Acute Poisoning - Carbon Monoxide & Alcohols

Carbon Monoxide

Children more susceptible - higher rate of intake

Ix
CarboxyHb
- higher in smokers, urban joggers
- not suitable for LEVEL of exposure, only to confirm exposure
- if not high still doesn't rule out CO poisoning
ECG - non-specific ischaemia
CXR - inhalation injury
CoHb/ABGs - metabolic acidosis, hypokalaemia, increased anion gap
Increased CK - from rhabdomyolysis

Tx
HbO
Hyperbaric oxygen

Alcohols
Ethanol
Methanol
Ethylene glycol
Isopropyl alcohol

Ix

Specific levels only useful is raised - not good indicator of outcome

Anion gap
- difference b/w plasma concentrations of cations and anions
- increased anion gap = increased presence of unmeasured anions 

eg alcohols/overproduction of organic acids/decreased excretion eg in renal failure

- can be used to monitor progress

[Na+ + K+] - [HCO3- + Cl-]

>20mmol/L = lactate, formate, oxalate

Osmolar gap

- difference b/w measured and calculated osmolality

- osmolar gap in metabolic acidosis = presence of unmeasure osmoles ie methanol, ethanol, ethylene glycol

2(Na+ + K+) + Urea + Glucose

Tx

Methylpyrazole
- inhibits alcohol dehydrogenase
- predictable elimination, no CNS depression

- expensive

Fatal dose of ethanol:
- Adults = 6-10ml/kg
- Children = 4ml/kg