occur in 10% to 30% of cases. These include seroma at the site of cannulae insertion, hematoma, wound infection and deep venous thrombosis and nerve injury. The most frequent complication is the wound lymphocoele, both in the inguinal and axillary incisions. They can be avoided by careful dissection and ligation of all lymphatics. Lymphocoeles are usually self-limiting and self-healing, but occasionally chronic lymphorrhea can be quite disabling and requiring surgical correction.[9-15] Newer approaches to percutaneous cannulation of the femoral vein and internal jugular vein may obviate the wound complications associated with cutdowns, however the risk of hematoma formation or venous perforation exists with these techniques. Mortality has also been described with air embolus at the time of decannulation as well as intracircuit clot and subsequent pulmonary embolus, the latter having occurred mainly when non heparin-bonded tubing was used.[16][17] Recently, some controversy has arisen concerning the use of veno-venous bypass, with an increasing number of transplant surgeons questioning its need.[9][18][19] This is due in part to the improved intraoperative hemodynamic management of the patient by the anesthesiology team and in part to the improved technical skills of the surgeons. The preservation of the entire retrohepatic vena cava and anastomosis of the new liver to a cuff formed from one or more of the main suprahepatic veins, has been advocated as a method of avoiding veno-venous bypass. The advantages of preserving the vena cava can be significant, but this technique (also known as the piggy-back technique, Figure 2) requires high skills and complete knowledge of and confidence with the standard LTX with veno-venous bypass.[6][20] Essentially, the technique consists in the dissection of the caudate process and right lobe of the liver from the retrohepatic vena cava, until only the right, middle and left hepatic veins remain. Subsequently, the major hepatic veins are clamped and interconnected, thus forming a cuff that can then be anastomosed to the suprahepatic vena cava of the donor liver, in an end-to-side fashion. After flushing the liver to clear the preserving solution, the infra hepatic cava of the allograft can be simply ligated. The new liver will finish by lying on top of the recipient's vena cava, but can also result in compression of the recipient's vena cava with development of thrombosis.[21][22] There are several potential advantages of the piggy-back technique, including less bleeding, less chance of adrenal gland and renal vein injury, shortening the anhepatic phase by eliminating the lower caval anastomosis, protection of renal venous outflow and function, and potentially less hemodynamic instability. In this situation, if portal cross-clamping in the patient with existing portal hypertension is well tolerated, it may be appropriate not to utilize veno-venous by-pass. There have been many modifications to the caval preserving methods used in different conditions and indications at the time of transplantation. The essential part of all these methods is to preserve the inferior vena cava with or without use of veno-venous bypass. In cases without preexisting portal hypertension (e.g. fulminant hepatitis), a temporary porto-caval shunt can be fashioned during the initiation of the anhepatic phase, to achieve mesenteric vein decompression without veno-venous bypass.[23-30] It is of importance to take advantage of the anhepatic phase and perform a thorough hemostasis of the operative area. At times, after the implantation of the new liver, there is not much exposure to get a good hemostasis in the retro-hepatic space. This is especially true in cases when the allograft is large and difficult to mobilize. Implantation Implantation of the new liver consists of several vascular anastomosis, reperfusion of the liver with the recipient blood and biliary reconstruction. Conventional way of implantation of the new liver consists of end-to end anastomoses of the supra- and infrahepatic vena cava of the donor liver to the corresponding vena caval segments in the recipient followed by end-to-end anastomosis of the portal vein of the donor liver to the recipient portal vein. Usually after completion of these anastomoses, the liver is reperfused with the recipient's blood and clamps are removed and recipient's venous circulation is reestablished through the new liver. Reperfusion of the liver can be one of the more unstable parts of the procedure. This is mainly due to the potential risk of cardiac arrhythmias, hypotension and pulmonary edema