Thiopental Sodium

How it works

It potentiates the inhibitory action of GABA at the GABA-A receptor, prolonging chloride channel opening and producing rapid central nervous system depression.

Prescribing in practice

• Causes dose-dependent cardiorespiratory depression and hypotension; have airway support and resuscitation facilities immediately available.
• Inadvertent intra-arterial injection causes intense vasospasm and tissue ischaemia, while extravasation is highly irritant due to the strongly alkaline solution.
• Contraindicated in acute porphyria, as barbiturates can precipitate an acute attack.

Monitoring

Continuous monitoring of airway, oxygenation, blood pressure and depth of anaesthesia is required throughout administration and recovery.

Counselling the patient

• This is given in a closely monitored anaesthetic or critical care setting.
• Drowsiness and impaired coordination persist after the procedure, so do not drive or operate machinery until fully recovered.

Evidence & guidelines

Thiopental is a long-established induction agent and its use is supported by anaesthetic practice standards and the SPC.