The activated clotting time in cardiac surgery: should Celite or kaolin be used?

Objectives: Both kaolin- and Celite-activated clotting times (ACT) are used to guide anticoagulation during cardiopulmonary bypass. It is unknown whether these methods lead to similar management procedures for anticoagulation in patients and are thus interchangeable in terms of bias, precision and variability.

Methods: We randomized 97 patients undergoing coronary artery bypass grafting or aortic valve replacement to either kaolin- or Celite-guided anticoagulation.