A quantitative approach to assess similarity between dives under the Bühlmann decompression algorithm constraints
Year: 2026
Type: preprint
Abstract: Undersea and high-altitude operations regularly put operators at risk for decompression sickness (DCS), which is attributed to bubble formation and growth during decompression. DCS mitigation strategies are validated with empirical testing, often conducted in hyperbaric chambers, which provide precise control of the pressure-time profile. A degree of variability for study outcome is anticipated in both decompression sickness (DCS) and venous gas emboli (VGE) endpoints. Experimentation in a chamber offers precision, but is not always practical or operationally relevant, leading researchers to use open water for the dive exposure. Dive profile consistency may vary by diver skill level and environmental conditions, potentially introducing dive profile deviations, which may be a factor of individual variability. There does not exist a quantitative framework for evaluating dive profile consistency and quantifying deviations in open water studies. In this work, we evaluate existing dive profile metrics and propose a workflow to estimate dive profile deviations using the Bühlmann dissolved gas phase model. The dive profile metrics included depth and time-based calculations, as well as surface gradient factor, degree-of-conservatism and the root mean square error of the Bühlmann tissue compartments. We developed a set of simulated dive profiles and obtained a set of 40 open water dives previously collected by certified divers, both of which were used to evaluate performance of the dive profile metrics. Depth and time-based metrics offered sensitivity to varying depths and time durations of the dive profiles, respectively. For the field dives, we found the Bühlmann root mean square error metric performed best at identifying the deviation profile, followed by pressure root time. These evaluations demonstrate the utility and limitations of previously published dive profile metrics and emphasize the importance of accounting for dive profile consistency in open water decompression trials. New & Noteworthy Inter-individual variability in response to decompression stress has been documented for participants completing the same dive exposure, in either a hyperbaric chamber or in open water. Dives in open water are not afforded the same pressure-time control as those in a hyperbaric chamber. We developed a pipeline using an established dissolved gas phase model to quantify depth-time profile deviation for open water human diver studies. We evaluated our workflow against pre-existing metrics and found inconsistencies. Dive profile variability should be considered in open-water decompression studies.
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7214016899