Sleep Apnoea and Neuromuscular Respiratory Failure Flashcards
Features of Sleep Apnoea (5)
Heavy snoring Unrefreshing sleep Daytime somnolence Poor daytime concentration Obstruction between the pharyngeal wall and soft palette
Pathophysiology (5)
Muscle relaxation Narrow pharynx Obesity Snoring Oxygen desaturation
Definition of Apnoea
Complete obstruction
Definition of Hypopneas
Partial obstruction
Importance of treating OSAS
Impaired quality of life Marital disharmony Increased risk of road traffic accident Hypertension Increased risk of stroke and heart disease
Diagnosis
Clinical history and examination
Epworth questionnaire
Overnight sleep study
Polysomnography
What is a Epworth questionnaire
a questionnaire with a scale marked out of 24 where patients grade themselves how likely they are to fall asleep in 8 situation
What is carried out in an overnight sleep study
Pulse oximetry- monitors oxygen saturation of a patient’s blood
Limited sleep studies
Full polysomnography
What is a polysomnography
Gold standard
Records brain waves overnight
Apnoea index
Oronasal airflow
What is the Apnoea index
Apnoea + Hypopnea events / Hours of sleep
Other investigations for Sleep Apnoea
Thoracoabdominal movement ECG Audio-visual recording EOG EMG ECG
Normal Apnoea index
0-5
Mild Apnoea index
5-15
Moderate Apnoea index
15-30
Severe Apnoea index
> 30
Treatment (5)
Weight reduction Avoidance of alcohol Diagnose and treat endocrine disorders e.g. hyperthyroidism acromegaly Continuous positive airways pressure Mandibular repositioning splint
What is Narcolepsy
A sleep disorder characterised by excessive sleepiness, sleep paralysis, hallucinations and in some cases cataplexy
What is the genetics of narcolepsy
Familial
Associated with HLA- DRB11501 and HLADQB10602
Clinical features of narcolepsy
Cataplexy
Excessive daytime somnolence
Hypnagogic hallucinations
Sleep Paralysis
Treatment of Narcolepsy
Modafinil- promote wakefulness
Clomipramine (for cataplexy)
Sodium Oxybate (Xyrem)
Features of Chronic Ventilatory Failure
Elevated PCO2
Low PO2
Normal blood PH
Elevated bicarbonate
Why is bicarbonate elevated and Co2 high in CVF
Bicarbonate is release to buffer the excess CO2 which reduced the respiratory drive and leads to respiratory hypoventilation
Aetiology of CVF
COPD Bronchiectasis OSA Kyphoscoliosis Motor neurone disease (ALS) Muscular dystrophy Obesity hypoventilation syndrome Ondine's curse
Symptoms of CVF
SOB Orthopnea Ankle swelling Morning headache Recurrent chest infections Disturbed sleep
