Risk factors and clinical outcome in military divers with neurological decompression sickness: influence of time to recompression.

BACKGROUND: This study was designed to examine the influence of short delay to recompression and other risk factors associated with the development of severe neurological decompression sickness (DCS) in military divers.

METHODS: Fifty-nine divers with DCS treated in less than 6 hours from onset of symptoms to hyperbaric recompression were included retrospectively. Diving parameters, symptom latency and recompression delay were analysed. Clinical symptoms were evaluated for both the acute event and one month later.

RESULTS: Median delay to hyperbaric treatment was 35 min (2-350 min). Resolution was incomplete after one month in 25.4 % of divers with DCS. Multivariate analysis demonstrated that severe symptoms, classified as sensory and motor deficits or the presence of bladder dysfunction, were predictors of poor recovery with adjusted odds ratios (OR) of 4.1 (1.12 to 14.92) and 9.99 (1.5 to 66.34) respectively. There was a relationship between a longer delay to treatment and incomplete recovery, but the increased risk appeared negligible with an adjusted OR of 1.01 (1-1.02).

CONCLUSION: Our results suggest that neurological severity upon occurrence is the main independent risk factor associated with a poor outcome in military divers with DCS. Clinical recovery was not dramatically improved in this series when recompression treatment was performed promptly.