PT  - JOURNAL ARTICLE
AU  - Alessandro Zanforlin
AU  - Andrea Smargiassi
AU  - Riccardo Inchingolo
AU  - Alessandro di Marco Berardino
AU  - Emilio Ramazzina
TI  - Ultrasound analysis of the effect of airways obstruction on diaphragm relaxation pattern
DP  - 2013 Sep 01
TA  - European Respiratory Journal
PG  - P1929
VI  - 42
IP  - Suppl 57
4099  - http://erj.ersjournals.com/content/42/Suppl_57/P1929.short
4100  - http://erj.ersjournals.com/content/42/Suppl_57/P1929.full
SO  - Eur Respir J2013 Sep 01; 42
AB  - Diaphragm motion can be analysed with ultrasound using M-mode in anterior subcostal approach (Testa, A et al. Ultrasound Med Biol 2011;37:44-52). The diaphragm line during a forced expiration shows an initial drop off followed by a plateau in maximum expiration. Maximum expiratory diaphragmatic excursion (EDEMax) and forced expiratory diaphragmatic excursion in the first second (FEDE1) can be measured and considered as phisiopathological analogues of vital capacity (VC) and FEV1.As the ratio FEV1/VC% is used as a marker of obstruction, the aim of our study was to assess if the ratio FEDE1/EDEMax% (M-mode Index of Obstruction [MIO]) is different between normal subjects and patients with obstructive spirometric pattern (Miller, MR. Eur Respir J. 2005;26:319-38).4 operators in 2 centers examined with ultrasound the diaphragmatic motion of outpatients with known spirometric pattern using M-mode during a maximal forced expiration in semi supine position. FEDE1 and EDEMax were recorded and MIO calculated.124 patients were examined, 61 normal and 63 obstructed. MIO values: in normal group 72.84 to 100, mean 87.08±6.64, median 87.21; in obstructed group 33.33 to 91.30, mean 67.09±12.49, median 70.48. MIO values of the two groups showed a minimum overlap and a significant difference (p<0.0001), suggesting that ultrasound could potentially detect airway obstruction by analysing diaphragm kinetics. MIO can be interpreted as a speed index of diaphragmatic relaxation that seems to be slower in obstructed patients.Ultrasound analysis of diaphragmatic motion could potentially identify an obstructive pattern, being a potential add-on screening technique for detecting airways obstruction.