Sleep Apnea (12/12/16) - Scharf

Question 1

OSA Pathophysiology

Cause and Result

Answer 1

• Cause: intermittent collapse of upper airway during sleep
  
  • Collapse → disruption of air flow
• Result:
  
  • Oxygen desaturations
  • Sleep fragmentation
  • Poor quality sleep

Question 2

Risk Factors for OSA

Answer 2

• Obesity***
• Increased neck size
• Age
• Male gender
• Race
• Anatomic factors
  
  • Retrognathia (where chin is v recessed)
  • Oropharyngeal crowding
  • Craniofacial abnormalities

Question 3

OSA Clinical Presentation (5)

Answer 3

• Loud snoring***
• Witnessed apneas
• Dry mouth in the morning
• Headache in the morning
• Excessive daytime somnolence

Question 4

OSA Physical Exam Findings

Answer 4

• Crowded upper airway
  
  • Macroglossia (big tongue)
  • Narrowing of lateral airway
  • High, arched palate
  • Retrognathia
  • Tonsillar hypertrophy (very very common in children)
• Obesity (BMI>30)
• Increased neck size
• Sleepy

Question 5

How is OSA diagnosed? (3)

Answer 5

• Polysomnogram - “sleep study”
  
  • Gold standard
  • Overnight in sleep lab
  • Comprehensive - assesses sleep staging, respiration, movements
• Home sleep test
  
  • Inexpensive
  • Patient gets to sleep at home
  • Not as comprehensive as polysomnogram
• Validated questionnaires
  
  • Extensively used in research

Question 6

How is OSA diagnosed on a polysomnogram

Answer 6

Apnea = cessation of flow for > 10 sec

• Obstructive apnea = presence of respiratory effect
• Central apnea = absence of respiratory effort
• Hypopnea = decrease in flow by > 30% for > 10 sec
  
  • Associated w oxygen desaturation or electrophysiological arousal

Calculate:

• Apnea-hypopnea index = # of apneas and hypopneas per hour
  
  • Mild = 5- <15 events per hour
  • Moderate = 15- <30 events per hour
  • Severe = >30 events per hour

Question 7

OSA Causes Sleep Fragmentation

Answer 7

Even if total sleep time is the same, the quality of the sleep declines (slow wave sleep and REM sleep decrease).

Question 8

OSA episodes increase sympathetic nerve activity.

Answer 8

• Norepi levels increased in arterial and venous supply in patients with OSA

Question 9

OSA Treatment (7)

Answer 9

• Weight loss (bariatric surgery)
• Adenotonsillectomy (children)
• Positional therapy
• Mandibular advancement device
  
  • Looks like a mouth guard: Move mandible forward to open airway
• Oral Pressure Therapy (WinX)
  
  • Negative pressure: pulls tongue forward to prevent it from falling back
• Hypoglossal Nerve Stimulator (Inspire)
• Continuous Positive Airway Pressure (CPAP)
  
  • ​Air comes in and opens airway
  • Nearly 100% effective when used

Question 10

Consequences of untreated OSA

Answer 10

• Symptomatic sleepiness
• Adverse health effects
  
  • Diabetes, HTN, heart disease, stroke, afib
  • Increased mortality