Point of Care Coagulation Testing in Patients Undergoing Major Surgery

Background: Bleeding is a frequent complication during surgery. The peri-operative administration of blood products, including packed red blood cells, thrombocytes and fresh frozen plasma (FFP), is often deemed necessary. Beside the expenses of blood products these products carry risks of infection, allergic reaction and immune-modulation. Therefore the transfusion of allogenic blood products mandates strategies to optimize the clinical decision to transfuse. Bleeding during surgery is a dynamic process; it can happen within minutes and result not only in major blood loss, but also in coagulation aberrations. The indication for a transfusion should be based on reliable coagulation studies. Traditional coagulation studies require up to 1 hour. Therefore, the decision to administer FFP is usually made in the absence of any data. Point of care testing of prothrombin time ensures that a major parameter of coagulation is readily available in the operation theatre within 3 minutes. It is fast, easy to perform, inexpensive and may enable physicians to rationally determine the need for FFP. Objective: To determine the effectiveness of point of care coagulation testing of prothrombin time to reduce the administration of FFP. Methods: Patient and assessor blind, single center randomized controlled parallel group trial in 220 patients aged between 18 and 90 years undergoing major surgery (any type, except cardiac surgery and liver transplant) with an estimated blood loss during surgery exceeding 20% of the calculated normal total blood volume or a requirement of FFP according to the judgment of treating surgeons or anesthesiologists. Patients will be randomized to usual care plus point of care coagulation testing or usual care alone without point of care testing. Primary endpoint will be the relative risk to receive any FFP peri-operatively. Significance: Point of care coagulation testing in the operation theatre may reduce the administration of fresh frozen plasma considerably, which in turn may decrease costs and complications usually associated with the administration of allogenic blood products.

Inclusion criteria

• Age between 18 and 90 years
• Major surgery
• Estimated blood loss during surgery > 20% of individual blood volume of 70ml per kg body weight
• Patients requiring FFP

Exclusion criteria

• Known hereditary coagulopathy
• Liver transplant
• Cardiac surgery
• Pregnancy
• Preoperative hemoglobin <100g/l
• Abnormal coagulation studies before surgery
• Active treatment with drugs inhibiting coagulation or platelet function