Hypothermic circulatory arrest induced coagulopathy: rotational thromboelastometry analysis.

Area of Science:

• Cardiovascular Surgery
• Hematology
• Anesthesiology

Background:

• Hypothermic circulatory arrest (HCA) is a known risk factor for coagulopathy in cardiac surgery.
• The precise mechanisms and detailed coagulopathic effects of HCA remain incompletely understood.
• Rotational thromboelastometry (ROTEM) offers advanced insights into hemostasis and clot dynamics.

Purpose of the Study:

• To elucidate the detailed coagulopathic effects of HCA during cardiac surgery.
• To analyze the impact of HCA on hemostatic parameters using ROTEM.
• To compare bleeding and transfusion requirements between HCA and non-HCA groups.

Main Methods:

• Retrospective analysis of 38 patients undergoing elective cardiac surgery (12 HCA, 26 non-HCA).
• Collection of blood samples pre- and post-cardiopulmonary bypass (CPB).
• Performance of standard laboratory tests (SLTs) and four ROTEM assays (EXTEM, INTEM, HEPTEM, FIBTEM) to assess clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), and maximum clot elasticity (MCE).

Main Results:

• The HCA group exhibited significantly longer operation and hemostatic times, with no difference in CPB time.
• Perioperative bleeding and intraoperative transfusion volumes were substantially higher in the HCA group.
• ROTEM analysis indicated reduced MCE attributed to platelets in the HCA group, while fibrinogen's contribution to MCE remained unchanged. SLTs showed no intergroup differences.

Conclusions:

• HCA in cardiac surgery is associated with increased perioperative bleeding and transfusion requirements.
• ROTEM findings suggest HCA adversely affects clot firmness by impairing platelet function, contributing to coagulopathy.