Abstract
This retrospective chart review focused on a Korean population of out-of-hospital cardiac arrests (OHCA) in order to define epidemiologic factors related to outcome when poisoning was the causative factor. Data were collected from a registry of OHCA recorded by the Korean EMS system between 2006 and 2008. Available demographics included initial rhythm, presence of bystander CPR, witness involvement, treatments rendered by EMS, response time, and pre-hospital time. Poisoning cases were determined by physician report, history from witnesses or EMTs, or clinical symptoms. Poisons were classified into pesticides (insecticides, herbicides, or other), nonpesticides, and unknown.
The authors used survival to hospital and survival to discharge as outcome measures. A total of 52 467 EMS charts were available, and poison-induced OHCA with CPR was identified in 714 of these patients. In poison-induced OHCA, 13.7% survived to the hospital and 3.6% survived to discharge, compared with 14.5% and 3.9%, respectively, for OHCAs from other causes. Causes of OHCA in the poisoning group included insecticide 15.5%, herbicide 13.2%, unknown pesticide 20%, nonpesticide 16.8%, and unknown poison 34.6%. The best outcomes were observed in insecticides, with a survival to hospital of 22.5% and survival to discharge of 10%. As a subgroup, carbamates survived to hospital in 30% and survived to discharge in 18%. Whereas, in the case of herbicides, survival to hospital was 3% and survival to discharge was 0%.
The authors suggest that the better survival observed in some insecticides are a result of easier recognition through smell and available antidotes. Limitations of this study included a population specific to the Korean EMS system and difficulty categorizing cases inherent in a retrospective chart review.
(Resuscitation. 2011 [Epub ahead of print]) JH Park, SD Shin, KJ Song, et al.
Prepared By Anil Menon, MD, UTMB/NASA Aerospace Medicine Fellow, Galveston, Tx, USA