Lung ultrasound findings following COVID-19 hospitalization: A prospective longitudinal cohort study

Implementation of an International Severe Infection Point-of-Care Ultrasound Research Network

INTRODUCTION

Point-of-care ultrasound (POCUS) is a rapid, readily available, and cost-effective diagnostic and prognostic modality in a range of clinical settings. However, data to support its clinical application are limited. This project's main goal was to assess the effectiveness of standardizing lung ultrasound (LUS) training for sonographers to determine if universal LUS adoption is justified.

MATERIALS AND METHODS

We describe the effectiveness of an implementation of a LUS research training program across eight international study sites in Asia, Africa, and North America as part of prospective Coronavirus Disease of 2019 (COVID-19) and sepsis study cohorts (Rapid Assessment of Infection with SONography research network). Within our network, point-of-care LUS was used to longitudinally evaluate radiographic markers of lung injury. POCUS operators were personnel from a variety of backgrounds ranging from research coordinators with no medical background to experienced clinicians.

RESULTS

Following a standardized protocol, 49 study sonographers were trained and LUS images from 486 study participants were collected. After training was completed, we compared before and after image qualities for interpretation. The proportion of acceptable images improved at each site between the first 25 scans and the second 25 scans, resulting in 80% or greater acceptance at each study site.

CONCLUSIONS

POCUS training and implementation proved feasible in diverse research settings among a range of providers. Standardization across ongoing cohort protocols affords opportunities for increased statistical power and generalizability of results. These results potentially support care delivery by enabling military medics to provide care at the point of injury, as well as aiding frontline clinicians in both austere and highly resourced critical care settings.

The Role of POCUS to Face COVID-19: A Narrative Review

COVID-19 has been a challenging outbreak to face, with millions of deaths among the globe. Acute respiratory failure due to interstitial pneumonia was the leading cause of death other than prothrombotic activation and complications. Lung ultrasound (LUS) and point-of-care ultrasound (POCUS) are widely used not only to triage, to identify, and to monitor lungs involvement but also to assess hemodynamic status and thrombotic and hemorrhagic complications, mainly in critically ill patients. POCUS has gained growing consideration due to its bedside utilization, reliability, and reproducibility even in emergency settings especially in unstable patients. In this narrative review, we aim to describe LUS and POCUS utilization in COVID-19 infection based on the literature found on this topic. We reported the LUS patterns of COVID-19 pulmonary infection, the diagnostic accuracy with respect to CT lung scan, its prognostic value, the variety of scores and protocols proposed, and the utilization of POCUS to investigate the extra-lung complications.

Thoracic ultrasonographic and clinical findings at 12-month follow-up of patients admitted with COVID-19

Introduction

Thoracic ultrasound (TUS) has proven useful in the diagnosis, risk stratification and monitoring of disease progression in patients with coronavirus disease 2019 (COVID-19). However, utility in follow-up is poorly described. To elucidate this area, we performed TUS as part of a 12-month clinical follow-up in patients previously admitted with COVID-19 and correlated findings with clinical assessment and pulmonary function tests.

Methods

Adult patients discharged from our hospital following admission with COVID-19 during March to May 2020 were invited to a 12-month follow-up. Enrolled patients were interviewed regarding persisting or newly developed symptoms in addition to TUS, spirometry and a 6-min walk test. Patients were referred to high-resolution computed tomography (HRCT) of the lungs if suspicion of pulmonary fibrosis was raised.

Results

Forty patients were enrolled in the study of whom had 13 developed acute respiratory distress syndrome (ARDS) during admission. Patients with ARDS were more prone to experience neurological symptoms at follow-up (p = 0.03) and showed more B-lines on TUS (p = 0.008) but did not otherwise differ significantly in terms of pulmonary function tests. Four patients had pathological findings on TUS where subsequent diagnostics revealed that two had interstitial lung abnormalities and two had heart failure. These four patients presented with a significantly lower diffusing capacity of lung for carbon monoxide (p=0.03) and 6-min walking distance (p=0.006) compared to the remaining 36 patients without ultrasound pathology. No significant difference was observed in spirometry values of % of predicted FEV1 (p=0.49) or FVC (p=0.07). No persisting cardiovascular pathology was observed in patients without ultrasonographic pathology.

Conclusion

At 12-month after admission with COVID-19, a follow-up combining TUS, clinical assessment, and pulmonary function tests may improve the selection of patients requiring further diagnostic investigations such as HRCT or echocardiography.

Point-of-Care Ultrasound of Post-acute COVID-19 Syndrome: A Prospective Cohort Study

Introduction Acute COVID-19 patients can suffer from chronic symptoms known as post-acute sequelae of SARS-CoV-2 infection (PASC). Point-of-care ultrasound (POCUS) is established in acute COVID, but its utility in PASC is unclear. We sought to determine the incidence of cardiac and pulmonary abnormalities with POCUS in patients with PASC in a COVID-19 recovery clinic. Methods This prospective cohort study included adults (>18 years old) presenting with cardiopulmonary symptoms to the COVID-19 recovery clinic. A lung ultrasound and standard bedside echocardiogram were performed by ultrasound-trained physicians. Images were interpreted in real time by the performing sonographer and independently by a blinded ultrasound faculty member. Discrepancies in interpretation were addressed by consensus review. A modified Soldati score was calculated by the sum of the scores in each of the 12 lung zones, with each zone score ranging from 0 to 3 (maximum score of 36). The score was then compared to clinical outcomes and outpatient testing.  Results Between April and July 2021, 41 patients received POCUS examinations, with 24 of those included in the study. In all, 15 out of 24 (62.5%) had a normal lung ultrasound. Of the nine subjects with lung abnormalities, the median modified Soldati score was 2. Three patients had trivial pericardial effusions, and all had normal left and right ventricular size and function. Conclusion The majority (62.5%) of patients presenting to the PASC clinic had a normal pulmonary ultrasound, and the vast majority (87.5%) had normal cardiac ultrasounds. These findings suggest that cardiopulmonary symptoms in PASC may be from etiologies not well evaluated by POCUS.

