The effects of intermittent prebypass heparin dosing in patients undergoing coronary artery bypass grafting.
In this study, 10 patients (Group B) were given three consecutive prebypass doses of heparin (100 IU/kg) with a 4 min interval prior to cardiopulmonary bypass (CPB) institution. They were compared with 10 patients (Group A) receiving the standard single prebypass heparin dose (300 IU/kg). The haemostatic response and anticoagulant monitoring during the perioperative period were investigated by point-of-care and several coagulation tests. Results of both groups were also correlated to blood loss. Three patients in Group B required additional heparin during bypass as compared with six patients in Group A. This suggests that intermittent prebypass heparin dosing is more effective in maintaining adequate levels of anticoagulation during CPB. Group B had a lower mean decrease in factor VIII (13.9% versus 43.2%), fibrinogen (38.5% versus 46.6%), antithrombin III (34.7% versus 40.1%) and platelet count (23.2% versus 28.9%) during bypass while only one unit of red cell concentrate was required postoperatively as compared with four units in Group A. In one patient, high fibrinolytic assays were associated with a haemorrhagic pericardial effusion occurring beyond 24 hours postsurgery.
Grima
Carmel
C
Haematology Section, Department of Pathology, St. Luke's Hospital, G'Mangia, Malta. cjgrima@mail.global.net.mt
D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000494:pharmacology; D000990:Antithrombin III / Q000032:analysis; D016063:Blood Loss, Surgical; D001026:Coronary Artery Bypass / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D005169:Factor VIII / Q000032:analysis; D005340:Fibrinogen / Q000032:analysis; D006487:Hemostasis / Q000187:drug effects; D006493:Heparin / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019990:Perioperative Care; D019095:Point-of-Care Systems
D000925:Anticoagulants; D000990:Antithrombin III; D005169:Factor VIII; D005340:Fibrinogen; D006493:Heparin