{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T16:17:18Z","timestamp":1770913038694,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T00:00:00Z","timestamp":1719446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We aim to provide reference values for military aircrews participating in hypoxia awareness training (HAT). We describe several parameters with potential biomedical interest based on selected segments and slopes of the changes in oxygen saturation (SatO2) during a standard HAT. A retrospective analysis of 2298 records of the SatO2 curve was performed, including 1526 military men aged 30.48 \u00b1 6.47 years during HAT in a hypobaric chamber. HAT consisted of pre-oxygenation at 100% and an ascent to 7620 m, followed by O2 disconnection starting the phase of descent of SatO2 until reaching the time of useful consciousness (TUC), and finally reconnection to 100% O2 in the recovery phase. Using an ad hoc computational procedure, the time taken to reach several defined critical values was computed. These key parameters were the time until desaturation of 97% and 90% (hypoxia) after oxygen mask disconnection (D97\/D90) and reconnection (R97\/R90) phases, the time of desaturation (TUC-D97) and hypoxia (TUC-D90) during disconnection, the total time in desaturation (L97) or hypoxia (L90), and the slopes of SatO2 drop (SDSAT97 and SDSAT90) and recovery (SRSAT97). The mean of the quartiles according to TUC were compared by ANOVA. The correlations between the different parameters were studied using Pearson\u2019s test and the effect size was estimated with \u03c92. Potentially useful parameters for the HAT study were those with statistical significance (p &lt; 0.05) and a large effect size. D97, D90, R97, and R90 showed significant differences with small effect sizes, while TUC-D97, TUC-D90, L97, L90, and SDSAT97 showed significant differences and large effect sizes. SDSAT97 correlated with TUC (R = 0.79), TUC-D97 (R = 0.81), and TUC-D90 (R = 0.81). In conclusion, several parameters of the SatO2 curve are useful for the study and monitoring of HAT. The SDSAT97 measured during the test can estimate the TUC and thus contribute to taking measures to characterize and protect the aircrew members.<\/jats:p>","DOI":"10.3390\/s24134168","type":"journal-article","created":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T04:19:26Z","timestamp":1719461966000},"page":"4168","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Oxygen Saturation Curve Analysis in 2298 Hypoxia Awareness Training Tests of Military Aircrew Members in a Hypobaric Chamber"],"prefix":"10.3390","volume":"24","author":[{"given":"Manuel","family":"Alvear-Catal\u00e1n","sequence":"first","affiliation":[{"name":"Centro de Medicina Aeroespacial (CMAE), Fuerza A\u00e9rea de Chile, Santiago 7550000, Chile"},{"name":"Secci\u00f3 de Fisiologia, Departament de Biologia Cel\u00b7lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudio","family":"Montiglio","sequence":"additional","affiliation":[{"name":"Centro de Medicina Aeroespacial (CMAE), Fuerza A\u00e9rea de Chile, Santiago 7550000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Danilo","family":"Aravena-Nazif","sequence":"additional","affiliation":[{"name":"Centro de Medicina Aeroespacial (CMAE), Fuerza A\u00e9rea de Chile, Santiago 7550000, Chile"},{"name":"Facultad de Medicina, Cl\u00ednica Alemana Universidad del Desarrollo, Santiago 7610315, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4942-2346","authenticated-orcid":false,"given":"Gin\u00e9s","family":"Viscor","sequence":"additional","affiliation":[{"name":"Secci\u00f3 de Fisiologia, Departament de Biologia Cel\u00b7lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9501-3159","authenticated-orcid":false,"given":"Oscar F.","family":"Araneda","sequence":"additional","affiliation":[{"name":"Integrative Laboratory of Biomechanics and Physiology of Effort, (LIBFE), School of Kinesiology, Faculty of Medicine, Universidad de los Andes, Santiago 7620001, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1016\/S0140-6736(02)78146-4","article-title":"Notes of Effects Experienced during Recent Balloon Ascents","volume":"80","author":"Glaisher","year":"1862","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1089\/ham.2004.5.453","article-title":"Paralysis and Blindness during a Balloon Ascent to High Altitude","volume":"5","author":"West","year":"2004","journal-title":"High Alt. 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