Influence of hyperlipidemia factor on ephedrine-treated hypotension in patients undergoing epidural anesthesia

Abstract

Objective To evaluate the influence of hyperlipidemia factor on ephedrine-treated hypotension in the patients undergoing epidural anesthesia. Methods Patients scheduled for elective hysterectomy with epidural anesthesia, were divided into normal blood lipid group and hyperlipidemia group according to the fasting blood lipid level. Epidural puncture was performed at L1, 2 after replacing the cumulative body fluid loss.The hypotensive response was defined as decrease in systolic pressure (SP) 90% of the baseline value or SP>100 mmHg. The initial dose of ephedrine was 0.10 mg/kg. Up-and-down sequential allocation was used to determine the dose of ephedrine. The difference between two successive doses was 0.02 mg/kg. Each time the dose increased/decreased in the next patient according to whether SP increased or not. Probit analysis was used to determine the ED50, and 95% confidence interval (CI) of ephedrine in treating hypotension. Results A total of 114 patients were enrolled in this study, with 64 cases in normal blood lipid group and 50 cases in hyperlipidemia group. The rate of epidural anesthesia-induced hypotension was 22% (14 cases) in normal blood lipid group and 40% (20 cases) in hyperlipidemia group, and there was significant difference between two groups (P<0.05). The ED50 (95% CI) of ephedrine in treating hypotension was 0.81 (0.75-1.03) mg/kg and 1.14 (1.05-1.31) mg/kg in normal blood lipid group and hyperlipidemia group, respectively, and there was significant difference between two groups (P<0.05). Conclusion Hyperlipidemia can not only be considered as a risk factor for epidural anesthesia-induced hypotension, but also markedly decease pressor responses to ephedrine for the female patients undergoing low epidural anesthesia. Key words: Hyperlipidemias; Ephedrine; Anesthesia, epidural; Hypotension