Obstructive Sleep Apnoea

Question 1

Definition

Answer 1

Collapse of the pharyngeal airway characterised by episodes of apnoea during sleep, where the person stop breathing periodically for up to a few minutes.

Question 2

Epidemiology and risk factors

Answer 2

Increasing age
Male
Obesity
FHx
Nasopharyngeal obstruction
Craniofacial abnormalities
Macroglossia
Neuromuscular disorders
Lifestyle factors: smoking, alcohol, and sleeping supine
Neuro

Question 3

Pathophysiology

Answer 3

Complete or partial obstruction of the upper airway during sleep. These episodes can cause apnoea or hypopnoea
The majority of patients with OSA have upper airway obstruction at the level of the tongue or the soft palate leading to a loud snoring and apnoea episodes.
The episodic airway obstruction is usually assosciated with oxyhaemoglobin desaturation and arousal from sleep which can lead to fatigue, daytime sleepinesss, and early morning headaches which resolve with time.

Question 4

Signs

Answer 4

• Jaw abnormalities; micrognathia
• Mouth breathing or nasal speech
• Raised BMI and large neck circumference
• Hypertension

Question 5

Symptoms

Answer 5

• Excessive daytime sleepiness
• Snorning
• Unexplained morning headache
• Nocturnal enuresis: despite no increase in fluid intake

Question 6

Diagnosis

Answer 6

• Screening questionnaire: Epworth sleepiness scale or the OSA-50 score
• Complex sleep studies (polysomnography): used to measure = gold standard
• Refer to sleep clinic urgently (ideally to seen within 4 weeks) if adult either has:
  = Excessive sleepiness affecting their roe as a professional driver or other safety-critical worker. These people should be advised not to driver until they’re have been assessed by a specialist
  = A comorbid condition such as COPD, heart failure, pulmonary hypertension o respiratory failure.

Question 7

Treatment

Answer 7

• First line: CPAP for moderate-to-severe OSA and treatment is required long term unless there is associated weight loss sufficient to cause disease remission
• Lifestyle changes: weight loss, stopping smoking, reducing alcohol intake, and avoiding sleeping on their back
• Inform the DVLA: if the patient has suspected or confirmed OSA with excessive daytime seediness they must not drive and must inform the DVLA
• Second line: Intra-oral mandibular advancement devices
• Upper airway surgery: uvulopalatopharyngoplasty (UPPP) = MC, tonsillectomy if is causing nasopharyngeal obstruction

Question 8

Complications

Answer 8

Cardiovascular complications: increased risk of myocardial infarction, stroke, hypertension, and metabolic syndrome secondary to untreated OSA
CPAP complications: conjunctivitis, rhinitis, dermatitis, facial pain and aerophagia