The effect of different doses of propofol on tracheal intubating conditions without muscle relaxant in children

Background and objective Situations may occur in anaesthetic practice where the use of neuromuscular blocking drugs is unsuitable or contraindicated. We investigated the use of propofol given 5 min after fentanyl to permit endotracheal intubation in children. Methods We studied the intubating conditions and cardiovascular parameters in 60 ASA I and II children. Intravenous midazolam (0.1 mg kg−1) was given as premedication 5 min before the induction of anaesthesia. The children received different doses of propofol (group I, 2.5 mg kg−1; group II, 3.0 mg kg−1; group III, 3.5 mg kg−1) preceded by fentanyl (3.0 µg kg−1) given 5 min earlier. No neuromuscular blocking agents were administered. The intubating conditions were assessed using a four-point scoring system based on the degree of difficulty of laryngoscopy, the position of vocal cords and the intensity of coughing. Results Tracheal intubating conditions were adequate in 20% of the patients in group I, in 75% of the patients in group II and in 80% of the patients in group III (P < 0.05 for group I vs. groups II and III). Haemodynamic changes were not significantly different between the groups. Conclusions Propofol (3.0 mg kg−1) preceded by fentanyl (3.0 µg kg−1) was adequate for the induction of anaesthesia in children and provided adequate tracheal intubating conditions without significant haemodynamic changes. This method represents a useful alternative technique for tracheal intubation when neuromuscular blocking drugs are contraindicated or should be avoided.