title: Venous gas embolism: time course of residual pulmonary intravascular bubbles.
abstract: The time course of pulmonary intravascular air emboli was studied in anesthetized dogs. In one series of experiments air was infused into the right atrium at 0.10 ml.kg-1.min-1 or 0.25 ml.kg-1.min-1 for 15 min or given as a bolus injection of 2 ml/kg at 2 ml/sec. In a second series of series of experiments venous air was infused into dogs (0.25 ml.kg-1.min-1, 15 min) ventilated with 100% oxygen for 0, 30, or 210 min before the embolization. After the air infusions the animals were allowed to recover, breathing 70% nitrogen:30% oxygen. At 10-min intervals during recovery, the nitrogen was replaced with nitrous oxide (N2O) for 5 min to expand any residual pulmonary vascular bubbles. Subsequent changes in pulmonary artery pressure (Ppa) and end-tidal carbon dioxide (PETCO2) concentrations, pulmonary vascular resistance (PVR) and carbon dioxide tensions (PaCO2) as a result of the N2O challenges indicated the presence of residual gas bubbles in the pulmonary arterial system. Residual times of the pulmonary bubbles were 24.5 +/- 12.3 min (0.10 ml.kg-1.min-1 air dose), 43 +/- 10.8 min (0.25 ml.kg-1.min-1 air dose), and 17.8 +/- 2.5 min (bolus). The latter two were significantly different from each other. With 100% oxygen breathing the residual times were 19 +/- 2.2 (0 min), 22 +/- 6.7 min (30 min), and 17 +/- 4.0 (210 min). These values were reduced significantly when compared to the dogs ventilated with 30% oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Anesthesiology, University of Texas Medical School, Houston.
authors.forename: B D
authors.initials: BD
authors.lastname: Butler
authors.forename: S
authors.initials: S
authors.lastname: Luehr
authors.forename: J
authors.initials: J
authors.lastname: Katz
mesh_terms: D000818:Animals; D001794:Blood Pressure; D003665:Decompression Sickness / Q000097:blood / Q000503:physiopathology / Q000628:therapy; D004285:Dogs; D004618:Embolism, Air / Q000097:blood / Q000503:physiopathology* / Q000628:therapy; D005740:Gases / Q000097:blood; D007700:Kinetics; D010100:Oxygen / Q000008:administration & dosage; D011652:Pulmonary Circulation; D014655:Vascular Resistance
chemical_list: D005740:Gases; D010100:Oxygen