title: Clinical application of inert gas Multiple Breath Washout in children and adolescents with asthma.
abstract: BACKGROUND
  Children with asthma often have normal spirometry despite significant disease. The pathology of the small airways in asthma may be assessed using Multiple Breath Washout (MBW) and calculating the Lung Clearance Index (LCI). There are only few studies using MBW in children with asthma and existing data regarding bronchodilator effect are contradictory. The aim of the present pilot study was to compare LCI in asthma and controls and assess the effect of salbutamol in children with asthma on the LCI.
  
  
  METHODS
  Unselected patients with a diagnosis of asthma visiting the outpatient department of our hospital between 04-2010 and 03-2011 were recruited and compared to a healthy control group. MBW was performed as inert gas MBW using sulfurhexafluorid (SF6) as the tracer gas. Clinical data were documented and spirometry and MBW (EasyOne Pro, MBW module, NDD Switzerland) were performed before and after the use of salbutamol (200-400 μg). Healthy controls performed baseline MBW only.
  
  
  RESULTS
  32 children diagnosed with asthma (4.7-17.4 years) and 42 controls (5.3-20.8) were included in the analysis. LCI differed between patients and controls, with a mean LCI (SD) of 6.48 (0.48) and 6.21 (0.38) (P = 0.008). Use of salbutamol had no significant effect on LCI for the group.
  
  
  CONCLUSIONS
  These pilot data show that clinically stable asthma patients and controls both have a LCI in the normal range. However, in patients the LCI is significantly higher indicating that MBW may have a role in assessing small airways disease in asthma.
authors.affiliation: Marien Hospital Wesel, Department of Paediatrics and Research Institute, Germany; Radboud University Medical Centre, Department of Paediatrics, Nijmegen, The Netherlands. Electronic address: anneliesmaria.zwitserloot@prohomine.de.
authors.forename: Annelies
authors.initials: A
authors.lastname: Zwitserloot
authors.affiliation: Marien Hospital Wesel, Department of Paediatrics and Research Institute, Germany.
authors.forename: Susanne I
authors.initials: SI
authors.lastname: Fuchs
authors.affiliation: Marien Hospital Wesel, Department of Paediatrics and Research Institute, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Müller
authors.affiliation: Marien Hospital Wesel, Department of Paediatrics and Research Institute, Germany.
authors.forename: Kornelia
authors.initials: K
authors.lastname: Bisdorf
authors.affiliation: Marien Hospital Wesel, Department of Paediatrics and Research Institute, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Gappa
mesh_terms: D000293:Adolescent; D058666:Adrenergic beta-2 Receptor Agonists / Q000627:therapeutic use; D000420:Albuterol / Q000627:therapeutic use; D001249:Asthma / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D001944:Breath Tests / Q000379:methods; D001993:Bronchodilator Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D010865:Pilot Projects; D013147:Spirometry / Q000379:methods; D055815:Young Adult
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents; D000420:Albuterol
keywords: Asthma; Children; Multiple Breath Washout; SF(6); Ultrasonic flow sensor