Median effective dose of hemocoagulase agkistrodon inhibiting the bleeding after trans-bronchial lung biopsy / 中华麻醉学杂志

ABSTRACT

Objective To determine the median effective dose (ED50) of hemocoagulase agkistrodon (HCA) inhibiting the bleeding after trans-bronchial lung biopsy (TBLB).Methods ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 45-75 yr,body mass index 19-24 kg/m2,scheduled for elective TBLB,were enrolled in this study.TBLB was performed after routine anesthesia.HCA diluted in normal saline 5 ml was locally injected into the biopsy site at 2 min before surgery.The initial dose of HCA was 1.4 U.The dose of HCA was determined by up and down sequential method.Each time the dose of HCA increased/decreased in the next patient depending on whether nor not the bleeding was observed in the biopsy wound under fiberoptic bronchoscope.The ratio between the two successive concentrations was 1.2.The ED50 and 95 ％ confidence interval of HCA were calculated by Dixon's up-and-down method.Results ED50 of HCA inhibiting the bleeding after TBLB was 0.9 U,and 95 ％ confidence interval was 0.7-1.1 U.Conclusion ED50 of HCA inhibiting the bleeding after TBLB is 0.9 U.