[Clinical characterization and treatment of acute decompression sickness after group repeated dives]

To clinically characterize the divers who suffer from decompression sickness in group after diving, optimize therapeutic treatment settings for grouped patients where the conventional individualized treatment cannot be implemented.

Clinical parameters of patients such as age, professional seniority in dive, labor intensity, diving depth and their symptoms were statistically categorized to identify the factors that correlate with treatment efficacy and recurrence rate. In accordance with the symptoms and the reactions to pressure, 4 treatment programs were applied: Program A, Program B, Program C, Program D.

(1) age, professional seniority, diving depth, length of service, dive frequency were positively correlated with the treatment efficacy (P<0.05, P<0.01), and these parameters together with pain intensity were also positively correlated with recurrence risk (P<0.05, P<0.01), while long latency time of the disease often related with poor therapeutic outcome and high recurrence rate (P<0.01), (2) pain intensity were positively affected by age, diving depth and dive frequency (P<0.05, P<0.01), whereas negatively affected by disease latency time (P<0.01), (3) Four elements in this clinic project, selection of treatment program, length of service, diving depth and disease latency time of patient, were responsible for (or: could account for) 48.0% change of treatment efficacy, (4) Among Programs using different therapeutic pressure, Program D, C and B had better outcomes than Program A (P<0.01, P<0.05). Also, less patients in Program D, C and B suffered from recurrence with relative to Program A (P<0.01, P<0.05), (5) Between Programs adopting same hyperbaric pressure and treatment duration time, Program D was more efficient and fewer recurrent cases were found in it if compared to Program B (P<0.05), (6) In programs with same pressure and duration time settings, Program D was remarkably superior to program C in regard of its treatment efficacy.

In condition with only limited clinic supplies, Program D could be the first choice to provide the hyperbaric oxygen as an ideal group treatment, and it is not very necessary for the clinician to provide individualized therapy. An appropriate extension of stay in hyperbaric chamber may apply to some patients but depending on the clinical symptoms, however, no longer time than 120 min is recommended.