Sleep apnea is a sleep disorder accompanied by episodes of stopping rhinoceros breathing lasting at least 10 seconds. With sleep apnea, from 5 to 60 or more short-term stops of breathing can be recorded. There is also snoring, restless night sleep, daytime drowsiness, decreased performance. The presence of sleep apnea is detected during polysomnography, and its causes are detected during an otorhinolaryngological examination. For the treatment of sleep apnea, non-medicinal (special oral devices, oxygen therapy), medicinal and surgical methods aimed at eliminating the cause of the disorder are used.
ICD 10
G47.3 Sleep Apnea
Meaning
Sleep apnea (SA) is a disorder of respiratory function characterized by periodic stops of breathing during sleep. In addition to night stops of breathing, disease is characterized by constant heavy snoring and pronounced daytime drowsiness. Respiratory arrest during sleep is a potentially life-threatening condition accompanied by hemodynamic disorders and unstable cardiac activity.
Breathing pauses lasting 10 seconds in SA cause hypoxia (lack of oxygen) and hypoxemia (increased carbon dioxide), stimulating the brain, which leads to frequent awakenings and resumption of breathing. After falling asleep again, a short-term respiratory arrest and awakening follows. The number of episodes of apnea depends on the severity of the disorders and can be repeated from 5 to 100 times per hour, adding up to the total duration of breathing pauses up to 3-4 hours per night. The development of SA disrupts the normal physiology of sleep, making it intermittent, superficial, uncomfortable.
According to statistics, pathology affects 4% of men and 2% of middle-aged women, with age the probability of apnea increases. Women are most prone to developing apnea during menopause. Respiratory dysfunction close to apnea is hypnosis – a decrease in the volume of respiratory flow by 30% or more compared to normal for 10 seconds, leading to a decrease in oxygen perfusion by more than 4%. In healthy individuals, physiological apnea occurs – short, intermittent stops of breathing during sleep lasting no more than 10 seconds and with a frequency of no more than 5 per hour, which are considered a variant of the norm and do not threaten health. Solving the problem requires the integration of efforts and knowledge in the field of otorhinolaryngology, pulmonology, somnology.
Causes of sleep apnea
Violations of the regulation of respiratory function by the central nervous system in central sleep apnea can be caused by injuries, compression of the brain stem and posterior cranial fossa, brain lesions in Alzheimer’s-Peak syndrome, postencephalitic parkinsonism. In children, there is a primary insufficiency of the respiratory center, causing alveolar hypoventilation syndrome, in which cyanotic skin is observed, episodes of sleep apnea in the absence of pulmonary or cardiac pathology.
Obstructive form is more common in people suffering from obesity, endocrine disorders, and prone to frequent stress. Anatomical features of the upper respiratory tract predispose to the development of obstructive sleep apnea: short thick neck, narrow nasal passages, enlarged soft palate, tonsils or palatal uvula. In the development of pathology, a hereditary factor is important.
Pathogenesis
The development of obstructive sleep apnea occurs as a result of pharyngeal collapse that occurs during deep sleep. The collapse of the airways at the pharyngeal level during each episode of apnea causes states of hypoxia and hypercapnia, signaling to the brain about the need to wake up. During awakening, the air-carrying function and ventilation of the lungs are restored. Violations of the patency of the upper airways can develop behind the soft palate or the root of the tongue, between the back wall of the pharynx and choanas – internal nasal openings, at the level of the epiglottis.
Classification
According to the pathogenetic mechanism of the development of sleep apnea, its central, obstructive and mixed forms are distinguished. Central sleep apnea develops as a result of a violation of the central mechanisms of respiratory regulation due to organic brain lesions or primary insufficiency of the respiratory center. Sleep apnea in the central form of the syndrome is caused by the cessation of the intake of nerve impulses to the respiratory muscles. The same mechanism of development underlies the periodic Chain-Stokes breathing, which is characterized by alternation of superficial and rare respiratory movements with frequent and deep, then turning into apnea.
