sleep apnoea and neuromuscular respiratory failure

Question 1

What is Obstructive Sleep Apnoea Syndrome?

Answer 1

Recurrent episodes of upper airway obstruction leading to apnoea during sleep
Usually associated with heavy snoring
Typically unrefreshing sleep
Daytime somnolence /sleepiness
Poor daytime concentration

Question 2

why is OSAS important?

Answer 2

Impaired quality of life
Marital dysharmony
Increased risk of RTA’s
Associated with hypertension, increased risk of stroke and probably increased risk of heart disease.

Question 3

whats the prevelance of sleep apnoea?

Answer 3

2% men and 1% women

Question 4

how do you diagnose OSAS?

Answer 4

clinical history and examination
Epworth Questionnaire
Overnight sleep study
pulse oximetry
limited sleep studies
full polysomnography

Question 5

what is the treatment for OSAS?

Answer 5

Identify exacerbating factors
weight reduction
avoidance of alcohol
diagnose and treat endocrine disorders e.g. hypothyroidism, acromegaly

Continuous positive airways pressure (CPAP)
Mandibular repositioning splint

Question 6

are patients with OSAS allowed to drive?

Answer 6

no the DVLA must be informed, when they are satifactorily treated they should be able to drive

Question 7

what are clinical features of OSAS?

Answer 7

Cataplexy
Excessive daytime somnolence
Hypnagogic hallucinations
Sleep paralysis

Question 8

state some treatment

Answer 8

Modafinil
Clomipramine (for cataplexy)
Sodium Oxybate (Xyrem)

Question 9

what are characteristics with chronic ventilatory failure?

Answer 9

Elevated pCO2 (> 6.0 kPA)
pO2 < 8 kPA
Normal blood pH
Elevated bicarbonate

Question 10

what are the causes of airway diseases?

Answer 10

COPD
bronchiectasis
OSA

Question 11

what is the reason for chest wall abnormalities

Answer 11

kyphoscoliosis

Question 12

what is the reason for respiratory muscle weakness

Answer 12

motor neurone disease (ALS)

muscular dystrophy

Question 13

what is the reason for central hypoventilation

Answer 13

obesity hypoventilation syndrome

central hypoventilation syndrome (Ondine’s curse)

Question 14

whats the aetiology for chronic ventilatory failure?

Answer 14

Airways disease
Chest wall abnormalities
Respiratory muscle weakness
Central hypoventilation
Central hypoventilation

Question 15

what are typical symptoms of CVF (i think)

Answer 15

Breathlessness
Orthopnoea
Ankle swelling
Morning headache
Recurrent chest infections
Disturbed sleep

Question 16

what would you find in an examination when looking for CVF

Answer 16

Reflects underlying disease
Particularly look for paradoxical abdominal wall motion in suspected neuromuscular disease
Ankle oedema (hypoxic cor pulmonale)

Question 17

what would you investigate in neuromuscular disease?

Answer 17

Lung function
Lying and standing VC
Mouth pressures / SNIP

Assessment of Hypoventilation
Early morning ABG
Overnight oximetry
transcutaneous CO2 monitoring

(Fluoroscopic screening of diaphragms)

Question 18

whats the treatment for neuromuscular disease?

Answer 18

Domicillary Non Invasive Ventilation (NIV)
Oxygen therapy
(t-IPPV)