Exercise intolerance in post-coronavirus disease 2019 survivors after hospitalisation

Abstract

RationalePost-COVID19 survivors frequently have dyspnea that can lead to exercise intolerance and lower quality of life. Despite recent advances, the pathophysiological mechanisms of exercise intolerance in the post-COVID19 patients remain incompletely characterized.ObjectivesTo clarify the mechanisms of exercise intolerance in post-COVID19 survivors after hospitalization.MethodsProspective study evaluated consecutive patients previously hospitalized due to moderate-to-severe/critical COVID19. Within 90±10 days (mean±sd) of COVID19 acute symptoms onset, patients underwent a comprehensive cardiopulmonary assessment, including a cardiopulmonary exercise testing with earlobe arterialized capillary blood gas analysis.Measurements and Main ResultsEighty-seven patients were evaluated, their mean±sdpeak oxygen consumption were 19.5±5.0 ml kg−1·min−1, and the tertiles were: ≤17.0, 17.1–22.2 and ≥22.3 ml kg−1·min−1. Hospitalization severity was similar among the three groups; however, at the follow-up visit, they reported a greater sensation of dyspnea, along with indices of impaired pulmonary function, and abnormal ventilatory, gas-exchange and metabolic responses during exercise compared to patients with peak oxygen consumption >17 ml kg−1·min−1. By multivariate logistic regression analysis (ROC curve analysis) adjusted for age, sex and pulmonary embolism, a peak dead space fraction of tidal volume ≥29 and a resting forced vital capacity ≤80%predicted were independent predictors of reduced peak oxygen consumption.ConclusionsExercise intolerance in the post-COVID19 survivors was related to a high dead space fraction of tidal volume at peak exercise and a decreased resting forced vital capacity, suggesting that both pulmonary microcirculation injury and ventilatory impairment could influence aerobic capacity in this patient population.

Time to negative conversion and cardiopulmonary performance in athletes with COVID-19

“…In line this study, we also did not observe reduced exercise capacity. Airway obstruction, hyperventilation and reduced lung perfusion may be the main clinical conditions associated with high V′ E · V′ CO 2 −1 slope [ 13 – 15 ]. In addition, reduced exercise capacity and impaired ventilatory efficiency were present in smokers without airflow obstruction [ 16 ].…”