2.23 - Cardiorespiratory Problems With Sleep

Question 1

What is obstructive sleep apnoea and what does it result in?

Answer 1

OSA –> repetitive episodes of upper airway obstruction during sleep which cause a reduction in airflow –> episodes lead to hypoxia and hypercapnea and precipitate arousal from sleep.
It can lead to systemic HT and mild pulm. HT, coronary artery disease, arrhythmias and stroke.

Question 2

What is the difference between apnoea and hypo apnoea?

Answer 2

Apnea = cessation of flow ≥ 10secs
Hypoapnea = ↓ airflow ≥ 10secs with associated arousal and Hb desaturation

Question 3

What is central apnoea and what condition is it commonly associated with?

Answer 3

Instability of the central ventilator control system during sleep, occurring commonly at sleep onset. Commonly seen in congestive heart failure as Cheyne-stokes type respirations, opiod/respiratory depressant use, acromegaly, hypothyroidism and renal failure.

Question 4

What are the consequences and symptoms of OSA?

Answer 4

Poorly refreshing sleep, excessive daytime sleepiness, problems with memory and concentration, poor job performance, depression, family discord, decreased quality of life, increased MVA

Question 5

What are the cardiovascular consequences of OSA?

Answer 5

Systemic HT, myocardial ischaemia, cardiac arrhythmias, cerebrovascular disease, pulmonary HT/cor pulmonale with obesity hypoventilation.

Question 6

How can OSA be managed?

Answer 6

Weight reduction
Avoidance of tobacco and alcohol
CPAP via a nasal mask during sleep is effective and recommended for those with moderate to severe disease
Surgery to relieve phayngeal obstruction (tonsillectomy, tracheostomy) is occasionally needed.