the descent and stay at depth

Last reviewed 01/2018

• descent and the stay at depth
  • at sea level, there is free exchange of gases between the air in the alveoli and the dissolved gases in the blood stream
  • however as the diver descends there is an increase in the amount of gas dissolved in the blood
    • as the diver descends the total pressure of the gases in the alveoli becomes greater than atmospheric and, by Henry's law, the amount of the gases dissolved in the blood and thence in the body tissues becomes greater
  • the effects of different gases on the descent and stay at depth are outlined in the linked items

Notes:

• Henry's Law of Solubility of Gases in a Liquid
  • states that the mass of a slightly soluble but inert gas that dissolves in a given amount of a liquid at a constant temperature is proportional to the partial pressure of that gas above the liquid
  • Mathematically: mn=cnPn
    • where mn is the mass of gas n that dissolves in the liquid, cn is the solubility constant for gas n and Pn is the partial pressure of gas n above the liquid

Reference:

• 1) Edge CJ. Recreational diving medicine.Current Anaesthesia Critical Care 2008; 19 (4): 235-246.