{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,25]],"date-time":"2026-04-25T01:02:23Z","timestamp":1777078943683,"version":"3.51.4"},"reference-count":127,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,10]],"date-time":"2020-11-10T00:00:00Z","timestamp":1604966400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"U.S. Army Medical Research and Development Command and the Congressionally Directed Medical Research Program","award":["DM180240"],"award-info":[{"award-number":["DM180240"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Vital signs historically served as the primary method to triage patients and resources for trauma and emergency care, but have failed to provide clinically-meaningful predictive information about patient clinical status. In this review, a framework is presented that focuses on potential wearable sensor technologies that can harness necessary electronic physiological signal integration with a current state-of-the-art predictive machine-learning algorithm that provides early clinical assessment of hypovolemia status to impact patient outcome. The ability to study the physiology of hemorrhage using a human model of progressive central hypovolemia led to the development of a novel machine-learning algorithm known as the compensatory reserve measurement (CRM). Greater sensitivity, specificity, and diagnostic accuracy to detect hemorrhage and onset of decompensated shock has been demonstrated by the CRM when compared to all standard vital signs and hemodynamic variables. The development of CRM revealed that continuous measurements of changes in arterial waveform features represented the most integrated signal of physiological compensation for conditions of reduced systemic oxygen delivery. In this review, detailed analysis of sensor technologies that include photoplethysmography, tonometry, ultrasound-based blood pressure, and cardiogenic vibration are identified as potential candidates for harnessing arterial waveform analog features required for real-time calculation of CRM. The integration of wearable sensors with the CRM algorithm provides a potentially powerful medical monitoring advancement to save civilian and military lives in emergency medical settings.<\/jats:p>","DOI":"10.3390\/s20226413","type":"journal-article","created":{"date-parts":[[2020,11,10]],"date-time":"2020-11-10T14:10:41Z","timestamp":1605017441000},"page":"6413","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Wearable Sensors Incorporating Compensatory Reserve Measurement for Advancing Physiological Monitoring in Critically Injured Trauma Patients"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9246-0554","authenticated-orcid":false,"given":"Victor A.","family":"Convertino","sequence":"first","affiliation":[{"name":"Battlefield Health &amp; Trauma Center for Human Integrative Physiology, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"},{"name":"Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA"}]},{"given":"Steven G.","family":"Schauer","sequence":"additional","affiliation":[{"name":"Battlefield Health &amp; Trauma Center for Human Integrative Physiology, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"},{"name":"Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA"},{"name":"Brooke Army Medical Center, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9155-3556","authenticated-orcid":false,"given":"Erik K.","family":"Weitzel","sequence":"additional","affiliation":[{"name":"Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA"},{"name":"Brooke Army Medical Center, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"},{"name":"59th Medical Wing, JBSA Lackland, San Antonio, TX 78236, USA"}]},{"given":"Sylvain","family":"Cardin","sequence":"additional","affiliation":[{"name":"Navy Medical Research Unit, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"}]},{"given":"Mark E.","family":"Stackle","sequence":"additional","affiliation":[{"name":"Commander, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"}]},{"given":"Michael J.","family":"Talley","sequence":"additional","affiliation":[{"name":"Commanding General, US Army Medical Research and Development Command, Fort Detrick, Frederick, MD 21702, USA"}]},{"given":"Michael N.","family":"Sawka","sequence":"additional","affiliation":[{"name":"Georgia Institute of Technology, Atlanta, GA 30332, USA"}]},{"given":"Omer T.","family":"Inan","sequence":"additional","affiliation":[{"name":"Georgia Institute of Technology, Atlanta, GA 30332, USA"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"292","DOI":"10.1097\/CNQ.0b013e318255d6b3","article-title":"The importance of vital signs in the triage of injured patients","volume":"35","author":"Charlari","year":"2013","journal-title":"Crit. 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