"Decompression sickness Decompression sickness (DCS; also known as divers' disease, the bends, aerobullosis, or caisson disease) describes a condition arising from dissolved gases coming out of solution into bubbles inside the body on depressurisation. DCS most commonly refers to problems arising from underwater diving decompression (i.e., during ascent), but may be experienced in other depressurisation events such as emerging from a caisson, flying in an unpressurised aircraft at altitude, and extravehicular activity from spacecraft. DCS and arterial gas embolism are collectively referred to as decompression illness. Since bubbles can form in or migrate to any part of the body, DCS"
"Decompression illness Decompression Illness (DCI) describes a range of symptoms arising from decompression of the body. DCI can be caused by two different mechanisms, which result in overlapping sets of symptoms. The two mechanisms are: In any situation that could cause decompression sickness, there is also potentially a risk of arterial gas embolism, and as many of the symptoms are common to both conditions, it may be difficult to distinguish between the two in the field, and first aid treatment is the same for both mechanisms. Below is a summary comparison of the signs and symptoms of DCI arising from"
"is not decompression sickness but altitude sickness, or acute mountain sickness (AMS), which has an entirely different and unrelated set of causes and symptoms. AMS results not from the formation of bubbles from dissolved gasses in the body but from exposure to a low partial pressure of oxygen and alkalosis. However, passengers in unpressurized aircraft at high altitude may also be at some risk of DCS. Altitude DCS became a problem in the 1930s with the development of high-altitude balloon and aircraft flights but not as great a problem as AMS, which drove the development of pressurized cabins, which coincidentally"
"Therapeutic recompression is a medical procedure for treatment of decompression sickness, and is followed by decompression, usually to a relatively conservative schedule. Equipment directly associated with decompression includes: The symptoms of decompression sickness are caused by damage from the formation and growth of bubbles of inert gas within the tissues and by blockage of arterial blood supply to tissues by gas bubbles and other emboli consequential to bubble formation and tissue damage. The precise mechanisms of bubble formation and the damage they cause has been the subject of medical research for a considerable time and several hypotheses have been advanced"
"decompression sickness (also known as ""the bends""). Nitrox is used to a lesser extent in surface-supplied diving, as these advantages are reduced by the more complex logistical requirements for nitrox compared to the use of simple low-pressure compressors for breathing gas supply. Nitrox can also be used in hyperbaric treatment of decompression illness, usually at pressures where pure oxygen would be hazardous. Nitrox is not a safer gas than compressed air in all respects; although its use can reduce the risk of decompression sickness, it increases the risk of oxygen toxicity and fire. Though not generally referred to as nitrox,"
"its two components: ""Decompression Sickness"" and ""Arterial Gas Embolism"". Many signs and symptoms are common to both maladies, and it may be difficult to diagnose the actual problem. The dive history can be useful to distinguish which is more probable, but it is possible for both components to manifest at the same time following some dive profiles. First aid is common for both DCS and AGE: Treatment for the ""Decompression Sickness"" and the ""Arterial Gas Embolism"" components of DCI may differ significantly. Refer to the separate treatments under those articles. Decompression illness Decompression Illness (DCI) describes a range of symptoms"
"partial pressure, in order to let their body tissues outgas nitrogen slowly enough that bubbles are not formed. When the astronaut returns to the ""shirt sleeve"" environment of the spacecraft after an EVA, pressure is restored to whatever the operating pressure of that spacecraft may be, generally normal atmospheric pressure. Decompression illness in spaceflight consists of decompression sickness (DCS) and other injuries due to uncompensated changes in pressure, or barotrauma. Decompression sickness is the injury to the tissues of the body resulting from the presence of nitrogen bubbles in the tissues and blood. This occurs due to a rapid reduction"
"Saturation decompression is a physiological process of transition from a steady state of full saturation with inert gas at raised pressure to standard conditions at normal surface atmospheric pressure. It is a long process during which inert gases are eliminated at a very low rate limited by the slowest affected tissues, and a deviation can cause the formation of gas bubbles which can produce decompression sickness. Most operational procedures rely on experimentally derived parameters describing a continuous slow decompression rate, which may depend on depth and gas mixture. In saturation diving all tissues are considered saturated and decompression which is"