secondary to release of high concentration of potassium, and cytokines from the liver into the circulation. Use of preservative solutions with high potassium content, such as with the University of Wisconsin solution, and use of livers from expanded criteria donors, or livers with prolonged cold ischemia time can contribute to these complications. To potentially lessen or prevent these problems many surgeons flush the liver with lactated ringer or albumin or the recipient blood before connecting it to the recipient's circulation. In describing the surgical techniques involved in LTX, variations in the approach to recipients with pre-existing underlying portal vein thrombosis should be mentioned. The incidence of portal vein thrombosis in cirrhotics has been reported to vary between 0.6% to 64.1% depending upon the diagnostic study used and on patient selection.[31][32] The presence of portal vein thrombosis was previously considered a relative contraindication for LTX, a viewpoint that has since evolved. Therapeutic options in the approach during LTX to preexisting portal vein thrombosis include eversion thrombectomy of the recipient portal vein, the use of either interposition or jump venous grafts between donor portal vein and recipient portal or superior mesenteric vein (Figure 4A, B, and C), cavo-portal hemitransposition, anastomosis of the donor portal vein to an alternative recipient vein or venous collateral, and rarely arterialization of the portal vein.[33-37] Cavo-portal hemitransposition is an option utilized when extensive thrombosis of the recipient portomesenteric venous system is present and its use is rarely indicated. Arterial anastomosis between the donor and recipient arteries is usually end-to-end and the site usually varies depending on the arterial anatomy of donor and recipient and surgeon's preference. One must recognize that patients with anomalous hepatic arterial anatomy may not have a large enough common hepatic artery to use as inflow. Patients with celiac axis stenosis may also have inadequate inflow. The median arcuate ligament syndrome has been described as affecting arterial inflow in LTX. In these circumstances, the use of a donor iliac arterial conduit from the infrarenal (or occasionally supraceliac) aorta to the allograft, may be necessary (Figure 5A and B). Artificial conduits, e.g. PTFE (Gortex) grafts, should be avoided, due to the risk of thrombosis and infection. The biliary anastomosis has been referred to as the Achilles tendon of the LTX operation. There are currently two commonly practiced biliary reconstructions after LTX. The most common is the choledochocholedochostomy (duct-to-duct anastomosis) and the other is the choledochojejunostomy (to a Roux-en-Y defunctionalized intestinal loop). Duct-to-duct anastomosis is usually done over a T-tube, which remains as a stent in the duct for several months. Advantages of leaving a T-tube are observation of bile production and its quality as a sign of hepatic allograft function and easy cholangiographic access to the biliary system in cases of abnormalities in liver function tests to rule out biliary problems. The disadvantage of the T-tube is the risk of bile leak after removal of the tube, requiring emergency ERCP and decompression of the duct. Recently some transplants surgeons have questioned the need for T-tube in duct-to-duct anastomosis.[38-40] Use of stents in Roux-en-Y choledochojejunostomy is also a matter of controversy and some surgeons have stopped using it because of its complications such as retention of the stent and obstruction of the biliary system. Other historic types of biliary reconstructions include the choledochoduodenostomy and the now defunct cholecystoduodenostomy (the Wadell-Calne biliary reconstruction). Complications Complications after LTX have significant impact on outcome and cost of the procedure. The postoperative course in these patients could range from straight forward to extremely complicated, and outcome depends on the status of the recipient, donor organ and technical issues in the operation. Timely diagnosis of alterations in the normal postoperative course is the critical factor to minimize morbidity and mortality and to have better outcome. Primary nonfunction Primary nonfunction (PNF) is characterized by encephalopathy, coagulopathy, minimal bile output, and progressive renal and multisystem failure with increasing serum lactate level and rapidly rising liver enzymes and histologic evidence of hepatocyte necrosis in the absence of any vascular complication. With better donor management, operative techniques, and newer