Suxamethonium Modified by Tetrahydroaminacrine

Abstract

Two hundred anaesthetics have been given in which tetrahydroaminacrine has been used to modify the action of suxamethonium given by intermittent injection. Tetrahydroaminacrine extends the time scale of the intermittent suxamethonium technique, making this more convenient and successful in practice. Furthermore, suxamethonium afterpains are reduced to insignificant proportions. The arousal time seems to be lessened. The risk of dual block is diminished. Tetrahydroaminacrine combined with intermittent suxamethonium is found to be an excellent technique for Caesarean section and for forceps delivery and for emergency abdominal surgery especially in poor-risk patients.

Dual Block Following Tacrine and Suxamethonium

“…Since its introduction into clinical anaesthetic practice (Gordh and Wahlin, 1961) tacrine is now widely used to extend die action of suxamethonium. It has been argued that by reducing the total dose of suxamethonium this technique minimi7.es the iisk of the development of dual block (Barrow and Smethurst, 1963;Speirs, 1966;Older, Harris and Mitchard, 1966). This would be an important advantage if the development of dual block depended only on dosage.…”

“…It has already been established that dual block does occur in patients in whom small doses of suxamethonium are potentiated with tacrine (Smart, 1964;Older, Harris and Mitchard, 1966). Other workers have had difficulty in restoring adequate respiration (McCaul and Robinson, 1962;Barrow and Smethurst, 1963). The purpose Present address: Department of Anaesthetics, Royal Infirmary, Glasgov, Scotland.…”

The Use of Tacrine and Suxamethonium in Anaesthesia for Caesarean Section

“…The duration of action of a single small dose of suxamethonium may be prolonged by injection of tacrine (THA, Romotal) an anticholinesterase drug, the clinical use of which has been reported by McCaul and Robinson (1962), Barrow and Smethurst (1963) and Smart (1964).…”