Obstructive form develops due to the decline or occlusion of the upper respiratory tract while maintaining respiratory regulation by the central nervous system and the activity of the respiratory muscles. Some authors include obstructive form in the syndrome complex of obstructive apnea-hypnosis, which also includes a number of respiratory dysfunctions that develop during sleep:
- Hypoventilation syndrome is characterized by a steady decrease in lung ventilation and blood perfusion with oxygen.
- Pathological snoring syndrome
- Obesity-hypoventilation form is a gas exchange disorder that develops against the background of excessive weight gain and is accompanied by a persistent decrease in blood perfusion with oxygen with daytime and night hypoxemia.
- The syndrome of combined obstruction of the respiratory tract is a combination of violations of the patency of the upper (at the level of the pharynx) and lower (at the level of the bronchi) respiratory tract, leading to the development of hypoxemia.
Mixed sleep apnea involves a combination of central and obstructive mechanisms. According to the number of episodes of apnea, the severity of the sleep apnea is determined:
- up to 5 episodes of apnea per hour (or up to 15 apnea-hypopnea) – there is no SA;
- from 5 to 15 apnea per hour (or from 15 to 30 apnea-hypopnea) – mild SA;
- from 15 to 30 apnea per hour (or from 30 to 60 apnea-hypopnea) – moderate SA;
- more than 30 apnea per hour (or more than 60 apnea-hypnosis) is a severe SA.
Symptoms of sleep apnea
Often, patients themselves are unaware of their disease and learn about it from those who sleep nearby. The main manifestations are snoring, restless and intermittent sleep with frequent awakenings, episodes of respiratory arrest during sleep (according to persons surrounding the patient), excessive motor activity during sleep.
As a result of inadequate sleep, patients develop neurophysiological disorders, manifested by headaches in the morning, fatigue, excessive daytime sleepiness, decreased performance, irritability, fatigue during the day, decreased memory and concentration.
Over time, patients suffering from sleep apnea increase their body weight and develop sexual dysfunction. Pathology negatively affects cardiac function, contributing to the development of arrhythmias, heart failure, angina attacks. Half of the patients with sleep apnea have concomitant pathology (arterial hypertension, coronary artery disease, bronchial asthma, chronic obstructive pulmonary disease, etc.), significantly aggravating the course of the syndrome. The development of sleep apnea is often found in Pickwicke syndrome, a disease that combines insufficiency of the right parts of the heart, obesity and daytime drowsiness.
In children, sleep apnea may be indicated by breathing through the mouth during the daytime, night and daytime urinary incontinence, excessive sweating during sleep, drowsiness and slowness, behavioral disorders, sleeping in unusual poses, snoring.
Complications
Sleep disorders with sleep apnea can seriously affect the quality of life. A decrease in concentration during the daytime increases the risk of injuries and accidents at work, at home and in everyday activities.
An increase in the frequency of apnea episodes directly affects the increase in morning blood pressure. During respiratory pauses, a heart rhythm disorder may develop. Increasingly, disease is called the cause of stroke in young men, ischemia and myocardial infarction in patients with atherosclerosis. Pathology aggravates the course and prognosis of chronic pulmonary pathology: COPD, bronchial asthma, chronic obstructive bronchitis, etc.
Diagnostics of sleep apnea
In the recognition of sleep apnea, contact with the patient’s relatives and their participation in establishing the fact of respiratory arrest during sleep is important. To diagnose sleep apnea in outpatient practice, the method of V. I. Rovinsky is used: one of the relatives during the patient’s sleep marks the duration of breathing pauses with the help of a watch with a second hand.
During examination, patients usually have a body mass index (BMI) > 35, which corresponds to the II degree of obesity, neck circumference > 40 cm in women and 43 cm in men, blood pressure indicators exceed 140/90 mm Hg.
Patients are consulted by an otolaryngologist, during which pathology of ENT organs is often revealed: rhinitis, sinusitis, curvature of the nasal septum, chronic tonsillitis, polyposis, etc. Nasopharyngeal examination is complemented by pharyngoscopy, laryngoscopy and rhinoscopy using a flexible fibroendoscope.
