关键词: 右美托咪定, 机械通气, 苏醒期, 躁动, 清醒镇静

Abstract: 【Abstract】〓Objective〓To evaluate the efficacy of different dose of dexmedetomidine on recovery period in patients undergoing breast cancer surgery. Methods〓Eighty ASA I or Ⅱ patients undergoing modified radical mastectomy under endotracheal general anesthesia were assigned into four groups(n=20,.each)...Dexmedetomidine or equal volume of normal saline was injected intravenously 30 min before the end of operation respectively. In control group (group C), 0.9% normal saline was injected intravenously and different dose of dexmedetomidine was injected intravenously in group D1, D2 and D3 respectively (0.2 μg/kg, 0.5 μg/kg and 0.8 μg/kg). Volume control ventilation was used during operation until extubation. The time of opening eyes after operation and extubation time were recorded. Riker sedation-agitation scale and Ramsay sedation scale were recorded at the time of extubation. MAP and HR were recorded at the time of extubation (T1), 2 min after extubation (T2), 5 min after extubation (T3), 10 min after extubation (T4). Results〓Compared with group C, there were no significant differences in the time of opening eyes after operation and extubation time in group D1 and group D2, while significantly prolonged in group D3 (P<0.01). The score of Riker sedation-agitation scale in most patients in group C was 5 at the time of extubation with fast HR and high MAP. Compared with group C, the incidence of agitation was significantly decreased in group D2 and D3 (P<0.01), and cardiovascular adverse reactions significantly decreased at T1-T4. The score of Ramsay sedation scale was 2-4 in group D2. There were no significant differences in HR and MAP in intra-group D2 comparison during T0-T4 (P>0.05). The percentage of Ramsay sedation scale 5-6 was 70% in group D3, indicating excessive sedation. Conclusion〓Intravenous injection of moderate dose of dexmedetomidine (0.5 μg/kg) 30 min before the end of operation can prevent agitation caused by the endotracheal tube during recovery period in patients undergoing breast cancer surgery without delayed awakening.

Key words: Dexmedetomidine, Mechanical ventilation, Recovery period, Agitation, conscious sedation