Is There An Ideal Prehospital Drug Treatment for Acute Cyanide Poisoning?

Cyanide, due to its toxicity and prevalence in a variety of industries, is a suitable agent for terrorists or disaffected persons to use as a weapon of terror. New Zealand’s National Poisons Centre lists five cyanide antidotes. This review aimed to identify whether there is an ideal pre-hospital drug treatment for acute cyanide poisoning. Methods Literature less than 10 years old was selected after a keyword search. The articles were reviewed for specific positive and negative properties of each antidote. Results Thirty-nine articles were reviewed of which four were excluded. Results varied, with hydroxocobalamin scoring highly on effectiveness, with limited negative effects. It also demonstrated positive haemodynamic effects, suitability in cases involving trauma, carbon monoxide (CO), smoke inhalation casualties and was safe for pre-hospital use. Sodium nitrite, followed by dicobalt edetate had the next highest scores for efficacy. However, both scored negatively for their effects on blood, causing hypotension and toxicity, and they are unsuitable for trauma, CO or smoke inhalation casualties. Sodium thiosulphate, with a moderate level of efficiency, remained most effective when co-administered with other antidotes. 4-dimethylaminophenol and amyl nitrite rated the lowest, with negative effects similar to sodium nitrite. Adrenaline was tested as an antidote in one study where two novel antidotes both demonstrated promising results. Conclusion Hydroxocobalamin had the highest success rate and its safety profile make it the most suitable pre-hospital drug treatment for acute cyanide poisoning.