Sleep related breathing disorders Flashcards
Common misconceptions about sleep and facts?
Sleep is time for the body in general and the brain specifically to shut down for rest.: false Sleep is an active process involving specific cues for its regulation
Getting just one hour less sleep per night than needed will not have any effect on daytime functioning: falseWhen daily sleep time is less than an individual needs, a “sleep debt” develops.
The body adjusts quickly to different sleep schedules.
People need less sleep as they grow older.
A “good night’s sleep” can cure problems with excessive daytime sleepiness.
The body adjusts quickly to different sleep schedules- why is this false?
The Biological Clock that times and controls a person’s sleep/wake cycle will attempt to function according to a normal day/night schedule even when that person tries to change it.
Why is this false- People need less sleep as they grow older.?
Older people don’t need less sleep, but they often get less sleep. That’s because the ability to sleep for long periods of time and to get in the deep, restful stages of sleep decreases with age.
why is this false? A “good night’s sleep” can cure problems with excessive daytime sleepiness.
Excessive daytime sleepiness can be associated with a sleep disorder or other medical conditions. Extra sleep may not eliminate daytime sleepiness that may be due to such disorders
Sleep is a what process? is consists of what stages?
Sleep is a dynamic process.
Two basic stages or states:
a. Non-Rapid Eye Movement (NREM)
b. Rapid Eye Movement (REM)
What are the three stages of NREM sleep?
Stage 1: The beginning of sleep
Stage 2: Sleep is easily awakened
Stage 3 &4 : Deep sleep, slow-wave sleep, dreaming is more common, but not as common as in REM sleep. In this stage parasomnia most commonly occur
Stage 1: Very light sleep
Stage 2: Sleep spindles and K complexes
Stage 3 & Stage 4: Show increasingly more high voltage slow waves
Stage 4: It is extremely hard to be awakened by external stimuli
What is Rapid eye movement sleep?
- Characterized by burst of rapid eye movement
- Decreased skeletal muscle tone, almost complete paralysis in limb muscles
- Important muscles: the heart, diaphragm, eye muscles, and smooth muscles continue to function
- The episodes of REM sleep are longer as the night progresses
Explain the physiologic changes that happen during REM and NREM sleep?
Sleep activity areas in the brain?
Sleep is actively generated in specific brain regions.
Sleep patterns during peoples lives?
Sleep patterns change during an individual’s life.
What is the biological clock?
An internal biological clock regulates the timing of sleep in humans. Biological clocks are genetically programmed physiological systems that allow organisms to live in harmony with natural rhythms such as day/night cycles and the changing seasons.
What is melatonin?
Synthesized and released by the pineal gland influences circadian sleep-wake rhythms
Secretion greatest at night
Inhibited by light exposure
Dreams?
Although reports of dreaming are most frequent and vivid when an individual is aroused from REM sleep, dreams do occur at sleep onset and during NREM sleep as well.
Hypothesis for functions of sleep?
- Restoration and recovery of body systems
- Energy conservation
- Memory consolidation
- Protection from predation
- Brain development
- Discharge of emotions
Sleep loss? which groups?
Many adolescents are chronically sleep-deprived and hence at high risk of drowsy driving crashes. In one large study of fall-asleep crashes, over 50% occurred with a driver 25 years old or younger.
What is apnea?
Apnea: Cessation of thermal sensor airflow by ≥ 90% of baseline for more than 10 seconds.
What is hypopnea?
Hypopnea: A 50% or greater decrease in airflow or a less than 50% airflow associated with arousals.
When measuring sleep related disordered breathing what are the two criteria we can use to classify severity?
Apnea-Hypopnea Index (AHI) Number of apneas and hypopneas per hour of sleep: AHI 0-5: Normal AHI 5-15: Mild SDB AHI 15-30: Moderate SDB AHI > 30: Severe SDB
Or
Respiratory Disturbance Index (RDI) Number of apneas and number of hypopneas and respiratory effortrelated arousals per hour of sleep: RDI 0-5: Normal RDI 5-15: Mild RDI 15-30: Moderate RDI > 30: Severe
Explain Upper airway resistance syndrome?
- Repeated arousals secondary to increased upper airway resistance (“Crescendo snoring”)
- AHI/RDI is normal
- No significant oxygen desaturation episodes
Explain obstructive sleep apnea?
Patient continues to make respiratory efforts against an obstruction (typically a narrow or closure in the upper airways).
Events usually more prominent during REM sleep caused by associated hypotonia of upper airway musculature.
A=airway
B= Rib cage
C=Abdomen
What is central sleep apnea?
Patient makes no respiratory effort during the apnea.
Obstructive sleep apnea features?
Common and undiagnosed, with a prevalence of 5-10%.
Increases with age.
