Chronic - Obstructive sleep apnoea

Question 1

Name 3 risk factors for OSA.

Answer 1

obesity

macroglossia: acromegaly, hypothyroidism, amyloidosis

large tonsils

Marfan’s syndrome

Question 2

How does OSA present?

Answer 2

Daytime somnolence due to waking up from sleep

Partner complaining of snoring or apnoea attacks

Hypertension (with every arousal there is a rise in BP)

Nocturia

Reduced libido

Question 3

What would be the acid base status of someone with OSA?

Answer 3

Compensated respiratory acidosis

Question 4

How can you assess sleepiness in OSA?

Answer 4

Epworth Sleepiness Scale - questionnaire completed by patient +/- partner

Multiple Sleep Latency Test (MSLT) - measures the time to fall asleep in a dark room (using EEG criteria)

Question 5

What is the diagnostic test for OSA?

Answer 5

sleep studies (polysomnography) - ranging from monitoring of pulse oximetry at night to full polysomnography where a wide variety of physiological factors are measured including EEG, respiratory airflow, thoraco-abdominal movement, snoring and pulse oximetry

Question 6

How is OSA managed?

Answer 6

• weight loss
• continuous positive airway pressure (CPAP) is first line for moderate or severe OSAHS
• intra-oral devices (e.g. mandibular advancement) may be used if CPAP is not tolerated or for patients with mild OSAHS where there is no daytime sleepiness
• the DVLA should be informed if OSAHS is causing excessive daytime sleepiness
• limited evidence to support use of pharmacological agents