Background: The Hypotension Prediction Index (HPI) was recently introduced and clinically validated in different surgical conditions. This prospective observational study evaluated HPI's performance in living donor liver transplant recipients under the hypothesis that HPI would be inferior to the previously reported predictability in major surgery due to the surgical characteristics of liver transplantation.
Methods: Twenty adult patients undergoing living donor liver transplantation were enrolled. HPI was monitored during the surgery with the attending anesthesiologist blinded to the HPI. The mean arterial pressure and HPI were recorded at 1-minute intervals. The area under the curve (AUC) of the receiver operating characteristic curve was calculated for the whole dataset and at each phase of liver transplantation at five, 10, and 15 minutes to analyze HPI's performance.
Results: A total of 9173 data points were analyzed. The AUC for predicting hypotension at five minutes was 0.810 (95% confidence interval [CI]: 0.780-0.840). The AUCs for predicting hypotension at 10 and 15 minutes were 0.726 (95% CI: 0.681-0.772) and 0.689 (95% CI: 0.642-0.737), respectively. The AUCs for predicting hypotension at five minutes in the preanhepatic, anhepatic, and neohepatic phase were 0.795 (95% CI: 0.711-0.876), 0.728 (95% CI: 0.638-0.819), and 0.837 (95% CI: 0.802-0.873), respectively. The HPI's performance was inferior to that previously reported in major surgery.
Conclusions: HPI in this observational study in living donor liver transplantation predicted hypotension with moderate-to-low accuracy, its predictive value being highest in the neohepatic phase and lowest in the anhepatic phase.