23. Sleep-Disordered Breathing Flashcards
what are the 3 neural stages?
wake, NREM, REM
sleep spindles and K complexes are characteristic of which stage of sleep?
stage 2
NREM is divided into 3 stages; what are they?
N1, N2, N3
what is stage N3 known as?
slow wave/deep sleep
REM is known as what?
Stage R
what occurs in REM
dreaming, skeletal muscles are paralyzed (to prevent acting out dreams), rapid eye movmeent
How long are typical REm cycles?
90 min. they grow longer in second half of the night.
main stimulus driving resp is what?
PC02
how is hypercapnia detected?
via medullary chemoreceptors as well as carotid body chemoreceptors
what occurs when we are in NREM sleep? what controls breathing?
no longer partly behavioral; purely metabolic.
what happens to the PC02 set point in sleep?
is is raised slightly, resultin gin mild hypoventilation.
what happens during REM with resp?
more reapid, more variable. may be due to behavioral inf related to dream content.
what happens with blood gas abnormalities during sleep?
they are made worse.
def of apnea?
complete cessation of airflow. can either be central or obstructive in origin.
what is OSA/what causes it?
obstructive sleep apnea/dynamic obstruction of upper airway, usually during inspiration.
what is the main stimulus for arousal with OSA?
likely the inc resp efforts
treatment options: conservative
wt loss, avoiding EtOH, dental appliances.
tx options: more severe
surgery, CPAP
what is CSA?
central sleep apnea, due to decr in drive to breathe.
what are most common types of CSA
cheyne-stokes (associated with congestive heart failure) and usu of opioid meds
what are the cardiovascular consequences for a person with OSA?
sig higher risk for CV disease. more likely to dev systemic HTN, also stroke, ischemia, CHF. link is probably systemic inflammation (associated with both OSA and CHF).
what is the connection between hypoxemia and pulm HTN?
hypoxemia is a vasoconstrictor in the pulm system!!! so lack of 02 can lead to pulm HTN.
