{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T13:39:22Z","timestamp":1784295562768,"version":"3.55.0"},"reference-count":37,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T00:00:00Z","timestamp":1776211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      The leading cause of preventable traumatic death is hemorrhage. Early detection of hemorrhagic shock remains a critical challenge. For the early prediction of hemorrhagic shock-related cardiovascular decompensation, our team has developed the compensatory reserve measurement (CRM) algorithm. CRM uses a photoplethysmography waveform to quantify the body\u2019s capacity to compensate during hypovolemia. This study focuses on the development and use of an application that can predict CRM in real-time (CRM\n                      <jats:sub>RT<\/jats:sub>\n                      ) during simulated hypovolemia experiments.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      The CRM\n                      <jats:sub>RT<\/jats:sub>\n                      application was developed in Python to generate CRM predictions and highlight trend trajectories in real-time (RT). Data were collected during a human research protocol that was reviewed and approved by the Institutional Review Board. Participants (n = 20) meeting the inclusion criteria underwent a simulated hypovolemia procedure in a lower-body negative pressure chamber while wearing a Masimo\u00ae MightySat\u00ae Rx pulse oximeter. Data were streamed in RT via a Bluetooth\u00ae connection to a computer running the CRM\n                      <jats:sub>RT<\/jats:sub>\n                      application.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      CRM was successfully implemented for RT data capture during the research study. The CRM\n                      <jats:sub>RT<\/jats:sub>\n                      application achieved a median performance error of \u22120.95%, while the median absolute performance error was higher at 19.00%. CRM\n                      <jats:sub>RT<\/jats:sub>\n                      resulted in an average early prediction time of 18.3\u00a0min by tracking the slope trend changes in RT.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>\n                      The CRM\n                      <jats:sub>RT<\/jats:sub>\n                      application effectively tracked CRM during simulated hypovolemia using a wearable non-invasive sensor. Predictions served as an earlier indicator of hemorrhage compared to traditional vital signs, addressing a limitation of current triage practices. Overall, the CRM\n                      <jats:sub>RT<\/jats:sub>\n                      application represents a promising advancement toward RT prediction of hypovolemic decompensation.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fbioe.2026.1756626","type":"journal-article","created":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T05:45:57Z","timestamp":1776231957000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Experimental evaluation of a real-time implementation of compensatory reserve measurement in a human model of hemorrhagic shock"],"prefix":"10.3389","volume":"14","author":[{"given":"Ryan","family":"Ortiz","sequence":"first","affiliation":[{"name":"Organ Support & Automation Technologies Department, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jose M.","family":"Gonzalez","sequence":"additional","affiliation":[{"name":"Organ Support & Automation Technologies Department, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tina","family":"Rodgers","sequence":"additional","affiliation":[{"name":"Organ Support & Automation Technologies Department, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofia I.","family":"Hernandez Torres","sequence":"additional","affiliation":[{"name":"Organ Support & Automation Technologies Department, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victor A.","family":"Convertino","sequence":"additional","affiliation":[{"name":"Battlefield Health & Trauma Center for Human Integrative Physiology, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]},{"name":"Department of Medicine, Uniformed Services University of the Health Sciences","place":["Bethesda, MD, United States"]},{"name":"Department of Emergency Medicine, University of Texas Health Science Center","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric J.","family":"Snider","sequence":"additional","affiliation":[{"name":"Organ Support & Automation Technologies Department, U.S. Army Institute of Surgical Research","place":["San Antonio, TX, United States"]},{"name":"Department of Surgery, University of Texas Health Science Center","place":["San Antonio, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,15]]},"reference":[{"key":"B1","first-page":"60","article-title":"Review of trauma care in the prehospital setting: hemorrhage control and assessment tools","volume":"21","author":"Albeshri","year":"2025","journal-title":"Rev. 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