Does the time course of bubble evolution explain decompression sickness risk?

Abstract

A probabilistic model of decompression sickness (DCS) risk based on linear-exponential (LE) kinetics has given the best fit of the human air and nitrox DCS database. To test the hypothesis that its success may be due to the formation of a gas phase during decompression, we developed a physiologically based bubble evolution model using a numerical solution of a partial differential equation system. Because of the computational intensity of this method, it could not be used to fully explore our hypothesis. Consequently, we compared the solution with that of a computationally simpler approximation that was previously published by Van Liew and found the two approaches gave similar results. Using the simpler model, assuming bubble densities of 1 and 1,000 bubbles/cm3, we found a tissue time constant of at least 80 min (equivalent to perfusion of 1/80 ml.g-1.min-1) was required to achieve a delay in bubble dissolution comparable to the prolonged risk of DCS predicted by the LE model. We suggest that the persistence of single bubbles in a uniformly perfused homogeneous tissue alone is unlikely to explain persistent DCS risk.

• Authors: R Ball, J Himm, L D Homer, E D Thalmann
• Journal: Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc (Undersea Hyperb Med) Vol. 22 Issue 3 Pg. 263-80 (Sep 1995) ISSN: 1066-2936 [Print] United States
• PMID: 7580767 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Noble Gases

Topics

• Blood Flow Velocity
• Decompression Sickness (blood, etiology, physiopathology)
• Diffusion
• Humans
• Kinetics
• Models, Biological
• Noble Gases (pharmacokinetics)
• Risk Assessment
• Time Factors