Obstructive Sleep Apnea

Question 1

Definition?

Risk factors for OSA?

Features of OSA?

Assessment of sleep?

Management?

Answer 1

Condition characterised by collapse of pharyngeal airway during the patient’s sleep. As a result, the patient stops breathing for a few minutes during their apnoec episodes during their sleep. This tends to be reported by the patient’s partner as the patient is usually unaware of these episodes.

Risk factors

• Male
• Middle age
• Obese
• Drinks alcohol
• Smoker
• Macroglossia (abnormal enlargement of the tongue) : acromegaly, hypothyroidism, amyloidosis
• Large tonsils
• Marfan’s syndrome

Features of OSA?

• Snoring
• Apnoec episodes during sleep as reported by partner
• Waking up with a morning headache –> feels un-refreshed when waking up
• Daytime sleepiness –> KEY FEATURE
• poor concentration
• reduced oxygen saturations during sleep

Severe cases of OSA can lead to hypertension, heart failure and can increase risk of MI and stroke

Assessment of sleep

• The Epworth sleepiness scale - to be completed by patient +/- partner
• Multiple sleep latency test (MSLT) - a person is given 4-5 opportunities to sleep every two hours during normal wake times. The specialist uses the test to measure the extent of daytime sleepiness (how fast the patient falls asleep in each nap, also called sleep latency), and also how quickly REM sleep begins
• When interviewing someone with potential OSA, always ask for 2 things:
  1) Daytime sleepiness –> this is because its a key feature of the condition
  2) Occupation –> this is because if the patient has an occupation where they need to be on high alert e.g. lorry driver, they need an urgent referral to a sleep clinic/ENT clinic for potential diagnosis and treatment of the condition. Also try and help amend any potential work duties of the individual to reduce their risk to harm. The DVLA should be informed if OSAHS is causing excessive daytime sleepiness.

Management 
- Referral to an ENT specialist or sleep clinic so they can perform sleep studies (polysomnography) on the patient. This involves the patient sleeping in a laboratory where the staff monitor their oxygen levels, snoring levels, heart rate, breathing rate, potential apnoec episodes over night, to determine whether the patient has sleep apnea. 
- Correct reversible risk factors 
 > Stop smoking 
> Stop drinking alcohol 
> Diet and exercise to reduce weight 

• CPAP (continuous positive airway pressure) to ensure airway remains patent
• Intra-oral devices (e.g. mandibular advancements if CPAP is not tolerated or for patients with mild OSAHS where there is no daytime sleepiness.
• Surgery - in very severe cases where there is reconstruction of the soft palate and the jaw
  > UPPP (uvulopalatopharyngeoplasty)