February 12, 2016 - Excessive Daytime Sleepiness Flashcards
Scheme for Daytime Sleepiness
Big categories of…
Inadequate total sleep time - insomnia / sleep restriction
Poor quality of sleep - sleep apnea
Medical or psychiatric causes
Intrinsic sleep disorders
Pathophysiology of Obstructive Sleep Apnea
Closure of the oropharynx results from an imbalance of the forces that normally keep the airway open.
The nasopharynx may close, the oropharynx may close, or the hypopharynx may close.
Polysomnography
Used to diagnose OSA. It records heartrate, oxygen saturation, breathing, as well as arousals from sleep.
An “event” is complete cessation of airflow for at least 10 seconds, followed by a microarousal from sleep. To grade the severity of sleep apnea, the number of events per hour are reported as the apnea-hypopnea index (AHI).
<5 is normal, 5-15 is mild, 15-30 is moderate, and >30 is severe.
STOP BANG
Used to screen patients for obstructive sleep apnea.
S - snoring
T - tired
O - observed apneas
P - blood pressure
B - BMI >35
A - age >50
N - neck circumference >40
G - gender = male
High-risk is yes to >3 questions
Obstructive Sleep Apnea vs. Sleep Apnea Syndrome
OSA - AHI > 5
SAS - AHI > 5 and symptoms
When to Treat OSA?
When patients have symptoms (SAS).
If mild, treatment will depend on severity of symptoms.
If moderate, patient will likely benefit from treatment.
If severe, treat, they are at increased cardiovascular risk.
Treatment of OSA
Behavioural - weight loss, avoidance of alcohol, smoking cessation, alteration of body position in sleep, addressing nasal congestion
Interventional - Nasal CPAP, oral appliance, uvulopalatopharyngoplasty.
CPAP
Continuous positive airway pressure.
A ventilator which applies mild air pressure on a continuous basis to keep the airways continuously open in a patient who is unable to breathe spontaneously on their own.
