Int J Sports Med 2014; 35(06): 465-468
DOI: 10.1055/s-0033-1334968
Physiology & Biochemistry
© Georg Thieme Verlag KG Stuttgart · New York

Influence of Repeated Daily Diving on Decompression Stress

J. Zanchi
1  Cardiology, University Hospital Split, Split, Croatia
,
M. Ljubkovic
2  Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
,
P. J. Denoble
3  Medical Research, Divers Alert Network, Durham, United States
,
Z. Dujic
2  Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
,
S. Ranapurwala
3  Medical Research, Divers Alert Network, Durham, United States
4  Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
,
N. W. Pollock
3  Medical Research, Divers Alert Network, Durham, United States
› Author Affiliations
Further Information

Publication History



accepted after revision 05 February 2013

Publication Date:
14 June 2013 (eFirst)

Abstract

Acclimatization (an adaptive change in response to repeated environmental exposure) to diving could reduce decompression stress. A decrease in post-dive circulating venous gas emboli (VGE or bubbles) would represent positive acclimatization. The purpose of this study was to determine whether four days of daily diving alter post-dive bubble grades. 16 male divers performed identical no-decompression air dives on 4 consecutive days to 18 meters of sea water for 47 min bottom times. VGE monitoring was performed with transthoracic echocardiography every 20 min for 120 min post-dive. Completion of identical daily dives resulted in progressively decreasing odds (or logit risk) of having relatively higher grade bubbles on consecutive days. The odds on Day 4 were half that of Day 1 (OR 0.50, 95% CI: 0.34, 0.73). The odds ratio for a >III bubble grade on Day 4 was 0.37 (95% CI: 0.20, 0.70) when compared to Day 1. The current study indicates that repetitive daily diving may reduce bubble formation, representing a positive (protective) acclimatization to diving. Further work is required to evaluate the impact of additional days of diving and multiple dive days and to determine if the effect is sufficient to alter the absolute risk of decompression sickness.