Thromboelastography Parameters Suggestive of Hypercoagulability and its Correlation with Thrombotic Complications in Liver Transplantation- A Retrospective Study

Abstract

Introduction: Conventional coagulation parameters like, Prothrombin Time (PT), International Normalised Ratio (INR) reflects only the synthesis or status of procoagulant factor levels. Whereas, Thromboelastograph (TEG) reflects ongoing coagulation process and helps in identifying hypocoagulable or hypercoagulable status. The hypercoagulable TEG parameters in the perioperative period can guide the physicians to prevent adverse thrombotic complications, instead of depending on the Conventional Coagulation Tests (CCTs), which has the potential to mislead and may delay appropriate clinical interventions. Aim: To establish, if correlation exists between TEG parameters suggestive of hypercoagulability and the occurrence of perioperative thrombotic complications and also to see if CCT correlates with hypercoagulable TEG parameters in liver transplantation. Materials and Methods: This was a retrospective analysis which was done in 32 patients of Diseased Donor Liver Transplantion (DDLT), from August 2018 to September 2019 at tertiary care centre in Chennai, Tamil Nadu, India. Data were analysed for correlation with hypercoagulable TEG parameters and perioperative thrombotic events. Thromboelastograph parameters were also compared with CCT like INR, platelet count. The Mann-Whitney U-test was considered significant if p-value <0.05, at 95% confidence interval. Results: Amongst the aetiology of the transplanted patients (32), the highest number of patients in the present study had alcoholic liver disease {n=11 (34.37%}. A comparison of paired G values with International Normalised Ratio (INR) showed that there was no significant correlation between G value and INR {r= -0.2, p-value=0.47 (Spearman’s rank correlation)}. The G values were compared with platelet counts and a moderate correlation was found (r=0.62, p-value <0.001). The patients with high G traces had platelet counts of normal reference range. There was no correlation between the R time and INR (r-value=0.04), (p-value=0.32). Conclusion: Thromboelastograph parameters suggestive of hypercoagulability can be useful to predict the occurrence of thrombotic complications in liver transplant surgery. The present study found a moderate correlation was seen between the G value in TEG and platelet counts. No correlation was present between r value and INR value. There is always a possibility of aggravating the thrombotic potential, if the management is solely based upon the PT, INR, platelet count values.

Keywords

• international normalised ratio
• point of care coagulation tests
• prothrombin time
• thromboelastography
• thrombotic complications