[Dose-response relationship and serum concentrations of methohexital and hydroxymethohexital following rectal anesthesia induction with 1% and 5% methohexital solutions in children].

Dose-response-curves for rectal induction of anaesthesia in children with 1%- or 5%-methohexitone-solutions and dosages of 5, 10, 15, 20 and 25 mg/kg body wt. were obtained in 10 groups of 20 children. Methohexitone and hydroxy-methohexitone serum-levels were compared in another 23 children after application of 1%- or 5%-methohexitone-solutions at dosages of 15 and 20 mg/kg body wt. The sleep induction quota after 1%-methohexitone-solution in the 20 and 25 mg/kg body wt.-dosages was significantly higher, 20% and 25% respectively, and the mean sleep induction time shorter, 37% and 45% respectively compared with results after 5%. The change after 15 mg/kg body wt. was not significant. A study of dosages 5 and 10 mg/kg body wt. was discontinued due to insufficient effect. Methohexitone serum-levels ranged from 0.7-8 mg/l. All of the children after the use of 1%-methohexitone-solution, and only 60% after 5%-methohexitone had serum concentrations above the sleep inducing "borderline" concentration of 2 mg/l. The differences between mean methohexitone and hydroxy-methohexitone-serum-levels were not significant due to the small groups and the wide range of results. We conclude that individual dosages of 15 or 20 mg/kg body wt. 1%-methohexitone-solution should be applied according to clinical criteria such as physical and psychic status of the child.

RCT Entities:   Population Interventions Outcomes