Diaphragm ultrasound evaluation during weaning from mechanical ventilation in COVID-19 patients: a pragmatic, cross-section, multicenter study

Abstract

Background Diaphragmatic dysfunction is a major factor responsible for weaning failure in patients that underwent prolonged invasive mechanical ventilation for acute severe respiratory failure from COVID-19. This study hypothesizes that ultrasound measured diaphragmatic thickening fraction (DTF) could provide corroborating information for weaning COVID-19 patients from mechanical ventilation. Methods This was an observational, pragmatic, cross-section, multicenter study in 6 Italian intensive care units. DTF was assessed in COVID-19 patients undergoing weaning from mechanical ventilation from 1st March 2020 to 30th June 2021. Primary aim was to evaluate whether DTF is a predictive factor for weaning failure. Results Fifty-seven patients were enrolled, 25 patients failed spontaneous breathing trial (44%). Median length of invasive ventilation was 14 days (IQR 7–22). Median DTF within 24 h since the start of weaning was 28% (IQR 22–39%), RASS score (− 2 vs − 2; p = 0.031); Kelly-Matthay score (2 vs 1; p = 0.002); inspiratory oxygen fraction (0.45 vs 0.40; p = 0.033). PaO2/FiO2 ratio was lower (176 vs 241; p = 0.032) and length of intensive care stay was longer (27 vs 16.5 days; p = 0.025) in patients who failed weaning. The generalized linear regression model did not select any variables that could predict weaning failure. DTF was correlated with pH (RR 1.56 × 1027; p = 0.002); Kelly-Matthay score (RR 353; p < 0.001); RASS (RR 2.11; p = 0.003); PaO2/FiO2 ratio (RR 1.03; p = 0.05); SAPS2 (RR 0.71; p = 0.005); hospital and ICU length of stay (RR 1.22 and 0.79, respectively; p < 0.001 and p = 0.004). Conclusions DTF in COVID-19 patients was not predictive of weaning failure from mechanical ventilation, and larger studies are needed to evaluate it in clinical practice further. Registered: ClinicalTrial.gov (NCT05019313, 24 August 2021).

Temporal evolution of diaphragm thickness and diaphragm excursion among subjects hospitalized with COVID-19: A prospective observational study

“…The same group also found that a lower DTF is associated with failure of continuous positive airway pressure leading to invasive mechanical ventilation [18] . On the contrary, an observational study enrolling 57 patients requiring mechanical ventilation for COVID-19 did not find DTF to be a predictive factor for weaning failure [19] . To summarize, these findings highlight that SARS-CoV-2 has an affinity for the diaphragm and underscores the importance of assessment of the diaphragm among subjects with COVID-19.…”

Ultrasonography to Access Diaphragm Dysfunction and Predict the Success of Mechanical Ventilation Weaning in Critical Care

“…39 Some recent studies have reported that reduced DE and DTF were associated with weaning difficulties in patients who are mechanically ventilated, 3,11,31 while others found opposite results. 12,41,42 The most recent studies suggest that diaphragm US enables the prediction of extubation outcome. 28,32,35,45 According to some authors, diaphragmatic movement correlates well with transdiaphragmatic pressure.…”

“…One study included patients with complicated weaning (who had failed previous attempts of SBT) 3 and one study included patients at high risk of extubation failure. 42 Some studies focused exclusively on patients with chronic obstructive pulmonary disease (COPD) 5 or COVID-19 41 or patients whose intubation was due to respiratory causes. 28,29,36,39 This aspect could compromise the applicability of the results due to patient selection.…”

Diaphragm Ultrasound in Critically Ill Patients on Mechanical Ventilation—Evolving Concepts

“…Diaphragmatic dysfunction, defined as excursion < 10 mm or thickening < 30%, was not associated with an increased risk of extubation failure. Vetrugno et al [ 109 ] also demonstrated recently that diaphragm thickening fraction (TF) was not predictive of weaning failure from MV, in 57 COVID-19 patients undergoing weaning from MV.…”