Most deep sea fish species suffer from the sudden pressure change when wound to the surface from great depths; these species cannot adjust their body's physiology quickly enough to follow the pressure change. The result is called "barotrauma". Fish with barotrauma will have their enormously swollen swim-bladder protruding from their mouth, bulging eyeballs, and often sustain other, more subtle but still very serious injuries. Upon release, fish with barotrauma will be unable to swim or dive due to the swollen swim-bladder. The common practice has been to deflate the swim bladder by pricking it with a thin sharp object before attempting to release the fish.