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Hub AI
Apnea AI simulator
(@Apnea_simulator)
Hub AI
Apnea AI simulator
(@Apnea_simulator)
Apnea
Apnea (also spelled apnoea in British English) is the temporary cessation of breathing. During apnea, there is no movement of the muscles of inhalation,[citation needed] and the volume of the lungs initially remains unchanged. Depending on how blocked the airways are (patency), there may or may not be a flow of gas between the lungs and the environment. If there is sufficient flow, gas exchange within the lungs and cellular respiration would not be severely affected. Voluntarily doing this is called holding one's breath. Apnea may first be diagnosed in childhood, and it is recommended to consult an ENT specialist, allergist or sleep physician to discuss symptoms when noticed; malformation and/or malfunctioning of the upper airways may be observed by an orthodontist.
Apnea can be involuntary—for example, drug-induced (such as by opiate toxicity), mechanically / physiologically induced (for example, by strangulation or choking), or a consequence of neurological disease or trauma. During sleep, people with severe sleep apnea can have over thirty episodes of intermittent apnea per hour every night.
Apnea can also be observed during periods of heightened emotion, such as during crying or accompanied by the Valsalva maneuver when a person laughs. Apnea is a common feature of sobbing while crying, characterized by slow but deep and erratic breathing followed by brief periods of breath holding.
Another example of apnea are breath-holding spells; these are sometimes emotional in cause and are usually observed in children as a result of frustration, emotional stress and other psychological extremes.
Voluntary apnea can be achieved by closing the vocal cords, simultaneously keeping the mouth closed and blocking the nasal vestibule, or constantly activating expiratory muscles, not allowing any inspiration.
Under normal conditions, humans cannot store much oxygen in the body. Prolonged apnea leads to severe lack of oxygen in the blood circulation, leading to dysfunction of organ systems. Permanent brain damage can occur after as little as three minutes and death will inevitably ensue after a few more minutes unless ventilation is restored. However, under special circumstances such as hypothermia, hyperbaric oxygenation, apneic oxygenation (see below), or extracorporeal membrane oxygenation, much longer periods of apnea may be tolerated without severe detrimental consequences.
Untrained humans usually cannot sustain voluntary apnea for more than one or two minutes, since the urge to breathe becomes unbearable.[citation needed] The reason for the time limit of voluntary apnea is that the rate of breathing and the volume of each breath are tightly regulated to maintain constant values of CO2 tension and pH of the blood more than oxygen levels. In apnea, CO2 is not removed through the lungs and accumulates in the blood. The consequent rise in CO2 tension and drop in pH result in stimulation of the respiratory centre in the brain which eventually cannot be overcome voluntarily. The accumulation of carbon dioxide in the lungs will eventually irritate and trigger impulses from the respiratory center part of the brain and the phrenic nerve. Rising levels of carbon dioxide signal the body to breathe and resume unconscious respiration forcibly. The lungs start to feel as if they are burning, and the signals the body receives from the brain when CO2 levels are too high include strong, painful, and involuntary contractions or spasms of the diaphragm and the muscles in between the ribs. At some point, the spasms become so frequent, intense and unbearable that continued holding of the breath is nearly impossible.[citation needed]
When a person is immersed in water, physiological changes due to the mammalian diving reflex enable somewhat longer tolerance of apnea even in untrained persons as breathing is not possible underwater. Tolerance can in addition be trained. The ancient technique of free-diving requires breath-holding, and world-class free-divers can hold their breath underwater up to depths of 214 metres (702 ft) and for more than four minutes. Apneists, in this context, are people who can hold their breath for a long time.
Apnea
Apnea (also spelled apnoea in British English) is the temporary cessation of breathing. During apnea, there is no movement of the muscles of inhalation,[citation needed] and the volume of the lungs initially remains unchanged. Depending on how blocked the airways are (patency), there may or may not be a flow of gas between the lungs and the environment. If there is sufficient flow, gas exchange within the lungs and cellular respiration would not be severely affected. Voluntarily doing this is called holding one's breath. Apnea may first be diagnosed in childhood, and it is recommended to consult an ENT specialist, allergist or sleep physician to discuss symptoms when noticed; malformation and/or malfunctioning of the upper airways may be observed by an orthodontist.
Apnea can be involuntary—for example, drug-induced (such as by opiate toxicity), mechanically / physiologically induced (for example, by strangulation or choking), or a consequence of neurological disease or trauma. During sleep, people with severe sleep apnea can have over thirty episodes of intermittent apnea per hour every night.
Apnea can also be observed during periods of heightened emotion, such as during crying or accompanied by the Valsalva maneuver when a person laughs. Apnea is a common feature of sobbing while crying, characterized by slow but deep and erratic breathing followed by brief periods of breath holding.
Another example of apnea are breath-holding spells; these are sometimes emotional in cause and are usually observed in children as a result of frustration, emotional stress and other psychological extremes.
Voluntary apnea can be achieved by closing the vocal cords, simultaneously keeping the mouth closed and blocking the nasal vestibule, or constantly activating expiratory muscles, not allowing any inspiration.
Under normal conditions, humans cannot store much oxygen in the body. Prolonged apnea leads to severe lack of oxygen in the blood circulation, leading to dysfunction of organ systems. Permanent brain damage can occur after as little as three minutes and death will inevitably ensue after a few more minutes unless ventilation is restored. However, under special circumstances such as hypothermia, hyperbaric oxygenation, apneic oxygenation (see below), or extracorporeal membrane oxygenation, much longer periods of apnea may be tolerated without severe detrimental consequences.
Untrained humans usually cannot sustain voluntary apnea for more than one or two minutes, since the urge to breathe becomes unbearable.[citation needed] The reason for the time limit of voluntary apnea is that the rate of breathing and the volume of each breath are tightly regulated to maintain constant values of CO2 tension and pH of the blood more than oxygen levels. In apnea, CO2 is not removed through the lungs and accumulates in the blood. The consequent rise in CO2 tension and drop in pH result in stimulation of the respiratory centre in the brain which eventually cannot be overcome voluntarily. The accumulation of carbon dioxide in the lungs will eventually irritate and trigger impulses from the respiratory center part of the brain and the phrenic nerve. Rising levels of carbon dioxide signal the body to breathe and resume unconscious respiration forcibly. The lungs start to feel as if they are burning, and the signals the body receives from the brain when CO2 levels are too high include strong, painful, and involuntary contractions or spasms of the diaphragm and the muscles in between the ribs. At some point, the spasms become so frequent, intense and unbearable that continued holding of the breath is nearly impossible.[citation needed]
When a person is immersed in water, physiological changes due to the mammalian diving reflex enable somewhat longer tolerance of apnea even in untrained persons as breathing is not possible underwater. Tolerance can in addition be trained. The ancient technique of free-diving requires breath-holding, and world-class free-divers can hold their breath underwater up to depths of 214 metres (702 ft) and for more than four minutes. Apneists, in this context, are people who can hold their breath for a long time.