Abstract
AIM: Six-month recipient mortality after adult-to-adult living-donor liver transplantation (LDLT) remains high. Early and accurate prediction of recipient outcome and continuous monitoring of recipient severity after surgery are both essential for guiding appropriate care. This study was designed to identify early post-transplant parameters associated with 6-month mortality, and thereby to construct a discriminatory prognostic index (PI). METHODS: We retrospectively analyzed 400 consecutive primary adult-to-adult LDLTs in our center (2006-2017). Perioperative variables were comprehensively analyzed for their accuracy in predicting recipient mortality by comparing the area under the receiver operating characteristic (AUROC) of each factor. RESULTS: The AUROCs of preoperative predictive factors, for example, Model for End-stage Liver Disease (MELD) score and donor age, were 0.56 and 0.64, respectively, whereas those of post-transplant platelet count (PLT), total bilirubin (T-BIL), and prothrombin time - international normalized ratio (INR) on postoperative day (POD)-7-14 were 0.71/0.84, 0.68/0.82, and 0.71/0.78, respectively. Logistic regression analysis provided a formula: PI(POD-14) = 3.39 + 0.12 × PLT(POD-14) - 0.09 × T-BIL(POD-14) - 1.23 × INR(POD-14) , indicating a high AUROC of 0.87. Recipient 6-month survival with PI(POD-14) < 2.38 (n = 173) was 71.7%, whereas that with PI(POD-14) ≥ 2.38 (n = 222) was 97.7% (P < 0.001). The AUROCs of PI(POD-7) were as high as 0.8 in the subgroups with younger donors (<50 years of age), right lobe grafts, ABO-identical/compatible combinations, or low MELD score (<20), indicating usefulness of PI to identify unexpectedly complicated cases within the first week. CONCLUSIONS: A novel, post-transplant survival estimator, PI, accurately predicts recipient 6-month mortality within 1-2 weeks after adult LDLT. Daily monitoring of PI could facilitate early interventions including retransplantation in critically ill patients.