Hyperventilation

Breathing provides gas exchange between the external environment and alveolar air , the composition of which under normal conditions varies in a narrow range. With hyperventilation, the oxygen content increases (by 40-50% of the initial), but with further hyperventilation (about a minute or more), the CO ₂ content in the alveoli decreases significantly, as a result of which the level of carbon dioxide in the blood drops below normal (this condition is called hypocapnia ). Hypocapnia in the lungs with deep breathing shifts the pH to the alkaline side, which changes the activity of enzymes and vitamins. This change in the activity of metabolic regulators disrupts the normal course of metabolic processes and leads to cell death. The following protection mechanisms are available to maintain constancy of CO ₂ in the lungs:

• spasms of the bronchi and blood vessels;
• an increase in the production of cholesterol in the liver as a biological insulator, which compacts cell membranes in the lungs and blood vessels;
• lowering blood pressure (hypotension), inhibiting the removal of CO ₂ from the body.

But spasms of the bronchi and blood vessels reduce the flow of oxygen to the cells of the brain, heart, kidneys and other organs. A decrease in CO ₂ in the blood increases the connection between oxygen and hemoglobin and makes it difficult for oxygen to enter the cells ( Verigo-Bor effect ). A decrease in oxygen supply to the tissue causes oxygen starvation of tissues - hypoxia. Hypoxia, in turn, leads first to loss of consciousness, and then to the death of brain tissue.

Controlled Hyperventilation

Efficient use of the lungs is paramount in diving . To increase the supply of the respiratory mixture before diving, controlled hyperventilation is used - the diver takes several deep and quick breaths-exhalations (in no case allowing hypocapnia ) and dives on the inspiration. Excessive hyperventilation before diving can lead to loss of consciousness at a shallow depth (and thus become uncontrollable).

Uncontrolled hyperventilation

Uncontrolled hyperventilation can occur due to any physical activity and leads to unwanted brain hypoxia. So, it can be when running, cycling, but it is especially dangerous when swimming intensively, because in the latter case, loss of consciousness will lead to drowning.

Hyperventilation Loss Prevention

For most healthy people, the first signs of hypoxia are a faint fog or unconsciousness , a state of anxiety, the absence of bodily sensations, which, through inexperience, may be noticed too late. But with the timely detection of symptoms, it is enough to stop swimming on the surface of the water, roll over on your back and hold your breath on inhalation until carbon dioxide accumulates in the blood and brain tissues.

The use of breathing techniques based on hyperventilation allows you to enter an altered state of consciousness . However, such techniques are intended for occasional use ^[1] .

It occurs with tachypnea (rapid surface breathing) without reducing the tidal volume, while there is an increase in the minute volume of breathing and alveolar ventilation. Distinguish between chronic ( hyperventilation syndrome ) and temporary hyperventilation. There are various causes of hyperventilation, in particular neurological and mental disorders ^[2] . In most cases, the cause is nervous tension. The attack can last for hours, but the usual duration of a hyperventilation attack is 20-30 minutes. One way to interrupt such an attack (and sometimes to prevent it) can be breathing in a paper bag, which allows you to replace the carbon dioxide exhaled by the patient ^[3] .

• Oxygen poisoning
• Holotropic breathing
• Buteyko Method

• Articles for divers -> Hyperventilation
• Dictionary of Natural Sciences. Glossary.ru
• Oxford Dictionary of General Medicine (link unavailable)