title: Influence of change in lateral decubitus on pulmonary aerosol deposition.
abstract: BACKGROUND
  The lateral decubitus position leads to the greatest changes in regional pulmonary ventilation and is used in respiratory physical therapy routines.
  
  
  OBJECTIVE
  To evaluate the influence of the lateral decubitus position on the pulmonary deposition of inhaled radioaerosol particles in young people and report the effects of the decubitus position on routine therapy.
  
  
  METHODS
  Eight healthy male volunteers, mean age 23.6±2.5 years, were included in a randomized study in two phases. In the first phase, aerosol was inhaled for nine minutes in a randomly-selected lateral decubitus position and after an interval of 5 to 7 days, the second phase was conducted. Pulmonary scintigraphy was carried out by inhalation of 25 mCi of 99mTc-DTPA. Following inhalation, images were acquired with scintillation cameras and regions of interest (ROI) were investigated in the longitudinal and cross-sectional divisions of the lungs. Statistical analysis included a paired Student's t-test with a significance level of p≤0.05.
  
  
  RESULTS
  Inhalation in the right lateral decubitus position presented higher counts (p≤0.04) in posterior ROI of the right lung than in the posterior ROI of the left lung. In the left lateral decubitus position, the count was higher in the left lung (p≤0.02) than in the posterior ROI of the right lung.
  
  
  CONCLUSIONS
  The deposition of aerosol particles during inhalation was position-dependent in the two phases of the study, which confirms the validity of technical and therapeutic resources based on the physiology of position-dependent ventilation and suggests that body positioning can be used to advantage in routine therapy.
authors.affiliation: Laboratory of Cardiorespiratory Physical Therapy, Physical Therapy Department, Universidade Federal de Pernambuco, Recife, PE, Brasil. lucalcoforado@yahoo.com.br
authors.forename: Luciana
authors.initials: L
authors.lastname: Alcoforado
authors.forename: Luiz C
authors.initials: LC
authors.lastname: Pessôa Filho
authors.forename: Daniella C
authors.initials: DC
authors.lastname: Brandão
authors.forename: André M
authors.initials: AM
authors.lastname: Galvão
authors.forename: Cyda M A
authors.initials: CM
authors.lastname: Reinaux
authors.forename: Armèle Dornelas de
authors.initials: AD
authors.lastname: Andrade
mesh_terms: D000336:Aerosols / Q000378:metabolism*; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male; D056888:Patient Positioning / Q000379:methods; D055815:Young Adult
chemical_list: D000336:Aerosols