This results in a left shift of the oxygen dissociation curve.
Normal levels of carboxyhaemoglobin are <3% in non-smokers or <10% in smokers.
In terms of carbon monoxide poisoning:
- 10-30% carboxyhaemoglobin = mild poisoning
- 30-60% = severe poisoning
Features of carbon monoxide poisoning are vague:
- 90% have a headache
- 50% nausea/vomiting
- 50% vertigo
- 30% confusion
Patients look pink
Severe CO poisoning can cause:
- fits
- coma
- cardiac arrrest/arrthymias
- pyrexia
- muscle necrosis
- acute renal failure
- increased reflexes and tone
Treatment is:
- 100% oxygen
- hyperbaric oxygen if LOC/pregnant/neuro signs - this decreases the half life from 4 hrs to around 22 minutes.
Next.... some pharmacology with acetylator status