A reliable picture of the presence of sleep apnea can be established by conducting a polysomnographic study. Polysomnography combines long-term (over 8 hours) simultaneous recording of electrical potentials (brain EEG, ECG, electromyograms, electrooculograms) and respiratory activity (air flows passing through the mouth and nose, respiratory efforts of abdominal and thoracic muscles, oxygen saturation (SaO 2) of blood, the phenomenon of snoring, body posture during sleep time). When analyzing the polysomnography record, the number and duration of sleep apnea episodes and the severity of the changes occurring during this are determined.
A variant of polysomnography is a polygraphic study – night registration of the electrical potentials of the body, including from 2 to 8 positions: ECG, nasal respiratory flow, thoracic and abdominal effort, oxygen saturation of arterial blood, muscle activity of the lower extremities, the sound phenomenon of snoring, body position during sleep.
Treatment of sleep apnea
The treatment program may include the use of non-medicinal, medicinal and surgical methods of influencing the cause of the disease. General recommendations for mild night breathing disorders include sleeping with the head end of the bed raised (20 cm higher than usual), excluding sleeping in the back position, instilling xylometazoline (galazoline) into the nose at night to improve nasal breathing, gargling with a solution of essential oils, treatment of pathology of ENT organs (chronic rhinitis, sinusitis), endocrinopathy, exclusion of taking sleeping pills and alcohol, weight loss.
During sleep, it is possible to use various oral devices (lower jaw extenders, tongue restraints) that help maintain the lumen of the respiratory tract, oxygen therapy.
The use of overmasking hardware CPAP therapy (CPAP ventilation), which ensures the maintenance of a constant positive pressure of the airways, allows to normalize night breathing and improve the daytime well–being of patients with sleep apnea. This method is currently considered the most promising and effective. Prescribing theophylline does not always give the desired effect in patients with obstructive sleep apnea. With the central form of sleep apnea, a positive effect from taking acetazolamide is possible.
Surgical interventions for sleep apnea are considered as auxiliary in cases of existing anomalies and defects in the structure of the upper respiratory tract or their chronic diseases. In some cases, adenoidectomy, correction of the nasal septum and tonsillectomy can completely eliminate the causes of sleep apnea. Uvulopalatopharyngoplasty and tracheostomy operations are performed in extremely severe disorders.
Prognosis and prevention
Sleep apnea is far from a harmless disorder. The increase in clinical symptoms occurs over time and can cause severe disability or death in 40% of patients in the first 5 years of the disease, in 50% – over the next 5 years and in 94% of patients with 15 years of experience of the disease.
Mortality rates in patients with sleep apnea are 4.5 times higher than those in the general population. The use of CPAP therapy has reduced the mortality rate by 48% and increased life expectancy by 15 years. However, this method has no effect on the pathogenesis of sleep apnea.
Prevention of possible complications of sleep apnea dictates the need for the participation of specialists in the treatment of the syndrome of pulmonologists, otolaryngologists, cardiologists, neurologists. In the case of sleep apnea, we can only talk about non-specific prevention, including weight normalization, smoking cessation, taking sleeping pills, alcohol, and treatment of nasopharyngeal diseases.
Literature
- Sleep apnea syndromes and cardiovascular disease. Bounhoure JP, Galinier M, Didier A, Leophonte P. Bull Acad Natl Med. 2005 Mar;189(3):445-59; discussion 460-4. link
- Sleep apnea-hypopnea syndromes and heart failure. Arias MA, García-Río F, Alonso-Fernández A, Sánchez AM. Rev Esp Cardiol. 2007 Apr;60(4):415-27. link
- Sleep apnea and the heart: diagnosis and treatment. Yumino D, Kasanuki H. Rev Cardiovasc Med. 2008 Summer;9(3):159-67. link
- Sleep-disordered breathing: implications for the pathophysiology and management of cardiovascular disease. Nelson CA, Wolk R, Somers VK. Compr Ther. 2005 Spring;31(1):21-7 link
- Sleep-disordered breathing and the association with cardiovascular risk. Merritt SL. Prog Cardiovasc Nurs. 2004 Winter;19(1):19-27. link