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[Heparin resistance associated with elevated factor VIII]

Natsumi Kumano1, Satoko Ikeda, Yutaka Arimori

  • 1Department of Anesthesiology, National Hospital Organization, Iwakuni Clinical Center, Iwakuni 740-8510.

Masui. the Japanese Journal of Anesthesiology
|April 18, 2008
PubMed

An 84-year-old female patient was scheduled to undergo AVR, CABG, and Maze procedure. She had a history of hypertension, cerebral infarction, and branch retinal vein occlusion. Warfarin was administered preoperatively. Before the cardiopulmonary bypass (CPB), heparin 5,000 units was administered. Activated coagulation times (ACTs) before and after CPB were 123 sec and 157 sec, respectively. Additional heparin of 5,000 units extended ACT to 221 seconds, which was not enough for the CPB. Heparin 10,000 units was added, and ACT was 157 sec. AntithrombinIII (ATIII) and platelet counts were 75% and 270,000 mm(-3), respectively. ATIII 1,500 units was administered. ACT and ATIII became 133 sec and 123%, respectively. Because heparin resistance did not respond to ATIII, the operative method was changed to off-pump CABG. A postoperative examination revealed high factor VIII activity of 263%. Other results were as follows: protein C antigen, 40%; protein S antigen, 65%; factor VII, 50%; platelet factor 4, 12%; heparin cofactor II, 104%; von Willebrand factor antigen, 181%; heparin-PF4-IgG antibody, negative; factor VIII inhibitor, negative. The low values of protein C, protein S, and factor VII may have been caused by warfarin. Other values were normal, except for the von Willebrand factor antigen.

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