Need for increasing awareness of Obstructive Sleep Apnoea(OSA)

  • OSA is a public health threat about which very few people are aware. In fact, as many as 90 percent of people with this disorder are currently undiagnosed and untreated
  • The prevalence of OSA in the Indian population is three-fold higher in men as compared to women. The prevalence of OSA increases with age, though age is not an independent risk factor for the OSA.
  • Sleep disorders are common
  • Sleep disorders are serious
  • Sleep disorders are treatable
  • Sleep disorders are under diagnosed
  • OSA is characterized by episodes of complete or partial pharyngeal obstruction during sleep. When these apneas and hypopneas are combined with symptoms such as day time somnolence, the term obstructive sleep apnea-hypopnea syndrome is applied.
  • Multiple sites of obstruction often occur in patients with obstructive sleep apnea. An elongated and enlarged soft palate impinges on the posterior airway at the level of the nasopharynx and oral pharynx. In addition, a retruding jaw pushes an enlarged tongue posteriorly to impinge on the hypopharyngeal space.

Obstructive Sleep Apnea Syndrome – Overview

Demographics

  • –4% males, 2% females
  • –Mainly middle-aged, overweight males
  • –Neck circumference >42cm
  • –BMI >30

Common features of patients with sleep apnea

  • Loud snoring
  • Disrupted sleep
  • Nocturnal gasping and choking
  • Witnessed apnea
  • Daytime sleepiness and fatigue
  • Crowded posterior airway
  • Short, thick neck

Obstruction of pharynx during sleep

  • The site of upper airway obstruction lies in pharynx
  • Size of pharyngeal lumen during inspiration depends on balance between inward or narrowing ,forces resulting from intrapharyngeal suction pressure and outward, or dilating forces generated principally by pharyngeal muscles
  • Anatomical abnormalities of pharynx and its associated structures

Obstructive Sleep Apnea Syndrome

Diagnosis

  • –Cessation of airflow >10 s (in adults) with respiratory effort and terminated by an arousal and/or desaturation
  • –Respiratory Disturbance Index (RDI) > 5 events/hour of sleep time
  • –Worse during supine REM
  • –30-50% reduction in airflow (hypopnea) for a minimum of 10 seconds terminated by an arousal or followed by a minimum of 2% fall in oxygen saturation

Treatment –

Continous positive airway Pressure,CPAP