Obstructive sleep apnoea is a potentially serious sleep disorder. It causes breathing to repeatedly stop and start during sleep. Most common type of sleep apnoea is obstructive. This type of apnoea occurs when throat muscles intermittently relax and block the airway during sleep. A noticeable sign of obstructive sleep apnoea is snoring. Treatments are available for this condition. Many people may not think of snoring as a sign of something potentially serious, and not everyone who snores has obstructive sleep apnoea. But it is always necessary to get a proper diagnosis.
Signs & symptoms
- Excessive daytime sleepiness
- Loud snoring
- Observed episodes of stopped breathing during sleep
- Abrupt awakenings accompanied by gasping or choking
- Awakening with a dry mouth or sore throat
- Morning headache
- Difficulty concentrating during the day
- Experiencing mood changes, such as depression or irritability
- High blood pressure
- Excessive sweating at night time
- Decreased libido
Obstructive sleep apnoea occurs when the muscles in the back of the throat relax too much to allow normal breathing. The repeated opening and closure interrupts breathing, oxygen supply and sleep. Anyone can develop obstructive sleep apnoea. However, certain factors make the person at increased risk, including:
- Excess weight – However, not everyone with obstructive sleep apnoea is overweight and vice versa. Thin people can develop the disorder, too.
- Narrowed airway by birth or due to enlarged tonsils or adenoids
- High blood pressure (hypertension)
- Chronic nasal congestion
- In general, men are twice as likely as premenopausal women to have obstructive sleep apnoea. The frequency of obstructive sleep apnoea increases in women after menopause.
- A family history of sleep apnoea
OSA is caused by soft tissue collapse in the pharynx.Transmural pressure is the difference between intraluminal pressure and the surrounding tissue pressure. If transmural pressure decreases, the cross-sectional area of the pharynx decreases. If this pressure passes a critical point, pharyngeal closing pressure is reached. Exceeding pharyngeal critical pressure causes a juggernaut of tissues collapsing inward. The airway is obstructed. Until forces change transmural pressure to a net tissue force that is less than pharyngeal critical pressure, the airway remains obstructed. OSA duration is equal to the time that pharyngeal critical pressure is exceeded.
Most patients with OSA demonstrate upper airway obstruction at either the level of the soft palate (nasopharynx) or the tongue (oropharynx). Research indicates that both anatomic and neuromuscular factors are important.
Anatomic factors like enlarged tonsils, volume of the tongue, soft tissue, or lateral pharyngeal walls, length of the soft palate, abnormal positioning of the maxilla and mandible etc. may each contribute to a decrease in the cross-sectional area of the upper airway and/or increase the pressure surrounding the airway, both of which predispose the airway to collapse. Enlarged tonsils and adenoids are the most common cause of OSA in children but note that in adults, it is very rare for to be a cause of OSA.
Neuromuscular activity in the upper airway, including reflex activity, decreases with sleep, and this decrease may be more pronounced in patients with OSA. Reduced ventilatory motor output to upper airway muscles is believed to be the critical initiating event leading to upper airway obstruction.
Static and dynamic pathophysiologic factors
Both static factors and dynamic factors are involved in the development of OSA. Static factors include surface adhesive forces, neck and jaw posture, tracheal tug, and gravity. Any anatomic feature that decreases the size of the pharynx (e.g., retrognathia) increases the likelihood of OSA. Gravitational forces are felt simply by tilting one’s head back to where the retro-position of the tongue and soft palate reduce the pharyngeal space. For most patients, OSA worsens in the supine sleeping position.
An important static factor that has been found is the reduced diameter of the pharyngeal airway in wakefulness in OSA patients compared with non-OSA patients. In the absence of craniofacial abnormalities, the soft palate, tongue, parapharyngeal fat pads, and lateral pharyngeal walls are enlarged in OSA patients versus non-OSA patients.
Dynamic factors include nasal and pharyngeal airway resistance, the Bernoulli effect, and dynamic adherence.
The Bernoulli effect plays an important dynamic role in OSA pathophysiology. In accordance with this effect, airflow velocity increases at the site of stricture in the airway. As airway velocity increases, pressure on the lateral wall decreases. If the transmural closing pressure is reached, the airway collapses. The Bernoulli effect is exaggerated in areas where the airway is most compliant. Loads on the pharyngeal walls increase adherence and, hence, increase the likelihood of collapse.
This effect helps to partially explain why obese patients, and particularly those with fat deposition in the neck, are most likely to have OSA.
However, the clinical situation is complex because of the interplay of known static and dynamic factors and because of unknown factors.
Apnoea clusters and oxygen desaturation
OSA often occurs in clusters. An oxygen desaturation occurs with each apnoea. In patients with severe OSA, the cluster of apnoea occurs throughout sleep. The desaturation from the first apnoea event is typically associated with a higher desaturation percentage change than subsequent apnoea in the series.
