EXAM #2: SLEEP RELATED BREATHING DISORDERS Flashcards
How long is the sleep cycle?
90-110 minutes
What are the two major stages of sleep?
1) Non-REM (1-4)
2) REM*
*Note that there is no muscle tone during REM sleep
What happens to TV during sleep? Specifically, what happens during REM and NREM sleep?
Generally, TV goes down
Specifically,
- NREM= 6-16% decrease
- REM= 25% decrease
What happens to airway resistance during sleep?
Resistance INCREASES by 230%
What is Obstructive Sleep Apnea (OSA)?
Dynamic airway narrowing or closure during sleep that is terminated by arousal
What causes OSA?
1) Decreased muscular tone
2) Crowding of the upper airway
What are the sx. of OSA?
1) Loud snoring*
2) Oxygen desaturation
3) Frequent arousal
*Note that this is inspiratory and expiratory
What are the risk factors for OSA?
1) Obesity (increased soft tissue)
2) Family hx.
3) Treatment resistant HTN
4) CHF, a-fib, CVA
5) DM-II
What are the two major screening tools for OSA?
1) Berlin questionnaire
2) STOP-BANG screening test
Is OSA more common in males or females?
Males
What is the most common cause of OSA in kids?
Adenotonsillar hypertrophy
*Note that many of these kids will have learning difficulties b/c of their sleep apnea
What is the Epworth Sleepiness Scale?
This is a measure to quantify sleepiness
What neck size puts a patient at risk for OSA?
Men= greater than 17'' Women= greater than 16''
What Mallampati score is associated with an increased risk of OSA?
3 and 4
What is the gold standard to confirm the diagnosis of OSA?
Polysomnography
What does AHI stand for?
Apnea Hypopnea Index
*This determines the severity of OSA by recording the number of events per hour
What kind of patient qualifies for an in-home sleep study?
Uncomplicated case with no comorbidities
What are the general recommendations for treatment in OSA?
1) Weight loss
2) Exercise
3) Lateral body position
4) Smoking cessation
5) Avoidance of sedatives
What is the treatment of choice for OSA?
CPAP
What is central sleep apnea?
Recurrent cessation of respiration without associated ventilatory effort
What type of ventilatory pattern is seen in CSA?
Cheyne Stokes
What conditions are associated with CSA?
- CHF
- CVA
- Renal insufficiency
What causes CSA?
- High response to PaCO2 causing hyperpnea
- Subsequent decrease in PaCO2 causes insufficient stimulation of chemo response and apnea
How is OSA differentiated from CSA on sleep study?
OSA= movement of diaphragm and abdominal muscles
CSA= no movement of muscles
