Effect of a novel viral filter on cardiopulmonary exercise testing during the COVID‐19 pandemic

Abstract

Cardiopulmonary exercise testing (CPET) before major surgery provides the best risk estimate of postoperative morbidity, mortality and consequent prognosis [1], yet is currently suspendedbecause of the hazards associatedwith aerosol-generating physical exercise and potential infective transmission [2]. While some services have transitioned to secondary, less informative assessments of cardiopulmonary function [3], novel counter-measures are required if surgical outcomes are to be optimised. Moreover, the related effect size is such that by July 2020, COVID-19 disease was associated with an 81-fold increase in the number of patients (n = 83,000) waiting > 1 year for NHS treatment in England alone [4]. Despite the transmission-reducing potential of porous microbacterial/ viral filters (BVF), concerns related to water vapour saturation and increased ventilatory resistance raise barriers to implementation [2]. The aim of our study was to investigate the effect of a novel BVF on cardiorespiratory parameters during CPET, in a randomised single-blind crossover study. Following ethical approval as a service evaluation (Cardiff and Vale University Health Board), 12 healthy, male participants with a mean (SD) age of 45 (10) years completed two separate CPET tests (seven days apart), with BVF and without (true value) BVF, distal to the sampling line. Participants performed a standardised incremental cycling