Three point transfusion risk score in hepatectomy: an external validation using the American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP)

Background: Risk of red blood cell transfusion (RBCT) in partial hepatectomy is 17-27%; strategies to reduce transfusions can be targeted in patients at increased risk. A Three Point Transfusion Risk Score (TRS) was previously developed to predict patients' risk of transfusion during and following hepatectomy. Here, it was subject to external validation using the ACS-NSQIP database. Methods: TRIPOD guidelines were followed. A validation cohort was created with the ACS-NSQIP dataset. Risk groups for RBCT were created using the TRS: anemia (hematocrit <= 36%), major liver resection (>= 4 segments) and primary liver malignancy. Concordance index was used to assess the discrimination. The Hosmer-Lemeshow test for goodness of fit and calibration curves were used to assess calibration. Results: Of 2854 hepatectomies, 18.9% received RBCT. The TRS stratified patients from low (8.5% risk of RBCT) to very high risk (40.6%) of RBCT. The concordance was 0.68 (95% CI 0.66-0.70). Hosmer-Lemeshow test and calibration curves supported good predictive performance of the model. Conclusion: The TRS adequately discriminated risk of RBCT in an external sample of patients undergoing hepatectomy. It provides a simple method to identify patients at high transfusion risk. It can be used to tailor patient blood management initiatives and reduce the use of RBCT.