Bubble formation in crustaceans following decompression from hyperbaric gas exposures.

In vivo bubble formation was studied in various crustaceans equilibrated with high gas pressures and rapidly decompressed to atmospheric pressure. The species varied widely in susceptibility to bubble formation, and adults were generally more susceptible than larval stages. Bubbles did not form in early brine shrimp larvae unless equilibration pressures of at least 175 atm argon or 350 atm helium were used; for adult brine shrimp, copepods, and the larvae of crabs and shrimps, 100-125 atm argon or 175-225 atm helium were required. In contrast, bubbles formed in the leg joints of megalopa and adult crabs following decompression from only 3-10 atm argon; stimulation of limb movements increased this bubble formation, whereas inhibition of movements decreased it. High hydrostatic compressions applied before gas equilibration or slow compressions did not affect bubble formation. We concluded that circulatory systems, musculature, and storage lipids do not necessarily render organisms susceptible to bubble formation and that bubbles do not generally originate as preformed nuclei. In some cases, tribonucleation appears to be the cause of the bubbles.