title: Intermittent positive pressure ventilation increases diastolic pulmonary arterial pressure in advanced COPD.
abstract: OBJECTIVE
  To measure the impact of intermittent positive pressure ventilation (IPPV) on diastolic pulmonary arterial pressure (dPAP) and pulmonary pulse pressure in patients with advanced COPD.
  
  
  BACKGROUND
  The physiological effects of raised intrathoracic pressures upon the pulmonary circulation have not been fully established.
  
  
  METHODS
  22 subjects with severe COPD receiving IPPV were prospectively assessed with pulmonary and radial arterial catheterization. Changes in dPAP were assessed from end-expiration to early inspiration during low and high tidal volume ventilation.
  
  
  RESULTS
  Inspiration during low tidal volume IPPV increased the median [IQR] dPAP by 3.9 [2.5-4.8] mm Hg (P < 0.001). During high tidal volume, similar changes were observed. The IPPV-associated change in dPAP was correlated with baseline measures of PaO2 (rho = 0.65, P = 0.005), pH (rho = 0.64, P = 0.006) and right atrial pressure (rho = -0.53, P = 0.011).
  
  
  CONCLUSIONS
  In severe COPD, IPPV increases dPAP and reduces pulmonary pulse pressure during inspiration.
authors.affiliation: Department of Medicine, Monash University, Melbourne, Australia; Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia; Advanced Lung Disease Unit, Royal Perth Hospital, Perth, Australia. Electronic address: jeremy.wrobel@health.wa.gov.au.
authors.forename: Jeremy P
authors.initials: JP
authors.lastname: Wrobel
authors.affiliation: Department of Medicine, Monash University, Melbourne, Australia; Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia.
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Thompson
authors.affiliation: Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Stuart-Andrews
authors.affiliation: Department of Medicine, Monash University, Melbourne, Australia; Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia.
authors.forename: Kirk
authors.initials: K
authors.lastname: Kee
authors.affiliation: Department of Medicine, Monash University, Melbourne, Australia; Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia.
authors.forename: Gregory I
authors.initials: GI
authors.lastname: Snell
authors.affiliation: Department of Anaesthesia, The Alfred, Melbourne, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Buckland
authors.affiliation: Department of Medicine, Monash University, Melbourne, Australia; Allergy, Immunology & Respiratory Medicine, The Alfred, Melbourne, Australia.
authors.forename: Trevor J
authors.initials: TJ
authors.lastname: Williams
mesh_terms: D000368:Aged; D062186:Arterial Pressure / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006801:Humans; D007385:Intermittent Positive-Pressure Ventilation; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D011446:Prospective Studies; D011652:Pulmonary Circulation / Q000502:physiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology* / Q000628:therapy; D013990:Tidal Volume / Q000502:physiology
chemical_list: D010100:Oxygen
keywords: Diastolic pulmonary gradient; Intrathoracic pressure; Pulmonary arterial wedge pressure; Pulmonary hemodynamics; Pulmonary hypertension