Feasibility of different doses of dexmedetomidine required to prevent sufentanil-induced cough during anesthesia induction

Abstract

Objective To investigate the feasibility of different doses of dexmedetomidine required to prevent sufentanil-induced cough during anesthesia induction. Methods Two hundred and forty ASA Ⅰ or Ⅱ patients, aged 18-55 yr, weighing 45-78 kg, undergoing elective gynecological operations under general anaesthesia, were randomly divided into 4 groups ( n = 60 each) : Ⅰ -Ⅳ groups. Ⅱ -Ⅳ groups received iv infusion of dexmedetomidine 0.10, 0.25 and 0.50 fig/kg at a rate of 0.05 μg·kg-1·min-1 respectively before anesthesia induction. Anesthesia was induced with target-controlled infusion of propofol (target effect-site concentration 5 μg/ml) , when the BIS value reached 55, iv sufentanil 0.5 fig/kg was injected over 3 s. The occurrence and degree of cough were recorded within 1 min after sufentanil injection. Tracheal intubation was facilitated with succinylcholine 1-2 mg/kg after the observation. The adverse cardiovascular events (severe sinus bradycardia, hypotension) were also record ed from the start of dexmedetomidine infusion to 1 min after intubation. Results The incidences of cough were 25 % , 7 % , 7 % and 5 % , incidences of severe sinus bradycardia 0, 3 % , 15 % and 25 % , and incidences of hypotension 5% , 7% , 8% and 8% in Ⅰ - Ⅳ groups respectively. Compared with group Ⅰ , the incidences of cough were significantly decreased in Ⅱ - Ⅳ groups, while the incidences of severe sinus bradycardia increased in Ⅲ -Ⅳ groups (P ＜ 0.01) . There was no significant difference in the incidences of cough among Ⅱ - Ⅲ groups and in the degree of cough among the four groups (P ＞ 0.05). Conclusion Intravenous dexmedetomidine 0.10 μg/kg can be used to prevent sufentanil-induced cough during anesthesia induction. Key words: Dexmedetomidine; Sufentanil; Cough