{"id":3544,"date":"2011-07-08T14:33:02","date_gmt":"2011-07-08T14:33:02","guid":{"rendered":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/?p=3544"},"modified":"2011-10-14T15:47:25","modified_gmt":"2011-10-14T15:47:25","slug":"a-wearable-vital-signs-monitor-at-the-ear-2","status":"publish","type":"post","link":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/a-wearable-vital-signs-monitor-at-the-ear-2\/","title":{"rendered":"A Wearable Vital Signs Monitor at the Ear"},"content":{"rendered":"<div class=\"pf-content\"><p>Vital signs such as heart rate, blood pressure, blood oxygenation, cardiac output, and respiratory rate are necessary in determining the overall health of a patient.\u00a0 Continuous monitoring of these vital signs can help assess the wearer&#8217;s overall state of health and identify risks for cardiovascular diseases<sup> [<a href=\"#footnote_0_3544\" id=\"identifier_0_3544\" class=\"footnote-link footnote-identifier-link\" title=\"S. D. Pierdomenico, M. Di Nicola, A. L. Esposito, R. Di Mascio, E. Ballone, D. Lapenna, F. Cuccurullo, &ldquo;Prognostic value of different indices of blood pressure variability in hypertensive patients,&rdquo; American Journal of Hypertension, vol. 22(8), pp. 842-847, June 2009.\">1<\/a>] <\/sup>.<\/p>\n<p>We propose the site behind the ear as a location for an integrated wearable vital signs monitor<sup> [<a href=\"#footnote_1_3544\" id=\"identifier_1_3544\" class=\"footnote-link footnote-identifier-link\" title=\"D. He, E. S. Winokur, T. Heldt, C. G. Sodini, &ldquo;The ear as a location for wearable vital signs monitoring,&rdquo; Proc. of the IEEE Engineering in Medicine and Biology Conference, Sept. 2010, pp. 6389-6392.\">2<\/a>] <\/sup>. This location offers physiological signals such as the electrocardiogram (ECG), the photoplethysmogram (PPG), and the head ballistocardiogram (hBCG). The ECG measures the electrical activity from the heart and offers information such as continuous heart rate, blood pressure (when coupled with PPG or hBCG), and respiratory rate. The PPG measures the blood volume and color under the skin using optical illumination. The PPG offers information such as continuous heart rate and blood oxygenation. The hBCG measures the head&#8217;s mechanical reaction to the blood expelled by the heart and offers information about continuous heart rate, cardiac output, and respiratory rate.<\/p>\n<p>A simultaneous measurement of ECG, PPG, and hBCG is shown in Figure 1. Using the peak timing data from ECG, PPG, and hBCG, blood pressure can be estimated. Figure 2 compares the estimated blood pressure with a commercial blood pressure measurement during a Valsalva breath-hold maneuver.<\/p>\n<p>To make the monitor wearable, the electrodes must be small, comfortable, and gel-less to avoid skin irritation. We use 1-cm<sup>2<\/sup> capacitive and dry electrodes made of wearable fabric materials. The device is designed to use the ear as a discreet and a natural anchor that reduces device visibility and the need for skin adhesives.<\/p>\n\n\t\t<style type=\"text\/css\">\n\t\t\t#gallery-1 {\n\t\t\t\tmargin: auto;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-item {\n\t\t\t\tfloat: left;\n\t\t\t\tmargin-top: 10px;\n\t\t\t\ttext-align: center;\n\t\t\t\twidth: 50%;\n\t\t\t}\n\t\t\t#gallery-1 img {\n\t\t\t\tborder: 2px solid #cfcfcf;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-caption {\n\t\t\t\tmargin-left: 0;\n\t\t\t}\n\t\t\t\/* see gallery_shortcode() in wp-includes\/media.php *\/\n\t\t<\/style>\n\t\t<div id='gallery-1' class='gallery galleryid-3544 gallery-columns-2 gallery-size-medium'><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_01.jpg' rel=\"lightbox[3544]\"><img width=\"300\" height=\"224\" src=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_01-300x224.jpg\" class=\"attachment-medium size-medium\" alt=\"Figure 1\" loading=\"lazy\" aria-describedby=\"gallery-1-3545\" srcset=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_01-300x224.jpg 300w, https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_01-1024x766.jpg 1024w, https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_01.jpg 1182w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-3545'>\n\t\t\t\tFigure 1: Simultaneous measurements of chest ECG, ear PPG, and ear hBCG.\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_02.jpg' rel=\"lightbox[3544]\"><img width=\"300\" height=\"267\" src=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_02-300x267.jpg\" class=\"attachment-medium size-medium\" alt=\"Figure 2\" loading=\"lazy\" aria-describedby=\"gallery-1-3546\" srcset=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_02-300x267.jpg 300w, https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/07\/he_vital_02.jpg 940w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-3546'>\n\t\t\t\tFigure 2: Top \u2013 Estimated relative blood pressure using ECG and hBCG timing data during a Valsalva maneuver. Bottom \u2013 Commercial blood pressure measurement during a Valsalva maneuver.\n\t\t\t\t<\/dd><\/dl><br style=\"clear: both\" \/>\n\t\t<\/div>\n\n<\/div><ol class=\"footnotes\"><li id=\"footnote_0_3544\" class=\"footnote\">S. D. Pierdomenico, M. Di Nicola, A. L. Esposito, R. Di Mascio, E. Ballone, D. <a href=\"http:\/\/www.ncbi.nlm.nih.gov\/pubmed?term=%22Lapenna%20D%22%5BAuthor%5D\">Lapenna<\/a>, F. Cuccurullo, &#8220;Prognostic value of different indices of blood pressure variability in hypertensive patients,&#8221; <em>American Journal of Hypertension<\/em>, vol. 22(8), pp. 842-847, June 2009. [<a href=\"#identifier_0_3544\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><li id=\"footnote_1_3544\" class=\"footnote\">D. He, E. S. Winokur, T. Heldt, C. G. Sodini, \u201cThe ear as a location for wearable vital signs monitoring,\u201d <em>Proc. of the IEEE Engineering in Medicine and Biology Conference<\/em>, Sept. 2010, pp. 6389-6392. [<a href=\"#identifier_1_3544\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><\/ol>","protected":false},"excerpt":{"rendered":"<p>Vital signs such as heart rate, blood pressure, blood oxygenation, cardiac output, and respiratory rate are necessary in determining the&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[26,5530],"tags":[6222,75,4147,4148],"_links":{"self":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/3544"}],"collection":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/comments?post=3544"}],"version-history":[{"count":4,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/3544\/revisions"}],"predecessor-version":[{"id":4354,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/3544\/revisions\/4354"}],"wp:attachment":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/media?parent=3544"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/categories?post=3544"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/tags?post=3544"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}