Xue F S, Liao X, Tong S Y, Liu J H, Li L, Zou Q, Luo L K
Department of Anaesthesiology, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
Br J Anaesth. 1997 Nov;79(5):612-6. doi: 10.1093/bja/79.5.612.
To evaluate the effect of acute isovolaemic haemodilution on the pharmacokinetics of vecuronium, we studied 13 patients undergoing haemodilution during surgery and 13 control patients. General anaesthesia was induced with thiopentone 4-6 mg kg-1 and fentanyl 2-4 micrograms kg-1, and maintained with enflurane and 60% nitrous oxide in oxygen. The haemodilution patients underwent major elective plastic surgery with an anticipated surgical loss of more than 600 ml. Haemodilution was achieved by drainage of venous blood and i.v. infusion of lactated Ringer's solution and 6% dextran, during which the packed cell volume and haemoglobin concentration decreased from 45% to 28.1% and from 14.7 g dl-1 to 9.1 g dl-1, respectively. After administration of a bolus of vecuronium 100 micrograms kg-1, an improved fluorimetric assay was used to measure the plasma concentrations of vecuronium for 5 h. The results showed that the disposition kinetics of vecuronium were best described mathematically by a three-compartment open model in the two groups. The mean volume of the central compartment and volume of distribution at steady state were 42.3 (SD 11.8) ml kg-1 and 168.4 (31.5) ml kg-1, respectively, in control patients, and significantly greater (55.2 (13.4) ml kg-1 and 225.9 (53.3) ml kg-1) in the haemodilution patients (P < 0.05). The elimination half-life was 50.3 (11.5) min in control patients and significantly greater (68.2 (15.1) min) in the haemodilution patients (P < 0.05). The half-lives of fast distribution and distribution, mean residual time, area under the plasma concentration curve and plasma clearance were unchanged in patients who underwent haemodilution compared with the control group.
为评估急性等容血液稀释对维库溴铵药代动力学的影响，我们研究了13例手术期间接受血液稀释的患者和13例对照患者。用4 - 6mg/kg硫喷妥钠和2 - 4μg/kg芬太尼诱导全身麻醉，并用恩氟烷和60%氧化亚氮-氧气维持麻醉。血液稀释组患者接受了预计手术失血量超过600ml的大型择期整形手术。通过静脉放血及静脉输注乳酸林格氏液和6%葡聚糖实现血液稀释，在此期间，红细胞压积和血红蛋白浓度分别从45%降至28.1%，从14.7g/dl降至9.1g/dl。静脉注射100μg/kg维库溴铵后，采用改良荧光分析法测定5小时内维库溴铵的血浆浓度。结果表明，两组中维库溴铵的处置动力学用三室开放模型数学描述最佳。对照组患者中央室平均容积和稳态分布容积分别为42.3（标准差11.8）ml/kg和168.4（31.5）ml/kg，血液稀释组患者显著更大（分别为55.2（13.4）ml/kg和225.9（53.3）ml/kg）（P<0.05）。对照组患者消除半衰期为50.3（11.5）分钟，血液稀释组患者显著更长（68.2（15.1）分钟）（P<0.05）。与对照组相比，接受血液稀释的患者快速分布半衰期、分布半衰期、平均残留时间、血浆浓度曲线下面积和血浆清除率均无变化。
