Abstract:

Objective   To detect the effect of dexmedetomidine(DEX) on general anesthesia of hypertensive patients undergoing retromastoid craniectomy for microvascular decompression(MVD) of facial nerve. Methods   48 (ASA Ⅰ-Ⅱ) hemifacial spasm patients with hypertension undergoing retromastoid craniectomy for MVD of facial nerve under general anesthesia were randomly divided into two groups: the study group and the control group. Dexmedetomidine was injected with the load dosage (1μg/kg) before anesthesia, followed by the maintaining dosage ［0.20.7μg/(kg·h)］ during anesthesia in the study group. Sodium chloride injection was pumped in the control group. Anesthesia was maintained with propofol and remifentanil. During the surgery, systolic blood pressure (SBP) was maintained 70%-80% of the baseline value by titration of anesthetic drugs and/or nitroglycerin in both groups. The mean infusion rates of propofol and remifentanil, anesthesia recovery and extubation times were observed. Results   Compared with the control group, patients in the study group required lower normalized infusion rates of propofol ［（0.076±0.014）mg/(kg·min) vs (0.092 ± 0.018)mg/(kg·min), P＜0.05］ and remifentanil ［(0.106±0.032) vs (0.131±0.030)μg/(kg·min), P＜0.05］. Anesthesia recovery times ［(5.2±2.1)min vs (9.3±2.4)min］ and extubation times ［(5.3±2.4)min vs (10.3±3.2)min］ were also significantly shorter than those in the control group (P＜ 0.05). Conclusion   Dexmedetomidine can effectively reduce the consumption of anesthetic drugs, shorten the recovery  times and hasten the extubation in the hypertensive patients during retromastoid craniectomy undergeneral anesthesia.

Key words: Dexmedetomidine;  Hypertension;  Microvascular decompression; Craniectomy;  General anesthesia