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applies to the expansion and contraction of gases
within the body due to external pressure changes:
If the pressure starts out as one atmosphere at
the surface, it increases linearly with depth under water depending
upon the density of the water:
PATA = 1 + (depth/kappa)
where kappa depends on the density of the water and units of depth:
states that in a mixture of n gases the partial pressure of
each gas [Pi] is proportional to the molar fraction of each gas
[Yi] that makes up the total:
||Value of kappa
||Depth in feet
||Depth in meters
PTotal = P1 + P2 + ... + Pn
= Y1PTotal + Y2PTotal + ... + YnPTotal
Dalton's Law can be used to determine how much nitrogen, oxygen, or carbon dioxide is in
the ambient air at any hyperbaric pressure underwater.
states a gas will dissolve into a liquid in proportion
to its partial pressure in the air and its solubility in the
Ci in solution = Si × Pi
Henry's Law can predict the body's absorption of inert gases into and
back from the body at any pressure or depth.
where Si = solubility coefficient of gas i in a given solute, cc/mL/atm.
severity of nitrogen narcosis symptoms with depth in feet and pressures in
||Reasoning measurably slowed.
||Joviality; reflexes slowed; idea fixation.
||Euphoria; impaired concentration; drowsiness.
||Mental confusion; inaccurate observations.
||Stupefaction; loss of perceptual faculties.
|Symptoms and terminology
|Location of Bubbles
||Pain upon flexure.
||Altered skin sensation, itching, or rash.
||Dizziness, headache, loss of coordination, weakness.
||Cough, dyspnea, pain upon breathing.