Where does it come from?

• Burned carbon without enough oxygen to create carbon dioxide
• Burning fuel (charcoal, wood, natural gas) with inadequate ventilation (think burning things for heat in small place)       

What does it do?

• Binds Fe on Hb with 250x affinity than O2
• Decreases ability of Hb to offload oxygen
• Decreased carrying capacity + decreased offloading = decreased O2 to tissues
• Other effects:
• Inhibits proteins within electro transport chain  decouples oxidative phosphorylation  decreased ATP + free radicals
• Half life longer than CO bound to Hb
• Lipid peroxidation and Inflammation in brain with ultimate neuronal cell death
• Continues after initial stabilization
• Thought to be caused of delayed neurological sequale
• Cardiac injury and dysfunction
• CO similar to NO  vasodilation
• Global hypokinesis
• Arrythmias
• Greatest effects on brain and cardiovascular system

 Clinical: Variable

• Headache most common
• Dull, frontal, constant
• “Flu-like” malaise, nausea, vomiting, dizziness
• Often misdiagnosed as viral illness especially because peak time for space heaters is winter
• Neurological
• Confusion, ataxia, focal deficit, seizure, LOC, coma
• Cardiovascular/ Respiratory 
• CP, SOB, Hypotension, tachycardia, tachypnea, arrythmias, EKG changes
• Pulse ox NOT reliable: machine detects COHb same as Hb with O2
• Will be normal despite profound hypoxia at tissue level

 Treatment & Management

• ABC’s
• Remove source and Oxygen
• Oxygen competitively inhibits CO and displaces from Hb
• Half-Life of COHb on RA: 250-320 mins, NRB: 90 minutes
• Hyperbarics
• Half-life: 30 minutes
• Best if done early (less than 6 hours)
• Indications:
• Carboxyhemoglobin >25%
• Carboxyhemoglobin >20% and pregnant (? 15%)
• LOC, seizure
• Severe metabolic acidosis (pH <7.1)
• Evidence of end organ ischemia (chest pain, EKG changes, AMS)
• Greatest effects on CV, brain: if these affected  transfer