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Schirato et al. | Journal of Clinical and Translational Research 2024; 10(5): 269-282 279
Finally, if the decompression proceeds at a pace that allows Conflicts of Interest
neutrophils to become active but not activated by platelet- and
endothelial-derived MPs, they will inhibit the ongoing The authors have no competing interests.
inflammatory process initiated earlier. Bubble formation would Ethics Approval and Consent to Participate
likely be minimal due to the absence of nucleation sources,
resulting in the individual surfacing with low physiological stress. The volunteers provided written informed consent. The
The levels of supersaturation required to trigger the processes ethical committee of the Biosciences Institute of the University
depend on individual responses, i.e., activation of the person’s of Sao Paulo approved the experimental protocol (CAE
inflammatory processes. Moreover, the correlation between #91231618.6.0000.5464), and all experiments were performed
HRV and the degree of stress (sympathetic tonus) seems to be in accordance with relevant guidelines and regulations.
highly individualized. Notably, different decompression profiles
generate different tissue supersaturation upon surfacing. The Consent for Publication
composition of the breathing gases (i.e., the fraction of oxygen All volunteers signed an informed consent before joining the
and the presence of helium) causes different physiological experiments.
responses. It might be possible to speculate the existence of a
dose-dependent response, where lower tissue supersaturation Availability of Data
would lead to little or no physiological alterations, while higher Data are available from the corresponding author upon
tissue supersaturations would lead to progressively greater reasonable request.
physiological responses and subsequently the development of
decompression sickness. References
Our proposed schematics presented in Figure 11 highlight
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given decompression profile. [3] Howle LE, Weber PW, Hada EA, Vann RD, Denoble PJ.
Of course, the ideas presented in this study should be The Probability and Severity of Decompression Sickness.
interpreted with caution due to the small cohort of investigated PLoS One 2017;12(3):1-25.
divers and the large inter-individual variance observed in the
variables analyzed. Besides, it is important to note that the doi: 10.1371/journal.pone.0172665
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the data obtained in chamber and swimming pool dives, already Decompression Dives. Panama City: Navy Experimental
presented in other studies, displayed similar patterns. Diving Unit; 2011.
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profiles trigger different physiological responses. Whether these Decompression from 82 fsw (25 m) Significantly Reduces
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however, that, according to the scheme described in Figure 11 Dimensional Echocardiography are an Imperfect
and further developed by Schirato et al. [65], they might play a Surrogate Endpoint for Decompression Sickness. Diving
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Acknowledgments [8] Doolette DJ, Murphy FG, Gerth WA. Thalmann
Algorithm parameter sets for support of constant 1.3
None. atm PO He-O diving to 300 fsw. Panama City:Navy
2
2
Experimental Diving Unit; 2018.
Funding
[9] Madden LA, Laden G. Gas Bubbles may not be the
None. Underlying cause of Decompression Illness - the at-
DOI: https://doi.org/10.36922/jctr.24.00021