Sleep Apnea Flashcards
What stages of sleep should you know?
WAKE, NONREM (N1, N2, N3), REM
What sleep stage is “deep sleep”? It is difficult to wake a person from this stage.
N3
When does most N3 sleep occur?
the first 1/3 of the night
When does most of REM sleep occur?
early morning
The worst breathing abnormalities occur in __________ sleep stage.
REM
NonREM sleep accounts for ______% total sleep time?
80%
There’s one thing you should remember about what happens during NREM sleep?
Growth hormone secretion (specifically during N3)
REM sleep acocunts for ________% total sleep time.
20%
What is happening to you during REM sleep?
skeletal muscle hypotonia, dreaming
Sleep that includes abnormal sleep behavior is called__________
parasomnia
The PSG (polysomnograph) sleep test includes all kinds of stuff. What all is it measuring (7)
EEG (shows sleep stages, arousals), EKG, airflow, chest band (abdominal effort), pulse ox, LE EMG (leg movements–low extremity electromyogram), video (parasomnia)
What types of PSG’s can be ordered? (4)
1) Diagnostic PSG (does patient have sleep apnea? What kind?)
2) positive pressure titration PSG (determines how much pressure needed for CPAP)
3) split PSG (diagnose for half the night and do pressure titration 2nd half)
4) Home sleep test (covered by insurance, determines number of apneas/hypopneas per hour and records desats)
The PSG for your patient shows that they have periods of time where there is NO airflow despite a continuous respiratory effort. What type of sleep apnea is this?
Obstructive
What is the term for either shallow breathing or a low respiratory rate?
hypopnea
The PSG for your patient shows that they have periods of time where their airflow is markedly reduced despite a continuous respiratory effort. What type of sleep apnea is this?
Obstructive hypopnea
You don’t need a PSG to notice your ICU patient has a breathing pattern that seems to get shallow and fast for periods of time, sometimes you think she might not be breathing at all. What type of breathing is this?
Cheyne-stokes breathing
Cheyne-stokes breathing is common in what disease?
CHF
You order a PSG and see that your patient has a crescendo-decrescendo breathing pattern between central apneas. There is a problem with the respiratory effort that seems to be causing this problem. What type of sleep apnea is this?
central apnea
You order a PSG and see that your patient has an irregular breathing pattern. Irregular airflow corresponds to irregular respiratory effort. What type of sleep apnea is this? Who is at high risk for this apnea?
Crap, this type is not labeled…uhh, sorry. But it is common in patients on potent narcotics. I’m thinking it is ataxic breathing? (Oh! per Ryan, this one’s not in the book)
FUN FACT
Oh man! This PSG is all over the place. You see periods of absent airflow, some cheyne-stokes breathing, some periods of minimal respiratory effort, all kinds of atypical crap. What type of sleep apnea is this for god’s sake?
Mixed apnea
What is the apnea + hypopnea index (AHI)
the AHI is the # apneas + # hypopneas divided by total SLEEP time (hrs).
What AHI score indicates a mild apnea? Moderate? Severe?
mild 30
What are other big factors (besides the AHI score) in determining the severity of sleep apnea?
Oxygen desaturation, symptoms (“treat the patient, not the AHI score”)
Deep, gasping inspiration with a pause at full inspiration…followed by a brief and insufficient release. (damage to pons or medulla from stroke or trauma)
apneustic respiration
If your patient has apneustic respiration, what clinical signs and symptoms would you expect to see?
decerebrate posturing, fixed dilated pupils, coma/stupor, paralysis, absent reflexes
What drugs could cause apneustic respirations?
Ketamine
There’s this nifty classification that is part of your physical exam to determine how likely sleep apnea is based on a patient’s anatomy. (meaning, do they have a thick posterior tongue?) What is this called?
Mallampati Classification.
The _________ your Mallampati score, the MORE likely you are to get sleep apnea.
higher (scale is from 1-4)
What is the most accurate indicator that your patient will test positive for sleep apnea?
bedpartner report of heavy snoring and/or apneic events
What are the 4 clinical clues you should use to screen for sleep apnea?
1) loud snoring
2) Observation of apnea/gasping by bedmate
3) Presence of htn ( especially in am)
4) Large neck circumference (women>15” and men>17”)
What are other common symptoms of sleep apnea patients, that are not always present?
daytime sleepiness (about 50%), headache in the AM, grogginess, high Mallampati (4), short neck, small back-set jaw
What makes OSA markedly worse?
ETOH
What physiological reactions is your body having as a result of sleep apnea?
increased nocturnal BP, increased HR, increased sympathetic tone
What types of problems can manifest in undiagnosed OSA?
1) sleepiness
2) Social consequences (your spouse leaves you)
3) Respiratory failure (rut-roe)
4) Cor pulmonale
5) Arrhythmia
What is the pathophysiology of OSA?
1) decrease in the area of the pharynx
2) collapse of airway
3) gravity pulls tongue into pharynx
4) REM sleep causes hypotonia of throat muscles
What are treatments of OSA?
PAP (CPAP, biPAP), oral appliances, upper airway surgery, wt loss, positional devices
How do you determine who gets what treatment?
discuss options with patient, weigh costs, benefits. Remember surgery may only improve apnea by 50% Oral appliances are expensive. PAP is most commonly used. Severe OSA may use all of these treaments. All overweight patients should be counseled in WT LOSS. (although that may not always improve apnea)
What’s the difference in CPAP and BiPAP? Why would you use one over the other?
CPAP is a continuous pressure all the time. BiPAP uses high pressure during inspiration and low pressure during expiration. BiPAP has a feature that will “fire” if you don’t breath. There is no difference in effectiveness. Choose which option is most affordable/comfortable for patient. (APAP is auto adjusting)
What medications can help improve daytime sleepiness?
Provigil, Nuvigil
How is treatment of sleep apnea in CHF patients?
Aside from treating underlying dz, its not much different. Do PAP and Nocturnal oxygen