preservative solutions risk of PNF has decreased but still somewhere between 4-10% of LTX procedures may get complicated with the problem. Various donor risk factors can be implicated in primary graft dysfunction, these include prolonged cold ischemia time, unstable donor, high level of steatosis in the liver allograft, older donor, high serum sodium level in the donor, and recovered organ from DCD (donation after cardiac death/non-heartbeating) donors. Patients with initial dysfunction may recover with support but those who progress to show evidence of extrahepatic complications such as hemodynamic instability, renal failure or other organ systems dysfunction may require urgent re-transplantation.[41-43] Hepatic artery stenosis/thrombosis Angiographic evidence of greater than 50% reduction in caliber of the lumen of hepatic artery is defined as hepatic artery stenosis. This occurs in about 5% of the cases after LTX. Clinically, these patients may show increase in liver numbers or no sign at all. Sonographically, presence of low resistive index of less than 0.5 with increase in focal peak velocity are suggestive of the pathology.[44-46] Hepatic artery stenosis can be revised by surgical intervention, especially early on after LTX.[47] Percutaneous angioplasty is generally reserved for stenosis occurring several weeks after the transplant procedure with over 90% success rate.[48][49] Intimal dissection of the artery can result from too vigorous manipulation of the vessels, either in the donor or the recipient, or from direct trauma to the artery from too-forceful clamping. If not recognized early, intimal flaps will lead to arterial thrombosis. Complete thrombosis of the hepatic artery (HAT) is usually quite a dramatic complication. It can lead to acute, massive necrosis, formation of a central biloma secondary to intrahepatic duct necrosis, multiple biliary structures, or intermittent bacteremia.[50-52] Occasionally, rarely in adults but more often in children, HAT can be asymptomatic. The factors which determine whether a liver fails or survives in the face of complete HAT, is not known, however the presence of collateral circulation (e.g. from the phrenic artery via vascularized adhesions to the liver) is usually associated with a more benign course after HAT. Segmental or lobar HAT has also been described. Left HAT (usually associated with an injury to an unrecognized anomalous left hepatic artery arising from the left gastric artery) is generally benign. However, right HAT (usually associated with an injury to an unrecognized anomalous right hepatic artery arising from the superior mesenteric artery, or from technically imperfect reconstruction of the anomalous right hepatic artery at the backtable) is associated with development of biliary strictures, due to the dependence of biliary viability on the right hepatic artery. Angiography is the gold standard in diagnosis. In case of early documentation of the problem, urgent revascularization may result in arterial patency.[47][53][54] However, a significant number of patients treated in this manner may still require retransplantation due to biliary complications and persistent biliary sepsis and intraabdominal infection.[55-56] Portal vein stenosis/thrombosis Portal vein stricture can present shortly after LTX by increased production of ascites and liver allograft dysfunction. Ultrasonography and CT angiography are usually diagnostic, while superior mesenteric artery angiography with late films is the confirmatory test[57]. Treatment is by surgical intervention in early post transplantation and by percutaneous transhepatic dilatation or stenting of the stricture later after LTX. If left untreated, it can progress to complete thrombosis of the vein or severe graft dysfunction and hemodynamic instability secondary to massive production of ascites. Portal vein thrombosis is an uncommon but significant complication after adult LTX. It can manifest by rapid graft dysfunction with production of massive ascites. It could happen as a result of technical errors such as kinking or redundancy of the vein, poor mesenteric flow secondary to open collateral venous system (steal syndrome), or major anastomotic stricture or twist. Treatment is immediate surgical revascularization of the graft by thrombectomy and correction of the technical problem, ligation of large collaterals in the portal venous system, bypass grafting via the superior mesenteric vein. Otherwise, re-transplantation may be the only therapeutic option. Hepatic outflow obstruction Complications associated with vena cava stenosis include a 2.5% to 6% incidence of venous outflow obstruction (iatrogenic Budd-Chiari syndrome), caused by either rotation of the liver graft or anastomotic stricture.