OBJECTIVE: The aim of this study was to evaluate the effects of respiratory rate (RR) at a constant PaCO2 and conventional tidal volume (VT) on the development of ventilator-induced lung injury in normal lungs. DESIGN: Prospective, randomized, experimental study. SETTING: University research laboratory. SUBJECTS: Adult male C57BL/6 mice. INTERVENTIONS: Four groups of anesthetized mice were exposed to mechanical ventilation with different RRs and VTs. Three groups were assigned to one of three RRs (80, 120, and 160 breaths/min), and VT was set to 12, 10, and 8 mL/kg, respectively (RR80 VT12, RR120 VT10, and RR160 VT8), to achieve normal PaCO2. A fourth group was ventilated at 160 breaths/min and VT of 10 mL/kg (RR160 VT10) with adjustment of dead space. All animals were ventilated for 120 mins with a positive end-expiratory pressure of 1.5 cm H2O and FiO2 of 1. Nonventilated animals were also studied. MEASUREMENTS AND MAIN RESULTS: Arterial blood gases and static pressure-volume curves were not different among groups at the end of the experiment. Independent of ventilator settings, mechanical ventilation was associated with increased bronchoalveolar lavage protein and increased bronchoalveolar lavage and serum interleukin-6. Total bronchoalveolar lavage protein and interleukin-6 were significantly lower in RR80 VT12 and RR160 VT8 compared with RR120 VT10 and RR160 VT10. In all experimental conditions, mechanical ventilation was associated with activation of AKT and ERK1/2 kinases, known to be activated on stretch. Phosphorylation both of AKT and ERK1/2 was lower in RR80 VT12 compared with other groups of ventilated animals. Histologic injury did not differ among nonventilated, RR80 VT12, and RR160 VT8 animals; however, it increased significantly and progressively in RR120 VT10 and RR160 VT10 animals. CONCLUSIONS: Mechanical ventilation with conventional VT induces lung injury in normal lungs, even without alteration in lung mechanics. Reduction of RR and VT ameliorates lung inflammation and injury.
OBJECTIVE: The aim of this study was to evaluate the effects of respiratory rate (RR) at a constant PaCO2 and conventional tidal volume (VT) on the development of ventilator-induced lung injury in normal lungs. DESIGN: Prospective, randomized, experimental study. SETTING: University research laboratory. SUBJECTS: Adult male C57BL/6 mice. INTERVENTIONS: Four groups of anesthetized mice were exposed to mechanical ventilation with different RRs and VTs. Three groups were assigned to one of three RRs (80, 120, and 160 breaths/min), and VT was set to 12, 10, and 8 mL/kg, respectively (RR80 VT12, RR120 VT10, and RR160 VT8), to achieve normal PaCO2. A fourth group was ventilated at 160 breaths/min and VT of 10 mL/kg (RR160 VT10) with adjustment of dead space. All animals were ventilated for 120 mins with a positive end-expiratory pressure of 1.5 cm H2O and FiO2 of 1. Nonventilated animals were also studied. MEASUREMENTS AND MAIN RESULTS: Arterial blood gases and static pressure-volume curves were not different among groups at the end of the experiment. Independent of ventilator settings, mechanical ventilation was associated with increased bronchoalveolar lavage protein and increased bronchoalveolar lavage and serum interleukin-6. Total bronchoalveolar lavage protein and interleukin-6 were significantly lower in RR80 VT12 and RR160 VT8 compared with RR120 VT10 and RR160 VT10. In all experimental conditions, mechanical ventilation was associated with activation of AKT and ERK1/2 kinases, known to be activated on stretch. Phosphorylation both of AKT and ERK1/2 was lower in RR80 VT12 compared with other groups of ventilated animals. Histologic injury did not differ among nonventilated, RR80 VT12, and RR160 VT8 animals; however, it increased significantly and progressively in RR120 VT10 and RR160 VT10 animals. CONCLUSIONS: Mechanical ventilation with conventional VT induces lung injury in normal lungs, even without alteration in lung mechanics. Reduction of RR and VT ameliorates lung inflammation and injury.
Authors: Paula W Steimback; Gisele P Oliveira; Andréia F Rzezinski; Pedro L Silva; Cristiane S N B Garcia; Graziela Rangel; Marcelo M Morales; José R Lapa E Silva; Vera L Capelozzi; Paolo Pelosi; Patricia R M Rocco Journal: Intensive Care Med Date: 2009-02-17 Impact factor: 17.440
Authors: Tommaso Tonetti; Francesco Vasques; Francesca Rapetti; Giorgia Maiolo; Francesca Collino; Federica Romitti; Luigi Camporota; Massimo Cressoni; Paolo Cadringher; Michael Quintel; Luciano Gattinoni Journal: Ann Transl Med Date: 2017-07
Authors: John G Laffey; Giacomo Bellani; Tài Pham; Eddy Fan; Fabiana Madotto; Ednan K Bajwa; Laurent Brochard; Kevin Clarkson; Andres Esteban; Luciano Gattinoni; Frank van Haren; Leo M Heunks; Kiyoyasu Kurahashi; Jon Henrik Laake; Anders Larsson; Daniel F McAuley; Lia McNamee; Nicolas Nin; Haibo Qiu; Marco Ranieri; Gordon D Rubenfeld; B Taylor Thompson; Hermann Wrigge; Arthur S Slutsky; Antonio Pesenti Journal: Intensive Care Med Date: 2016-10-18 Impact factor: 17.440
Authors: Holger C Müller; Katharina Hellwig; Simone Rosseau; Thomas Tschernig; Andreas Schmiedl; Birgitt Gutbier; Bernd Schmeck; Stefan Hippenstiel; Harm Peters; Lars Morawietz; Norbert Suttorp; Martin Witzenrath Journal: Crit Care Date: 2010-07-30 Impact factor: 9.097