Rapid quantitation of plasma heparin and antithrombin III levels for cardiopulmonary bypass monitoring, using fluorometric substrate assays.
Plasma heparin and ATIII levels were determined using recently developed fluorometric substrate techniques on serial samples taken from 9 unselected patients undergoing open-heart surgery on cardiopulmonary bypass. The fluorometric assay for ATIII and established clotting and immunological methods showed a highly significant correlation (p less than 0.001). Heparin recovery was reduced in all cases, and plasma levels (fluorometric assay) demonstrated poor correlation to Whole Blood Activated Clotting Time (Hemochron) estimations. ATIII levels were dramatically reduced during bypass, and in 3 cases reached levels below 0.08 iu/ml. Heparin reversal schedules based upon empirical dosage led to excessive protamine administration by a mean factor of 3.3, as assessed by in vitro neutralization of standardized heparin concentrations.
D000990:Antithrombin III / Q000032:analysis*; D001780:Blood Coagulation Tests; D002315:Cardiopulmonary Bypass; D005260:Female; D005470:Fluorometry; D006493:Heparin / Q000097:blood*; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic
D000990:Antithrombin III; D006493:Heparin