title: Inhaled prostacyclin (PGI2) versus inhaled nitric oxide in adult respiratory distress syndrome.
abstract: Inhalation of nitric oxide (NO) and prostacyclin (PGI2) may induce selective pulmonary vasodilation and-by improving ventilation-perfusion ratio in ventilated areas of the lung-increase Pao2 in patients with acute lung injury. To assess the therapeutic efficacy of both compounds, dose-response curves were established in patients with adult respiratory distress syndrome (ARDS). Patients received both PGI2 (doses of 1, 10, and 25 ng/kg/min) and NO (concentrations of 1, 4, and 8 ppm). Cardiorespiratory parameters were assessed at control, at each drug concentration, and after withdrawal of NO and PGI2. PGI2 resulted in a significant, dose-dependent and selective reduction of pulmonary artery pressure (PAP) from 35.1 +/- 6.3 mm Hg at control to 33.1 +/- 4.8 (1 ng/kg/min), 31.3 +/- 4.8 mm Hg (10 ng/kg/min) and 29.6 +/- 4.5 mm Hg (25 ng/kg/min), respectively. Inhaled NO reduced PAP from 34.5 +/- 5.6 to 32.1 +/- 5.9 mm Hg at 4 ppm, and to 31.8 +/- 6.1 mm Hg at 8 ppm, respectively, with no effect at 1 ppm. Pao2/Flo2 ratio increased from 105 +/- 37 to 125 +/- 56 mm Hg (range of increase: 0 to 57 mm Hg) at PGI2 10 ng/kg/min and to 131 +/- 63 mm Hg (range: -5 to 89 mm Hg) at 25 ng/kg/min with no effect at 1 ng/kg/min. NO improved Pao2 (e.g., from 116 +/- 47 to 167 +/- 86 mm Hg at 8 ppm) and reduced intrapulmonary shunt at all doses tested. We conclude that both inhaled PGI2 and NO may induce selective pulmonary vasodilation and increase Pao2 in severe ARDS.
authors.affiliation: Department of Anesthesiology, Ludwig-Maximilians-Universität München, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Zwissler
authors.forename: G
authors.initials: G
authors.lastname: Kemming
authors.forename: O
authors.initials: O
authors.lastname: Habler
authors.forename: M
authors.initials: M
authors.lastname: Kleen
authors.forename: M
authors.initials: M
authors.lastname: Merkel
authors.forename: M
authors.initials: M
authors.lastname: Haller
authors.forename: J
authors.initials: J
authors.lastname: Briegel
authors.forename: M
authors.initials: M
authors.lastname: Welte
authors.forename: K
authors.initials: K
authors.lastname: Peter
mesh_terms: D018806:APACHE; D000280:Administration, Inhalation; D000328:Adult; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000008:administration & dosage*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000008:administration & dosage*; D011652:Pulmonary Circulation / Q000187:drug effects; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D012128:Respiratory Distress Syndrome / Q000188:drug therapy* / Q000503:physiopathology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D014665:Vasodilator Agents; D009569:Nitric Oxide; D011464:Epoprostenol