Hypoventilation

Question 1

obstructive sleep apnoea

Answer 1

upper airway obstruction as muscles relax during sleep
common in obese
reduced sleep, patients will be v tired during the day
spectrum of disease
normal–>snoring–>severe obstruction
morning headaches, due to CO2 retention overnight
often self waken every few minutes in reaction to hypoxia
will most often present with people who are falling asleep at work etc
note difference between fatigue and actually falling asleep
much worse during REM (dream) sleep as muscle relaxation is at its highest

treatment: is it worth treating everyone?
CPAP - people will only accept if they are symptomatic

Question 2

NIV vs CPAP

Answer 2

NIV is a ventilator
CPAP blows room air - it does not ventilate, there is no cycle between inspiration and expiration. it blows air down the airway to act like a splint and keep the airway open