title: The effects of direct hemoperfusion using a polymyxin B-immobilized column in a pig model of severe Pseudomonas aeruginosa pneumonia.
abstract: BACKGROUND
  Hemoperfusion through a column containing polymyxin B-immobilized fiber (PMX-HP) is beneficial in abdominal sepsis. We assessed the effects of PMX-HP in a model of severe Pseudomonas aeruginosa pneumonia.
  
  
  METHODS
  Eighteen pigs with severe P. aeruginosa pneumonia were mechanically ventilated for 76 h. Pigs were randomized to receive standard treatment with fluids and vasoactive drugs, or standard treatment with two 3-h PMX-HP sessions. Antibiotics against P. aeruginosa were never administered. We assessed endotoxemia through the endotoxin activity assay (EA). We measured the static lung elastance, ratio of arterial partial pressure per inspiratory fraction of oxygen (PaO2/FIO2), mean arterial pressure, cardiac output, systemic vascular resistance and inotropic score. Finally, every 24 h, we assessed complete blood count.
  
  
  RESULTS
  In comparison with the control group, PMX-HP decreased percentage of circulating neutrophils from 47.4 ± 13.8 to 40.8 ± 11.5 % (p = 0.009). In a subgroup of animals with the worst hemodynamic impairment, EA in the control and PMX-HP groups was 0.50 ± 0.29 and 0.29 ± 0.14, respectively (p = 0.018). Additionally, in the control and PMX-HP groups, static lung elastance was 26.9 ± 8.7 and 25.3 ± 7.5 cm H2O/L (p = 0.558), PaO2/FIO2 was 347.3 ± 61.9 and 356.4 ± 84.0 mmHg (p = 0.118), mean arterial pressure was 81.2 ± 10.3 and 81.6 ± 13.1 mmHg (p = 0.960), cardiac output was 3.30 ± 1.11 and 3.28 ± 1.19 L/min (p = 0.535), systemic vascular resistance was 1982.6 ± 608.4 and 2011.8 ± 750.0 dyne/s/cm(-5) (p = 0.939), and inotropic score was 0.25 ± 0.10 and 0.26 ± 0.18 (p = 0.864).
  
  
  CONCLUSIONS
  In mechanically ventilated pigs with severe P. aeruginosa pneumonia, PMX-HP does not have any valuable clinical benefit, and studies are warranted to fully evaluate a potential role of PMX-HP in septic shock associated with severe pulmonary infections.
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.|University of Barcelona, Barcelona, Spain.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Li Bassi
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.
authors.forename: Joan Daniel
authors.initials: JD
authors.lastname: Marti
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.
authors.forename: Eli Aguilera
authors.initials: EA
authors.lastname: Xiol
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Talitha
authors.initials: T
authors.lastname: Comaru
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|University of Milan, Milan, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: De Rosa
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Rigol
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|University of Milan, Milan, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Terraneo
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.
authors.forename: Mariano
authors.initials: M
authors.lastname: Rinaudo
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.|University of Barcelona, Barcelona, Spain.|Research Laboratory, Department of Pulmonary and Critical Care Medicine, Hospital Clinic, Barcelona, Spain.
authors.forename: Laia
authors.initials: L
authors.lastname: Fernandez
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain.|University of Barcelona, Barcelona, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ferrer
authors.affiliation: Division of Animal Experimentation, Department of Pulmonary and Critical Care Medicine, Thorax Institute, Hospital Clínic, Barcelona, Spain. atorres@clinic.ub.es.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain. atorres@clinic.ub.es.|Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Majorca, Spain. atorres@clinic.ub.es.|University of Barcelona, Barcelona, Spain. atorres@clinic.ub.es.
authors.forename: Antoni
authors.identifier: http://orcid.org/0000-0002-5649-7699
authors.initials: A
authors.lastname: Torres
keywords: Complications—septicemia; Infection—bacterial; Intensive care—pulmonary; Lung—endotoxemia