[58] Stenosis of the suprahepatic cava anastomosis can present with hepatic outflow obstruction in the form of liver allograft dysfunction, ascites formation, and impairment of the renal function. The problem carries a high risk for morbidity and mortality. Although hepatic outflow obstruction occurs following both standard and piggyback techniques, this is more common with the piggy-back procedure. One study showed a reduction in the incidence of venous outflow obstruction from 6% to 1% when the caval anastomosis was performed using the termination of the 3 native hepatic veins rather than only 2 hepatic veins.[22] Others have adapted a side-to-side cavo-cavoplasty in order to reduce the risk of stenosis.[25][26] Diagnosis can be made by cavagram and measurements of the venous pressure gradients proximal and distal to the anastomosis. Treatment options are by angioplasty, stent placement or surgical correction of the strictured area.[59-61] Anastomosis between the infrahepatic donor cava to the recipient cava in patients with piggy-back technique can decompress the liver in patients with outflow obstruction secondary to anastomotic narrowing between the suprahepatic donor cava and confluence of the hepatic vein in the recipient[62]. When all these measures fail, re-transplantation may be the only option. Biliary complications Biliary complications continue to be a major problem after LTX with an overall incidence of about 15-20%.[63-65] These complications range from early anastomotic leak to late stricture and obstruction, both in the extrahepatic or intrahepatic biliary system. The associated mortality rate with biliary complications is about 10% and this is mainly due to the delay in diagnosis or misdiagnosis of the problem and secondary infectious complications and graft dysfunction.[66] The biochemical abnormalities with elevation of bilirubin and canalicular enzymes (alkaline phosphatase and gamma-glutamyltransferase) are not specific, these indicators of biliary obstruction are also seen in ischemic graft injury, rejection, recurrent HCV and sepsis. Use of imaging modalities like cholangiography, both in the form of transhepatic or endoscopic, to evaluate strictures, obstruction or leak; ultrasonography, for detection of biliary dilatation; and radioisotope studies to evaluate anastomotic or cut surface leak are helpful in making an accurate diagnosis.[67-69] The most common biliary complication is biliary stenosis. This is the result of either imperfect anastomotic technique or ischemia of the bile duct, which appears as a stenotic area in the common bile duct, either at or slightly proximal to the biliary anastomosis, with proximal biliary dilatation. Recurrent bouts of cholangitis or persistent abnormal liver function tests may indicate an obstruction to bile outflow. In these cases endoscopic or percutaneous balloon dilatation of the bile duct stricture and stenting has been successful. In cases with no response, revision of the choledochojejunostomy or conversion of duct-to-duct anastomosis to choledochojejunostomy with a Roux-en-Y loop is the treatment of choice.[70-72] It has been hypothesized that the papilla of Vater is innervated by fibers coursing through the hepatic branch of the vagus, and that the hepatectomy can result in a syndrome known as ampullary dysfunction.[66] The radiological examination of the biliary tree reveals dilatation of both the donor and recipient bile ducts, distal to the choledochocholedochostomy. The treatment consists of conversion to a choledochojejunostomy, although the alternative treatment, endoscopic papillotomy, has been attempted with some success. Multiple intrahepatic strictures of the biliary tree have been described by various groups (Figure 6).[73] The causes and pathophysiology of these intrahepatic strictures have not been clearly elucidated. In many cases, the strictures seem to be associated with a hepatic artery thrombosis or stenosis and ischemia of the biliary tree is probably the etiology, especially in non-heart beating donors.[74] Preservation damage of the allograft may result in multiple intrahepatic biliary strictures, with or without biliary sludge and casts.[73] An immunologic association to a positive lymphocytotoxic positive crossmatch has also been hypothesized. In some patients who were originally transplanted for primary sclerosing cholangitis, recurrence of the disease seems a possibility.