Effects Of Intravenous Injection Of Butorphanol On Responses To Endotracheal Extubation In Patients Undergoing Laparoscopic Cholecystectomy Under General Anesthesia At Different Times

Objective:To evaluate the effects of intravenous injection of butorphanol on responses to endotracheal extubation in patients undergoing laparoscopic cholecystectomy under general anesthesia at different times.Methods:A total of 90 patients of both sexs,aged 40⁶4 y,with body mass index of 18²5 kg/m²,of American Society of Anesthesiologists physical status I or II,scheduled for elective laparoscopic cholecystectomy under general anesthesia,were randomly divided into 3 groups（n=30 each）using a random number table:control group（group C）,preoperative administration group（group B₁）and intraoperative administration group（group B₂）.Butorphanol 20μg/kg was injected intravenously at 5 min before anesthesia induction in group B₁.Butorphanol 20μg/kg was injected intravenously at 5 min before the end of surgery in group B₂.Mean arterial pressure and heart rate were recorded before anesthesia induction（T₀）,at 1 min before endotracheal extubation（T₁）,immediately after extubation（T₂）,at 5min after endotracheal extubation（T₃）.Blood samples were collected from elbow vein（non-infusion side）for determination of plasma cortisol by enzyme-linked immunosorbent assay at T_0-2.The consumption of propofol,consumption of remifentanil,anesthesia time,surgery time,extubation time and responses to endotracheal extubation were recorded.Nausea and vomiting,dizziness,over-sedation,respiratory depression and hypotension were recorded within 30 min after endotracheal extubation.Results:1 Comparison of hemodynamic parameters and the plasma cortisol concentrations in three groups at each time:There was no significant difference among the three groups in MAP,HR and the plasma cortisol concentrations at T₀ and T₁（P>0.05）;Compared with T₁,MAP,HR and the plasma cortisol concentrations were increased at T₂ among the three groups（P<0.05）,MAP and HR were increased at T₃ in group C（P<0.05）,MAP were increased at T₃ in B₁ and B₂ groups（P<0.05）;Compaerd with group C,MAP、HR and the plasma cortisol concentrations were decreased at T₂,MAP and HR were decreased at T₃ in group B₁ and B₂ groups（P<0.05）;no significant change was found in the parameters mentioned above at T₂ and T₃in B₁ and B₂ groups（P>0.05）.2 Comparison of the incidence of endotracheal extubation responses in three groups:The incidence of endotracheal extubation responses in C,B₁ and B₂ groups were 40%,13%and 10%respectively;Compared with group C,the incidence of endotracheal extubation responses was lower in group B₁ and B₂（P<0.05）.3 Comparison of adverse reactions within 30 minutes after endotracheal extubation in three groups:Compared with group C,the incidence of postoperative nausea and vomiting was lower,the incidence of dizziness was higher in group B₁ and B₂,and the incidence of over-sedation was higher in group B₂（P<0.05）;Compared with group B₁,the incidence of over-sedation was higher in group B₂（P<0.05）.Conclusions:Intravenous injection of butorphanol 20μg/kg at 5 min before anesthesia induction and at 5 min before the end of surgery could inhibit the responses to endotracheal extubation in patients undergoing laparoscopic cholecystectomy under general anesthesia,but the drug administration was better at 5 min before anesthesia induction.