Carbon Monoxide Flashcards
What are delayed symptoms that may be associated with carbon monoxide poisoning?
Secondary to an incompletely understood cascade of endovascular oxidative injury and inflammation
What patients are most at risk of long-term sequelae with CO poisoning?
Those who have accidental occupational/domestic exposure
What are high-risk features for CO poisoning to result in long-term sequelae?
Significant LOC/coma, persistent confusion, abnormal cerebellar examination, metabolic acidosis, AMI, age >55 years
How much higher is the affinity of CO for Hb than oxygen?
210 times
What is the half-life of COHb dependent on and what does it depend on?
Oxygen concentration - room air 240 minutes, 100% oxygen 90 mintues
Describe the symptoms patients with CO poisoning present with.
CNS: headache, dizziness, incoordination, ataxia, seizures, coma. CVS: tachy, hypertension, ischaemia, hypotension, AMI. Respiratory: non-cardiac APO. Metabolic: lactic acidosis, rhabdo, hyperglycaemia. Other: DIC, bullae, alopecia, sweat gland necrosis
What is the frequency of persistent neurological sequelae in CO-intoxication survivors at 1 month? At 12 months?
30% and 6-10%. Symptoms include: personality changes, poor concentration, dementia, psychosis, parkinsonism, ataxia, hearing loss
List the correlation between COHb levels and the clinical features expected.
<10: smoker background level, 10%: asymptomatic/headache, 20%: dizzy, nausea, throbbing headache, 30%: vertigo, ataxia, visual changes, 40%: confusion, coma, seizures, 50%: CVS/respi failure, seizures, death
What are manners by which CO can be more rapidly eliminated?
Normobaric oxygen: 100% or high-flow oxygen for at least 8 hours + until all symptoms have resolved. Pregnant women for 25 hours. Hyperbaric oxygen: indications/effectiveness are controversial
What is an important follow-up plan for patients exposed to significant CO poisoning?
Neuropsychiatric assessment in 1/12