Studies found that oxygen desaturation was not significantly correlated with resting oxygen saturation, independent of mixed-venous oxygen saturation, using forward stepwise regression modelling. It predicted increased desaturation rates solely based on the size of oxygen reuptake. This occurs when mixed-venous blood with depleted oxygen saturation arrives at the lung in time with the apnoea phase.
The rapid change in oxygen desaturation occurred after the second apnoea in a series of 10 produced; apnoea that followed the second apnoea did not have accelerated changes when compared with the second apnoea. Isolated apnoea did not show rapid changes in oxygen saturation.
The clinical implications of these findings suggest that the reason why continuous positive airway pressure (CPAP) and supplemental oxygen may work to ameliorate rapid desaturation is related to the extent that apnoea can remain isolated. This results in a longer ventilatory phase to allow venous reoxygenation.
Genetic studies have revealed that the gene that encodes for oxidative stress uniquely contributes toward OSA. The gene may play a pivotal role by operating in a positive feedback loop, causing the OSA to begin with and then triggering an inflammatory response that further narrows the upper airways, exacerbating the OSA.
Tests to detect obstructive sleep apnoea include:
- Polysomnography (sleep study) – an equipment that monitors heart, lung and brain activity, breathing patterns, arm and leg movements, and blood oxygen levels while the person is asleep.
For milder cases of obstructive sleep apnoea, lifestyle changes will be enough, such as:
- Losing overweight.
- Regular exercise.
- Avoid alcohol intake. If a must, drink moderately, if at all, and don’t drink several hours before bedtime.
- Quit smoking.
- Use a nasal decongestant or allergy medications.
- Don’t sleep on the back. Use comfortable cushions and pillows.
- Avoid taking sedative medications such as anti-anxiety drugs or sleeping pills
Therapies including devices
Positive airway pressure – In this treatment, a machine delivers air pressure through a piece that fits into the nose or is placed over the nose and mouth while sleeping.
The most common type is called continuous positive airway pressure, or CPAP. With this treatment, the pressure of the air breathed is continuous, constant and somewhat greater than that of the surrounding air, which is just enough to keep the upper airway passages open. This air pressure prevents obstructive sleep apnoea and snoring. Using a humidifier along with the CPAP system also will be helpful.
CPAP may be given at a continuous (fixed) pressure or varied (autotitrating) pressure. In fixed CPAP, the pressure stays constant. In autotitrating CPAP, the levels of pressure are adjusted if the device senses increased airway resistance.
- Mouthpiece (oral device). Though positive airway pressure is often an effective treatment, oral appliances are an alternative for some people with mild or moderate obstructive sleep apnoea.
These devices are designed to keep the throat open. Some devices keep the airway open by bringing the lower jaw forward, which can sometimes relieve snoring and obstructive sleep apnoea. Other devices hold the tongue in a different position.
Close follow-up is needed to ensure successful treatment.
Nasal pillow mask
Nasal pillows fit at the nares to supply air pressure.
It is usable if the person:
- feels claustrophobic in masks that cover more of the face
- wants a full field of vision for reading or watching TV
- wants to wear your glasses
- has facial hair that interferes with other masks
Surgery or other procedures
Surgery is usually considered only if other therapies don’t work. Surgical options may include:
- Surgical removal of tissue. Uvulopalatopharyngoplasty – removes tissue from the back of the mouth and top of the throat. Tonsils and adenoids may be removed as well. UPPP usually is performed in a hospital and requires a general anaesthesia.
Tissue is removed from the back of the throat with a laser (laser-assisted uvulopalatoplasty) or with radiofrequency energy (radiofrequency ablation) to treat snoring. These procedures don’t treat obstructive sleep apnoea, but they may reduce snoring.
- Upper airway stimulation. This new device is approved for use in people with moderate to severe obstructive sleep apnoea who can’t tolerate CPAP.
A small, thin impulse generator (hypoglossal nerve stimulator) is implanted under the skin in the upper chest. The device detects the breathing patterns and, when necessary, stimulates the nerve that controls movement of the tongue.
Studies have found that upper airway stimulation leads to significant improvement in obstructive sleep apnoea symptoms and improvements in quality of life.
- Jaw surgery (maxillomandibular advancement). In this procedure, the upper and lower parts of the jaw are moved forward from the rest of the facial bones. This enlarges the space behind the tongue and soft palate, making obstruction less likely.
- Surgical opening in the neck (tracheostomy) – It is done in severe, life-threatening obstructive sleep apnoea.
During a tracheostomy, the surgeon makes an opening in the neck and inserts a metal or plastic tube through which the person can breathe. Air passes in and out of the lungs, bypassing the blocked air passage in the throat.
