Satoshi Matsushita1, Akinori Kishida2, Yoshihito Wakamatsu2, Hiroshi Mukaida2, Hirohide Yokokawa3, Taira Yamamoto4, Atsushi Amano4. 1. Faculty of Medicine, Department of Cardiovascular Surgery, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. saty-m@juntendo.ac.jp. 2. Department of Medical Engineer, Juntendo Hospital, Tokyo, Japan. 3. Faculty of Medicine, Department of General Medicine, Juntendo University, Tokyo, Japan. 4. Faculty of Medicine, Department of Cardiovascular Surgery, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Abstract
OBJECTIVES: Initiation of cardiopulmonary bypass (CPB) for open-heart surgery requires that heparin be administered and reach an adequate value of activated clotting time (ACT). We previously introduced a new heparin formula that considered the preoperative ACT. In this study, we determined other factors affecting ACT. METHODS: Adult patients who underwent cardiac surgery using CPB were divided into two groups according to their ACT value after the initial administration of heparin during surgery. ACT above 450 s was defined as "Reach", and this group was compared to the "Short" group with ACT below 450 s. RESULTS: The Reach and Short groups included 334 (64.7%) and 182 (35.3%) cases, respectively. Univariate analysis indicated that preoperative heparin use, age ≥ 80 years, New York Heart Association classification 4, white blood cell counts above the higher limit, hematocrit below the lower limit, platelet cell counts below the lower limit, low albumin levels, moderate renal dysfunction, high C-reactive protein levels, high brain natriuretic peptide levels, and moderate deterioration of left ventricular ejection fraction were associated with the effects of heparin. Multivariate analysis revealed that age ≥ 80 years (odds ratio [OR] 2.53, 95% confidence interval [95%CI] 1.41-5.24), New York Heart Association classification 4 (OR = 4.44, 95%CI 1.59-15.35), and platelet count below the lower limit (OR 0.37, 95%CI 0.31-0.85) were associated with the effects of heparin. CONCLUSION: Old age, heart failure, and lower platelet counts affected heparin activity. The dose of heparin should be considered in those patients to reach the target ACT.
OBJECTIVES: Initiation of cardiopulmonary bypass (CPB) for open-heart surgery requires that heparin be administered and reach an adequate value of activated clotting time (ACT). We previously introduced a new heparin formula that considered the preoperative ACT. In this study, we determined other factors affecting ACT. METHODS: Adult patients who underwent cardiac surgery using CPB were divided into two groups according to their ACT value after the initial administration of heparin during surgery. ACT above 450 s was defined as "Reach", and this group was compared to the "Short" group with ACT below 450 s. RESULTS: The Reach and Short groups included 334 (64.7%) and 182 (35.3%) cases, respectively. Univariate analysis indicated that preoperative heparin use, age ≥ 80 years, New York Heart Association classification 4, white blood cell counts above the higher limit, hematocrit below the lower limit, platelet cell counts below the lower limit, low albumin levels, moderate renal dysfunction, high C-reactive protein levels, high brain natriuretic peptide levels, and moderate deterioration of left ventricular ejection fraction were associated with the effects of heparin. Multivariate analysis revealed that age ≥ 80 years (odds ratio [OR] 2.53, 95% confidence interval [95%CI] 1.41-5.24), New York Heart Association classification 4 (OR = 4.44, 95%CI 1.59-15.35), and platelet count below the lower limit (OR 0.37, 95%CI 0.31-0.85) were associated with the effects of heparin. CONCLUSION: Old age, heart failure, and lower platelet counts affected heparin activity. The dose of heparin should be considered in those patients to reach the target ACT.