Background: Intraoperative circulatory risk factors are associated with unfavorable outcomes after living donor liver transplantation (LDLT). We investigated whether the preoperative neutrophil-to-lymphocyte ratio (NLR) can predict intraoperative circulatory risks.
Material and methods: The perioperative data of 276 patients who underwent LDLT were reviewed retrospectively. The intraoperative circulatory risk score (ICRS) was calculated using the inotropic score, hypotension, blood transfusion, oliguria, and change in serum lactate during LDLT. Perioperative variables including NLRs were compared between the high (≥3.0) and low (<3.0) ICRS groups, and a predictive model for high ICRS was developed.
Results: A high ICRS was associated with poor preoperative physical condition and unfavorable postoperative outcomes. The NLR progressively increased during the LDLT perioperative period. However, only preoperative NLRs differed significantly between the high and low ICRS groups (6.2 vs. 3.9, respectively; p<0.05). The predictive accuracy of the NLR (area under the receiver operator curve, 0.635) did not differ from those of the model for end-stage liver disease (MELD) and Child-Pugh-Turcotte scores. After multivariate adjustment, preoperative NLR ≥3.8 was identified as an independent predictor of high ICRS (risk ratio 3.15; p=0.004) together with preoperative hemodialysis and intraoperatively administered calcium chloride.
Conclusions: Intraoperative circulatory risks are associated with several detrimental outcomes following LDLT. The preoperative NLR is predictive of intraoperative circulatory risks.