Background: Lung recruitment maneuvers are frequently used in the treatment of children with lung injury. Here we describe a pilot study to compare the acute effects of 2 commonly used lung recruitment maneuvers on lung volume, gas exchange, and hemodynamic profiles in children with acute lung injury.
Methods: In a prospective, non-randomized, crossover pilot study, 10 intubated pediatric subjects with lung injury sequentially underwent: a period of observation; a sustained inflation (SI) maneuver of 40 cm H2O for 40 seconds and open-lung ventilation; a staircase recruitment strategy (SRS) (which utilized 5 cm H2O increments in airway pressure, from a starting plateau pressure of 30 cm H2O and PEEP of 15 cm H2O); a downwards PEEP titration; and a 1 hour period of observation with PEEP set 2 cm H2O above closing PEEP.
Results: Arterial blood gases, lung mechanics, hemodynamics, and functional residual capacity were recorded following each step of the study and following each increment of the SRS. Both SI and SRS were effective in raising PaO2 and functional residual capacity. During the SRS maneuver we noted significant increases in dead-space ventilation, a decrease in carbon dioxide elimination, an increase in PaCO2, and a decrease in compliance of the respiratory system. Lung recruitment was not sustained following the decremental PEEP titration.
Conclusions: SRS is effective in opening the lung in children with early acute lung injury, and is hemodynamically well tolerated. However, attention must be paid to PaCO2 during the SRS. Even minutes following lung recruitment, lungs may derecruit when PEEP is lowered beyond the closing pressure.
Keywords: ARDS; acute lung injury; functional residual capacity; recruitment maneuver; staircase recruitment strategy.