Seen with organophosphorus toxicity and also with treatment for myasthenia
About
- Overstimulation of central and peripheral acetylcholine based nicotinic acid receptors
- Both at the neuromuscular junction and at muscarinic receptors due to excess ACh
Aetiology
- May be due to reduced breakdown of acetylcholine by acetylcholinesterase
- Seen with sarin type nerve gas agents and organophosphate poisoning and carbamate pesticides
- Patients taking excess of their medications for myasthenia or dementia.
Clinical
- Nausea, vomiting, diarrhoea, excessive salivation and sweating
- Bronchial secretions, miosis, bradycardia or tachycardia, cardiospasm
- Flaccid paralysis, respiratory failure, increased sweating, hypertension
- Copious salivation, bradycardia, copious bronchial secretions along with miosis.
- Death from cardiac arrest or respiratory paralysis and pulmonary oedema.
Investigations
- FBC, U&E, ABG, Lactate, CXR, ECG
Management
- If OP poisoning ensure no contamination of OP from skin to skin spread to staff
- ABCs, Oxygen high flow as needed. Tracheostomy
- Bronchial aspiration and postural drainage may be required. Cardiac monitor.
- Cholinergic crisis treated with antimuscarinic drugs like IV Atropine 1-4 mg and pralidoxime.
- Additional doses of Atropine may be given every 5 - 30 minutes as needed to control muscarinic symptoms.
- Atropine overdosage should be avoided as tenacious secretions and bronchial plugs may result.
- Intubation and ventilation if not improving.