Respiratory Non-Invasive Venous Waveform Analysis for Assessment of Respiratory Distress in Coronavirus Disease 2019 Patients: An Observational Study.

Abstract

Due to the rapid rate of severe acute respiratory syndrome coronavirus 2 transmission and the heterogeneity of symptoms of coronavirus disease 2019, expeditious and effective triage is critical for early treatment and effective allocation of hospital resources. A post hoc analysis of respiratory data from non-invasive venous waveform analysis among patients enrolled in an observational study was performed. Vanderbilt University Medical Center. Peripheral venous waveforms were recorded from admission to discharge in enrolled coronavirus disease 2019-positive patients and healthy age-matched controls. Data were analyzed in LabChart 8 to transform venous waveforms to the frequency domain using fast Fourier transforms. The peak respiratory frequency was normalized to the peak cardiac frequency to generate a respiratory non-invasive venous waveform analysis respiratory index. Paired Fisher exact tests were used to compare each patient's respiratory non-invasive venous waveform analysis respiratory index at admission and discharge. A nonparametric one-way analysis of variance was used for multiple comparisons between patients with coronavirus disease 2019 and healthy controls for respiratory non-invasive venous waveform analysis respiratory index. Fifty coronavirus disease 2019-positive patients were enrolled between April 2020, and September 2020, and 45 were analyzed; 34 required supplemental oxygen and 11 did not. The respiratory non-invasive venous waveform analysis respiratory index was significantly higher for the 34 patients with coronavirus disease 2019 who received supplemental oxygen (median, 0.27; interquartile range, 0.11-1.28) compared with the 34 healthy controls (median, 0.06; interquartile range, 0.03-0.14) (p < 0.01). For patients with coronavirus disease 2019 who received supplemental oxygen, respiratory non-invasive venous waveform analysis respiratory index was significantly lower at hospital discharge (p = 0.02; 95% CI, 0.10-1.9) compared with hospital admission (median = 0.12; interquartile range, 0.05-0.56). For patients with coronavirus disease 2019, a respiratory non-invasive venous waveform analysis respiratory index of 0.64 demonstrated sensitivity of 92%, specificity of 47%, and positive predictive value of 93% for predicting requirement of supplemental oxygen during the hospitalization. Respiratory non-invasive venous waveform analysis respiratory index represents a novel physiologic respiratory measurement with a promising ability to triage early care and predict the need for oxygen support therapy in coronavirus disease 2019 patients.