Induction characteristics of thiopentone/suxamethonium, propofol/alfentanil or halothane alone in children aged 1-3 years.

The aim of this study was to compare the effect of three different induction techniques, with or without neuromuscular block, on tracheal intubation, haemodynamic responses and cardiac rhythm. Ninety children, aged 1-3 years, undergoing day-case adenoidectomy were randomly allocated to three groups: group TS received thiopentone 5 mg kg-1 and suxamethonium 1.5 mg kg-1, group H 5 Vol.% halothane and group PA alfentanil 10 micrograms kg-1 and propofol 3 mg kg-1 for induction of anaesthesia. No anti-cholinergics were used. Holter-monitoring of the heart rate and rhythm was started at least 15 min before induction of anaesthesia and continued until 3 min after intubation. Tracheal intubation was performed by an anaesthetist blinded to the induction method and judged as excellent, moderate or poor according to ease of laryngoscopy, position of vocal cords and incidence of coughing after intubation. Tracheal intubation was successful at the first attempt in all children in groups TS and H and but only in 80% in group PA (P = 0.001). Intubating conditions were excellent in 22 (73%), 22 (73%) and one (3%) of the patients in groups TS, H and PA, respectively (P = 0.001). Cardiac dysrhythmias (supraventricular extrasystole or junctional rhythm) occurred in two (7%) patients in groups PA and H each (NS). Bradycardia occurred in 0 (0%), four (14%) and six (21%) children in groups TS, H and PA, respectively (P = 0.007 PA vs. TS, P = 0.03 H vs. TS). In conclusion, induction of anaesthesia with propofol 3 mg kg-1 and alfentanil 10 micrograms kg-1 without neuromuscular block did not provide acceptable intubating conditions in children 1-3 years, although it preserved arterial pressure better than thiopentone/suxamethonium or halothane. Cardiac dysrhythmias were few regardless of the induction method.