# Fibrinolytic Dysregulation in Regional Hemostasis During Liver Transplantation: A Viscoelastometry-Based Pilot Study

## TL;DR

This study shows that coagulation in the liver's portal vein differs from the rest of the body during liver transplants, and standard blood tests can't predict these differences.

## Contribution

The study introduces a novel comparison of systemic and regional hemostasis using viscoelastometry during liver transplantation.

## Key findings

- 45.7% of patients showed discrepancies between systemic and portal hemostasis.
- Some regional samples showed hypocoagulation with hyperfibrinolysis or hypercoagulation with fibrinolytic shutdown.
- Systemic coagulation tests failed to predict these regional variations.

## Abstract

Background/Objectives: In chronic liver disease, a rebalanced coagulation state often results in an increased risk of thrombosis, particularly in the splanchnic region. While systemic coagulation abnormalities are well documented, alterations in regional (portal) hemostasis remain underexplored. This study aimed to compare systemic and portal hemostasis during liver transplantation and to determine whether systemic parameters can accurately predict regional coagulation status. Methods: Thirty-five liver transplant recipients were included in this study. Systemic blood samples (S1–S5) were collected from the external jugular vein at five surgical time points, while portal blood samples (R3) were obtained immediately before reperfusion simultaneously with S3. All samples were analyzed using ClotPro® viscoelastic assays, conventional coagulation tests, and blood gas analysis. Results: The EX-test comparison between S3 and R3 samples revealed a discrepancy between systemic and regional hemostasis in 45.7% of patients. Among these, eight regional samples exhibited hypocoagulation characterized by coagulation factor consumption and hyperfibrinolysis. Another eight samples demonstrated hypercoagulation with fibrinolytic shutdown, which was confirmed by a fibrin-rich thrombus identified via scanning electron microscopy. Systemic samples failed to predict these regional variations. Conclusions: Regional (portal) hemostasis significantly differs from systemic coagulation and cannot be accurately predicted using systemic assays alone. These findings suggest that fibrinolytic shutdown in the portal vein may contribute to intraoperative and long-term graft damage, highlighting a potential need for regional coagulation assessment during liver transplantation.