Improving the induction characteristics of methohexitone. A study of the effect of adding thiopentone to methohexitone.

Author(s): Raphael JH, Bexton MD

Affiliation(s): Department of Anaesthetics, Pilgrim Hospital, Boston, Lincolnshire.

Publication date & source: 1994-04, Anaesthesia., 49(4):338-40.

Publication type: Clinical Trial; Randomized Controlled Trial

A double-blind, randomised, controlled study was undertaken to investigate the effects on injection pain and excitatory phenomena of adding thiopentone to methohexitone. One hundred and twenty unpremedicated, day-case patients received one of four induction regimens: unmodified 1% methohexitone, or a mixture of 2.5% thiopentone and 1% methohexitone in ratios of 1:1, 1:3 or 1:9 by volume. The addition of one part of thiopentone to three parts of methohexitone produced a mixture which significantly reduced the occurrence of pain and discomfort compared with methohexitone alone from 67% to 13% (p < 0.01) and reduced the occurrence of excitatory effects from 50% to 13% (p < 0.01).