Influence of different anticoagulation regimens on platelet function during cardiac surgery

Area of Science:

• Cardiovascular Surgery
• Hematology
• Pharmacology

Background:

• Qualitative platelet defects are a significant cause of bleeding after cardiac surgery.
• Anticoagulation strategies, particularly heparin use, can impact platelet function during cardiopulmonary bypass (CPB).

Purpose of the Study:

• To investigate the effects of varying anticoagulation regimens, including different heparin doses and aprotinin, on platelet function in patients undergoing coronary artery bypass grafting (CABG) with CPB.

Main Methods:

• Sixty patients were randomized into four groups receiving distinct heparin and aprotinin protocols.
• Platelet function was assessed using aggregometry with adenosine triphosphate (ADP), collagen, and adrenaline as inducers.
• Measurements of maximum aggregation and gradient were taken pre-operatively, during CPB, post-operatively, and up to one day after surgery.

Main Results:

• Groups receiving higher heparin doses (groups 2 and 3) showed significantly depressed platelet aggregation during and immediately after CPB compared to the standard heparin group (group 1).
• The addition of high-dose aprotinin (group 4) also resulted in significant platelet dysfunction.
• Platelet function showed some recovery post-operatively but did not return to baseline levels in the groups with higher heparin doses.

Conclusions:

• Higher doses of heparin and the use of aprotinin during CPB negatively impact platelet function in cardiac surgery patients.
• These anticoagulation strategies can lead to prolonged platelet dysfunction, potentially contributing to postoperative bleeding risks.