Title: Intraoperative Heparinization During Orthotopic Liver Transplantation: A Single-Center Investigation

Authors: DeAndre Guyton, Christopher Wray, Andrew Disque, Jennifer Scovotti

Background:

Some centers perform routine anticoagulation during orthotopic liver transplantation (OLT) to prevent acute thrombotic complications despite a scarcity of evidence supporting perioperative thromboprophylaxis in this surgical population [1]. Heparin has an established safety profile in cirrhosis patients [2]. However, the safety of heparin during OLT has not been definitively proven. We hypothesized that the use of intraoperative heparin would not significantly impact intraoperative bleeding and overall transfusion requirements. We planned to control for factors that are known to impact perioperative bleeding and transfusion requirements.

Methods:

In this single-center retrospective case control study, 454 adult patients underwent OLT at our center from October 2018 to April 2022. 155 patients received heparin. Average heparin dose was approximately 3500 units. Our primary outcome was total red blood cells (RBC) transfused during surgery. Secondary outcomes include mortality.

Results:

Patients had a mean age of 55 ± 13 years and a mean MELD-Na score of 36 ± 7 at the time of surgery. The study group received less total mL of RBC transfusions compared to the control group (2160 ± 2253 versus 4540 ± 4364, respectively, p<0.001). A total of 35 patients died over the study period, 11 in the study group and 24 in the control group. There was no difference in mortality between the two groups (p=.504)

Conclusion:

In our preliminary analysis, we found that intraoperative heparinization was not associated with significant bleeding as reflected by transfusion requirements. There was also no evidence that intraoperative heparinization increased the risk of postoperative mortality. We found differences between the groups in multiple variables including MELD score, surgical technique and preoperative comorbidities. In the next phase of our study, we plan to perform a multivariable analysis of our data that will incorporate these variables. Based on our single-center investigation, our eventual goal is to perform a multicenter study that would be sufficiently powered to detect differences in perioperative thrombotic complications that may be prevented with the of intraoperative heparinization during OLT.

Resources:

[1] Surianarayanan, Vignesh, Thomas J Hoather, Samuel J Tingle, Emily R Thompson, John Hanley, and Colin H Wilson. “Interventions for Preventing Thrombosis in Solid Organ Transplant Recipients.” The Cochrane Database of Systematic Reviews 2021, no. 3 (March 15, 2021): CD011557. https://doi.org/10.1002/14651858.CD011557.pub2.

[2] “Efficacy and Safety of the Use of Heparin as Thromboprophylaxis in Patients with Liver Cirrhosis: A Systematic Review and Meta-Analysis - Thrombosis Research.” Accessed March 25, 2025. https://www.thrombosisresearch.com/article/S0049-3848(13)00330-7/fulltext.