Toxin-induced cardiac arrest: frequency, causative agents, management and hospital outcome.

Background: Cardiac arrest (CA) is a public health problem, with various etiologies and a fatal issue in 90-95% of cases. Toxin-induced cardiac arrests (TICA) are poorly described. Scarcity of national data prompted us to carry-out this study.

Aim: To determine TICA frequency in a Tunisian reference center in toxicology and its hospital prognosis, and to describe its clinical and therapeutic aspects Methods : Data were collected retrospectively over an 8-years period. We included patients admitted for post-CA care with highly suspected or confirmed TICA. Clinical and toxicological data were recorded.

Results: We recorded 21 cases of TICA, which represented 48.8% of CA. A single toxic agent was incriminated in 90% of cases. Main causative agents identified in our series were pesticides and betablockers: chloralosed (n = 6), carbamate inhibitor of cholinesterase (n = 5), acebutolol (n = 4) and organophosphate (n = 2). One case of opiates and cocaine poisoning was reported. Median duration of "no flow" was 0 minutes. Mean duration of "low flow" was 13.74±9.15 minutes. An initial shockable rhythm was noted only in three patients. Mortality rate was 76% (16/21). Four of the five survivors had a Cerebral Performance Category Scale (CPC) 1, only one patient survived with a CPC 3. Factors associated with mortality were : the duration of "low flow" (p=0.02) and APACHE II score (p=0.014). APACHE II≥29 was the only independent factor (OR=2.0, 95%CI [1.07;3.71]).

Conclusion: TICA were most frequently provoked by pesticides, mortality was high and was independently predicted by APACHE II score.