and undersea medicine for the
non-medical diver, the
physician and the specialist.
What is it?
Nitrogen narcosis is an effect on
brain of gaseous nitrogen that occurs to divers who go
100 FSW, due to the laws of partial pressures.
Nitrogen is an inert
gas existing in largest quantity in the atmosphere,
in air. It is inert, meaning that it does not take part in
It is the gas that causes nitrogen narcosis through the
Dalton's and Henry's laws and it is the gas that causes
sickness on ascent from
depth with reduction of pressure, (Boyle's Law). Nitrogen is
determines decompression schedules.
What are some of the
Complex reasoning decreases 33%
dexterity decreases 7.3%. The condition causes loss of motor
decision making ability and can be more clearly defined as
to become "drunk", as with alcoholic beverages. The
had "three Martinis" is apt, and it has been stated that one
the narcotic effect of one Martini for every 50 feet of sea
What are Dalton's and Henry's Laws?
Dalton's Law states that the
exerted by a mixture of gases is equal to the sum
pressure of each of the different gases making up the
each gas acting as if it alone was present and
volume. This same law causes oxygen toxicity and enhances
the role of
gases such as carbon monoxide and hydrocarbons.
pN2 + p other gases
fN2 x ATA
Henry's law states that, in a fluid the volume of a gas is
proportional to the pressure above the fluid, or the partial
of the gas to which the fluid is exposed.
How does nitrogen
the nervous system?
There is a critical volume
that states there to be an increased volume of nitrogen in
and this relates to solubility. This explains the pressure
Nitrogen narcosis is potentiated by
increased CO2 levels.
can it be prevented?
Avoid deep diving below 100 feet
Certain factors increase the possibility of nitrogen
- Heavy work and fatigue
- CO2 retention
How is nitrogen narcosis
Treatment of nitrogen narcosis is
controlled ascent to the surface, with the buddy or
the diver for unusual behavior, administration of O2 and
of diving. Prevention should be the best treatment, with no
below 100 feet.
of Harm possible - Drowning would be
the worst case scenario.
of Harmful Outcome. The likelihood of a serious
upon numerous factors we are unable to predict.
Given the usual
recreational diving situation a harmful outcome is
factors, Avoidable? Yes [see modifiers above]
it Worth It? Yes. The risk of nitrogen narcosis is
far overweighed by
personal advantages of recreational scuba diving.
This is a personal