Advanced Dive Medicine Decompression and Bubble theory

Question 1

At sea level how much tissue is saturated in equilibrium with nitrogen

Answer 1

1 Liter

Question 2

Henry’s Law describes

Answer 2

More inert gas is pushed into our tissues at depth . Absorption. Temperature, Depth, Duration, Work-rate

Question 3

Ascend or return to the surface Henry’s Law

Answer 3

Inert dissolved gas remaining in tissue is pushed out, too fast if you don’t control the ascent causing bubbles.

Question 4

JS Haldene

Answer 4

Published first Deco tables 1908

Question 5

JS Haldene theory of fast tissues

Answer 5

Brain, Kidneys

Question 6

JS Haldene theory of slow tissues

Answer 6

Bone, Cartilage, Adipose (fat)

Question 7

JS Haldene theory of half times

Answer 7

Basis for REV 5 Deco table 12, Now 18 hour requirement with no repet designator

Question 8

Tribonucleation

Answer 8

When bubbles become rapidly separated they become viscous (cavitation) Joints cracking

Question 9

Reynolds Cavitation/Bernoulli priniciple

Answer 9

Liquid encounters an obstruction (heart valves) acts like rapids in a river

Question 10

Seed bubbles

Answer 10

Pre-existing bubbles become bigger

Question 11

De Novo

Answer 11

Latin from nothing - water requires -1400 atm to form vapor bubbles

Question 12

Temperature and off gassing

Answer 12

Too warm gas leaves solution before it can diffuse

Too Cold gas is slow to leave solution and to match ambient pressure

Question 13

Supersaturation

Answer 13

Isobaric Counter diffusion due to switching to lighter breathing gas HE02 vice NO, helium moves into tissues faster than NO moves out

Question 14

Intravascular bubbles

Answer 14

Arterial, Venous, Capillary, Lymphatic

Question 15

Venous Gas Embolism

Answer 15

Intravascular pressure lower, PP of inert gas greater. Decompression on ascent

Question 16

Patent Foramen Ovale PFO

Answer 16

Opening between right and left Atria usually closed when infant takes first breath.

Question 17

Mechanical damage of the bubble effect (AGE)

Answer 17

Bubble obstructs blood flow, distorts tissue and vessels

Question 18

Non Mechanical damage

Answer 18

Strips veins (leaky vessel) , kinin’s release, Edema, Blood thickens

Question 19

Body response to Foreign bubbles Direct/Indirect effects

Answer 19

Platelets for clotting, causing leaking capillaries, edema swelling, capillary obstruction, nerve impingement.