Factors associated with residual symptoms after recompression in type I decompression sickness

Abstract

Purpose: The aim of this study is to investigate factors associated with residual symptoms after hyperbaric oxygen therapy (HBOT) in type I decompression sickness (DCS).

Basic procedures: An HBOT registry, which includes patients with type I DCS, was analyzed retrospectively. We divided enrolled patients into two groups; complete resolution group and residual symptom (RS) group after a single HBOT session. We investigated factors associated with residual symptoms at discharge with univariable and multivariable analyses. Restrictive cubic spline curve and a test for trend analysis were used to show the trend of therapeutic response after HBOT based on time from symptom onset to HBOT.

Main findings: In a total of 195 patients, 131 (67.2%) patients were included in the RS group after single HBOT. Prolonged time from symptom onset to recompression was independently associated with residual symptoms (P = .004). When patients who underwent recompression within 24 hours from symptom were included in the reference group, the adjusted odds ratios (AOR) (95% confidence interval) of residual symptoms after HBOT were the following: 24 to 96 hours, 2.24 (0.75-6.65); 96 to 240 hours, 3.31 (1.08-10.13); more than 240 hours, 22.83 (2.45-231.43). In terms of sort of diving, commercial and recreational divers had higher probability of residual symptoms than military divers (AOR, 4.78 and 33.36, respectively).

Principal conclusions: Early HBOT is associated with rapid symptom elimination after treatment in type I DCS. Military divers showed a more immediate response after recompression in comparison with commercial and recreational divers.