A comparison of the effect of pretreatment with intravenous dexamethasone, intravenous ketamine, and their combination, for suppression of remifentanil-induced cough: A randomized, double-blind, placebo-controlled clinical trial

BACKGROUND: The injection of remifentanil can cause cough during induction of anesthesia. This study was designed to examine the efficacy of ketamine, dexamethasone, and their combination on remifentanil-induced cough (RIC). MATERIALS AND METHODS: One hundred and twenty patients scheduled for elective surgery were randomly assigned into four groups: Group K received 10 mg ketamine; Group D received 10 mg dexamethasone; Group KD received 10 mg ketamine in combination with dexamethasone; and Group S received saline in a similar volume, five minutes prior to the injection of remifentanil. The incidence and severity of the cough was recorded in each person. RESULTS: The incidence of RIC was significantly lower in Group KD compared to Group K, Group D, and Group S (3.3 vs. 20%, 20%, and 46.7%, respectively, P < 0.05). The severity of RIC was significantly lower in Group KD compared to Group K, Group D, and Group S (P < 0.05). There was no significant difference between Group K and Group D in this regard (P > 0.05). There was no significant difference in the onset time of coughing among the four groups (19.8 ± 1.3, 20.8 ± 0.9, 19.0 ± 1.1, and 19.9 ± 2.2 in Group K, Group D, Group KD, and Group S, respectively, P > 0.05). CONCLUSION: We found that pretreatment with 10 mg ketamine in combination with 10 mg dexamethasone five minutes prior to the injection of remifentanil could significantly reduce the incidence of RIC, and it was better than using each drug singly.