Influence of low tidal volumes on gas exchange in acute XXXX and the role of recruitment maneuvers.

@entity1 @entity649 @entity2507
BACKGROUND Use of a low tidal volume (V(T)) strategy in the treatment of acute @entity649 can lead to a decrease in oxygenation. This study evaluated the safety and efficacy of a recruitment maneuver (RM) in this setting. METHODS: Twelve @entity1 with acute @entity649 were studied within 48 hours of diagnosis. Baseline gas exchange, hemodynamics, and respiratory mechanics were determined and @entity1 were placed on a V(T) of 6 mL/kg. Measurements were repeated and an RM of 30 cm H20 for 40 seconds was performed. Measurements were repeated at 30 minutes and 2 hours post-RM. RESULTS: Decreasing V(T) resulted in a decrease in arterial oxygenation (from 91 +/- 9 mm Hg to 75 +/- 9 mm Hg, p < 0.01), an increase in shunt (from 19 +/- 3.7% to 23 +/- 5%, p < 0.01), and a decrease in lung compliance (from 37 mL/cm @entity2507 to 33 mL/cm @entity2507 , < 0.05). At 30 minutes post-RM, oxygenation improved to 99 +/- 16 mm Hg, shunt decreased to 17 +/- 3%, and lung compliance improved to 39 mL/cm @entity2507 (p < 0.05). Two hours later, oxygenation fell (86 +/- 12 mm Hg), shunt increased (20 +/- 3%), and compliance diminished (36 mL/cm @entity2507 ). There were no hemodynamic or barotraumatic complications. CONCLUSION: An RM transiently improves gas exchange during low V(T)ventilation. RMs are well tolerated and no hemodynamic consequences were seen.