"from asphyxiation, but in later experiments, signs of what was later to become known as decompression sickness were observed. Later, when technological advances allowed the use of pressurisation of mines and caissons to exclude water ingress, miners were observed to present symptoms of what would become known as caisson disease, the bends, and decompression sickness. Once it was recognized that the symptoms were caused by gas bubbles, and that recompression could relieve the symptoms, further work showed that it was possible to avoid symptoms by slow decompression, and subsequently various theoretical models have been derived to predict low-risk decompression profiles"
"cm of water or more. Vertigo is recorded as a symptom of decompression sickness in 5.3% of cases by the US Navy as reported by Powell, 2008 It including isobaric decompression sickness. Decompression sickness can also be caused at a constant ambient pressure when switching between gas mixtures containing different proportions of inert gas. This is known as isobaric counterdiffusion, and presents a problem for very deep dives. For example, after using a very helium-rich trimix at the deepest part of the dive, a diver will switch to mixtures containing progressively less helium and more oxygen and nitrogen during the"
"Decompression theory Decompression theory is the study and modelling of the transfer of the inert gas component of breathing gases from the gas in the lungs to the tissues and back during exposure to variations in ambient pressure. In the case of underwater diving and compressed air work, this mostly involves ambient pressures greater than the local surface pressure, but astronauts, high altitude mountaineers, and travellers in aircraft which are not pressurised to sea level pressure, are generally exposed to ambient pressures less than standard sea level atmospheric pressure. In all cases, the symptoms caused by decompression occur during or"
"sickness, or ""the bends"". This problem may be managed by decompressing slowly enough to allow the gas to be eliminated while still dissolved, and eliminating those bubbles which do form while they are still small and few enough not to produce symptoms. The physiology of decompression involves a complex interaction of gas solubility, partial pressures and concentration gradients, diffusion, bulk transport and bubble mechanics in living tissues. Gas is breathed at ambient pressure, and some of this gas dissolves into the blood and other fluids. Inert gas continues to be taken up until the gas dissolved in the tissues is"
"Decompensation In medicine, decompensation is the functional deterioration of a structure or system that had been previously working with the help of allostatic compensation. Decompensation may occur due to fatigue, stress, illness, or old age. When a system is ""compensated"", it is able to function despite stressors or defects. Decompensation describes an inability to compensate for these deficiencies. It is a general term commonly used in medicine to describe a variety of situations. For example, ""cardiac decompensation"" may refer to the failure of the heart to maintain adequate blood circulation, after long-standing (previously compensated) vascular disease (see heart failure). Short-term"
"if fresh air from the surface was continually forced under pressure into the bell. By the 19th century, caissons were regularly used in civil construction, but workers experienced serious, sometimes fatal, symptoms on returning to the surface, a syndrome called caisson disease or decompression sickness. Many workers were killed by the disease on projects such as the Brooklyn Bridge and the Eads Bridge and it was not until the 1890s that it was understood that workers had to decompress slowly, to prevent the formation of dangerous bubbles in tissues. Air under moderately high pressure, such as is used when diving"
"As a result, groups such as Divers Alert Network (DAN) offer medical insurance policies that specifically cover all aspects of treatment for decompression sickness at rates of less than $100 per year. In the United Kingdom, treatment of DCS is provided by the National Health Service. This may occur either at a specialised facility or at a hyperbaric centre based within a general hospital. Animals may also contract DCS, especially those caught in nets and rapidly brought to the surface. It has been documented in loggerhead turtles and likely in prehistoric marine animals as well. Modern reptiles are susceptible to"
"modelling of the transfer of the inert gas component of breathing gases from the gas in the lungs to the tissues of the diver and back during exposure to variations in ambient pressure. In the case of underwater diving and compressed air work, this mostly involves ambient pressures greater than the local surface pressure—but astronauts, high altitude mountaineers, and occupants of unpressurized aircraft, are exposed to ambient pressures less than standard sea level atmospheric pressure. In all cases, the symptoms of decompression sickness occur during or within a relatively short period of hours, or occasionally days, after a significant reduction"
"the symptoms known as decompression sickness, and also delays the elimination of the gas. Decompression modeling attempts to explain and predict the mechanism of gas elimination and bubble formation within the organism during and after changes in ambient pressure, and provides mathematical models which attempt to predict acceptably low risk and reasonably practicable procedures for decompression in the field. Both deterministic and probabilistic models have been used, and are still in use. Gas is breathed at ambient pressure, and some of this gas dissolves into the blood and other fluids. Inert gas continues to be taken up until the gas"
