Effects of different priming doses of propofol on fentanyl-induced cough during anesthesia induction: A preliminary randomized controlled study

Fentanyl-induced cough is not an uncommon condition during the induction of general anesthesia. A preliminary randomized controlled study was designed to observe the effects of different priming doses of propofol on fentanyl-induced cough during anesthesia induction. A total of 120 patients were randomized into 4 groups (n = 30) to receive the intravenous injection of intralipid (group I), propofol 1 mg.kg(-1) (group II), propofol 1.5 mg.kg(-1) (group III), or propofol 2 mg.kg(-1) (group IV) 1 minute before a bolus of fentanyl 2.5 microg.kg(-1). The occurrence and severity of cough were recorded for 2 minutes after fentanyl bolus. The severity of cough was graded as none (grade 0), mild (grade 1-2), moderate (grade 3-4), or severe (grade 5 or more). The average bolus time of fentanyl was 1.5 +/- 0.3 seconds in the present study. The incidence of fentanyl-induced cough was 80.0% in group I, 40.0% in group II, 6.7% in group III, and 3.3% in group IV, respectively. Groups II, III, and IV had a lower incidence and less severity of cough than group I (P < 0.05). Groups III and IV had a lower incidence and less severity of cough than group II (P < 0.05). In summary, a priming dose of more than 1 mg.kg(-1) of propofol is effective to suppress fentanyl-induced cough in a dose-dependent manner. We suggest using a priming dose of propofol 1.5 mg.kg(-1) to suppress cough during the anesthesia induction with propofol and fentanyl in clinical practice.