Respiratory rehabilitation for Covid-19 related persistent dyspnoea: A one-year experience.

BACKGROUND: Growing consideration is emerging regarding the burden of persisting sequelae after SARS-CoV-2 infection. Out-patients exhibiting long Covid may benefit from ambulatory rehabilitation which is, to date, poorly documented. METHODS: A longitudinal follow-up over a one-year period was conducted in two ambulatory rehabilitation structures in order to describe the characteristics of real-life patients referred with Covid-19 sequelae and their evolution over the course of rehabilitation. RESULTS: 39 consecutive patients were included from April 1st, 2020 to April 1st, 2021. Patients were middle-aged (48 ± 15yr), without comorbidities, and mostly mild to moderate SARS-CoV-2 infection (25(64%) not requiring hospitalisation). Rehabilitation referral was considered with a median delay of 73[34-178] days after disease onset. Most prevalent symptoms were dyspnoea (n = 35(90%)) and fatigue (n = 30(77%)). Hyperventilation syndrome was highly frequent (n = 12(34%)). 29(74%) patients presented with prolonged functional sequelae, which was associated with younger age (43 ± 14 vs. 50 ± 10yr; p = 0.002), greater prevalence of hyperventilation syndrome (n = 12(41%) vs. 0(0%); p = 0.255) and poorer quality of life (VQ-11; 31 ± 10 vs. 23 ± 9; p = 0.030). Over the course of rehabilitation, exertional dyspnoea, 6-min walking distance, 3-min sit-to-stand test, hyperventilation syndrome prevalence and quality of life significantly improved. CONCLUSION: Hyperventilation is frequent in long Covid and may explain persistent dyspnoea as well as altered quality of life. Our data support screening of hyperventilation syndrome and functional impairment in mild Covid-19 out-patients as both of these components may improve with ambulatory rehabilitation.

Effects of hyperventilation with face mask on brain network in patients with epilepsy.

OBJECTIVES: During the ongoing pandemic of COVID-19, wearing face masks was recommended, including patients with epilepsy doing the hyperventilation (HV) test during electroencephalogram (EEG) examination somewhere. However, evidence was still limited about the effect of HV with face mask on cortical excitability of patients with epilepsy. The motivation of this work is to make use of the graph theory of EEG to characterize the cortical excitability of patients with epilepsy when they did HV under the condition wearing a surgical face mask. METHODS: We recruited 19 patients with epilepsy and 17 normal controls. All of participants completed two HV experiments, including HV with face mask (HV+) and HV without a mask (HV). The interval was 30 min and the sequence was random. Each experiment consisted of three segments: resting EEG, EEG of HV, and EEG of post-HV. EEG were recorded successively during each experiment. Participants were asked to evaluate the discomfort degree using a questionnaire when every HV is completed. RESULTS: All of the participants felt more uncomfortable after HV + . Moreover, not only HV decreased small-worldness index in patients with epilepsy, but also HV + significantly increased the clustering coefficient in patients with epilepsy. Importantly, the three-way of Mask*HV*Epilepsy showed interaction in the clustering coefficient in the delta band, as well as in the path length and the small-worldness index in the theta band. CONCLUSIONS: The results of this study indicated that patients with epilepsy showed the increased excitability of brain network during HV + . We should pay more attention to the adverse effect on brain network excitability caused by HV + in patients with epilepsy. In the clinical practice under the COVID-19 pandemic, it is important that the wearing face mask remain cautious for the individuals with epilepsy when they carried out HV behavior such as exercise (e.g., running, etc.).

Decreased CO2 Levels as Indicators of Possible Mechanical Ventilation-Induced Hyperventilation in COVID-19 Patients: A Retrospective Analysis.

Background: Six months since the outbreak of coronavirus disease (COVID-19), the pandemic continues to grow worldwide, although the outbreak in Wuhan, the worst-hit area, has been controlled. Thus, based on the clinical experience in Wuhan, we hypothesized that there is a relationship between the patient's CO2 levels and prognosis. Methods: COVID-19 patients' information was retrospectively collected from medical records at the Leishenshan Hospital, Wuhan. Logistic and Cox regression analyses were conducted to determine the correlation between decreased CO2 levels and disease severity or mortality risk. The Kaplan-Meier curve analysis was coupled with the log-rank test to understand COVID-19 progression in patients with decreased CO2 levels. Curve fitting was used to confirm the correlation between computed tomography scores and CO2 levels. Results: Cox regression analysis showed that the mortality risk of COVID-19 patients correlated with decreased CO2 levels. The adjusted hazard ratios for decreased CO2 levels in COVID-19 patients were 8.710 [95% confidence interval (CI): 2.773-27.365, P < 0.001], and 4.754 (95% CI: 1.380-16.370, P = 0.013). The adjusted odds ratio was 0.950 (95% CI: 0.431-2.094, P = 0.900). The Kaplan-Meier survival curves demonstrated that patients with decreased CO2 levels had a higher risk of mortality. Conclusions: Decreased CO2 levels increased the mortality risk of COVID-19 patients, which might be caused by hyperventilation during mechanical ventilation. This finding provides important insights for clinical treatment recommendations.