Immunologic impact and clinical outcomes after surgical exposure to bovinethrombin

Objective To determine prospectively the immunologic response and adverse clinical ev ents in surgical patients exposed to bovine thrombin during cardiac surgica l procedures. Summary Background Data Topical bovine thrombin is used extensively as a hemostatic agent during ca rdiovascular surgery. Antibodies developing after exposure to bovine thromb in have been anecdotally associated with hemorrhagic complications. Methods One hundred fifty-one patients undergoing cardiac surgical procedures were prospectively recruited for this study before surgical exposure with topica l bovine thrombin. Immunoassays were used to determine antibody levels agai nst both bovine and human coagulation proteins before and after exposure to bovine thrombin. Alterations in coagulation assay parameters and adverse c linical events were followed in all patients enrolled in the study. Results Baseline elevated antibody levels to one or more bovine coagulation protein s were observed most frequently in patients with a prior history of a surgi cal procedure during which bovine thrombin is frequently used. More than 95 % of patients developed a seropositive response to bovine coagulation prote ins, and 51% manifested elevated antibody levels to the corresponding human coagulation proteins after bovine thrombin exposure. Postoperative coagula tion abnormalities were more common in patients with antibodies to human co agulation proteins. Patients with multiple elevated antibody levels to bovi ne proteins before surgery were more likely to sustain an adverse clinical outcome after surgery. Using a logistic regression model, the adjusted odds ratio for sustaining an adverse event with multiple elevated antibody leve ls to bovine proteins before surgery was 5.40. Conclusions Bovine thrombin preparations are highly immunogenic and appear to be associ ated with an increased risk for adverse clinical outcomes during subsequent surgical procedures. The clinical safety of these commonly used preparatio ns needs to be reassessed, and reexposure to these agents should likely be avoided.