Obstructive Sleep Apnoea

Question 1

What is OSA?

Answer 1

A common sleep disorder characterised by recurrent episodes of partial or complete upper airway obstruction during sleep, leading to intermittent hypoxia and arousals from sleep.

Question 2

Predisposing factors for OSA?

Answer 2

1) Obesity
2) Age
3) Male
4) Menopause
5) FH
6) Alcohol & sedatives
7) Smoking

Question 3

Clinical features of OSA?

Answer 3

1) Excessive snoring

2) Periods of apnoea

3) Daytime sleepiness

4) Compensated respiratory acidosis

5) HTN

Question 4

How does OSA affect BP?

Answer 4

Can cause HTN

Question 5

How does OSA affect acid base balance?

Answer 5

Compensated respiratory acidosis

Question 6

What can be used for a formal assessment of sleepiness in OSA?

Answer 6

1) Epworth Sleepiness Scale (questionnaire completed by patient +/- partner)

2) Multiple Sleep Latency Test (MSLT)

Question 7

What does the Multiple Sleep Latency Test (MSLT) measure?

Answer 7

measures the time to fall asleep in a dark room (using EEG criteria)

Question 8

What investigation is used to diagnose OSA?

Answer 8

Sleep studies (polysomnography) e.g. EEG, respiratory airflow, thoraco-abdominal movement, snoring and pulse oximetry

Question 9

Mx of OSA?

Answer 9

1) Weight loss

2) CPAP (1st line)

3) Inform DVLA if OSA is causing excessive daytime sleepiness