[Sequential changes in haemostatic activity during prolonged surgery and its alteration with continuous heparin...

We measured molecular markers to study sequential changes in the hemostatic activity and its alteration by intraoperative continuous heparin infusion in patients, undergoing surgeries of 10 hours or longer for oral cancers. The heparin was infused continuously from the beginning of microsurgery until the end of anaesthesia to maintain an activated partial thromboplastin time between 50 to 70 seconds in the heparin group. In the control group, the concentrations of thrombin-antithrombin III complex (TAT), fragment 1 + 2 (F1 + 2) and D-dimer increased, and the soluble fibrin monomer complex (SFMC) became positive 2-6 hours after the induction of anesthesia. With continuous heparinization, the changes in measured molecular markers were clearly inhibited compared with the control group. The hemostatic activities increased progressively from the early stages of surgery, and the intraoperative continuous heparin infusion was effective in suppressing the hypercoagulable state during prolonged surgery.