Factors Affecting Intraoperative Blood Transfusion Requirements during Living Donor Liver Transplantation

<b>Background</b>: Intraoperative blood transfusion (IOBT) during liver transplantation (LT) has negative outcomes, and it has been shown that an increasing number of these procedures may no longer require IOBT. Regarding living donor liver transplantation (LDLT), the literature on the pre-transplant predictors of IOBT is quite heterogeneous and deficient. In this study, we reviewed our experience of IOBT among a homogenous cohort of adult right-lobe LDLTs. <b>Methods</b>: We conducted a retrospective analysis of prospectively collected data on adult LDLT recipients between January 2018 and October 2023. Two groups were constructed (No-IOBT vs. IOBT) for the exploration of pre- and intraoperative predictors of IOBT using univariate and multivariate analyses. An ROC curve analysis was applied to identify possible cut-offs. The one-year post-LDLT overall survival was compared using the Kaplan-Meier method. A <i>p</i>-value < 0.05 was considered statistically significant. <b>Results</b>: A total of 219 adult LDLT recipients were enrolled. The No-IOBT (<i>n</i> = 56) patients were mostly males (<i>p</i> = 0.016), with higher preoperative levels of HGB (<i>p</i> < 0.001), fibrinogen (<i>p</i> = 0.005), and albumin (<i>p</i> = 0.007) and a lower incidence of pre-transplant upper abdominal surgery (<i>p</i> = 0.017), portal vein thrombosis (<i>p</i> = 0.04), hepatorenal syndrome (<i>p</i> = 0.015), and ascites (<i>p</i> = 0.02) than the IOBT group (<i>n</i> = 163). The No-IOBT group had a shorter anhepatic phase (<i>p</i> = 0.002) and received fewer intravenous crystalloids (<i>p</i> = 0.001). In the multivariate analysis, the pre-transplant HGB (<i>p</i> < 0.001), fibrinogen (<i>p</i> < 0.001), and albumin (<i>p</i> = 0.04) levels were independent predictors of IOBT, showing the following cut-offs in the ROC curve analysis: HGB ≤ 11.5 (AUC: 0.800, <i>p</i> < 0.001), fibrinogen ≤ 125 (AUC: 0.638, <i>p</i> = 0.0024), and albumin ≤ 3.6 (AUC: 0.663, <i>p</i> = 0.0002). These were significantly associated with the No-IOBT group. The one-year overall survival of the No-IOBT and IOBT groups was 100% and 83%, respectively (<i>p</i> = 0.007). <b>Conclusions</b>: IOBT during LDLT is associated with inferior outcomes. The increased need of IOBT during LT can be predicted by evaluating serum levels of hemoglobin, albumin and fibrinogen before liver transplantation.