"at or less than 116 fsw. Use: Treatment of decompression sickness where relief is obtained at or less than 166 fsw. Use: Treatment of decompression sickness where relief is obtained at or less than 216 fsw. Use: Treatment of decompression sickness where relief is obtained at or less than 266 fsw. Use: Treatment of moderate to severe decompression sickness when oxygen is not available or the patient cannot tolerate the elevated oxygen partial pressure. Use: Treatment of moderate to severe decompression sickness when oxygen is available. Use: Treatment of mild decompression sickness when oxygen is not available or the patient"
"is a procedure for treating decompression sickness by recompressing the diver, thus reducing bubble size, and allowing the gas bubbles to re-dissolve, then decompressing slowly enough to avoid further formation or growth of bubbles, or eliminating the inert gases by breathing oxygen under pressure. Recompression on atmospheric air was shown to be an effective treatment for minor DCS symptoms by Keays in 1909. Historically, therapeutic decompression was done by recompressing the diver to the depth of relief of pain, or a bit deeper, maintaining that pressure for a while, so that bubbles could be re-dissolved, and performing a slow decompression"
"their normal amount of dissolved gas. But if they move quickly to a lower ambient pressure, then the gas comes out of our blood and tissues violently, in large bubbles, in the same way that quickly removing the cap from a bottle of soft drink produces far more bubbles than slowly opening the bottle. Different types of illness result from increases in pressure (for example, descent during an underwater dive, descent during a plane flight), versus decreases in pressure (for example, coming up from a caisson, or ascending a mountain). Dysbarism comprises several types of illness: Decompression sickness, also called"
"(such as the central nervous system) are involved. Type II DCS is considered more serious and usually has worse outcomes. This system, with minor modifications, may still be used today. Following changes to treatment methods, this classification is now much less useful in diagnosis, since neurological symptoms may develop after the initial presentation, and both Type I and Type II DCS have the same initial management. The term dysbarism encompasses decompression sickness, arterial gas embolism, and barotrauma, whereas decompression sickness and arterial gas embolism are commonly classified together as decompression illness when a precise diagnosis cannot be made. DCS and"
"Mal de debarquement Mal de debarquement (or mal de débarquement) syndrome (MdDS, or common name disembarkment syndrome) is a neurological condition usually occurring after a cruise, aircraft flight, or other sustained motion event. The phrase ""mal de débarquement"" is French and translates to ""illness of disembarkation"". MdDS is typically diagnosed by a neurologist or an ear nose & throat specialist when a person reports a persistent rocking, swaying, or bobbing feeling (though they are not necessarily rocking). This usually follows a cruise or other motion experience. Because most vestibular testing proves to be negative, doctors may be baffled as they"
"decompression sickness is rare, estimated at 2.8 cases per 10,000 dives, with the risk 2.6 times greater for males than females. DCS affects approximately 1,000 U.S. scuba divers per year. In 1999, the Divers Alert Network (DAN) created ""Project Dive Exploration"" to collect data on dive profiles and incidents. From 1998 to 2002, they recorded 50,150 dives, from which 28 recompressions were required — although these will almost certainly contain incidents of arterial gas embolism (AGE) — a rate of about 0.05%. Around 2013, Honduras had the highest number of decompression-related deaths and disabilities in the world, caused by unsafe"
"functions such as decision-making and planning become impaired. Parkinson's disease (PD), also known as ""Parkinson disease"", is a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills and speech. Parkinson's disease belongs to a group of conditions called movement disorders. It is characterized by muscle rigidity, tremor, a slowing of physical movement (bradykinesia), and in extreme cases, a loss of physical movement (akinesia). The primary symptoms are the results of decreased stimulation of the motor cortex by the basal ganglia, normally caused by the insufficient formation and action of dopamine, which is produced in the"
"Use: Treatment of mild decompression sickness where relief occurs within 30 minutes at 30 msw (98 fsw) Use: Treatment of mild decompression sickness where relief does not occur within 30 minutes at 30 msw (98 fsw) Use: Treatment of severe decompression sickness where relief does not occur within 30 minutes at 30 msw (98 fsw) 100% oxygen for 30 minutes at 3.0 ATA followed by 60 minutes at 2.5 ATA. Indication: In-water recompression (IWR) or underwater oxygen treatment is the emergency treatment of decompression sickness (DCS) by sending the diver back underwater to allow the gas bubbles in the tissues,"
