Abstract
Patients with antiphospholipid syndrome undergoing cardiac surgery are at increased risk for thrombotic and hemorrhagic complications. We present here the management of a 68-year-old man with antiphospholipid syndrome who was scheduled for aortic valve replacement. A heparin sensitivity test was performed after anesthesia induction, and a calibration curve for blood heparin concentration and activated clotting time was created. We set a target activated clotting time of 444 s, corresponding to a heparin concentration of 3.5 U/mL. Heparin was administered at a dose of 400 U/kg, and cardiopulmonary bypass was initiated after confirming that the target activated clotting time was exceeded. After cardiopulmonary bypass weaning, 2 mg/kg of protamine was administered, resulting in a return of the activated clotting time to the pre-heparin level. Thromboelastography measurements showed citrated kaolin reaction time/citrated kaolin with heparinase reaction time values of 11.6/9.8. No additional protamine was administered, and heparin was restarted for anticoagulation management of antiphospholipid syndrome 3 h after admission to the intensive care unit. During cardiac surgery in antiphospholipid syndrome patients, evaluating coagulation status using thromboelastography combined with the heparin sensitivity test may enable safer management compared to activated clotting time-based assessment alone.