Characterized by repetitive narrowing or collapse of the pharyngeal airway during sleep that can produce severe disabilities
Epidemiology features of OSA?
Asymptomatic with abnormal study AHI ≥ 5
24% of men 65% of older men 9% of women 56% of older women
Appropriate clinical symptoms and AHI ≥ 10 Referred to as OSA Syndrome
3% to 7% of men 20% of older men 2% to 5% of women 15% of older women
Risk factors for OSA?
- Body habitus (BMI > 30 Kg/m2)
- Weight gain 10% → 32% increase in apneas and hypopneas
- Increased neck circumference
- Gender: male/female 2:1 risk increase in postmenopausal women
- Ethnicity: greater risk African-American, Hispanic, Asian
- Obstructive upper airway anatomy/craniofacial abnormalities
- Medical comorbidities: CHF, DM, Renal failure, CVA, Hypothyroidism
- Alcohol and sedative use
Clinical presentaiton of OSA?
- Excessive daytime sleepiness
- Waking up unrefreshed/tired after sleeping
- Complain of morning headaches
- Irritability/personality changes/depression
- Cognitive impairment
- Decreased libido
- Morning dry mouth
- Nocturia/enuresis may also be seen
History of OSA?
- Input of bed partner or roommate often helpful.
- Loud, disruptive snoring. Patient “wakes the dead.” • Witnessed apneas.
- Most sensitive question: “Have you ever been told that you stop breathing while you sleep?”
Physical exam of OSA?
- Obesity
- Increased neck circumference
- Large tonsils and adenoids
- Large uvula
- High arched palate
- Low soft palate
- Hypertension
- Lower extremity edema
- Craniofacial abnormalities – retrognathia,micrognathia
Diagnosis of sleep apnea? what is the sleep scale?
The diagnosis of sleep apnea requires measurement of the abnormal breathing pattern and associated abnormalities that define the syndrome.
- Polysomnography is the gold standard
- History and Physical exam alone often nondiagnostic > 50% of patients do not have daytime sleepiness
- Witnessed snoring and apneas high predictive value of 64% with witnessed apneas being the best
Pathophysiology of Oxidative stress disorders?
Oxidative stress disorders
Ischemia – Reperfusion
What are the cardiovascular effects?
•Systemic hypertension •Pulmonary hypertension •Congestive heart failure •Coronary artery disease •Nocturnal arrhythmias •Stroke •Atherosclerosis
how does obstructive might increase the risk of CV disease?
Non-CV effects of OSA?
- Sleepiness –Crashes
- Depression
- Insulin resistance/Type 2 DM
Treatment of OSA?
Approaches:
- Behavioral
- Medical:
PAP (Positive Airway Pressure), Oral appliance
• Surgical: Upper Airway surgery, Bariatric surgery – and adjunctive therapy There is no pharmacotherapy for OSA
how does PAP help with OSA?
maxillomandibular advancement procedure for OSA?
Geniohyoid advancement for treatment of Obstruction sleep apnea?
Central Sleep apnea?
- Patient makes no respiratory effort during apnea.
- Much less common than OSA.
- Occurs in between 5% and 10% of all patients who have sleep disordered breathing.
- Occurs most commonly during NREM sleep.
Features of central sleep apnea?
Historical findings include daytime sleepiness and witnessed apneas.
• Snoring not a prominent finding
• Patients may have any body habitus
risk factors for central sleep apnea?
- Congestive Heart failure
- Neurological disease
- Ascent to high altitudes
Central versus obstructive sleep apnea?
What is Obesity – Hypoventilation Syndrome (OHS) “Pickwickian Syndrome”?
- Syndrome of morbid obesity and chronic hypoventilation with daytime hypercapnia (PaCO2 > 45 mm Hg).
- OSA is present in majority of patients.
What are Cheyne-stokes respirations?
- Cyclic rise and fall in respiratory pattern with recurrent episodes of apnea.
- Most commonly seen with congestive heart failure, central neurologic disease, or administration of sedative agents; but may occur in normal patients.
Pateint suspected of OSAS must fulfill what criteria?
The patient suspected of OSAS must fulfill criteria A or B, plus criteria C.
A. Excessive daytime sleepiness that is not better explained by other factors.
B. Two or more of the following that are not better explained by other factors.
- Choking or gasping during sleep
- Recurrent awakenings from sleep
- Unrefreshing sleep
- Daytime fatigue
- Impaired concentration
C. Overnight monitoring demons trates five or more obstructive breathing events per hour during sleep.
Severity of sleep apnea based on what?
Sleep 22: 667, 1999
- Normal < 5 events/hr.
- Mild 5 to 15 events/hr.
- Moderate 15 – 30 events/hr.
- Severe > 30 events/hr.
