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CHAPTER 115: The Transplant Patient 1097

LIVER TRANSPLANTATION and encephalopathy. While previously the Child-Turcotte-Pugh (CTP)
■ INTRODUCTION scoring system lead to the creation of a more outcome validated score
score guided indications for transplantation, shortcomings with the

As we enter the sixth decade of liver transplantation, the procedure in 2002. The Model of End-Stage Liver Disease (MELD) score was
created by the United Network for Organ Sharing (UNOS) for liver
that was once considered an experimental technique fraught with transplant organ allocation. The MELD score takes into account sur-
complications has evolved into a routine therapeutic option offered rogates of synthetic dysfunction in an attempt to prioritize patients
to many patients with end-stage liver disease or acute liver failure. based on their disease severity. The MELD score is based on objective
The advancements in liver transplantation since it was first attempted lab values of total bilirubin, creatinine, and international normalized
in 1963 in Colorado have facilitated prolongation as well as enhanced ratio (INR) to risk stratify patients with cirrhosis complicated by por-
quality of life where medical management was previously limited. tal hypertension and synthetic function decline. The MELD score has
Given the advancements and success in the field, the number of been prospectively validated in several populations and is currently the
patients eligible for transplantation has outstripped the supply of scoring system of choice for prioritization of candidates with chronic
suitable livers for donation. This gap has led to other strategies to liver failure.
increase the donor pool. Living-related partial liver grafts, the use of MELD Score: 9.57 × log [Creatinine (mg/dL)] + 3.78 × log [bilirubin
extended criteria donors, transplantation of hepatitis C virus livers to (mg/dL)] + 11.2 × log (INR) + 6.43
hepatitis C recipients, and the advent of hepatitis B immunoglobulin Three-month survival is 95% with a MELD score of <15, whereas it
have allowed for transplantation where none would have previously is less than 20% in any patient with a MELD score of >40. The MELD
existed. system has led to a 12% reduction in wait list times as it identifies
■ INDICATIONS AND OUTCOMES patients (those with the lowest MELD scores) who are not benefited by
transplantation. Implementation of this new system has also decreased
65
Indications: End-stage cirrhosis complicated by portal hypertension or pretransplant mortality without having a negative impact on post-
66
compromised hepatic synthetic function is the most common indica- transplant mortality. Currently studies are underway looking at the
tion for liver transplantation accounting for over 80% of transplants addition of serum sodium to the MELD score as hyponatremia reflects
(Table 115-10). Although transplantation is not a cure of the underly- underlying hemodynamic derangements in this population that could
ing disease that may have precipitated liver disease, it addresses many be associated with the severity of their disease. Shortcomings of the
of the end-stage complications of advanced liver disease. Acute liver traditional MELD score include its underestimation of disease severity
failure can often be a devastating complication of toxic ingestion, auto- for hepatocellular carcinoma, primary biliary cirrhosis, primary scle-
immune disease, acute viral infections, and thrombosis among other rosing cholangitis, select systemic metabolic diseases associated with
causes that rapidly progress to death. In these patients, transplant is a chronic liver disease, and the presence of hepatopulmonary syndromes.
lifesaving option. In these instances (with the exception of portopulmonary hyperten-
sion), additional MELD points are assigned to these patients in order to
Chronic Liver Failure: One of the greatest challenges in transplant adjust for their increased mortality.
is identifying the optimal time for referring and listing a patient as Contraindications for transplant are minimal and are similar to
well as the creation of an allocation system that optimizes outcomes contraindications for any major surgery. Significant irreversible car-
yet is also fair to all potential recipients. The American Society of diopulmonary disease, malignancy outside of the liver within 5 years
Transplantation has attempted to develop more definitive criteria for of evaluation (excluding superficial skin malignancies), and active sub-
the nontransplant physician on the indications and timing for referral stance abuse are the absolute contraindications for transplantation. A
of liver failure patients for transplant. The traditional score for sever- variety of relative contraindications exist that are site specific. Given the
ity of liver failure was created by Child and Turcotte in 1964 that was potential for severe hemodynamic compromise, the presence of porto-
then further modified in 1972 by Pugh. The scoring system proved pulmonary hypertension or portopulmonary hypertension refractory to
to be a good predictor of outcome in patients with complications of medical management is considered a contraindication at most centers.
portal hypertension and has been the traditional scale used for assess- Data suggest that severe portopulmonary hypertension is associated
ing mortality in cirrhotic patients. 63,64 However, limitations included with a prohibitively high perioperative risk and poor clinical outcome.
the subjective nature of some parameters such as the degree of ascites The definition of severe pulmonary hypertension varies with published

TABLE 115-10 indications for Liver Transplantation
25
20
15
10
5
0
HCV Alcohol Other Cryptogenic PBC PSC FHF AIH Malignancy Alcohol + HCV

AIH, autoimmune hepatitis; FHF, fulminant hepatic failure; HCV, hepatitis C virus; PBC, primary biliary cirrhosis; PSC, primary sclerosing cholangitis. 7
Moon and Lee. 68

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