T58 + (X47.99/X67.99/Y17.99)
DESCRIPTION
Poisoning caused by accidental or intentional exposure to fires in poorly ventilated areas, combustion engines, faulty stoves and faulty heating systems. Patients present with:
- dizziness
- impaired level of consciousness
- headache
- tachycardia
- seizures and other CNS symptoms
- cherry red skin and lips
- chest pain
- nausea and vomiting
- retinal haemorrhages
- metabolic acidosis (severe)
- respiratory alkalosis (mild)
- high arterial carboxyhaemoglobin levels
Note: There may be a normal arterial PaO2, but low oxygen saturation on pulse oximetry. Neither are useful in assessing severity of carbon monoxide poisoning. Ideally, a blood gas sample should be sent for co-oximetry to specifically detect carboxyhaemoglobin levels.
GENERAL MEASURES
Remove patient from toxic environment.
Ventilation may be needed in deeply comatose patients.
Monitor ECG and neurological status.
MEDICINE TREATMENT
- Oxygen, 100%, via positive pressure facemask.
For seizures: R56.8 + (T58/X47.99/X67.99/Y17.99)
Treat with benzodiazepines - see Status epilepticus .
Note: Phenytoin should be avoided (due to potential cardiotoxicity).
Metabolic acidosis:
Metabolic acidosis shifts the oxygen-dissociation curve to the right and therefore aids in maintaining tissue oxygenation despite reduced haemoglobin carrying capacity. Metabolic acidosis should only be treated if profound and persistent, following standard treatment protocols.
Patients should be followed up after discharge for the persistence of neurocognitive symptoms.