ABSTRACT
Objective To explore the influence of dexmedetomidine for nasal administration by three different concentrations on the stress response in patients with general anaesthesia during the peri-extubation period of gynecological surgery and to explore the optimized dosage.Methods Eighty patients undergoing general anaesthesia were randomly divided into four groups:control group (group C),and three different doses of intranasal dexmedetomidine,groups D1,D2,D3 receiving intranasal dexmedetomidine 0.6,1.2 and 1.8 μg/kg 30 min before the end of the operation,respectively.Group C was given the same volume of saline.Heart rate (HR),mean arterial pressure (MAP) and ratepressure-product (RPP) were recorded immediately after intranasal administration (T1),the end of the surgery (T2),recovery time (T3),extubation time (T4),1 min after extubation (T5),5 min after extubation (T6) and 10 min after extubation (T7).Blood samples were taken at T1,T2,T4 and T6 to detect the serum concentrations of norepinephrine (NE) and cortisol (Cor).Postoperative recovery outcomes were recorded.Results Compared with group C,MAP,HR and RPP at T3-T5 in group D1 were reduced significantly (P＜0.05).In addition,those were all decreased in groups D2 and D3 at T2-T7 (P＜0.05).Compared with group C,the serum concentrations of NE and Cor at T4 and T6 in group D1,at T2,T4 and T6 in groups D2,D3 were decreased obviously (P＜0.05).Awaken time,extubation time and PACU stay time were shortened significantly in groups C,D1 and D2 compared with group D3 (P＜0.05).Conclusion Intranasal administration of dexmedetomidine 30 min before the end of the operation could attenuate the extubation reaction and the adverse reaction of cardiovascular system during the peri-extubation period.