Decreased Incidence of Pulmonary Barotrauma After Discontinuation of Emergency Free Ascent Training

Abstract

INTRODUCTION: Because a significant association between training to perform emergency free ascent (EFA) and the occurrence of pulmonary barotrauma (PBT) was demonstrated in 2006, the Belgian Underwater Federation (BUF) decided to discontinue this procedure. An evaluation was needed 10 yr after the implementation of this change. METHODS: All medical records with a diagnosis of PBT that occurred in Belgium from November 2006 to September 2016 were prospectively collected. Data on the proportion of in-water skills training dives were obtained from BUF. RESULTS: A total of 5 cases of PBT were identified, significantly down from 34 cases in the previous 10-yr period. Of those cases, four occurred during training dives (two during ascent training). Analysis of the case files furthermore showed that two should have been medically disqualified from diving. Compared with the retrospective cohort (1995-2005), incidences are significantly reduced from 0.83 to 0.078/10,000 training dives and from 3.33 to 0.11/10,000 ascent-training dives; concomitantly, the incidence of PBT in nontraining dives also was reduced (from 0.0042 to 0.0014x10-4/10,000 dives), possibly because less divers undertake the EFA procedure in case of a technical incident and have learned to solve the problem differently. DISCUSSION: Discontinuation of emergency free ascent training was associated with a reduction in the incidence of PBT in the 10-yr follow-up period. We observed a significant decrease of PBT during training dives, confirming the hypothesis that EFA training in its previous form did not contribute significantly to diving safety.Lafere P, Germonpre P, Guerrero F, Marroni A, Balestra C. Decreased incidence of pulmonary barotrauma after discontinuation of emergency free ascent training.