Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans?
Introduction Previous studies have highlighted a decreased exhaled nitric oxide concentration (FE NO) in divers after hyperbaric exposure in a dry chamber or following a wet dive. The underlying mechanisms of this decrease remain however unknown. The aim of this study was to quantify the separate ef...
| Main Authors: | , , , , |
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| Format: | Journal Article |
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Elsevier Inc
2014
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| Online Access: | http://hdl.handle.net/20.500.11937/72002 |
| _version_ | 1848762632722448384 |
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| author | Pontier, J. Buzzacott, Peter Nastorg, J. Dinh-Xuan, A. Lambrechts, K. |
| author_facet | Pontier, J. Buzzacott, Peter Nastorg, J. Dinh-Xuan, A. Lambrechts, K. |
| author_sort | Pontier, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Introduction Previous studies have highlighted a decreased exhaled nitric oxide concentration (FE NO) in divers after hyperbaric exposure in a dry chamber or following a wet dive. The underlying mechanisms of this decrease remain however unknown. The aim of this study was to quantify the separate effects of submersion, hyperbaric hyperoxia exposure and decompression-induced bubble formation on FE NO after a wet dive. Methods Healthy experienced divers (n = 31) were assigned to either (i) a group making a scuba-air dive (Air dive), (ii) a group with a shallow oxygen dive protocol (Oxygen dive) or (iii) a group making a deep dive breathing a trimix gas mixture (deep-dive). Bubble signals were graded with the KISS score. Before and after each dive FE NO values were measured using a hand-held electrochemical analyzer. Results There was no change in post-dive values of FE NO values (expressed in ppb = parts per billion) in the Air dive group (15.1 ± 3.6 ppb vs. 14.3 ± 4.7 ppb, n = 9, p = 0.32). There was a significant decrease in post-dive values of FE NO in the Oxygen dive group (15.6 ± 6 ppb vs. 11.7 ± 4.7 ppb, n = 9, p = 0.009). There was an even more pronounced decrease in the deep dive group (16.4 ± 6.6 ppb vs. 9.4 ± 3.5 ppb, n = 13, p < 0.001) and a significant correlation between KISS bubble score >0 (n = 13) and percentage decrease in post-dive FE NO values (r = -0.53, p = 0.03). Discussion Submersion and hyperbaric hyperoxia exposure cannot account entirely for these results suggesting the possibility that, in combination, one effect magnifies the other. A main finding of the present study is a significant relationship between reduction in exhaled NO concentration and dive-induced bubble formation. We postulate that exhaled NO concentration could be a useful index of decompression severity in healthy human divers. © 2014 Published by Elsevier Inc. |
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| format | Journal Article |
| id | curtin-20.500.11937-72002 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:50:39Z |
| publishDate | 2014 |
| publisher | Elsevier Inc |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-720022018-12-13T09:34:50Z Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? Pontier, J. Buzzacott, Peter Nastorg, J. Dinh-Xuan, A. Lambrechts, K. Introduction Previous studies have highlighted a decreased exhaled nitric oxide concentration (FE NO) in divers after hyperbaric exposure in a dry chamber or following a wet dive. The underlying mechanisms of this decrease remain however unknown. The aim of this study was to quantify the separate effects of submersion, hyperbaric hyperoxia exposure and decompression-induced bubble formation on FE NO after a wet dive. Methods Healthy experienced divers (n = 31) were assigned to either (i) a group making a scuba-air dive (Air dive), (ii) a group with a shallow oxygen dive protocol (Oxygen dive) or (iii) a group making a deep dive breathing a trimix gas mixture (deep-dive). Bubble signals were graded with the KISS score. Before and after each dive FE NO values were measured using a hand-held electrochemical analyzer. Results There was no change in post-dive values of FE NO values (expressed in ppb = parts per billion) in the Air dive group (15.1 ± 3.6 ppb vs. 14.3 ± 4.7 ppb, n = 9, p = 0.32). There was a significant decrease in post-dive values of FE NO in the Oxygen dive group (15.6 ± 6 ppb vs. 11.7 ± 4.7 ppb, n = 9, p = 0.009). There was an even more pronounced decrease in the deep dive group (16.4 ± 6.6 ppb vs. 9.4 ± 3.5 ppb, n = 13, p < 0.001) and a significant correlation between KISS bubble score >0 (n = 13) and percentage decrease in post-dive FE NO values (r = -0.53, p = 0.03). Discussion Submersion and hyperbaric hyperoxia exposure cannot account entirely for these results suggesting the possibility that, in combination, one effect magnifies the other. A main finding of the present study is a significant relationship between reduction in exhaled NO concentration and dive-induced bubble formation. We postulate that exhaled NO concentration could be a useful index of decompression severity in healthy human divers. © 2014 Published by Elsevier Inc. 2014 Journal Article http://hdl.handle.net/20.500.11937/72002 10.1016/j.niox.2014.04.005 Elsevier Inc restricted |
| spellingShingle | Pontier, J. Buzzacott, Peter Nastorg, J. Dinh-Xuan, A. Lambrechts, K. Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title | Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title_full | Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title_fullStr | Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title_full_unstemmed | Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title_short | Exhaled nitric oxide concentration and decompression-induced bubble formation: An index of decompression severity in humans? |
| title_sort | exhaled nitric oxide concentration and decompression-induced bubble formation: an index of decompression severity in humans? |
| url | http://hdl.handle.net/20.500.11937/72002 |