title: Hemodynamic differences between continual positive and two types of negative pressure ventilation.
abstract: In seven anesthetized dogs, ventilated with matching lung volumes, tidal volumes, and respiratory rates, we compared the effects on cardiac output (CO), arterial venous oxygen saturation difference (SaO2 - SVO2), and femoral and inferior vena cava pressure (1) intermittent positive pressure ventilation with positive end-expiratory pressure (CPPV); (2) iron-lung ventilation with negative end-expiratory pressure (ILV-NEEP); (3) grid and wrap ventilation with NEEP applied to the thorax and upper abdomen (G&W-NEEP). The values of CO and SaO2 - SVO2 with ILV-NEEP were similar to those with CPPV. However, with G&W-NEEP as compared with ILV-NEEP, mean CO was greater (2.9 versus 2.6 L/min, p = 0.02) and mean (SaO2 - SVO2) was lower (26.6% versus 28.3%, p = NS). Mean PFEM-IVC was higher with G&W-NEEP than with the other types of ventilation. We conclude that (1) ILV-NEEP is hemodynamically equivalent to CPPV and (2) G&W-NEEP has less adverse hemodynamic consequences. has less adverse hemodynamic consequences.
authors.affiliation: Critical Care Division, Montreal General Hospital, Quebec, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Lockhat
authors.forename: D
authors.initials: D
authors.lastname: Langleben
authors.forename: A
authors.initials: A
authors.lastname: Zidulka
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D004285:Dogs; D005069:Evaluation Studies as Topic; D005652:Functional Residual Capacity; D006439:Hemodynamics; D008991:Monitoring, Physiologic / Q000379:methods; D011175:Positive-Pressure Respiration / Q000295:instrumentation*; D013990:Tidal Volume; D015919:Ventilators, Negative-Pressure