SLEEP MEDICINE

We usually hear about sudden heart attacks and related deaths even in young people irrespective of age and sex, especially during sleep. These deaths are commonly labelled as Myocardial Infarctions, but 75% of these unfortunate deaths could have been avoided if they were diagnosed from a fatal disease called OBSTRUCTIVE SLEEP APNEA (OSA).

What is OSA?

It is the condition where the person is not able to breathe normally at sleep due to an airway obstruction. The obstruction can be Polyp, DNS (deviated nasal septum), Adenoids, Macroglossia, Posterior Mandibular positioning, Tonsillitis , long Uvula, even enlarged Neck circumference.

When your body is at rest during sleep, mandible falls back pulling the tongue backward. When the tongue falls back, it vibrates hitting the small tongue (UVULA) creating a snoring sound. This could increase the load of the heart. A person having such a condition would feel breathless when they exert a little extra effort during a physical activity like climbing stairs. This could end up in a possible cardiac arrest if it’s continuous. Due to the persisting airway block, oxygen will be at a lower level and the carbon dioxide level increases within the body. This situation is called HYPERCAPNEA and that is known as a DESATURATION event. This is sensed by the brain as a dangerous event and it will respond by forcing the tongue to move forward . The tongue while moving forward pulls the lower jaw which will result in subsequent CLENCHING or BRUXISM.

Clenching/bruxism while sleeping is virtually a physiological response of the human body to balance the ill effect of OSA . The TMJ would be further deteriorated due to the pressure exerted within the TMJ complex. 80% of the patients suffer from OSA related clenching / bruxism and they are not aware of it.

DIAGNOSIS OF OBSTRUCTIVE SLEEP APNEA (OSA)

• Physical examination and history
• Examination of the back of throat, nose and mouth for extra tissue or abnormality, measurement of the neck and waist circumference, weight imbalance.
• Radiographs- LATERAL CEPHALOGRAM for airway patency, AIRWAY CBCT VOLUMETRY, 3D CT TMJ/AIRWAY.

• Extra oral and intra oral examination.

• Questionnaire.

• Postural examination

• ‘SLEEP STUDY (HST – HOME SLEEP TEST OR POLYSOMNOGRAPHY)

Interpretation from the sleep report would be AHI (Apnea-Hypopnea Index) and the number of desaturations.