L9 - Sleep Disordered Breathing

Question 1

Apnoea

Answer 1

Absence of respiration for 10 seconds

Question 2

Sleep Apnoea

Answer 2

Excessive daytime sleepiness with more than 5 apnoeic periods per hour during sleep.

Question 3

Snoring

Answer 3

Recurrent narrowing of the supraglottic airway during sleep

Question 4

Patency of upper airway dependes on…

Answer 4

1. Pharyngeal dilator muscle contraction (genioglossus)

2. Negative pressure of inspiration

Question 5

Clinical features of sleep apnoea

Answer 5

• Poor concentration, night time choking, reduced libido, drowsiness when driving, obesity?
• Pharynx may be narrowed due to enlarged vulva

Question 6

Management of sleep apnoea

Answer 6

Obese patients advised to lose weight

Avoiding alcohol, sedatives a in evening

Question 7

CPAP

Answer 7

Continuous positive airway pressure.
Mask given to patients
- maintains upper airway
- often results in rapid improvement in quality of sleep and resolution of excessive daytime sleepiness.

Question 8

Describe central sleep apnoea

Answer 8

Patients don’t respond to CPAP

Thought to be caused by brainstem pathology

Question 9

Narcolepsy

Answer 9

Irresistable daytime sleepiness.

Question 10

Cataplexy

Answer 10

Sudden onset of muscle weakness when awake, often in response to strong emotions.
Sudden loss of muscle tone leading to head droop or even falling.

Question 11

Hypnagogic hallucinations

Answer 11

Vivid dreams at onset of sleep

Question 12

What may be given to reduce excessive daytime sleepiness

Answer 12

Modafinil

Question 13

Bronchietasis

Answer 13

• Abnormal, permanently dilated airways
• Cycle of neutrophilic inflammation, recurrent infection and damage to airway
• impairs mucociliary clearance

Question 14

What may cause narcolepsy?

Answer 14

Caused by abnormalities of brain neurotransmitter hypocretin (orexin) which regulates arousal, wakefullness and appetite.

Question 15

Restless leg syndrome

Answer 15

Unpleasant sensation of wanting to move the legs. Usually occuring while sitting, lying or resting.

Question 16

Primary sleep disorders encompass…

Answer 16

Periodic leg movements
Restless legs
Sleep apnoea
Narcolepsy

Question 17

What might be given for acute insomnia?

Answer 17

Short half life benzodiazepine.

However should not be used continuously for more than 2 weeks to avoid dependency.

Question 18

Management of obstructive sleep apnoea

Answer 18

• Reduce alcohol intake, exercise, eat earlier
• relaxation
• short half life benzodiazepine
• certain anti histamines
• non benzodiazepine hypnotics; zopiclone
• anti depressants

Question 19

What might be done to measure surface activity of brain?

Answer 19

Electroencephalography

Question 20

Describe REM sleep

Answer 20

Rapid eye movements.
Loss of muscle tone, muscle twitches and rapid eye movements.
Low voltage and increased frequency

Question 21

Describe non-rapid eyemovements

Answer 21

High voltage and low frequency.

Question 22

Describe some sleep diagnostic methods

Answer 22

1. Oximetry, pulse meter
2. Multichannel sleep study, provides info on leg movements, snoring, position, airflow and heart rate.
3. Polysomnography, shows the stage of sleep patient is in

Question 23

Types of sleep apnoea

Answer 23

Obstructive
- Failure of upper airway to maintain adequate patency when upper airway dilator muscles relax with sleep
Central
- patient fails to make effort to breath

Question 24

Describe projections of the hypocretin (orexin) system

Answer 24

1. To cholingeric neurons, reticular formation and spinal cord.
2. To thalamus and basal ganglia
3. To basal forebrain
4. To amygdala and dopaminergic neurons including suprachiasmatic nucleus
5. to locus coeruleus

Thought to promote arousal and limit the REM atonia reflex.