Changes in the Lung Clearance Index in Pediatric Patients With Asthma

Summary

The multiple breath washout (MBW) is one of pulmonary function test that displays flow and gas concentration plotted against time, and shows an exponential decay in end-tidal gas concentration (washout curve). A number of of indices to describe the washout curve have been proposed, the most commonly reported is the Lung Clearance Index (LCI). This is a simple measure of ventilation heterogeneity derived from MBW, that can be used after challenge with a short action bronchodilator and in response to inhaled steroids, both in the conductive airways as acinar. Patients with moderate and severe asthma are characterized by an abnormality in both, conductive and the acinar airway. Therefore the following research question could be: what are the abnormalities in the heterogeneity of ventilation in children with mild and moderate asthma, with respect to the healthy population measured by MBW, and whether these alterations persist after challenge with inhaled steroids and B2 agonists short-acting.

Timeline

Start

2016-03

Primary completion

2016-08

Completion

2016-12

Publications

• Background Downie SR, Salome CM, Verbanck S, Thompson B, Berend N, King GG. Ventilation heterogeneity is a major determinant of airway hyperresponsiveness in asthma, independent of airway inflammation. Thorax. 2007 Aug;62(8):684-9. doi: 10.1136/thx.2006.069682. Epub 2007 Feb 20.
• Background Martin RJ. Therapeutic significance of distal airway inflammation in asthma. J Allergy Clin Immunol. 2002 Feb;109(2 Suppl):S447-60. doi: 10.1067/mai.2002.121409.
• Background Tulic MK, Christodoulopoulos P, Hamid Q. Small airway inflammation in asthma. Respir Res. 2001;2(6):333-9. doi: 10.1186/rr83. Epub 2001 Aug 10.
• Background Enright PL, Lebowitz MD, Cockroft DW. Physiologic measures: pulmonary function tests. Asthma outcome. Am J Respir Crit Care Med. 1994 Feb;149(2 Pt 2):S9-18; discussion S19-20. doi: 10.1164/ajrccm/149.2_Pt_2.S9.
• Background Ruppel GL, Enright PL. Pulmonary function testing. Respir Care. 2012 Jan;57(1):165-75. doi: 10.4187/respcare.01640.
• Background Pellegrino R, Viegi G, Brusasco V, Crapo RO, Burgos F, Casaburi R, Coates A, van der Grinten CP, Gustafsson P, Hankinson J, Jensen R, Johnson DC, MacIntyre N, McKay R, Miller MR, Navajas D, Pedersen OF, Wanger J. Interpretative strategies for lung function tests. Eur Respir J. 2005 Nov;26(5):948-68. doi: 10.1183/09031936.05.00035205. No abstract available.
• Background Verbanck S, Schuermans D, Van Muylem A, Melot C, Noppen M, Vincken W, Paiva M. Conductive and acinar lung-zone contributions to ventilation inhomogeneity in COPD. Am J Respir Crit Care Med. 1998 May;157(5 Pt 1):1573-7. doi: 10.1164/ajrccm.157.5.9710042.
• Background Tashkin DP. The role of small airway inflammation in asthma. Allergy Asthma Proc. 2002 Jul-Aug;23(4):233-42.
• Background Timmins SC, Diba C, Farrow CE, Schoeffel RE, Berend N, Salome CM, King GG. The relationship between airflow obstruction, emphysema extent, and small airways function in COPD. Chest. 2012 Aug;142(2):312-319. doi: 10.1378/chest.11-2169.
• Background Verbanck S, Schuermans D, Paiva M, Vincken W. The functional benefit of anti-inflammatory aerosols in the lung periphery. J Allergy Clin Immunol. 2006 Aug;118(2):340-6. doi: 10.1016/j.jaci.2006.04.056. Epub 2006 Jun 21.
• Background Verbanck S, Thompson BR, Schuermans D, Kalsi H, Biddiscombe M, Stuart-Andrews C, Hanon S, Van Muylem A, Paiva M, Vincken W, Usmani O. Ventilation heterogeneity in the acinar and conductive zones of the normal ageing lung. Thorax. 2012 Sep;67(9):789-95. doi: 10.1136/thoraxjnl-2011-201484. Epub 2012 Apr 27.
• Background Macleod KA, Horsley AR, Bell NJ, Greening AP, Innes JA, Cunningham S. Ventilation heterogeneity in children with well controlled asthma with normal spirometry indicates residual airways disease. Thorax. 2009 Jan;64(1):33-7. doi: 10.1136/thx.2007.095018. Epub 2008 Aug 4.
• Background Verbanck S, Schuermans D, Paiva M, Vincken W. Nonreversible conductive airway ventilation heterogeneity in mild asthma. J Appl Physiol (1985). 2003 Apr;94(4):1380-6. doi: 10.1152/japplphysiol.00588.2002. Epub 2002 Dec 6.
• Background Verbanck S, Schuermans D, Vincken W. Inflammation and airway function in the lung periphery of patients with stable asthma. J Allergy Clin Immunol. 2010 Mar;125(3):611-6. doi: 10.1016/j.jaci.2009.10.053. Epub 2010 Feb 4.
• Background Horsley A. Lung clearance index in the assessment of airways disease. Respir Med. 2009 Jun;103(6):793-9. doi: 10.1016/j.rmed.2009.01.025. Epub 2009 Feb 25.
• Background Singer F, Abbas C, Yammine S, Casaulta C, Frey U, Latzin P. Abnormal small airways function in children with mild asthma. Chest. 2014 Mar 1;145(3):492-499. doi: 10.1378/chest.13-0784.

Drugs

Indications