"lessen the pressure reduction, and hence the risk of DCS. All cases of decompression sickness should be treated initially with 100% oxygen until hyperbaric oxygen therapy (100% oxygen delivered in a high-pressure chamber) can be provided. Mild cases of the ""bends"" and some skin symptoms may disappear during descent from high altitude; however, it is recommended that these cases still be evaluated. Neurological symptoms, pulmonary symptoms, and mottled or marbled skin lesions should be treated with hyperbaric oxygen therapy if seen within 10 to 14 days of development. Recompression on air was shown to be an effective treatment for minor"
"too slow to prevent the rupture. Rapid decompression can rupture eardrums and sinuses, bruising and blood seep can occur in soft tissues, and shock can cause an increase in oxygen consumption that leads to hypoxia. As a consequence of rapid decompression, oxygen dissolved in the blood empties into the lungs to try to equalize the partial pressure gradient. Once the deoxygenated blood arrives at the brain, humans lose consciousness after a few seconds and die of hypoxia within minutes. Blood and other body fluids boil when the pressure drops below 6.3 kPa, and this condition is called ebullism. The steam"
"to defend against a troubling reality. Decompensation In medicine, decompensation is the functional deterioration of a structure or system that had been previously working with the help of allostatic compensation. Decompensation may occur due to fatigue, stress, illness, or old age. When a system is ""compensated"", it is able to function despite stressors or defects. Decompensation describes an inability to compensate for these deficiencies. It is a general term commonly used in medicine to describe a variety of situations. For example, ""cardiac decompensation"" may refer to the failure of the heart to maintain adequate blood circulation, after long-standing (previously compensated)"
"occurring, a doctor may recommend some tests to determine the overlying cause of the hypoesthesia. These tests include imaging computerized axial tomography and magnetic resonance imaging scans (CT and MRI scans respectively), nerve conduction studies to measure electrical impulses passing through the nerves in search of damage to the nerves, and various reflex tests. An example of a reflex test would be the patellar reflex test. Decompression sickness occurs during rapid ascent, spanning 20 or more feet (typically from underwater). Decompression sickness may express itself in a variety of ways, including hypoesthesia. Hypoesthesia results because of air bubbles that form"
"growth in body tissues is the mechanism of decompression sickness, which occurs when supersaturated dissolved inert gases leave solution as bubbles during decompression. The damage can be due to mechanical deformation of tissues due to bubble growth in situ, or by blocking blood vessels where the bubble has lodged. Arterial gas embolism can occur when a gas bubble is introduced to the circulatory system and it lodges in a blood vessel which is too small for it to pass through under the available pressure difference. This can occur as a result of decompression after hyperbaric exposure, a lung overexpansion injury,"
"bubbles before symptoms of DCS become apparent. Paul K Weathersby, Louis D Homer and Edward T Flynn introduced survival analysis into the study of decompression sickness in 1982. Albert A. Bühlmann published ""Decompression–Decompression sickness"" in 1984. Bühlmann recognized the problems associated with altitude diving, and proposed a method that calculated maximum nitrogen loading in the tissues at a particular ambient pressure by modifying Haldane's allowable supersaturation ratios to increase linearly with depth. In 1984 DCIEM (Defence and Civil Institution of Environmental Medicine, Canada) released No-Decompression and Decompression Tables based on the Kidd/Stubbs serial compartment model and extensive ultrasonic testing, and"
"treatment methods involved returning the diver to pressurised conditions by re-immersion in the water. French physiologist Paul Bert was the first to understand it as decompression sickness. His classical work, ""La Pression barometrique"" (1878), was a comprehensive investigation into the physiological effects of air-pressure, both above and below the normal. He determined that inhaling pressurized air caused the nitrogen to dissolve into the bloodstream; rapid depressurization would then release the nitrogen into its natural gaseous state, forming bubbles that could block the blood circulation and potentially cause paralysis or death. Central nervous system oxygen toxicity was also first described in"
"primarily based on clinical experience. John Scott Haldane's decompression procedures and the associated tables developed in the early 1900s greatly reduced the incidence of decompression sickness, but did not eliminate it entirely. It was, and remains, necessary to treat incidences of decompression sickness. During the building of the Brooklyn Bridge, workers with decompression sickness were recompressed in an iron chamber built for this purpose. They were recompressed to the same pressure they had been exposed to while working, and when the pain was relieved, decompressed slowly to atmospheric pressure. Although recompression and slow decompression were the accepted treatment, there was"