Comparison of different modulations of photoplethysmography in extracting respiratory rate: from a physiological perspective

Liu, Haipeng1; Chen, Fei2; Hartmann, Vera3; Khalid, Syed Ghufran1; Hughes, Stephen3; Zheng, Dingchang1

2020-09

10.1088/1361-6579/abaaf0

PHYSIOLOGICAL MEASUREMENT   影响因子和分区

0967-3334

1361-6579

Objective: Based on different physiological mechanisms, the respiratory modulations of photoplethysmography (PPG) signals differ in strength and resultant accuracy of respiratory frequency (RF) estimations. We aimed to investigate the strength of different respiratory modulations and the accuracy of resultant RF estimations in different body sites and two breathing patterns.Approach: PPG and reference respiratory signals were simultaneously measured over 60 s from 36 healthy subjects in six sites (arm, earlobe, finger, forehead, wrist-under (volar side), wrist-upper (dorsal side)). Respiratory signals were extracted from PPG recordings using four demodulation approaches: amplitude modulation (AM), baseline wandering (BW), frequency modulation (FM) and filtering. RFs were calculated from the PPG-derived and reference respiratory signals. To investigate the strength of respiratory modulations, the energy proportion in the range that covers 75% of the total energy in the reference respiratory signal, with RF in the middle, was calculated and compared between different modulations. Analysis of variance and the Scheirer-Ray-Hare test were performed withpost hocanalysis.Mainresults: In normal breathing, FM was the only modulation whose RF was not significantly different from the reference RF (p > 0.05). Compared with other modulations, FM was significantly higher in energy proportion (p < 0.05) and lower in RF estimation error (p < 0.05). As to energy proportion, measurements from the finger and the forehead were not significantly different (p > 0.05), but both were significantly different from the other four sites (p < 0.05). In deep breathing, the RFs derived by BW, filtering and FM were not significantly different from the reference RF (p > 0.05). The RF estimation error of FM was significantly less than that of AM or BW (p < 0.05). The energy proportion of FM was significantly higher than that of other modulations (p < 0.05).Significance: Of all the respiratory modulations, FM has the highest strength and is appropriate for accurate RF estimation from PPG signals recorded at different sites and for different breathing patterns.

photoplethysmography (PPG) respiratory frequency respiratory modulation

SCI ; EI

英语

通讯

National Natural Science Foundation of China[61828104] ; Basic Research Foundation of Shenzhen[JCYJ20160509162237418] ; Newton Funds Industry Academia Partnership Programme[IAPP1R2/100204]

Biophysics ; Engineering ; Physiology

Biophysics ; Engineering, Biomedical ; Physiology

WOS:000575786900001

IOP PUBLISHING LTD

20215211390830

Amplitude modulation ; Frequency estimation ; Frequency modulation ; Physiology

Medicine and Pharmacology:461.6 ; Biology:461.9

BIOLOGY & BIOCHEMISTRY

Web of Science

1.Coventry Univ, Fac Hlth & Life Sci, Res Ctr Intelligent Healthcare, Coventry CV1 5FB, W Midlands, England
2.Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen 518055, Peoples R China
3.Anglia Ruskin Univ, Fac Hlth Educ Med & Social Care, Sch Allied Hlth, Chelmsford CM1 1SQ, Essex, England

Liu, Haipeng,Chen, Fei,Hartmann, Vera,et al. Comparison of different modulations of photoplethysmography in extracting respiratory rate: from a physiological perspective[J]. PHYSIOLOGICAL MEASUREMENT,2020,41(9).

Liu, Haipeng,Chen, Fei,Hartmann, Vera,Khalid, Syed Ghufran,Hughes, Stephen,&Zheng, Dingchang.(2020).Comparison of different modulations of photoplethysmography in extracting respiratory rate: from a physiological perspective.PHYSIOLOGICAL MEASUREMENT,41(9).

Liu, Haipeng,et al."Comparison of different modulations of photoplethysmography in extracting respiratory rate: from a physiological perspective".PHYSIOLOGICAL MEASUREMENT 41.9(2020).