title: Regional distribution of lung compliance by image analysis of computed tomograms.
abstract: Computed tomography (CT) can yield quantitative information about volume distribution in the lung. By combining information provided by CT and respiratory mechanics, this study aims at quantifying regional lung compliance (CL) and its distribution and homogeneity in mechanically ventilated pigs. The animals underwent inspiratory hold maneuvers at 12 lung volumes with simultaneous CT exposure at two end-expiratory pressure levels and before and after acute lung injury (ALI) by oleic acid administration. CL and the sum of positive voxel compliances from CT were linearly correlated; negative compliance areas were found. A remarkably heterogeneous distribution of voxel compliance was found in the injured lungs. As the lung inflation increased, the homogeneity increased in healthy lungs but decreased in injured lungs. Image analysis brought novel findings regarding spatial homogeneity of compliance, which increases in ALI but not in healthy lungs by applying PEEP after a recruitment maneuver.
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy; Medical Sciences - Clinical Physiology, Uppsala University, Uppsala, Sweden. Electronic address: gaetano.perchiazzi@uniba.it.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Perchiazzi
authors.affiliation: Anaesthesia and Intensive Care Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Rylander
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Savino
authors.initials: S
authors.lastname: Derosa
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Mariangela
authors.initials: M
authors.lastname: Pellegrini
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Loredana
authors.initials: L
authors.lastname: Pitagora
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Debora
authors.initials: D
authors.lastname: Polieri
authors.affiliation: Intensive Care Unit, SS Annunziata Hospital, Taranto, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Vena
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Tannoia
authors.affiliation: Emergency and Organ Transplant, Bari University, Bari, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Fiore
authors.affiliation: Medical Sciences - Clinical Physiology, Uppsala University, Uppsala, Sweden.
authors.forename: Göran
authors.initials: G
authors.lastname: Hedenstierna
mesh_terms: D055371:Acute Lung Injury / Q000139:chemically induced / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D003198:Computer Simulation; D004195:Disease Models, Animal; D008168:Lung / Q000000981:diagnostic imaging* / Q000502:physiology*; D008170:Lung Compliance / Q000502:physiology; D019301:Oleic Acid / Q000633:toxicity; D012119:Respiration; D015656:Respiratory Mechanics / Q000502:physiology*; D013552:Swine; D014057:Tomography, X-Ray Computed
chemical_list: D019301:Oleic Acid
keywords: Acute lung injury; Computed tomography; Image registration; Lung compliance; Mechanical ventilation