Research on the simulated heliox 480 m saturation-493 m excursion dive

Objective To acquire related data of a deep saturation dive which approaches the depth limit in terms of physiology,and to further improve medical service for such dives.Methods A series of simulated heliox saturation dives (saturation depths,65-480 m) were conducted by 9 naval divers.During the experiments,modified diving procedures,intensified medical surveillance measures,targeted medical intervention and performance evaluation were applied to ensure the success of the dive.Results Following research results were obtained:the decompression profile based on the bubble theory was developed and applied in a series of diving experiments ; the superiority of urine metabonomics in full-scale and noninvasive medical detection of divers at high pressure was demonstrated; pharmacological intervention was used to alleviate harmful loads; and effective identification means were established to distinguish pressure susceptible people.Conclusions The research results obtained from this project would enrich and deepen intimate knowledge on hyperbaric physiology and would be a good guidance for better medical supports in deep saturation dives. Key words: Saturation diving;  Saturation decompression;  High pressure nervous syndrome;  Oxidative damage;  Metabonomics;  Pressure susceptible people