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

Abstract

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.

Phosphorylcholine-coated extracoporeal circulation systems affect coagulation factors during cardiopulmonary bypass insufficiently: a preliminary report

“…activity occurs by connecting heparin to the AT III on a specific pentasaccharide sequence, which primarily leads to the inactivation of coagulation factors such as F-IIa and F-Xa. [12] Although we found that the ACT values were adequate for CPB, the AT III levels were under 80 U/dl in the blood samples at T 1 and T 2 , and these low levels might have caused the continuous subclinical coagulation in our study. In fact, Despotis et al [13] highlighted that low AT III levels, particularly when they are under 80 U/dL, may be inadequate for anticoagulation.…”

Preoperative antithrombin supplementation in cardiac surgery: A randomized controlled trial

“…Low levels of AT before and during CPB are associated with a poor response to heparin, commonly defined as ''heparin resistance'' (HR), which occurs at a variable rate between 10% and 30% depending on the definition. [1][2][3][4] The use of purified AT to treat HR has been suggested as an alternative to fresh frozen plasma administration. 5 Four randomized controlled trials demonstrated the efficacy of purified AT for the treatment of HR before or during CPB, [6][7][8][9] and the recently released update (2011) of the Society of Thoracic Surgeons and Society of Cardiovascular Anesthesiologists Guidelines on Blood Conservation Clinical Practice 10 states that HR should be treated with AT concentrates before CPB (class IA).…”

Anticoagulation management during multivessel coronary artery bypass grafting: a randomized trial comparing individualized heparin management and conventional hemostasis management

“…Unexpectedly, in the present study, both techniques resulted in the same median total heparin doses. Consequently, time courses of coagulation factors (not shown) and of platelet counts were remarkably similar between groups, and followed established patterns [14][15][16]. Possible causes for a lack of difference Table 3 for correlation coefficients and P-values.…”