Decrease of exercise endurance in critically ill COVID-19 survivors: 4 case reports (preprint)

Background: The Coronavirus Disease 2019 (COVID-19) already have been as a pandemic. However, knowledge about the sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains limited. Here we descirbe the pulmonary function test (PFT) and cardiopulmonary exercise test (CPET) of critically ill COVID-19 in four cases with sereve acute respiratory distress syndrome (ARDS) after discharge.Case presentation: We introduce four patients who complained of fever, cough, chest tightness and other symptoms, all of them were confirmed as SARS-CoV-2 infection by real-time reverse transcription polymerase chain reaction (RT-PCR). They were treated with mechanical ventilation because of severe ARDS. After respiratory support, antiviral and anti-infective treatment, they were weaned from mechanic ventilation with the improvement of hypoxemia. All patients were discharged from the hospital after completion of treatment and had no mortality. Around 1-month post-discharge, they were followed up for chest computed tomography (CT) scan, and performed PFT and CPET. Peak oxygen uptake of predicted (peakVO2% pred) decreased in all four cases, although spirometry were in the normal range, and only 2 cases had mild decline in carbon monoxide diffusion capacity of predicted (DLCO%pred).Conclusions: We found reduced exercise endurance in all four COVID-19 survivors, even parts of them with normal or slightly abnormal static lung function. We also believe that exercise endurance impairment of COVID-19 convalescents is more likely affected by extrapulmonary factors. Taken the above into consideration, our study highlights that the combination of PFT and CPET are important tests for tracking the development and recovery of COVID-19 survivors.

The incidence, risk factors and prognosis of acute kidney injury in severe and critically ill patients with COVID-19 in mainland China: a retrospective study (preprint)

Background: Since the clinical correlates, prognosis and determinants of AKI in patients with Covid-19 remain largely unclear, we perform a retrospective study to evaluate the incidence, risk factors and prognosis of AKI in severe and critically ill patients with Covid-19.Methods: We reviewed medical records of all adult patients (>18 years) with laboratory-confirmed Covid-19 who were admitted to the intensive care unit (ICU) between January 23rd 2020 and April 6th 2020 at Wuhan JinYinTan Hospital and The First Affiliated Hospital of Guangzhou Medical University. The clinical data, including patient demographics, clinical symptoms and signs, laboratory findings, treatment [including respiratory supports, use of medications and continuous renal replacement therapy (CRRT)] and clinical outcomes, were extracted from the electronic records, and we access the incidence of AKI and the use of CRRT, risk factors for AKI, the outcomes of renal diseases, and the impact of AKI on the clinical outcomes.Results: Among 210 subjects, 131 were males (62.4%). The median age was 64 years (IQR: 56-71). Of 92 (43.8%) patients who developed AKI during hospitalization, 13 (14.1%), 15 (16.3%) and 64 (69.6%) patients were classified as stage 1, 2 and 3, respectively. 54 cases (58.7%) received CRRT. Age, sepsis, Nephrotoxic drug, IMV and elevated baseline Scr were associated with AKI occurrence. The renal recover during hospitalization among 16 AKI patients (17.4%), who had a significantly shorter time from admission to AKI diagnosis, lower incidence of right heart failure and higher P/F ratio. Of 210 patients, 93 patients deceased within 28 days of ICU admission. AKI stage 3, critical disease, greater age and minimum P/F <150mmHg independently associated with it.Conclusions: Among patients with Covid-19, the incidence of AKI was high. age , sepsis, nephrotoxic drug, IMV and baseline Scr were strongly associated with the development of AKI. Time from admission to AKI diagnosis, right heart failure and P/F ratio were independently associated with the potential of renal recovery. Finally, AKI KIDGO stage 3 independently predicted the risk of death within 28 days of ICU admission.