Physician predictions of graft survival following liver transplantation

Introduction. Due to the scarcity of cadaveric livers, clinical judgment must be used to avoid futile transplants. However, the accuracy of human judgment for predicting outcomes following liver transplantation is unknown. The study aim was to assess expert clinicians' ability to predict graft survival and to compare their performance to published survival models. Materials and methods. Pre-transplant case summaries were prepared based on 16 actual, randomly selected liver transplants. Clinicians specializing in the care of liver transplant patients were invited to assess the likelihood of 90-day graft survival for each case using (1) a 4-point Likert scale ranging from poor to excellent, and (2) a visual analog scale denoting the probability of survival. Four published models were also used to predict survival for the 16 cases. Results. Completed instruments were received from 50 clinicians. Prognostic estimates on the two scales were highly correlated (median r=0.88). Individual clinicians' predictive ability was 0.61±0.13, by area under the receiver operating characteristic curve. The performance of published models was MELD 0.59, Desai 0.66, Ghobrial 0.61, and Thuluvath 0.45. For three cases, clinicians consistently overestimated the probability of survival (87±10%, 89±9%, 86±9%); these patients had early graft failures caused by postoperative complications. Discussion. Clinicians varied in their ability to predict survival for a set of pre-transplant scenarios, but performed similarly to published models. When clinicians overestimated the chance of transplant success, either sepsis or hepatic artery thrombosis was involved; such events may be hard to predict before surgery.