open access
Theoretical tissue compartment inert gas pressures during a deep dive with and without deep decompression stops: a case analysis
open access
Abstract
Background: Deep decompression stops are increasingly common in recreational technical diving. Concerns exist that they shift decompression stress back into slower tissues. A diver recorded an exceptional exposure dive, with deeps stops, on a commercially available dive computer.
Material and methods: Using the R package SCUBA tissue inert gas pressures in 17 Bühlmann (ZH-L16A) compartments were estimated from the dive computer recorded profile. The RGBM dive plan generated by the diver’s software was similarly interrogated, as was a third profile with reduced deep stops generated using the VPM-B/E model.
Results: In this dive the combination of 5 gas switches appeared to ameliorate the effect of deep stops from 76 m depth.
Conclusions: A higher-than-anticipated inert gas content in a decompression mixture, coupled with climbing 200 stairs post-decompression, appear possible risk factors for decompression sickness. Nonetheless, the physiological effect of deep decompression stops during exceptional exposure, even when diving with gas switches, remains urgently to be determined to improve safe decompression following exceptional exposures. Until algorithms utilising deep decompression stops are validated with human data, dive profiles incorporating deep decompression stops should be considered experimental.
Abstract
Background: Deep decompression stops are increasingly common in recreational technical diving. Concerns exist that they shift decompression stress back into slower tissues. A diver recorded an exceptional exposure dive, with deeps stops, on a commercially available dive computer.
Material and methods: Using the R package SCUBA tissue inert gas pressures in 17 Bühlmann (ZH-L16A) compartments were estimated from the dive computer recorded profile. The RGBM dive plan generated by the diver’s software was similarly interrogated, as was a third profile with reduced deep stops generated using the VPM-B/E model.
Results: In this dive the combination of 5 gas switches appeared to ameliorate the effect of deep stops from 76 m depth.
Conclusions: A higher-than-anticipated inert gas content in a decompression mixture, coupled with climbing 200 stairs post-decompression, appear possible risk factors for decompression sickness. Nonetheless, the physiological effect of deep decompression stops during exceptional exposure, even when diving with gas switches, remains urgently to be determined to improve safe decompression following exceptional exposures. Until algorithms utilising deep decompression stops are validated with human data, dive profiles incorporating deep decompression stops should be considered experimental.
Keywords
diving computer, decompression, deep diving, gas solubility, models, technical diving
Title
Theoretical tissue compartment inert gas pressures during a deep dive with and without deep decompression stops: a case analysis
Journal
Issue
Article type
Original article
Pages
36-42
Published online
2015-03-19
Page views
2804
Article views/downloads
2841
DOI
10.5603/IMH.2015.0010
Pubmed
Bibliographic record
IMH 2015;66(1):36-42.
Keywords
diving computer
decompression
deep diving
gas solubility
models
technical diving
Authors
Peter Buzzacott
Virginie Papadopoulou
Adrian Baddeley
Nadan M. Petri
Folke Lind