[75-79] Finally, an association of intrahepatic bile duct strictures with cytomegalovirus infection has also been reported.[80] While some patients with multiple intrahepatic strictures eventually need to be re-transplanted, others can live for years with minimal difficulties, especially if they receive chronic antibiotic prophylaxis. The most feared complication of the biliary anastomosis is the bile leak. This complication is particularly lethal in the choledochojejunostomies, since the bile collection is rapidly infected with enteric organisms, which results in an inflamed and friable operative site during attempted repair. The presence of continued enteric leak may result in mycotic rupture of the hepatic artery anastomosis. In the choledochocholedochostomies, the leaks usually occur at the exit site of the T-tube. In order to avoid this, a purse string suture should be placed around the exit site. Leakage at the T-tube exit site is usually self-containing and no treatment is necessary, as long as the distal bile duct empties well. Some surgeons have advocated not using any stenting following choledochocholedochostomy, in an attempt to avoid the risk of T-tube site leakage.[81-83] When a Roux-en-Y loop is used, bleeding can occur at the jejunojejunostomy. In about half of the cases this is a self-limiting problem. In other half, exploration for hemostasis may be necessary. This can be avoided by using a hemostatic running suture to approximate the mucosa and submucosa. A potentially lethal complication of Roux-en-Y biliary drainage is an unrecognized internal hernia through the mesentery at the jejunojejunostomy, unexplained abdominal distention, vomiting due to small bowel volvulus can progress to vascular compromise and loss of intestinal viability. Prompt recognition is critical and CT scan may reveal findings of a closed loop obstruction. Careful closure of the defect in the mesentery can reduce this complication. Bleeding Poor graft function, coagulopathy, imperfect hemostasis or slippage of a tie may result in postoperative bleeding requiring re-exploration. Postoperative bleeding is reported between 7%-15% of patients and require re-exploration in approximately half of them.[84] Even if easily controlled, postoperative bleeding leads to increased cost, morbidity and mortality. Conclusions While the results of LTX have improved dramatically over the past forty years, many of the same technical considerations have plagued the procedure since its inception. With the increasing complexity of candidate undergoing LTX, an improved understanding of the pathophysiology of donor organ preservation, reperfusion injury, improved immunosuppression, more effective diagnostic tools, and new anti-infective agents, have all contributed to a smoother post-transplant course. Nevertheless, all of these advances cannot negate a poorly performed technical procedure. NATAP http://natap.org/
http://clinicaloptions.com/hep/conf/easl2005/cs/546.asp
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Bone Loss after Liver Transplants Can Be Prevented
A
new study found that the drug used to treat osteoporosis, when used in
combination with calcium and vitamin D, can prevent the additional bone loss
that commonly occurs after liver transplants. The treatment also helped
stabilize bone loss in patients who already had osteoporosis, and helped
improve their bone mineral density (BMD).
Osteoporosis occurs in a large number of patients
with end stage liver disease, and is often worsened by the immunosuppressive
drugs normally given to prevent rejection following liver transplants. To
date, however, studies have not been conducted and no guidelines exist for
the "This is a significant improvement compared to the natural course of bone loss within the first few months after LT as reported in numerous publications." In
addition, patients with osteopenia and osteoporosis, which accounted for 72
percent of the patients in the study, remained stable on the alendronate
therapy for the first four months after transplant and showed significantly
improved BMD over the next three years, although for the most part their BMD
did not ever reach normal levels. 08/10/05
Reference http://www.hivandhepatitis.com/2005icr/ias/docs/081005_hbv_a.html
