Normal sleep consists of 4 phases:
Falling asleep – Very deep sleep – REM (rapid eye movements) – Awakening or Arousal.
4-6 cycles of these phases every night give sound sleep with a fresh feeling on awakening.
These normal cycles are disturbed when the brain does not get enough oxygen secondary to obstruction to breathing during sleep. Normally the pharyngeal muscles are taut and contracted during the wakeful state. During sleep like all skeletal muscles of the body, the pharyngeal muscle gets flaccid. In obese individual or in short neck people, this flaccidity can obstruct the air passage causing repeated apnoeas or cessation of breathing for a few seconds. This sleep disorder in which breathing repeatedly stops & starts is called Obstructive Sleep Apnoea.
Loud snoring due to vibrations of closed air passages is an “alert” to OSA.
Snoring is disturbing for the person sleeping next to the snorer. It signifies difficulty in breathing during sleep, and there are episodes of choking or gasping several times during sleep, called Obstructive Sleep Apnoea.
How to recognize Obstructive Sleep Apnoea?
– Restlessness. The person might find it difficult to stay asleep or maybe restless during sleep if disturbed by OSA.
– Sudden waking up – Due to loss of breath, the person might wake up feeling choked causing a break in sleep.
– Frequent visits to the bathroom.
– Frequently waking up to drink water.
– Loud persistent snoring.
- Day time sleepiness – Waking up feeling low on energy, and feeling sleep deprived.
- Bad headaches every morning after waking up signals OSA. Due to low oxygen levels, blood vessels can widen-up causing these headaches.
- Dry throat – Dry or sore throat on awakening are signs of OSA. Dry mouth can be a result of breathing through the mouth.
- Mood swings – Not getting quality sleep almost every night can make a person irritated or susceptible to these mood swings. If not attended on time, this can lead to depression.
- Loss of attention – OSA affects cognitive functions, making it difficult for a person to concentrate for long, and even cause amnesia for some.
Test to be done is called Sleep Study or Polysomnography that can detect breathing obstruction during sleep.
How can we prevent or treat OSA?
For milder cases of obstructive sleep apnoea, management consists of:-
- Weight loss decreases the fat around the pharynx.
- Exercise tones the muscles and increases the neuro muscular transmitters to the breathing apparatus.
- Drink alcohol modestly.
- Quit-smoking – The ingredients in smoke can cause further constriction of air passages.
- Use of nasal decongestant or allergy medications.
- Sleeping on the side instead of the back.
All patients should be offered Nasal CPAP therapy first. In patients with mild to severe obstructive sleep apnoea, who refuse or reject nasal CPAP therapy, BIPAP therapy should be tried next.
What is CPAP? (Continuous Positive Airway Pressure)
Continuous Positive Airway Pressure is a form of positive airway pressure ventilator a kind of sleep therapy machine, which helps a person of OSA to breathe more easily during sleep. It increases air pressure in the throat so that the airway does not collapse when you breathe in. It does this by applying mild air pressure on a continuous basis to keep the airways continuously open in people who are not able to breathe spontaneously on their own.
A CPAP machine uses a hose and mask or nose piece to deliver constant and steady air pressure. (Common problems with CPAP include a leaky mask, stuffy nose, dry mouth and trouble falling asleep).
The air pressure keeps the throat muscles from collapsing and reducing obstructions by acting as a splint.
Bilevel PAP: BIPAP machines have 2 level settings – The prescribed pressure for inhalation (ipap) and a lower pressure for exhalation (epap). The dual settings allow the patient to get more air in and out of their lungs.