One-Year Follow-Up Lung Ultrasound of Post-COVID Syndrome-A Pilot Study

(1) Background: Millions of people worldwide were infected with COVID-19. After the acute phase of the disease, many suffer from prolonged symptoms, the post-COVID syndrome, especially the phenotype with lung residuals. Many open questions regarding lung ultrasound (LUS) have to be answered. One essential question is the means for optimal following-up of patients with post-COVID-19 residuals with LUS; (2) Methods: A retrospective data analysis of patients after acute COVID-19 infection diagnosed with post-COVID syndrome in the state hospital of Steyr and the rehabilitation center of Hochegg was performed. LUS examinations following a 12-zone scanning protocol were performed, and the LUS score quantified comet tail artifacts. A total of 16 patients were evaluated twice with LUS from May 2020 until June 2021. (3) Results: All patients’ reverberation artifacts were reduced over time. The initial LUS score of 17.75 (SD 4.84) points was decreased over the duration of the second rehabilitation to 8,2 (SD 5.94). The difference in the Wilcoxon test was significant (p < 0.001); (4) Conclusions: Lung ultrasound was a valuable tool in the follow-up of post-COVID-syndrome with lung residuals in the first wave of COVID-19. A reduction in reverberation artifacts was demonstrated. Further studies about the clinical significance have to follow.

Do worsening lung ultrasound scans identify severe COVID-19 trajectories?

Background

While point-of-care ultrasound (POCUS) has been used to track worsening COVID-19 disease it is unclear if there are dynamic differences between severity trajectories.

Methods

We studied 12-lung zone protocol scans from 244 participants [with repeat scans obtained in 3 days (N = 114), 7 days (N = 53), and weekly (N = 9)] ≥ 18 years of age hospitalized for COVID-19 pneumonia. Differences in mean lung ultrasound (LUS) scores and percent of lung fields with A-lines over time were compared between peak severity levels (as defined by the WHO clinical progression scale) using linear mixed-effects models.

Results

Mean LUS scores were elevated by 0.19 (p = 0.035) and A-lines were present in 14.7% fewer lung fields (p = 0.02) among those with ICU-level or fatal peak illness compared to less severe hospitalized illness, regardless of duration of illness. There were no differences between severity groups in the trajectories of mean LUS score 0.19 (p = 0.66) or percent A-lines (p = 0.40).

Discussion

Our results do not support the use of serial LUS scans to monitor COVID-19 disease progression among hospitalized adults.

Usefulness of C2HEST Score in Predicting Clinical Outcomes of COVID-19 in Heart Failure and Non-Heart-Failure Cohorts

Background: Patients with heart failure represent a vulnerable population for COVID-19 and are prone to having worse prognoses and higher fatality rates. Still, the clinical course of the infection is dynamic, and complication occurrence in particular in patients with heart failure is fairly unpredictable. Considering that individual components of the C2HEST (C2: Coronary Artery Diseases (CAD)/Chronic obstructive pulmonary disease (COPD); H: Hypertension; E: Elderly (Age ≥ 75); S: Systolic HF; T: Thyroid disease) are parallel to COVID-19 mortality risk factors, we evaluate the predictive value of C2HEST score in patients with heart failure (HF) Material and Methods: The retrospective medical data analysis of 2184 COVID-19 patients hospitalized in the University Hospital in Wroclaw between February 2020 and June 2021 was the basis of the study. The measured outcomes included: in-hospital mortality, 3-month and 6-month all-cause-mortality, non-fatal end of hospitalization, and adverse in-hospital clinical events. Results: The heart failure cohort consists of 255 patients, while 1929 patients were assigned to the non-HF cohort. The in-hospital, 3-month, and 6-month mortality rates were highest in the HF cohort high-risk C2HEST stratum, reaching 38.61%, 53.96%, and 65.36%, respectively. In the non-HF cohort, in-hospital, 3-month, and 6-month mortalities were also highest in the high-risk C2HEST stratum and came to 26.39%, 52.78%, and 65.0%, respectively. An additional point in the C2HEST score increased the total death intensity in 10% of HF subjects (HR 1.100, 95% CI 0.968−1.250 p = 0.143) while in the non-HF cohort, the same value increased by 62.3% (HR 1.623, 95% CI 1.518−1.734 p < 0.0001). Conclusions: The C2HEST score risk in the HF cohort failed to show discriminatory performance in terms of mortality and other clinical adverse outcomes during hospitalization. C2HEST score in the non-HF cohort showed significantly better performance in terms of predicting in-hospital and 6-month mortality and other non-fatal clinical outcomes such as cardiovascular events (myocardial injury, acute heart failure, myocardial infarction, cardiogenic shock), pneumonia, sepsis, and acute renal injury.