August 1, 2005 In a pilot study, a low accelerating dose regimen (LADR) of interferon plus ribavirin produced a sustained virologic response (SVR) in one quarter of patients with advanced liver disease due to HCV infection, and those patients who achieved SVR before liver transplantation tended to remain HCV-negative posttransplant. Patients with advanced liver disease from HCV infection are candidates for liver transplantation, but HCV often recurs afterwards and can lead to cirrhosis and graft loss. Achieving SVR before transplantation is desirable; however, traditional regimens of interferon or peginterferon plus ribavirin are difficult to maintain in cirrhotic patients. In this study, Everson and colleagues tested the efficacy of a LADR of interferon plus ribavirin. Eligible patients had either biopsy-proven cirrhosis or obvious clinical complications of cirrhosis such as ascites, spontaneous bacterial peritonitis, varices, or encephalopathy. Fourteen patients with bridging fibrosis on biopsy who had either abnormal bloodwork (platelet count of less than 100,000/ėL, bilirubin greater than 3.0 mg/dL, a prothrombin international normalized ratio (INR) greater than 1.2, albumin less than 3.0 g/dL) or intraabdominal collaterals or splenomegaly on radiologic imaging were also included. Patients were required to abstain from alcohol and controlled substances. Those with refractory ascites, renal failure, ongoing gastrointestinal bleeding, refractory encephalopathy, extensive hepatoma, or severe intolerance to or neuropsychiatric complications with prior courses of interferon or ribavirin were excluded. Patients who had failed a full course of previous interferon plus ribavirin were also excluded. A total of 124 patients were enrolled in the study. Initially, most patients (119) received interferon alfa-2b 1.5 MU 3 times a week plus ribavirin 600 mg daily. Five patients received peginterferon alfa-2b 0.5 ėg/kg once weekly plus ribavirin. The dose was then adjusted for each patient individually every 2 weeks until the patient reached the target standard dose or a maximally tolerated dose. Some patients required lowered dosages or shortened treatment times or both. LADR was modestly effective, and was able to be tolerated by the majority of the cohort. At the end of treatment, 46% of patients achieved HCV RNA negativity, 41% were nonresponders, and 13% discontinued treatment due to adverse events. Of those who were HCV RNA negative at the end of treatment, 47% maintained the response at 6 months post treatment, while the rest relapsed, giving an SVR rate of 22%. An additional 3 patients achieved SVR after either liver transplantation or retreatment with peginterferon plus ribavirin, bringing the overall SVR to 24%. SVR was associated with non-genotype 1, full course and duration of therapy, and HCV RNA negativity at week 24. Adverse events were common, and patients with genotype 1 infection and more advanced disease experienced the most. Twenty-two serious adverse events occurred in 15 patients, including infection, worsening ascites, encephalopathy, gastrointestinal bleeding, diabetes mellitus, severe thrombocytopenia, venous thrombosis with pulmonary embolus, and culture-negative pneumonitis. There were 4 deaths, of which the investigators considered 2 to be attributable to treatment complications (venous thromboembolism and staphylococcal sepsis). LADR was also beneficial in the long-term for some patients awaiting transplantation. A total of 90 patients in this study were listed for liver transplantation, and 47 underwent the procedure. Of these, 15 patients were HCV RNA negative before transplantation. Twelve of the 15 remained HCV RNA negative 6 months after transplantation. All of the patients who were HCV RNA positive before transplantation relapsed after transplantation. The investigators wrote, "Despite use primarily of nonpegylated interferon, and conservative application of growth factors. . . the [end of treatment response] was 30% and SVR 13% in patients with genotype 1 infection, but was 82% and 50% in patients with non-1 genotypes." They noted that the most important finding of their study was that those patients who achieved SVR before transplantation had a much higher chance of remaining HCV RNA negative posttransplantation. Although previous studies of antiviral therapy in patients with advanced disease have found prohibitively high levels of adverse events, the investigators in this study found the LADR protocol to be generally tolerable for the majority of patients, and they suggested that experienced clinicians might consider its use. References Everson GT, Trotter J, Forman L, et al. Treatment of advanced hepatitis C with a low accelerating dosage regimen of antiviral therapy. Hepatology. 2005;42:255-262.
Đ 2005 Clinical Care Options, LLC.
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http://www.hcvadvocate.org/news/newsRev/2005/HJR-2.11.html#2
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