An Evaluation of Factors Affecting Activated Coagulation Time
Journal of Cardiothoracic and Vascular Anesthesia, 05/09/2012
Bosch YPJ et al. – All these observations suggest that failure to achieve an adequate activated coagulation time (ACT) is, in general, not an indicator of antithrombin (AT) deficiency but could be affected by high platelet counts and low hemoglobin levels.Methods
- Preoperative data collection included demographics, type of preoperative medical therapy, hemoglobin, platelet count, and AT.
- Intraoperative measurements included ACT and anti-Xa activity.
- Of the 203 patients enrolled in this study, 10% (n=21) did not achieve an adequate ACT (≥400seconds) after full heparinization.
- Subnormal AT activity (55%-79%) was not related to a low ACT and a low heparin sensitivity index.
- Preoperative low-molecular-weight heparin therapy did not cause a decreased ACT response.
- However, preoperative low hemoglobin levels and high platelet counts were associated with a decreased ACT.