What are the different stages of sleep
- Autogensis
- Stage I
- Stage II
- Stage III
- REM
Describe autogenesis stage of sleep
- Short 30-35 seconds
- Before stage I
- Increased peripheral and core temp
- Relaxation of muscles
Stage I sleep is characterized how
replacement of alpha with theta waves
Describe Stage I sleep
- First stage of sleep
- Drowsiness/presleep
- Hypnic jerks
what is the predominant sleep stage
stage II (45% of sleep)
Stage II sleep is characterized by
K complexes which are associated with sleep spindles
Describe Stage II sleep
- no eye movement
- Easily wake
- Dreaming rare
Stage III sleep is also called
slow-wave sleep (SWS)
Stage III sleep is characterized by
delta waves
Describe Stage III sleep
- Dreaming is more common in this stage than other NREM stages
- Parasomnia is most common here
- Amount of time spent in SWS decreases with increases in age
Describe REM sleep
- Defined by
- Rapid eye movement
- Muscle atonia
- EEG desynchronization
- Brain activity similar to that during waking hours (paradoxical sleep)
- Lightest stage of sleep
- Normally occurs close to morning
- REM periods in the beginning of the night are shorter than at the end
Describe the effect each drug has on sleep
- Presleep alcohol
- Marijuana
- Benzons
- TCAs
- Presleep alcohol= REM supression early in ngiht
- Marijuana= SWS depression with chronic use
- Benzons= supress SWS
- TCAs and MAOIs= Supress REM
Snoring is (inspiratory/expiratory) noise
inspiratory
Describe the differences between benign and pathological snoring
Bengin
- Soft palate vibration
- No mechanical impingement to breathing
Pathological
- Pharyngeal narrowing
- Higher pitched noise
- Higher frequency
- Turbulent airflow
Increased snoring leads to increased risk of carotid_
atherosclerosis
Upper airway resistance syndrome is defined as
- Crescendo snoring
- Arousal with snoring –> sleep fragmentation
- No O2 desaturation
- Frequent RERAs (Respiratory effort related arousal
- Common in thin women menopausal
- Inspiration and expiration take the same amount of time
In normal breathing which takes longer inspiration or expiration
inspiration (3x)
what are the three different kinds of sleep apnea and describe them
- Obstructive= absence of airflow despite breathing effort
- Central apnea= absence of airflow due to lack of breathing effort
- Mixed- both
Sleep apnea signs and symptoms
- Snoring
- Excessive daytime sleepiness
- Awakening with gasps or choking
- Fragmented light sleep
- Poor memory
- Irritable
- Decreased sex drive
- Morning headaches
- GERD
Prevalence of sleep apnea is higher in (men/women)
men
Risk factors for OSA
- Obesity
- Snoring
- Witnessed apneas
- Neck circumference (male= >17 inches and women >15 inches)
- Large tongue (scalloping)
- HTN
- etc.
Presence of OSA is a predictor for what major CV event
MI
Define apnea and hypopnea
Apnea= cessation of breathing for at least 10 seconds
Hypopnea= At least a 30% reduction in airflow for 10 seconds at least 4% reduction in blood oxygen
What is the AHI
Apnea/hypopnea index (total number of apnea and hypopnea events her hr of sleep)
