U01.16.038 Sleep apnea

Sleep apnea is characterized by repeated cessation of breathing for more than 10 seconds during sleep, leading to disrupted sleep and daytime somnolence. Diagnosis is confirmed through a sleep study.

Key Complications

Nocturnal Hypoxia:
- Can lead to systemic and pulmonary hypertension.
- Risk of arrhythmias, including atrial fibrillation and flutter.
- Potential for sudden death.
Hypoxia Effects:
- Increased erythropoietin (EPO) release.
- Enhanced erythropoiesis (production of red blood cells).

Types of Sleep Apnea

Obstructive Sleep Apnea (OSA)

Mechanism: Respiratory effort against airway obstruction.
Daytime Oxygen Levels: Normal PaO2 during the day.
Associated Factors:
- Commonly linked to obesity.
- Symptoms include loud snoring and daytime sleepiness.
Causes:
- Excess parapharyngeal tissue in adults.
- Adenotonsillar hypertrophy in children.
Treatment Options:
- Weight loss.
- Continuous positive airway pressure (CPAP) therapy.
- Dental devices.

Central Sleep Apnea (CSA)

Mechanism: Impaired respiratory effort due to central nervous system (CNS) injury or toxicity.
Associated Conditions:
- Heart failure (HF).
- Opioid use.
- May present with Cheyne-Stokes respirations (oscillations between apnea and hyperpnea).
Key Considerations: Think of the “3 C’s”:
- Congestive Heart Failure
- CNS toxicity
- Cheyne-Stokes respirations
Treatment: Positive airway pressure therapy.

Obesity Hypoventilation Syndrome (OHS)

Definition: A condition in which obesity (BMI ≥ 30 kg/m²) leads to hypoventilation.
Oxygen and Carbon Dioxide Levels:
- Increased Paco2 (partial pressure of carbon dioxide) during waking hours (retention).
- Decreased PaO2 and increased Paco2 during sleep.
Alternate Name: Also known as Pickwickian syndrome.

Points to Remember

Sleep apnea significantly impacts the quality of life and can lead to serious health complications.
Diagnosis through sleep studies is essential for effective management.
Treatment varies depending on the type of sleep apnea.

Tables

Type of Sleep Apnea	Characteristics	Treatment Options
Obstructive Sleep Apnea	Airway obstruction, loud snoring, daytime sleepiness	Weight loss, CPAP, dental devices
Central Sleep Apnea	Impaired CNS respiratory effort, Cheyne-Stokes	Positive airway pressure
Obesity Hypoventilation	Hypoventilation, obesity	Weight management, CPAP

Sleep apnea

Bibliography

Epstein, L. J., & Collop, N. A. (2016). Clinical Guidelines for the Evaluation, Management, and Long-term Care of Obstructive Sleep Apnea in Adults. Journal of Clinical Sleep Medicine, 12(2), 245-268.
Patil, S. P., & Hams, E. (2015). Obstructive Sleep Apnea: A Review of Current Management Strategies. American Journal of Respiratory and Critical Care Medicine, 192(5), 547-554.
Redline, S., & Tishler, P. V. (2015). The Epidemiology of Sleep Apnea: A Review. Sleep Medicine Reviews, 19(3), 145-155.

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