Novel breathing pattern analysis: Symmetric Projection Attractor Reconstruction improves identification of impending COPD re-exacerbations – a retrospective cohort analysis

TY - JOUR

T1 - Novel breathing pattern analysis

T2 - Symmetric Projection Attractor Reconstruction improves identification of impending COPD re-exacerbations – a retrospective cohort analysis

AU - Serna Pascual, Miquel

AU - D'Cruz, Rebecca F.

AU - Volovaya, Maria

AU - Jolley, Caroline

AU - Hart, Nicholas

AU - Rafferty, Gerrard

AU - Steier, Joerg

AU - Aston, Philip

AU - Nandi, Manasi

PY - 2023/7/1

Y1 - 2023/7/1

N2 - Acute exacerbations of COPD (AECOPD) are the second most common cause of emergency hospitalisationworldwide, with one-quarter of patients readmitted within 30 days of discharge [1]. Each exacerbationaccelerates lung function decline [2] and is associated with a deterioration in health-related quality of life andan increased risk of mortality in the post-discharge period [3]. Several pathophysiological changes includingdecreased peak expiratory flow rate and increased dyspnoea often occur in the 3-5 days preceding anexacerbation [4]. This time window presents an opportunity to identify AECOPD, initiate patient selfmanagement and clinical interventions aimed at mitigating hospitalisation. Sensitive and specific biomarkers ofphysiological stress, which can be easily applied and interpreted in both community and clinical settings, wouldfacilitate earlier identification of AECOPD.Increased respiratory rate (RR) is a well-validated biomarker of respiratory stress that is often incorporated intopatient monitoring systems, facilitating early identification of deterioration [5]. Respiratorypressure/flow/plethysmography/thermistor waveforms are typically sampled as high-fidelity time-series data(~100-1000 Hz) and RR measurement automated to circumvent common inconsistencies with manual breathcounting, using algorithms to detect waveform peaks [6]. However, such analysis disregards the intermediatedata points which contain information about changes in waveform morphology, quantification of which couldalso help to identify physiological change. Symmetric Projection Attractor Reconstruction (SPAR) - a novelanalysis technique, overcomes this problem. SPAR replots every data point of any cyclic waveform, generatinga new visual representation (‘attractor’). Quantifiable attractor features can be extracted, providing newdiagnostic metrics pertaining to waveform morphology [7]. SPAR is resistant to baseline wander and haspreviously been successfully applied to cardiovascular waveforms [8]–[10].

AB - Acute exacerbations of COPD (AECOPD) are the second most common cause of emergency hospitalisationworldwide, with one-quarter of patients readmitted within 30 days of discharge [1]. Each exacerbationaccelerates lung function decline [2] and is associated with a deterioration in health-related quality of life andan increased risk of mortality in the post-discharge period [3]. Several pathophysiological changes includingdecreased peak expiratory flow rate and increased dyspnoea often occur in the 3-5 days preceding anexacerbation [4]. This time window presents an opportunity to identify AECOPD, initiate patient selfmanagement and clinical interventions aimed at mitigating hospitalisation. Sensitive and specific biomarkers ofphysiological stress, which can be easily applied and interpreted in both community and clinical settings, wouldfacilitate earlier identification of AECOPD.Increased respiratory rate (RR) is a well-validated biomarker of respiratory stress that is often incorporated intopatient monitoring systems, facilitating early identification of deterioration [5]. Respiratorypressure/flow/plethysmography/thermistor waveforms are typically sampled as high-fidelity time-series data(~100-1000 Hz) and RR measurement automated to circumvent common inconsistencies with manual breathcounting, using algorithms to detect waveform peaks [6]. However, such analysis disregards the intermediatedata points which contain information about changes in waveform morphology, quantification of which couldalso help to identify physiological change. Symmetric Projection Attractor Reconstruction (SPAR) - a novelanalysis technique, overcomes this problem. SPAR replots every data point of any cyclic waveform, generatinga new visual representation (‘attractor’). Quantifiable attractor features can be extracted, providing newdiagnostic metrics pertaining to waveform morphology [7]. SPAR is resistant to baseline wander and haspreviously been successfully applied to cardiovascular waveforms [8]–[10].

UR - http://www.scopus.com/inward/record.url?scp=85172232281&partnerID=8YFLogxK

U2 - 10.1183/23120541.00164-2023

DO - 10.1183/23120541.00164-2023

M3 - Letter

AN - SCOPUS:85172232281

SN - 2312-0541

VL - 9

JO - ERJ Open Research

JF - ERJ Open Research

IS - 4

M1 - 00164-2023

ER -