Sleep Apnoea and Neuromuscular Respiratory Failure - Adults Flashcards
What are the symptoms of Obstructive Sleep Apnoea?
Recurrent episodes of upper airways obstruction leading to apnoea during sleep Heavy snoring Unrefreshing sleep Daytime somnolence (sleepiness) Poor daytime concentration
What three factors can leads to repeated closure of the upper airway?
Muscle relaxation
Narrow pharynx
Obesity
What can repeated closure of the upper airways lead to?
Oxygen desaturation
Apnoeas
Snoring
What causes poor concentration and daytime hypersomnolence?
Apnoeas causing frequent microarousals
How does OSAS impact a persons life?
Worse QOL
Marital disharmony
Risk of RTAs
Associated with HPT, increased risk of stroke and heart disease
What is apnoea?
Momentary stop in breathing
How is OSAS diagnosed?
Clinical history and examination
Epworth questionnaire
Overnight sleep study
What are 3 different overnight sleep studies?
Pulse oximetry
Limited sleep study
Full polysomnography
What is hypopnoea?
Partial apnoeas, shallow breathing and low respiratory rate
What equipment is used in a polysomnography?
EEG - stages sleep through night
EOG - measures eye movement
EMG - measures muscle movement
ECG - heart rate
What are the values for desaturation rate?
Normal: 0-5
Mild: 5-15
Moderate: 15-30
Severe: > 30
What are exacerbating factors?
Weight reduction
Avoidance of alcohol
Diagnose and treat endocrine disorders i.e. hypothyroidism, acromegaly
What are 3 measures of treatment on OSAS?
Identify exacerbating factors
Continuous positive airways pressure (CPAP)
Mandibular repositioning splint
What are the clinical features of narcolepsy?
Cataplexy
Daytime somnolence
Hypnagogic hallucinations
Sleep paralysis
What are hypnagogic hallucinations?
Visual hallucinations when about to fall asleep or waking up
What is the treatment of narcolepsy?
Modafinil
Clomipramine (cataplexy)
Sodium oxybate (xyrem)
What is cataplexy?
Strong emotion or laughter causes a person to suffer sudden physical collapse though remaining conscious.
What are the signs of chronic ventilatory failure?
Elevated pCO2 (> 6kPa)
pO2 < 8 kPa
Normal blood pH
Elevated bicarbonate
Name 3 airway diseases that cause chronic ventilatory failure
COPD
Bronchiectasis
OSA
Name a chest wall abnormality that causes chronic ventilatory failure
Kyphosis
Name 2 respiratory muscle weakness which cause chronic ventilatory failure
Motor neurone disease (ALS)
Muscular dystrophy
Name 2 central hypoventilation problems that cause chronic ventilatory failure
Obesity hypoventilation syndrome - BMI > 35
Central hypoventilation syndrome
What are symptoms of chronic ventilatory failure?
SOB Orthopnoea Ankle swelling - cor pulmonale symptom Morning headache Recurrent chest infections Disturbed sleep
What are signs of chronic ventilatory failure?
Reflects underlying disease Look for paradoxical abdominal wall motion in suspected neuromuscular disease Ankle oedema (hypoxic cor pulmonale)
What are investigations for chronic respiratory failure?
Lung function
Assessment of Hypoventilation
(Fluoroscopic screening of diaphragm)
What is the treatment for chronic ventilatory failure?
Domicillary non-invasive ventilation (NIV) - applies high inspiratory pressure and low exp pressure
Oxygen failure
