The clinical study of the preventive effect of intravenous injection of low-dose ketamine on cough reaction caused by fentanyl during the induction of general anesthesia

Objective To investigate the preventive effect of intravenous injection of low-dose ketamine on cough reaction caused by fentanyl during the induction of general anesthesia.Methods 40 patients who were scheduled for surgery under general anesthesia,ASA grade Ⅰ~Ⅱ,aged 18 to 65 years and weighed 40 to 80kg,were randomly divided into two groups.The 20 patients in ketamine group were given ketamine 0.15mg/kg,however,the other 20 patients in control group were given equal volume of normal saline,which was finished within 10s,after 1min the patients in both groups were injected intravenously with fentanyl 3~5μg/kg,which was finished within 5s.The number and degree of patients were recorded before and after general anesthesia,and the patients'systolic and diastolic blood pressure(SBP and DBP),heart rate(HR)and pulse oxygen saturation(SPO_2)were recorded.Results After the intravenous injection of fentanyl bolus,there were no significant difference in SBP,DBP,HR between the two groups(P0.05).The incidence of cough in ketamine group was significantly lower than that of control group(P0.05),and the time of cough onset in ketamine group was later than that of control group(P0.05),however,there was no significant difference in the severity of cough between two groups(P0.05).Conclusion The injection in anvance of low-dose ketamine(0.15mg/kg)can effectively reduce fentanyl-induced cough and the incidence of cough during the induction of general anesthesia.