Coma describes an altered mental status where the patient cannot be roused. It is a common manifestation of acute poisoning by many agents
In a potentially poisoned patient, coma may be the result of:
- Direct toxic effect on the CNS: Wakefulness and consciousness depend on complex mechanisms involving many pathways and neurotransmitter systems.
- Secondary effect of poisoning on CNS: Hypoxaemia, hypoglycaemia, hyponatraemia, hypotension, seizures or cerebral oedema
- Alternative non-toxicological diagnoses: Metabolic encephalopathy, neurotrauma, space occupying lesion or meningoencephalitis.
References
- Daly FFS, Little M, Murray L. A risk assessment approach to the management of acute poisoning. Emergency Medicine Journal 2006; 23:396-399.
- International Liaison Committee on Resuscitation, 2005 American Heart Association Guidelines for Cardiopulmonary and Emergency Cardiovascular Care- Part 10.2: Toxicology in ECC. Circulation 2005; 112(24 Supplement I): IV126-IV132.
- Isbister GK, Downes F, Sibbritt D et al. Aspiration pneumonitis in an overdose population: Frequency, predictors and outcomes. Critical Care Medicine 2004; 32:88-93.
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