A head down position is thought to be harmful in DCS.Oral hydration is recommended in fully conscious persons, and fluids should ideally be isotonic, without alcohol, carbonation or caffeine, as diving is known to cause dehydration, and rehydration is known to reduce post-dive venous gas emboli.Intravascular rehydration is recommended if suitably competent responders are present. Glucose free isotonic crystalloid solutions are preferred. Case evidence shows that aggressive rehydration can be life-saving in severe cases.If there are no contraindications, a non-steroidal anti-inflammatory drug along with hyperbatic oxygen is likely to improve rate of recovery. Corticosteroids, pentoxyphylline, aspirin, lidocaine and nicergoline have been used in early management of DCS, but there is insufficient evidence on their effectiveness.Divers should be kept comfortably warm, but not overheated, as warm subjects are known to eliminate gas more quickly, but overheating aggravates neurological injury. Delay of recompression
Observational evidence shows that outcomes after recompression are likely to be better after immediate recompression, which is only possible when on-site recompression is possible, although the 2004 workshop on decompression came to the conclusion that for cases with mild symptoms, a delay before recompression is unlikely to cause any worsening of long-term outcomes.In more serious cases recompression should be done as soon as safely possible. There is some evidence that delays longer than six hours result in slower or less complete recovery, and the number of treatments required may be increased.
In the presence of a right-to-left shunt of the heart, such as a patent foramen ovale, venous bubbles may enter the arterial system, resulting in an arterial gas embolism. A similar effect, known as ebullism, may occur during explosive decompression, when water vapour forms bubbles in body fluids due to a dramatic reduction in environmental pressure. Inert gases
The main inert gas in air is nitrogen, but nitrogen is not the only gas that can cause DCS. Breathing gas mixtures such as trimix and heliox include helium, which can also cause decompression sickness. Helium both enters and leaves the body faster than nitrogen, so different decompression schedules are required, but, since helium does not cause narcosis, it is preferred over nitrogen in gas mixtures for deep diving. There is some debate as to the decompression requirements for helium during short-duration dives. Most divers do longer decompressions; however, some groups like the WKPP have been experimenting with the use of shorter decompression times by including deep stops. The balance of evidence as of 2020 does not indicate that deep stops increase decompression efficiency. Any inert gas that is breathed under pressure can form bubbles when the ambient pressure decreases. Very deep dives have been made using hydrogen-oxygen mixtures (hydrox), but controlled decompression is still required to avoid DCS. Isobaric counterdiffusion
DCS 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.