Dependency of respiratory system mechanics on positive end-expiratory pressure and recruitment maneuvers in lung healthy pediatric patients-A randomized crossover study

Background The lungs of pediatric patients are subjected to tidal derecruitment during mechanical ventilation and in contrast to adult patients this unfavorable condition cannot be resolved with small c increases. This raises the question if higher end-expiratory pressure increases or recruitment maneuvers may resolve tidal derecruitment in pediatric patients. Aims We hypothesized that higher PEEP resolves tidal derecruitment in pediatric patients and that recruitment maneuvers between the pressure changes support the improvement of respiratory system mechanics. Methods The effects of end-expiratory pressure changes from 3 to 7 cmH(2)O and vice versa without and with intermediate recruitment maneuvers on respiratory system mechanics and regional ventilation were investigated in 57 mechanically ventilated pediatric patients. The intratidal respiratory system compliance was determined from volume and pressure data before and after PEEP changes and categorized to indicate tidal derecruitment. Results Tidal derecruitment occurred comparably frequently at PEEP 3 cmH(2)O without (13 out of 14 cases) and with recruitment maneuver (14 out of 14 cases) and at PEEP 7 cmH(2)O without (13 out of 14 cases) and with recruitment maneuver (13 out of 15 cases). Conclusions We conclude that contrary to our hypothesis, PEEP up to 7 cmH(2)O is not sufficient to resolve tidal derecruitment and that recruitment maneuvers may be dispensable in mechanically ventilated pediatric patients.