Functional Respiratory Evaluation in the COVID-19 Era: The Role of Pulmonary Function Test Laboratories

A Delphi consensus statement for the management of post-COVID interstitial lung disease

INTRODUCTION

As millions of people worldwide recover from COVID-19, a substantial proportion continue to have persistent symptoms, pulmonary function abnormalities, and radiological findings suggestive of post-COVID interstitial lung disease (ILD). To date, there is limited scientific evidence on the management of post-COVID ILD, necessitating a consensus-based approach.

AREAS COVERED

A panel of experts in pulmonology and thoracic radiology was constituted. Key questions regarding the management of post-COVID ILD were identified. A search was performed on PubMed and EMBASE and updated till 1 March 2022. The relevant literature regarding the epidemiology, pathophysiology, diagnosis and treatment of post-COVID ILD was summarized. Subsequently, suggestions regarding the management of these patients were framed, and a consensus was obtained using the Delphi approach. Those suggestions which were approved by over 80% of the panelists were accepted. The final document was approved by all panel members.

EXPERT OPINION

Dedicated facilities should be established for the care of patients with post-COVID ILD. Symptom screening, pulmonary function testing, and thoracic imaging have a role in the diagnosis. The pharmacologic and non-pharmacologic options for the management of post-COVID ILD are discussed. Further research into the pathophysiology and management of post-COVID ILD will improve our understanding of this condition.

Small airway dysfunction on impulse oscillometry and pathological signs on lung ultrasound are frequent in post-COVID-19 patients with persistent respiratory symptoms

Background

Thousands of people worldwide are suffering the consequences of coronavirus disease-2019 (COVID-19), and impulse oscillometry (IOS) and lung ultrasound (LUS) might be important tools for the follow-up of this population. Our objective was to prospectively evaluate abnormalities detected using these two methods in a cohort of COVID-19 survivors with respiratory symptoms.

Methods

In this follow-up study, 59 patients underwent clinical evaluations, spirometry, IOS and LUS in the 2nd (M1) and 5th (M2) months after diagnostic confirmation of COVID-19 by real-time reverse transcriptase–polymerase chain reaction. Aeration scores were obtained from the LUS exams based on the following findings: B-lines >2, coalescent B-lines, and subpleural consolidations.

Results

Fifty-nine (100%) participants had cough and/or dyspnea at M1, which decreased to 38 (64.4%) at M2 (p = 0.0001). Spirometry was abnormal in 26 (44.1%) and 20 (33.9%) participants at M1 and M2, respectively, although without statistical significance (p = 0.10). Normal examination, restrictive patterns, and obstructive patterns were observed in 33 (55.9%), 18 (30.5%), and 8 (13.6%) participants, respectively, at M1 and in 39 (66.1%), 13 (22%), and 7 (11.9%) participants at M2 (p = 0.14). Regarding IOS, considering changes in resistive and reactive parameters, abnormal exams were detected in 52 (88.1%) and 42 (71.2%) participants at M1 and M2, respectively (p = 0.002). Heterogeneity of resistance between 4 and 20 Hz >20% was observed in 38 (64.4%) and 33 (55.9%) participants at M1 and M2, respectively (p = 0.30). Abnormal LUS was observed in 46 (78%) and 36 (61%) participants at M1 and M2, respectively (p = 0.002), with a reduction in aeration scores between M1 and M2 [5 (2–8) vs. 3 (0–6) points, p<0.0001].

Conclusions

IOS and LUS abnormalities are frequent in the first 5 months post-COVID-19 infection; however, when prospectively evaluated, significant improvement is evident in the parameters measured by these two methods.

Pediatric Pulmonary Function Testing in COVID-19 Pandemic and Beyond. A Position Statement From the Hellenic Pediatric Respiratory Society

As the COVID-19 pandemic is still evolving, guidelines on pulmonary function testing that may dynamically adapt to sudden epidemiologic changes are required. This paper presents the recommendations of the Hellenic Pediatric Respiratory Society (HPRS) on pulmonary function testing in children and adolescents during the COVID-19 era. Following an extensive review of the relevant literature, we recommend that pulmonary function tests should be carried out after careful evaluation of the epidemiologic load, structured clinical screening of all candidates, and application of special protective measures to minimize the risk of viral cross infection. These principles have been integrated into a dynamic action plan that may readily adapt to the phase of the pandemic.