Relationships between antithrombin activity, anticoagulant efficacy of heparin therapy and perioperative variables in patients undergoing cardiac surgery requiring cardiopulmonary bypass

• Published in: Perfusion Vol. 26; no. 6; pp. 487 - 495
• Main Authors: Muedra, V, Bonanad, S, Gómez, M, Villalonga, V, Sánchez, F, Llopis, J E
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.11.2011; Sage Publications Ltd
• Subjects: Aged; Anticoagulants - pharmacology; Anticoagulants - therapeutic use; Antithrombin III - metabolism; Antithrombins - pharmacology; Antithrombins - therapeutic use; Blood Coagulation - drug effects; Blood Coagulation Tests; Cardiac Surgical Procedures - methods; Cardiopulmonary Bypass - methods; Female; Heparin - pharmacology; Heparin - therapeutic use; Humans; Male; Middle Aged; Whole Blood Coagulation Time; heparin resistance; antithrombin; cardiopulmonary bypass; extracorporeal circulation
• ISSN: 0267-6591; 1477-111X; 1477-111X
• DOI: 10.1177/0267659111412999

Introduction: A study on 149 cardiopulmonary bypass (CPB) patients was performed to elucidate possible relationships between antithrombin (AT) activity and a subject’s clinical profile or surgery characteristics. Methods: An initial dose (300 IU/kg) of heparin was administered before CPB. Additional boluses (100 IU/kg) were administered if the activated clotting time (ACT)≤460 s. AT activity and hematological parameters were determined preoperatively, during and after CPB, and at 12, 24, 36, and 48 hours post-intervention. Results: 29.5% patients required an additional dose of heparin during CPB. Preoperative AT was 96.5 ± 13.9% in all but 4 patients. AT was significantly lower during CPB and upon leaving the operating room (59.7%-80.0%). A small, but significant, inverse correlation was observed between AT at the end of CPB and the patient’s age, as well as between basal preoperative AT and total heparin administered. Conclusions: Patient’s age could be a moderate indicator of AT activity drop and low preoperative AT activity could be a sign of reduced anticoagulant efficacy of heparin during CPB.