Wierd and wonderful respiratory

Question 1

Briefly outline the pathophysiology of CO poisoning

Answer 1

• impaired OR delivery + utilisation + ROS
  > CO has a higher affinity for heme&raquo_space; allosteric change of molecule causing difficulty to offload O2 molecule
  > left ward shift of O2 disassociation curve, compounds the impairment in tissue delivery

Question 2

What are the signs of severe toxicity in CO poisoning?

Answer 2

neurological signs - seizures, syncope, LOC
lactic acidosis
AMI, arrithmiyas, pulmonary oedema

Question 3

What body system is affected long-term after CO poisoning?

Answer 3

delayed neuropsychiatric syndrome - variable manifestations (cognitive deficits, personality changes, movement disorders). Usually manifests 20 days post CO poisoning
- NOT based on CO levels, but rather symptoms of LOC at the time of the acute event

Question 4

True or false: CO levels correlate with the degree of poisoning

Answer 4

False!

Question 5

Why is standard pulse oximetry not useful in CO poisoning?

Answer 5

It does not differentiate between COhb from oxyhaemoglobin

Question 6

Outline the management algorithm for CO poisoning

Answer 6

• hiflow oxygen (1st line)
• if related to smoke inhalation > hydrocobalamin (to treat possible cyanide toxicity)
• severe - hyperbaric oxygen therapy