Effects Of The Small Dosage Of Dexmedetomidine Combined With Remifentanil On Cough During Extubation Under General Anesthesia

Objective:To investigate the effect of small-dose dexmedetomidine combined with remifentanil on cough during extubation under general anesthesia.Methods:90 cases of laparoscopic cholecystectomy under total intravenous anesthesia were randomly divided into two groups:dexmedetomidine group?group D?and saline group?group C?.30 mins before the end of the operation,the intravenous infusion of dexmedetomidine in group D was 0.30?g/kg?in 5 mins?.The group C was the same dose of saline as in D group.Anesthesia induction:midazolam,sufentanil,cis-atracurium,etomidate,anesthesia maintenance:propofol,remifentanil.It was recorded that the heart rate?HR?,mean arterial pressure?MAP?and blood oxygen saturation?SpO₂?at time points of entering the operating room?T0?,immediately before administration?T1?,5 min after extubation?T3?.Plasma concentrations of epinephrine?E?and norepinephrine?NE?were measured at T0,T3.It was also recorded that the incidence of cough?no cough,mild cough and severe cough?,the time of opening eyes,recovery time of spontaneous breathing,withdrawal time and directional force recovery time of the two groups and pain,postoperative nausea and vomiting.the incidence of adverse reactions including hypertension,bradycardia,residual sedative effect and memory of extubation.Results:At time points T2 and T3,HR and MAP were lower than T0 in both groups?P<0.05?.There were no significant differences in HR and MAP between the two groups at time T0and T1?P>0.05?,and the differences in HR and MAP between the two groups at time T2and T3 were lower than those in the C group?P<0.05?.SpO2 in the D group at time T3was slightly lower than that in the C group,but the differences were not statistically significant?P>0.05?.There was no significant difference in plasma E and NE concentrations at T0 between the two groups?P>0.05?.E and NE concentrations in group D at T3 were lower than those in group C at T0,and the difference was statistically significant?P<0.05?.The incidence of non-choking cough in group D was higher than that in group C?56%,9%?,the incidence of mild cough was lower than that in group C?42%,71%?,and the incidence of severe cough was also significantly reduced?2%,20%?,with statistically significant differences?P<0.05?.The open eye time,spontaneous breathing recovery time,extubation time,directional force recovery time,and Ramsay sedation score10min after extubation in group D were all greater than those in group C,but the difference was not statistically significant?P>0.05?.The incidence of pain,nausea and vomiting in group D was lower than that in group C,and the difference was statistically significant?P<0.05?.The incidence of extubation memory in group D was lower than that in group C,and the difference was statistically significant?P<0.05?.Conclusion:Dexmedetomidine can effectively reduce cough during extubation and maintain the hemodynamic stability when it is intravenous with remifentanil at 0.3?g/kg 30 mins before the end of the operation.