SLEEP APNEA Flashcards
Intermittent cessation of airflow at the nose and mouth for > 10 seconds during sleep.
Sleep apnea
- clinical disorder that arises from recurrent apneas during sleep
- Obstructive sleep apnea/hypopnea syndrome (OSAHS) caused by occlusion of the airway
Sleep apnea syndrome
- caused by absence of respiratory effort
- Mixed sleep apnea: a combination of OSAHS and CSA
Central sleep apnea (CSA)
Prevalence of Sleep Apnea
- 2% of middle-aged women and
* 4% of middle-aged men
Sex Prevalence is twice as high in men as in women.
- Typical patient Male, 30-60 years of age
* Women with OSA are typically postmenopausal
OSAHS Risk Factors
- Obesity In Western populations,
- ~50% of patients have a body mass index (BMI) >30 kg/m2
- Alcohol use
- Structural reduction in airway size
- Shortening of the mandible and/or maxilla (Mandibular retrognathia and micrognathia)
- Endocrine: Hypothyroidism and acromegaly
- Male sex Middle age (40-65 years)
- Smoking & Nasal congestion (possibly)
- Myotonic dystrophy, Ehlers-Danlos syndrome, Down syndrome, Treacher-Collins syndrome
Major causes of OSAHS
- Decreased upper-airway muscle tone
* Decreased upper-airway lumen size
Major causes of CSA
- Defects in the metabolic respiratory control system and/or respiratory neuromuscular apparatus (hypercapnic CSA)
- Primary and secondary central alveolar hypoventilation (Ondine’s curse) syndromes
- Respiratory muscle weakness
SYMPTOMS & SIGNS OSAHS
- Snoring
- Excessive daytime sleepiness
- Sleep attacks
* Result in inability to work effectively
* Damage interpersonal relationships
* Disturbed sleep and unrefreshing nocturnal sleep - Witnessed apneas during sleep
- Depression
- Difficulty concentrating
- Decreased libido
SYMPTOMS & SIGNS CSA
- Poor sleep
- Sleep maintenance insomnia
- Morning headache
- Daytime fatigue and sleepiness
Evidence of:
• Pulmonary hypertension
• Recurrent respiratory failure
• Right-sided heart failure
CSA can be identified with certainty only if either esophageal pressure or respiratory muscle electromyography is recorded and shown to be absent during the events.
A useful guideline for patients with troublesome sleepiness includes those with an ____ >11,and those for whom
sleepiness during work or driving poses problems.
Epworth Sleepiness Score
detailed overnight sleep study that includes recording of:
• Electrographic variables (electroencephalogram, electro-oculogram, and submental electromyogram)
• Ventilatory variables to identify apneas and classify as CSA or OSA
• Arterial oxygen saturation
• Heart rate
• Key finding: episodes of airflow cessation despite evidence of continuing respiratory effort
• Severe OSA: >30 obstructive events and arousals per hour of sleep (or significant daytime sleepiness)
Polysomnography Diagnnosis of OSAHS
• Polysomnography
- Key finding: recurrent apnea not accompanied by respiratory effort
• Measurements of transcutaneous PCO2, which reflect arterial PCO2
- Patients with a defect in respiratory control or neuromuscular function typically demonstrate an elevated PCO2 that tends to increase progressively during the night.
- Patients with instabilities in respiratory control system typically demonstrate a mild degree of hypocapnia.
• Respiratory muscle electromyography: Absent effort with events
DIAGNOSING CSA
TREATMENT APPROACH
DETERMINE WHETHER PATIENT HAS OSAHS OR CSA (EPWORTH SCORE) -> MANAGE OSAHS ACCORDING
TO SEVERITY + Manage CSA by treating the underlying condition.
TREATMENT OF OSAHS
- Prevents upper-airway occlusion by mechanical splinting of the pharyngeal airway with positive pressure maintains airway patency
• Treatment of choice in severe OSA
• Superior to more conservative therapy in mild to moderate disease
• Well tolerated and effective in > 80% of patients who have received proper training
• Improves sleep quality, reduces daytime sleepiness and driving accidents, and decreases nocturnal hypertension
Nasal continuous positive airway pressure (CPAP)
TREATMENT OPTION: LIFESTYLE INTERVENTIONS
- Weight reduction
- Bariatric surgery
- 85% of morbidly obese patients who undergo bariatric surgery have resolution or significant amelioration of OSA.
- Consider as treatment in severely obese patients with refractory OSA.
- Alcohol avoidance
- Smoking cessation
- Avoidance of sleeping in the supine posture
TREATMENT OPTION: MPS
• modifies the position of the mandible and tongue
• Shown in RCTs to improve OSAHS patients’ breathing during sleep, daytime somnolence, and blood pressure
• Considered second-line treatment for patients who cannot tolerate CPAP
• In RCTs comparing it with CPAP, outcomes and compliance were better with CPAP.
Mandibular repositioning splint (MRS)
TREATMENT OPTION: SURGERY
• effective in those with retrognathia (posterior displacement of the mandible).
• Should be considered particularly in young and thin patients
Jaw advancement surgery-particularly maxillomandibular osteotomy
TREATMENT OPTION: SURGERY
curative but rarely used because of the associated morbidity
Tracheostomy:
TREATMENT OPTION: SURGERY
can be curative in the morbidly obese
Bariatric surgery
TREATMENT OPTION: SURGERY
can be highly effective in children but rarely in adults
Tonsillectomy
Recommended for patients who experience residual sleepiness despite optimal CPAP therapy, provided CPAP compliance is closely monitored
Modafiniland armodafinil
- Nasal CPAP therapy Goal is __ 4.5 hours of CPAP use per night.
- Maximal improvement may take as long as ___ months.
- Follow-up visits should be scheduled within ___ months after initiation of CPAP treatment and at least yearly thereafter.
- Look for ___ improvement, CPAP compliance, and equipment maintenance.
- Repeated ___ is reserved for patients without symptom relief.
- >
- 2
- 2
- symptomatic
- polysomnography
