TY - JOUR T1 - Sonographic follow-up of diaphragm function in COVID-19: an exploratory study JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00623-2022 SP - 00623-2022 AU - Carlijn Veldman AU - Wytze S. de Boer AU - Huib A.M. Kerstjens AU - Mireille A. Edens AU - Jan Willem K. van den Berg Y1 - 2023/01/01 UR - http://openres.ersjournals.com/content/early/2023/02/23/23120541.00623-2022.abstract N2 - Introduction Survivors of COVID-19 frequently endure chronic disabilities. We hypothesize that diaphragm function has a long recovery time after COVID-19 hospitalization, and may play a role in post-COVID syndrome. The aim of this study was to assess diaphragm function during COVID-19 hospitalization and during recovery.Methods We conducted a prospective single-center cohort study in 49 patients enrolled, of which 28 completed one-year follow-up. Participants were evaluated for diaphragm function. Diaphragm function was assessed using ultrasound measuring of diaphragm thickening fraction (TF) within 24 h after admission, after 7 days of admission or at discharge, whichever came first, and three and twelve months after hospital admission.Results Estimated mean TF increased from 0.56 (95% CI 0.46–0.66) on admission to 0.78 (95% CI 0.65–0.89) at discharge or seven days after admission, to 1.05 (95% CI 0.83–1.26) three months after admission to 1.54 (95% CI 1.31–1.76) twelve months after admission. The improvements from admission to discharge, 3 months and 12 months were all significant (linear mixed modeling; p=0.020, p<0.001, and p<0.001, respectively) and the improvement from discharge to three months follow-up was borderline significant (p<0.1).Conclusion Diaphragm function was impaired during hospitalization for COVID-19. During recovery in hospital and up to one-year follow-up, diaphragm TF improved, suggesting a long recovery time of the diaphragm. Diaphragm ultrasound may be a valuable modality in the screening and follow-up of (post-)COVID-19 patients for diaphragm dysfunction.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: The listed authors declare that there is no conflict of interest. ER -