Flashcards in Sleep apnoea Deck (6)
Define obstructive sleep apnoea
Upper airway narrowing that is provoked by sleep. This causes sleep deprivation with consequent daytime sleepiness and impaired intellectual performance.
Explain the aetiology of obstructive sleep apnoea
Excessive narrowing with relaxation during sleep:
-Neuromuscular: stroke, MND, myotonic dystrophy
-Sedatives, alcohol, opioids
Normal narrowing of a small pharynx during sleep:
-Increased neck fat and/or muscle bulk
-Craniofacial abnormalities, rhinitis, polyps
Describe the presentation of obstructive sleep apnoea
Snoring and apnoea attacks often witness by partner
Excessive daytime sleepiness (Epworth >9)
Impaired intellectual performance
Hypoxia and hypercapnia: corrected on arousal
Raised BP following arousal and in daytime
Less common: nocturnal sweating, reduced libido, reflux
How is obstructive sleep apnoea diagnosed?
Co-lateral history from relatives/partners
Epworth sleepiness scale: discriminate from snoring
Overnight pulse oximetry: sawtooth appearance
Sleep studies: primarily for research
Diagnosis confirmed if 10-15 or more apnoeas or hyponoeas in any 1 hour of sleep
Outline the management of obstructive sleep apnoea
Treatment based on symptoms and QoL
Treat modifiable factors: obesity, acromegaly, nasal polyps etc.
Lifestyle: Weight loss, sleep on side, avoid alcohol and caffeine in evenings.
Snorers/mild OSA: mandibular advancement device
Significant OSA: nasal CPAP, consider bariatric surgery (gastric band, gastric bypass, sleeve gastrectomy)
Severe OSA and hypercapnia: CPAP +/- NIV