Table 4. Reproducibility of HMT [s] Measurements^*and their Correlation to Chromogenic Heparin Anti-Xa Activity^†during Complicated Cardiac Surgery with Cardiopulmonary Bypass^‡in Patients Treated with Coumadin (group II^cou)

Data are mean ± SD; target ACT = 480s (heparin dose–response assay); 10 patients (7 men, 3 women, ASA III–IV, NYHA IV, mean age 73 ± 6.3 yr); HMT I/II = HMT analyzers I and II (n = 484). HMT baseline = 159 ±5.2 s (HMT I, n = 20) and 147 ± 4.9 s (HMT II, n = 20); SEM–HMT I/II = 8.7 ± 1.2; within-analyzer difference ≤ 4 % of the mean value; between-analyzer P  values = 0.001–< 0.05. Surgical procedures = three heart transplantation; two bilateral lung transplantation; one closure of infarction ventricular septal defect plus three vessel CABG; one aortic and mitral valve replacement plus tricuspid valve reconstruction; two aortic valve replacement plus three-vessel CABG; one aortic arch aneurysm replacement in deep hypothermic cardiac arrest. 24 h blood loss = 623 ± 1,230 ml (range 415–1435 ml); transfusion requirement = 2.35 ± 1.24 U packed erythrocytes, 2.51 ± 0.74 U fresh frozen plasma; 0.1 ± 0.26 U random donor platelets.

* s, performed in duplicate on two analyzers in parallel.

† U/ml, reference method.

‡ 190–320 min, with aprotinin.

HMT = heparin management test, Anti-Xa= antifactor Xa; SEM = standard error of the mean, CPB = cardiopulmonary bypass; CABG = coronary artery bypass graft.