E6

infectious complications associated with this loss may aggravate the already precarious clinical situation. For this reason it is common to reduce the immunosuppression once the patient is re-listed so that the retransplant can be carried out under more optimal conditions.

We recently examined the survival of a large cohort of patients undergoing retransplantation at UCLA. We found that the survival of patients undergoing primary hepatic transplantation is 83% at 1 year, 74% at 5 years, and 68% at 10 years. In contrast, the survival of retransplanted patients at similar time points is significantly less, 62%, 47%, and 45% respectively. (Table E6.2) A number of variables were analyzed to determine what factors influenced outcome. We found that patient age, UNOS status, and total number of transplants were all negative prognostic factors in univariate analysis. In addition, patients retransplanted more than 30 days after their initial graft fared better than did those retransplanted between 8 and 30 days. The survival in patients transplanted within 1 week was nearly equivalent to that seen in the chronic group. This observation emphasizes the need for early recognition of patients who require early retransplantation. In contrast, pediatric retransplants performed within 1 week of the first graft fared worse than did pediatric patients retransplanted between 8 and 30 days.

To determine whether differences in illness severity, as reflected in UNOS status, could explain the poorer survival of second versus first transplants, a case-control analysis was performed comparing retransplant patients against primary transplant recipients. The transplant cases and controls were matched for age and UNOS status. Survival of retransplanted patients was still inferior to patients receiving their first graft even though the groups were objectively comparable in terms of their severity of illness.

A multivariate regression analysis was also performed on the UCLA cohort to determine independent risk factors predictive of poor patient survival. Donor cold ischemia time > 12 hours, preoperative mechanical ventilator requirement, age > 18 years, preoperative serum creatinine (Cr), and preoperative serum total bilirubin (T bili) were all independently predictive of a patient's bad outcome. Analogous findings have been noted in similar works done at the University of Pittsburgh. 11 They also identified donor age and donor gender as significant, as well as choice of primary immunosuppression. These findings have also been corroborated by the analysis of data collected at King's College Hospital in London. They saw their best results in those transplanted for chronic rejection, with an age cutoff of 39, and a better outcome occurring if the retransplanted patient was admitted from home. As in the other studies, those who were retransplanted late in the postoperative period and those with a lower serum bilirubin and creatinine fared better. These biochemical abnormalities are markers of disease severity and may well by themselves have specific effects on multiorgan function. For example, renal failure is known to be accompanied by deficiencies of cellular and humoral immunity, which predispose and aggravate the tendency to postoperative sepsis. Likewise, hyperbilirubinemia predisposes to endotoxemia, defects in cellular immunity, and Kupffer cell dysfunction. (Table E6.3)

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