Influence of acute hypervolemic hemodilution on pharmacodynamics of cisatracurium in patients undergoing general anesthesia / 中华麻醉学杂志

ABSTRACT

Objective To investigate the influence of acute hypervolemic hemodilution (AHH) on pharmacodaynamics of cisatracurium in patients undergoing general anesthesia. Methods Sixty ASA Ⅰ or Ⅱ patients aged 18-60 yr scheduled for major abdominal surgery under general anesthesia were randomly allocated into 2 groups (n = 30 each) control group and AHH group. Each group was further divided into 3 subgroups according to the initial dose of cisatracurium (30, 40, 50 μg/kg) . The radial artery and right internal jugular vein were cannulated. BP, HR, CVP, SpO_2, P_(ET) CO_2 and body temperature were continuously monitored. The response of left adductor pollicis muscle to TOF stimulation of ulna nerve was monitored using TOF- Watch~R SX (Organon). Both groups received 10 ml/kg multiple electrolyte solution (plasma-Lyte A) during induction of anesthesia. In group AHH 15 ml/kg 6% hydroxyethyl starch (HES) 130/0.4 solution was infused via internal jugular vein over 30-40 min in addition to plasma-Lyte A. Five minutes after completion of plasma-Lyte A or HES, cisatracurium 30, 40 or SO fig/kg was injected iv in the respective subgroups. After the maximal T_1 block was achieved, the second dose was given to reach a total dose of 100 μg/kg. The onset time, duration of clinical action, total duration of action and recovery index were recorded. The doses for 50% , 90% and 95% T_1 depression (ED_(50), ED_(90), ED_(95)) were calculated by Probit method. Results The ED_(50), ED_(90), ED_(95) of cisatracurium were significantly higher in AHH group than in control group. The onset time of cisatracurium was significantly longer but clinical and total duration of action was significantly shorter in AHH group than in control group. There was no significant difference in recovery index between the two groups. Conclusion AHH can decrease the potency of cisatracurium.