RT Journal Article
SR Electronic
T1 M-mode obstruction index (MIO): an ultrasound method to evaluate presence and severity of airway obstruction in COPD patient
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 1294
DO 10.1183/13993003.congress-2022.1294
VO 60
IS suppl 66
A1 E Riccardi
A1 M Comune
A1 G Ferrari
A1 A Oliva
A1 P Righini
A1 V Gallo
A1 C Geninatti
A1 R Prota
YR 2022
UL http://erj.ersjournals.com/content/60/suppl_66/1294.abstract
AB Introduction: MIO is an ultrasound index obtained from the ratio between the diaphragmatic excursion during the first second of a forced expiration (FEDE1, cm) and the total expiratory excursion (EDEmax, cm). Zanforlin et al showed that a MIO below 77% may discriminate patients with airway obstruction from healthy subjects.Aims and objectives: To confirm the validity of MIO in detecting airway obstruction and to assess its sensitivity in identifying the severity of the obstruction.Methods: Spirometry and M-MODE diaphragmatic ultrasound were performed in 21 subjects with normal spirometry (group A) and in 38 COPD patients (group B), 18 GOLD 1-2 (group B1) and 20 GOLD 3-4 (group B2). FEDE1, EDEmax and their percent ratio (MIO) were calculated during a maximal forced open-mouth expiration. The median value of 3 repeated measurements was used for the analysis.Results: ANOVA showed that MIO was higher (p<0.05) in group A (88±6.9%) than in group B (59±12%) and in group B1 (69±4%) than in B2 (50±10%). In all subjects MIO was related to FEV1 %pred (r=0,79,p<0.001). ROC analysis showed that the optimal MIO cut-off to discriminate airway obstruction (FEV1/VC<70%) was 73.5% (AUC 0.98,p<0.01,sensitivity 94,7%,specificity 95%) while the cut-off to discriminate B2 (FEV1<50%) from B1 group was 60.9% (AUC 0,93,p<0.01,sensitivity 95%,specificity 94,4%).Conclusions: MIO is a good index to detect airway obstruction and it’s closely related to FEV1. We identified a MIO cut-off value for airway obstruction of 73.5% (similar to the 77% previously proposed) and we found that a MIO of 60.9% can discriminate patients with severe from those with mild-moderate airway obstruction.FootnotesCite this article as Eur Respir J 2022; 60: Suppl. 66, 1294.This article was presented at the 2022 ERS International Congress, in session “-”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).