OSA

Question 1

Definition of OSA

Answer 1

Characterized by recurrent episodes of partial or complete airway obstruction during sleep

Question 2

Pathophysiology

Answer 2

Not entirely understood - smaller upper airways and substantial decrements in pharyngeal dilator muscle activity during sleep
Recurrent arousals from sleep, hypoxemia and hypercapnia lead to sequelae

Question 3

Diagnosis

Answer 3

Polysomnogram (gold standard) - meassures respiratory events and hours of sleep - apnea-hypopnea index is derived (AHI)

• AHI > 5 per hour confirms OSA
• combination of AHI, dgree of sleepiness, and presence or absence of CV problems determines the severity of disease

Question 4

Additional testing

Answer 4

Reduced channel phlysomnography
Overnight oximetry
Serum TSH level
CBC
CXR
ECG
ABG

Question 5

Treatment

Answer 5

Weight loss of at least 10% in obese patients
Avoidance of alcohol and sedatives
Lateral sleeping position
Nasal obstruction/congestion tx - nasal corticosteroids, and decongestants
Mod/severe
- CPAP - pneumatically splints the airway preventing collapse, raises intraluminal airway pressure and inc. FRC
- BiPAP