Effect of dexmedetomidine on quality of wake-up test in patients undergoing posterior osteotomy correction surgery

Abstract

Objective To evaluate the effect of dexmedetomidine on quality of wake-up test in the patients undergoing posterior osteotomy correction surgery. Methods Ninety-seven patients of both sexes, aged 17-59 yr, of ASA physical status Ⅰor Ⅱ, with body mass index 18.5-25.0 kg/m2 and global kyphosis angle>60°, scheduled for elective posterior osteotomy correction surgery under general anesthesia, were randomly divided into 2 groups using a random number table: control group C (n=46) and group D (n=51). In group D, dexmedetomidine 1.0 μg/kg was infused over 15 min before induction of anesthesia, and group C received the equal volume of normal saline instead.Anesthesia was induced with iv midazolam, propofol, fentanyl, vecuronium and dexamethasone in C and D groups.Mechanical ventilation was performed after tracheal intubation.Anesthesia was maintained with infusion of cisstracurium, propofol and remifentanil.Dexmedetomidine 0.3 μg·kg-1·h-1 was infused throughout the surgery in group D, and meanwhile normal saline was given throughout the surgery in group C. The anesthetic drugs for maintenance except dexmedetomidine were discontinued at the beginning of the wake-up test.The wake-up time was recorded and the wake-up quality was assessed.Ramsay sedation scores and Riker sedation-agitation scale scores were also recorded when all the patients were successfully awakened.The development of cardiovascular events during wake-up test and intraoperative awareness was recorded. Results The wake-up quality was significantly higher, Riker sedation-agitation scale scores were lower, Ramsay sedation scores were higher, the incidence of nausea and vomiting was lower, and no significant change was found in wake-up time in group D. No intraoperative awareness was observed in the two groups. Conclusion Dexmedetomidine can raise wake-up quality without prolonging wake-up time and with stable hemodynamics and fewer side effects in the patients undergoing posterior osteotomy correction surgery. Key words: Dexmedetomidine; Wake-up Test; Orthopedic Procedures