- Implants. This minimally invasive treatment involves placement of three tiny polyester rods in the soft palate. These inserts stiffen and support the tissue of the soft palate and reduce upper airway collapse and snoring. This treatment is recommended only for people with mild obstructive sleep apnoea.
Other types of surgery may help reduce snoring and sleep apnoea by clearing or enlarging air passages, including:
- Nasal surgery to remove polyps or straighten a crooked partition between the nostrils (deviated septum)
- Surgery to remove enlarged tonsils or adenoids
The short-term prognosis, in relation to symptoms such as daytime sleepiness and snoring, ranges from good to excellent with regular use of CPAP.
The long-term prognosis is unknown because no randomized treatment studies investigating the effect of CPAP on preventing the development of cardiovascular sequelae have been conducted.
- Daytime fatigue and sleepiness
- Attention and behavioural problems
- Cardiovascular problems like high blood pressure (hypertension), which can increase the risk of heart disease.
- Risk of coronary artery disease, heart attack, arrhythmia, sudden death due to cardiac arrest, heart failure and stroke.
- Complications with medications and surgery. Obstructive sleep apnoea also is a concern with certain medications and general anaesthesia.
- Eye problems such as glaucoma
- memory problems
- morning headaches
- mood swings
- feelings of depression
- need to urinate frequently at night (nocturia).
Disease & Ayurveda
Kaasavruddhi – Recurrent non-healing cough & upper respiratory tract infections
Aamatisaara – indigestion & diarrhoea
Vamathu – Vomiting
Visha – Intoxication
Pandu – Anaemia
Jwara – Fever
Marmaaghata – Injury to vital points
Atihimambu – Drinking excess cold water
Hrithpaarswasoola – Pain in chest & flanks
Praanavilomata – Obstruction to the channels of Praana (Life force or oxygen)
Aanaha – Distension of upper abdomen
Sankhabheda – Severe pain in sides of forehead & temples
When the excessive vitiated kapha causes obstruction in channels in chest, it vitiates the channels that carry oxygen, water and water. It when gets lodged in the chest and upper airways, produce the disease.
Swaasa – Difficulty in breathing
First line of Ayurveda treatment for any kind of breathing difficulty is removing the blockage in channels caused by vitiated excess Kaphadosha. If the kaphadosha is dried up and sticky in the walls of channels, it is important to liquify it, bring it flowing out to the alimentary tract and expel out from the body. Once the causative block in channels is removed, next line of treatment is to give strength to muscles and tissues of respiratory system. Even after gaining normal breathing, avoiding causative factors and maintaining good life style is important.
Internal medicines and fasting for aamapaachana
Usage of rooksha(dry) & tikta(bitter) drugs
As there is a large amount of vitiated Kapha get accumulated in the chest and upper airways, sodhana therapies to clean the channels are essential in breathing disorders. It includes:
Rookshaswedas like pindasweda
After the Kaphadosha is cleared, medicines like ksheerabala and dasamoolaksheerapaaka are used to give strength to muscles and regain normal tonicity & elasticity. Goat’s milk (processed with herbs) is also advised for intake.
Commonly used medicines
- Maintain a healthy weight, get rid of obesity
- Exercise on a regular basis
- Avoid alcohol and medications such as anti-anxiety drugs and sleeping pills
- Sleep on your side or stomach rather than on your back
- Keep your nasal passages open while you sleep by using a saline nasal spray or so
- To be avoided
Heavy meals and difficult to digest foods – cause indigestion.
Junk foods- cause disturbance in digestion and reduces the bioavailability of the medicine
Carbonated drinks – makes the stomach more acidic and disturbed digestion
Refrigerated and frozen foods – causes weak and sluggish digestion by weakening Agni (digestive fire)
Milk and milk products – increase kapha, cause obstruction in channels and obesity
Curd – causes vidaaha and thereby many other diseases
- To be added
Light meals and easily digestible foods
Green gram, soups, honey
Freshly cooked and warm food processed with cumin seeds, ginger, black pepper, ajwain etc
Protect yourself from cold climate.
Better to avoid exposure to excessive sunlight wind rain or dust.
Maintain a regular food and sleep schedule.
Avoid holding or forcing the urges like urine, faeces, cough, sneeze etc.
Avoid sedentary lifestyle.
Regular stretching and mild cardio exercises are advised. Also, specific yogacharya including naadisuddhi pranayama, bhujangaasana, pavanamuktasana is recommended.
Regular exercise helps improve bioavailability of the medicine and food ingested and leads to positive health.
Yoga can maintain harmony within the body and with the surrounding system.
Simple exercises for lungs and heart health
All the exercises and physical exertions must be decided and done under the supervision of a medical expert only.