Hepatic venous pressure gradient (HVPG), serum sodium (SNa), and model of end-stage liver disease score (MELD): prognostic significance and correlations.

摘要

The Model for End-stage Liver Disease (MELD) score is a validated and valuable prognostic tool for patients awaiting liver transplantation. The MELD score is a calculation based on 3 routinely measured objective variables: the international normalized ratio, serum bilirubin, and serum creatinine. It was first developed to predict mortality after transjugular intrahepatic portosystemic shunt and was adopted in 2002 as the model by which the United States derives priority scores for cadaveric organ allocation. There are other well-established prognostic tools in end-stage liver disease, including the still valuable Child-Turcott-Pugh (CTP) scoring system that preceded the MELD for organ allocation. The CTP system included hepatic encephalopathy and ascites, subjective criteria that could be easily manipulated in a system that uses a narrow index of disease seveiity (score 7 to 15). Before MELD, the allocation system was based on CTP, admission to ICU, and waiting time. However, wait-list mortality did not correlate with waiting time. The MELD score was adopted after a federal mandate that livers should be allocated on the basis of medical urgency. The appeal of MELD is based on its objectivity and applicability to all causes of cirrhosis, and also its excellent correlation with short-term mortality risk in patients with cirrhosis. In an analysis of over 4000 transplants performed in the MELD era, Freeman and colleagues have found patient and graft survival rates to be 87.3% and 82.9%, respectively. They conclude that patient and graft survival has remained excellent in the MELD era. Since the implementation of the MELD system, sicker patients are being transplanted, time on the wait-list and wait-list mortality has fallen, and transplantation rates have increased.