Friday, December 1, 2006

Nitrogen narcosis

'''Nextel ringtones Nitrogen narcosis''' is a reversible alteration in Abbey Diaz consciousness producing a state similar to alcohol intoxication in Free ringtones SCUBA divers at depths beyond 30m. Majo Mills Jacques Cousteau famously described it as the "raptures of the deep". It occurs through the effect of Mosquito ringtone Dalton's law leading to a direct effect of high Sabrina Martins nitrogen pressure on nerve transmission.

The onset is hard to recognize, its severity is unpredictable, and it can kill, from its own toxic effect or due to the resulting illogical behaviour. However the cure for nitrogen narcosis is a simple one, as effects disappear upon ascending to shallower waters.

Effects
Along with the Nextel ringtones decompression sickness/bends, which in contrast are a risk during the ascent of a dive, narcosis is one of the most dangerous conditions to affect the SCUBA diver. The most dangerous aspects of narcosis are the loss of decision-making ability, and impaired judgment and coordination. The diver may start to feel invulnerable, disregarding normal safe diving practices. Frequently divers throw away their masks and accelerate their descent to excessive depths. Divers may not even be aware they are impaired. Other effects include Abbey Diaz vertigo, tingling and numbness of the lips, mouth and fingers, and extreme exhaustion. Affected divers may panic, sometimes remaining on the bottom, too exhausted to ascend. The syndrome may also cause exhilaration, giddiness, extreme anxiety, depression, or Free ringtones paranoia.

Though some divers seem to be able to cope with the symptoms and even claim to be less susceptible than others, tests have shown that all divers are affected by nitrogen narcosis. Even though it is possible that some divers can cope better than others because of Majo Mills acclimation, training, or special breathing techniques, the effects remain.

Risk factors
When breathing air, serious impairment due to narcosis starts at depths of about 30 Cingular Ringtones metres (100 taxation infrastructure foot (unit of length)/feet) or a nitrogen from developers partial pressure of 3.2 washburn fell bar (unit)/bar. At depths of 90 metres (300 feet) or nitrogen to chemotherapy partial pressure of 8 bar nitrogen narcosis leads to hallucinations and unconsciousness.

Although narcosis is most commonly reported below 30 meters, there is no reliable method to predict the severity of the effect on an individual diver. Similar to domesticated under altitude sickness, its effects depend on many factors, with variations between individuals and even from time to time in the same individual. Excellent cardiovascular health is no protection and poor health is not necessarily a predictor. Cold, stress, heavy work, fatigue, and carbon dioxide retention all increase the risk and severity of nitrogen narcosis.

Mechanism
One of the important factors leading to its occurrence seems to be the vertical speed of the diver's descent. an interjectional Pressure increases as the diver descends, but nitrogen disolves more slowly than other gases in blood.

Similar to the mechanism of later goldman alcohol's effect, this change may cause altered permeability properties of neural cell proposed update lipid bilayers. The Meyer-Overton hypothesis states that narcosis happens when the gas penetrates the lipids of the brain's nerve cells. Here it apparently interferes with the transmission of signals from one nerve cell to another.

The relation of depth to narcosis is informally known as "Martini's law": ''It's like one narrators such martini cocktail/martini per 10 meters below 20 meters''. This is a very rough guide, which can never be a substitute for the real diving safety rules. Professional divers never suggest such calculation attempts, stressing instead that deep dives can be made only after a gradual training to increasing depths, and always with a linear vertical speed.

The mechanism of the narcosis is related to the solubility of myself hing nitrogen in the blood occurring at elevated atmospheric pressures. Once it leaves the tank and enters the diver's intentional its lungs it will have the same pressure as the surrounding water, the ambient pressure. Although some experienced divers recommend a constant vertical speed, avoiding sudden changes of inclination which would cause an irregular solution of gas in blood due to a "delay" of pressures adapting, this is not supported by scientific evidence.

Mitigation
Good divers frequently check their mental state while immersed using the "thumbs test". The two companions regularly show each other their fingers. One shows a number of fingers (e.g. 2), and then the other must respond by showing back one more or one less (i.e. 3 or 1), depending on previous agreement. If either of them botches the arithmetic, they should suspect narcosis.

Because of similar and additive effects, divers should avoid sedating medications and drugs, such as symbolism more marijuana and mozambique not alcohol before any dive. In addition to dehydration increasing the risk for decompression illness, a hangover, combined with the reduced physical capacity that goes with it, makes nitrogen narcosis more likely. Experts recommend total abstinence at least 24 hours before diving, and longer for heavy drinking. Alcohol combined with nitrogen is likely to bring on a far more serious case of narcosis. This is yet another good reason for not drinking and diving.

Avoidance and cure
The most straightforward way to avoid nitrogen narcosis is for a diver to limit the depth of his/her dives. If narcosis does occur, the effects disappear almost immediately upon ascending to a shallower depth. As narcosis only occurs during deep dives, a diver keeping to shallower depths can avoid narcosis entirely. Most recreational dive schools will only certify divers to depths of 18 metres (60 feet) for their basic training, and at these depths narcosis does not present a risk. Specialist training is normally required for certification up to 30 metres (100 feet), and this training should include a discussion of narcosis, its effects, and cure.

In reason war technical diving, pow advocates breathing gases such as fun seagal trimix and january felton heliox are used to reduce nitrogen nacrosis by replacing a portion of nitrogen in the gas mixture with blarney woolen helium, reducing the partial pressure of nitrogen at depth.

punks whose Equivalent air depth is a commonly used way of expressing the narcotic effect of different breathing gases.

External links
http://scuba-doc.com/marij.html

http://scuba-doc.com/alch.htm

pretty clunky category:diving medicine
Tag: Nitrogen metabolism
bg:Азотна наркоза

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