title: Quantitation of regional ventilation during the washout phase of lung scintigraphy: measurement in patients with severe COPD before and after bilateral lung volume reduction surgery.
abstract: OBJECTIVE
  We sought to investigate the effect of lung volume reduction surgery (LVRS) on regional lung ventilation.
  
  
  METHODS
  Retrospective analysis of routinely acquired data before and after LVRS.
  
  
  METHODS
  Large, urban, university medical center.
  
  
  METHODS
  Twenty-nine patients with severe emphysema.
  
  
  METHODS
  Bilateral LVRS.
  
  
  RESULTS
  (133)Xe washout curves during lung scintigraphy exhibit a biphasic pattern (the first component of the washout curve [m(r)] corresponds to an initial rapid phase in washout that reflects larger airways emptying, and the second component [m(s)] reflects a slower phase of washout that is attributed to gas elimination via smaller airways). We analyzed six standardized regions of the lung (upper, mid, and lower zones of the right and left lung), and calculated m(r) and m(s) for each lung region. The mean (+/- SE) baseline FEV(1) was 0.69+/-0.04 L, total lung capacity (TLC) was 139 +/-4% predicted, and the residual volume (RV)/TLC ratio was 65+/-2%. The mean improvement in FEV(1) 3 months post-LVRS was 38%. Post-LVRS, m(r) and m(s) increased in 79 and 74 lung regions, respectively, and there was no relationship with respect to lung regions that had or had not been operated on. The increase in m(s), however, significantly correlated with the increase in FEV(1) (r = 0.66; p<0.0001) and the decrease in RV/TLC (r = -0.67; p<0.0001). An increase in m(s) also correlated with a decrease in PaCO(2) (r = -0.39; p = 0.03), but m(r) showed no relationship with any parameter.
  
  
  CONCLUSIONS
  Small airways ventilation in lung regions that had and had not been operated on is associated with a greater improvement in lung mechanics following LVRS.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Temple University School of Medicine, Philadelphia, PA 19140, USA. trav@astro.ocis.temple.edu
authors.forename: J M
authors.initials: JM
authors.lastname: Travaline
authors.forename: A H
authors.initials: AH
authors.lastname: Maurer
authors.forename: N D
authors.initials: ND
authors.lastname: Charkes
authors.forename: J L
authors.initials: JL
authors.lastname: Urbain
authors.forename: S
authors.initials: S
authors.lastname: Furukawa
authors.forename: G J
authors.initials: GJ
authors.lastname: Criner
mesh_terms: D000280:Administration, Inhalation; D000403:Airway Resistance / Q000502:physiology; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007275:Injections, Intravenous; D008173:Lung Diseases, Obstructive / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology* / Q000601:surgery; D011013:Pneumonectomy; D011379:Prognosis; D012123:Pulmonary Ventilation; D011877:Radionuclide Imaging; D012115:Residual Volume / Q000502:physiology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013438:Sulfhydryl Compounds / Q000008:administration & dosage; D013668:Technetium Tc 99m Aggregated Albumin / Q000008:administration & dosage; D014109:Total Lung Capacity / Q000502:physiology; D014980:Xenon Radioisotopes / Q000008:administration & dosage
chemical_list: D013438:Sulfhydryl Compounds; D013668:Technetium Tc 99m Aggregated Albumin; D014980:Xenon Radioisotopes; C082426:technetium Tc99m-mercaptoacetyl albumin