Effects on Serum Constituents and Urinary Metabolite Excretion of Repeated Compressed Air Dives

摘要

Eighteen qualified U.S. Navy divers underwent either of two series of dives to 6.7 ATA for 45-50 minutes in compressed air in a dry chamber: 4 dives at 3-day intervals or 5 dives performed daily. Serum and urinary components were monitored before and after the dives to compare the biologic influence of repeated diving with the known effects of hyperbaric saturation exposures. No diuresis or changes in glomerular filtration rate were demonstrated to result from the repeated sequences of pressurization and decompression. Biochemical evidence supports the previous finding of a hemodilution resulting from repeated short-term pressure exposures. The increasing extent of metabolic changes during the first few dives leads to the conclusion that adaptation to repeated dives may begin to play a role after two or three dives particularly when performed at three-day intervals. While no cumulative effects beyond those associated with 2-3 dives are apparent when dives are performed with a few days intervening, limited biologic changes occur when dives are performed daily and seem to require an extended recovery period to allow metabolic processes to return to a state of predive equilibrium. (Author)