Cited by 71Non-Invasive Vital Sign MonitoringECG Monitoring and AnalysisHeart Rate Variability and Autonomic Control

A Robust Fusion Model for Estimating Respiratory Rate From Photoplethysmography and Electrocardiography

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Birrenkott, Drew A., Pimentel, Marco A.F., Watkinson, Peter J., Clifton, David A.·2018·IEEE Transactions on Biomedical Engineering

Abstract

OBJECTIVE: Respiratory rate (RR) estimation algorithms based on the photoplethymogram (PPG) and electrocardiogram (ECG) lack clinical robustness. This is because the PPG and ECG respiratory modulations are dependent on patient physiology, regardless of general signal quality. The present work describes an RR estimation algorithm using respiratory quality indices (RQIs) that assess the presence or absence of the PPG- and ECG-derived respiratory modulations. METHODS: Six respiratory waveforms are derived from the amplitude modulation, frequency modulation, and baseline wander of the PPG and ECG. The respiratory quality of each modulation is assessed by using RQIs based on the fast Fourier transform, autoregression, and autocorrelation. The individual RQIs are fused to obtain a single RQI per modulation per time window. Based on a tunable threshold, the RQIs are used to discard poor modulations and weight the remaining modulations to provide a single RR estimation per time window. RESULTS: The proposed method was tested on two independent datasets and found that using a conservative threshold, the mean absolute error was 0.71 $\pm$ 0.89 and 3.12 $\pm$ 4.39 brpm while discarding only 1.3% and 23.2% of all time windows, for each dataset, respectively. CONCLUSION: These errors are either better than or comparable to current methods, and the number of windows discarded is far lower demonstrating improved robustness. SIGNIFICANCE: This work describes a novel preprocessing algorithm that can be implemented in conjunction with other RR estimation techniques to improve robustness by specifically considering the quality of the respiratory information.

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Crossref · 10.1109/tbme.2017.2778265

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  • A key challenge for RR algorithms is to make them robust to signal artifact and only output values associated with a high degree of confidence, particularly when used with wearable data.

    “A key challenge is to make algorithms robust to signal artifact and only output values associated with a high degree of confidence”

    From Wearable Photoplethysmography for Cardiovascular Monitoring (2022) · cites this paper as [89]

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Research works printed but not linked: 3

  1. P. Charlton et al., "Respiratory rate estimation from the electrocardiogram and photoplethysmogram: A review," IEEE Rev. Biomed. Eng. [Online]. Available: http://ieeexplore.ieee.org/document/8081839/
  2. D. Birrenkott, "Respiratory quality indices for ECG-and PPG-derived respiratory data," D.Phil transfer of status report, Dept. of Eng. Science, University of Oxford, Oxford, U.K., 2015.
  3. D. Meredith et al., "Monitoring of vital signs during haemodialysis," in Proc. Brit. Renal Assoc. Conf., 2010, p. 355.

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Authors
Birrenkott, D. A., Pimentel, M. A. F., Watkinson, P. J., & Clifton, D. A.
Affiliations
  • University of Oxford (GB)
  • Oxford University Hospitals NHS Trust (GB)
Venue
IEEE Transactions on Biomedical Engineering
Published
2018-09
Volume
65
Issue
9
Pages
2033-2041
ISSN
  • 0018-9294 (ISSN-L)
  • 1558-2531
OpenAlex
W2776923905
Cited by
71
References
29
Citations by year
2026: 6 · 2025: 6 · 2024: 7 · 2023: 8 · 2022: 11 · 2021: 9 · 2020: 13 · 2019: 8 · 2018: 2 · 2017: 1
FWCI
2.95
Type
journal article
Language
en
Open access
Locations
  • IEEE Transactions on Biomedical Engineering (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • Wellcome Trust (WT 088877/Z/09/Z)
  • The Rhodes Trust
Topics
  • Physical Sciences › Engineering › Biomedical Engineering › Non-Invasive Vital Sign Monitoring
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › ECG Monitoring and Analysis
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Heart Rate Variability and Autonomic Control
Keywords
respiratory rate estimation, photoplethysmography, electrocardiogram, multimodal signal fusion, amplitude modulation, frequency modulation, baseline wander, signal quality assessment, autoregression, autocorrelation, fast Fourier transform, robustness
MeSH terms
Algorithms, Electrocardiography, Humans, Signal Processing, Computer-Assisted, Photoplethysmography, Respiratory Rate

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