First post found on google ref. this subject:
Executive SummaryFish which are quickly removed from deep water often display signs of depressurization.Symptoms include over-inflated swim bladders, hemorrhaging, erratic swimmingbehavior and the inability to submerge when released. Death can result from gasembolisms, internal organ damage or from predation and exposure when unable todescend from the water surface.Recently, a procedure known as "fizzing" has been developed in an attempt to artificiallydeflate gas from a distended swim bladder. The procedure involves puncturing the swimbladder through the musculature of the fish with a sharp instrument such as ahypodermic syringe.Despite the relatively widespread use of this technique, particularly at competitive fishingevents, there is considerable controversy about the relative merits of this procedure.Numerous North American jurisdictions either prohibit or discourage the practice of"fizzing".There is a need for more exhaustive research on the practice of artificial air bladderdeflation and the examination of alternate techniques for the successful release of fishwhich have been angled from deep water.Pending further research and evaluation, the widespread use of "fizzing" should bediscouraged in Ontario.
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S. J. KerrFisheries SectionFish and Wildlife BranchOntario Ministry of Natural ResourcesPeterborough, OntarioNovember, 2001
From NH:
Fizzing of Fish
Summary:
Fish caught and quickly removed from deep water often show signs of depressurization. The most obvious signs of depressurization are an over-inflated swim bladder, erratic swimming behavior, the inability to submerge when released, and/or red on the edges of the tail, dorsal fin, and/or mouth. Death can result from gas embolisms, predation or exposure if fish are unable to re-submerge, or from internal organ damage.
"Fizzing," or artificial swim bladder deflation, is sometimes used in an attempt to increase the survival of fish that show signs of depressurization. The procedure involves puncturing the gas bladder through the musculature of the fish using a sharp object such as a hypodermic needle.
The New Hampshire Fish and Game Department's Position on Fizzing:
There is currently no law prohibiting anglers from fizzing bass in NH. However, based on a review of the available literature on fizzing, the NH Fish and Game Department does not advocate the use of fizzing, pending further evaluation and research.
There are a number of reasons not to fizz bass. During fizzing, there is an increased chance of infection to the fish and the potential to pierce other internal organs. Additionally, although the most obvious sign of rapid depressurization is an over inflated swim bladder, there is also internal damage that occurs to the brain and heart (as a result of gas bubbles in the blood). Damage to the brain and heart is often the cause of death in these fish and fizzing will not correct for this type of injury.
In order to avoid bass mortality due to rapid depressurization, the best practice is to not fish for bass in deep water. If deep waters are fished, fish should be released immediately (paper tournament), as many fish are able to re-submerge when released within 1 to 2 minutes. Additionally, there are other release techniques besides fizzing available for releasing fish caught from deep water; see:
