Week 7: Hypoventilation, Sleep apnoea

Question 1

4 Causes of hypoventilation

Answer 1

1. Sleep apnoea
2. Respiratory muscle weakness
3. Reduced thoracic cage compliance
4. Reduce central drive

Question 2

4 symptoms of hypercapnia

Answer 2

1. Sleepy
2. Poor concentration, altered GCS
3. Early morning headache
4. Flapping tremor

Question 3

Why do you get early morning headaches with hypercapnia

Answer 3

Vasodilation of cerebral vessels (like raised ICP)

Question 4

Pathophysiology of Obstructive Sleep Apnoea

Answer 4

Excessive narrowing of upper airways during REM sleep

Question 5

Endocrine conditions which can predispose to Obstructive Sleep Apnoea

Answer 5

1. Acromegaly

2. Hypothyroidism

Question 6

Symptoms of Obstructive Sleep Apnoea

Answer 6

1. Snoring
2. Waking frequently
3. Breath holding
4. Resuscitative grunt
5. Waking up unrefreshed

Question 7

Investigations for Obstructive Sleep Apnoea

Answer 7

1. Overnight oximetry (can diagnose most cases)
2. Polysomnography (sleep study)
3. Epworth sleepiness scale