Abstract:
:Remote sensing of the reflectance photoplethysmogram using a video camera typically positioned 1 m away from the patient's face is a promising method for monitoring the vital signs of patients without attaching any electrodes or sensors to them. Most of the papers in the literature on non-contact vital sign monitoring report results on human volunteers in controlled environments. We have been able to obtain estimates of heart rate and respiratory rate and preliminary results on changes in oxygen saturation from double-monitored patients undergoing haemodialysis in the Oxford Kidney Unit. To achieve this, we have devised a novel method of cancelling out aliased frequency components caused by artificial light flicker, using auto-regressive (AR) modelling and pole cancellation. Secondly, we have been able to construct accurate maps of the spatial distribution of heart rate and respiratory rate information from the coefficients of the AR model. In stable sections with minimal patient motion, the mean absolute error between the camera-derived estimate of heart rate and the reference value from a pulse oximeter is similar to the mean absolute error between two pulse oximeter measurements at different sites (finger and earlobe). The activities of daily living affect the respiratory rate, but the camera-derived estimates of this parameter are at least as accurate as those derived from a thoracic expansion sensor (chest belt). During a period of obstructive sleep apnoea, we tracked changes in oxygen saturation using the ratio of normalized reflectance changes in two colour channels (red and blue), but this required calibration against the reference data from a pulse oximeter.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Tarassenko L,Villarroel M,Guazzi A,Jorge J,Clifton DA,Pugh Cdoi
10.1088/0967-3334/35/5/807subject
Has Abstractpub_date
2014-05-01 00:00:00pages
807-31issue
5eissn
0967-3334issn
1361-6579journal_volume
35pub_type
杂志文章abstract::In this study, a framework for the characterization of the dynamic interactions between RR variability (RRV) and systolic arterial pressure variability (SAPV) is proposed. The methodology accounts for the intrinsic non-stationarity of the cardiovascular system and includes the assessment of both the strength and the p...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/3/315
更新日期:2012-03-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/1361-6579/aab659
更新日期:2018-04-26 00:00:00
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更新日期:2019-04-03 00:00:00
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pub_type: 杂志文章
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更新日期:1994-05-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2017-05-01 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aaaaa0
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pub_type: 杂志文章,评审
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更新日期:2011-07-01 00:00:00
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doi:10.1088/1361-6579/38/2/310
更新日期:2017-02-01 00:00:00
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更新日期:2017-03-01 00:00:00
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更新日期:2017-11-30 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2018-06-19 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/25/6/n01
更新日期:2004-12-01 00:00:00
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更新日期:2003-05-01 00:00:00
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更新日期:2019-12-02 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/10/006
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2016-02-01 00:00:00
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