UK drug analysis prints and anaesthetic adverse drug reactions.

PURPOSE

Anaesthetic drugs were selected from the Medicines and Healthcare products Regulatory Agency Drug Analysis Prints in order to determine the number and types of reported reactions and associated mortality.

METHODS

The chosen drug groups were the intravenous induction agents, the neuromuscular blocking drugs and neostigmine, the inhalational anaesthetic agents and nitrous oxide, local anaesthetic agents and a selection of analgesics agents, naloxone and midazolam and its antagonist flumazenil. From each drug file, the number and type of reactions were analysed. Mortality was calculated as a percentage of the number of deaths against patient reports.

RESULTS

A total of 11,199 reactions were analysed from 6603 patients of whom 620 (9%) died. Few drug records reported reactions from multiple constituent formulations. The majority of reactions were not allergic. The highest mortality was in the inhalational anaesthetic group. Although the greatest number of fatal events was associated with halothane, this drug is no longer used. Nevertheless the percentage remains high because cardiovascular mortality is still being reported. Local anaesthetic use was associated with the smallest percentage mortality (3%). The highest reported number of reactions was associated with the intravenous induction agents and idiosyncratic neurological and peripheral vascular reactions were linked with the use of etomidate.

CONCLUSIONS

The reporting of allergic reactions was low. The data demonstrate that induction of anaesthesia presents the highest risk of adverse drug reaction; there is also mortality from newer drugs for example, desflurane, remifentanil as well as from drugs for which there is no alternative, for example, suxamethonium.