Manipulating positive end expiratory pressure to recruit lung volume in mechanically ventilated children

Background - Mechanically ventilated children are at risk of chronic de-recruitment with low tidal volume ventilation and acute de-recruitment with each disconnection from the circuit and application of suction. Lung recruitment manoeuvres have demonstrated gain in end expiratory levels (EEL) in both adult and experimental studies. Aim - To quantify the impact of two different methods of manipulating PEEP on EEL and regional gas distribution as measured by electrical impedance tomography (EIT) . Method - A randomised crossover clinical trial in 60 intubated and mechanically ventilated children in a PICU. Forty children underwent two methods of lung recruitment following endotracheal suctioning: a double baseline PEEP manoeuvre – held for two minutes and an incremental PEEP manoeuvre, each step held for one minute. Twenty children acted as controls. EIT measurements to quantify EEL were taken at baseline and at 15 minute intervals throughout the study period. Results - The Double PEEP manoeuvre showed significant and sustained improvement in global EEL from baseline up to 120 min (P < 0.01 ANOVA). Global EEL did not change with the Incremental PEEP manoeuvre or in the control group. The Double PEEP manoeuvre also demonstrated preferential ventilation distribution towards the dependent regions of the lung (P = 0.03 ANOVA). Nil adverse events were observed. Conclusion - Significant increases in EEL were achieved globally with a simple Double PEEP manoeuvre. The magnitude of the dependent ventilation also increased, suggesting genuine alveolar recruitment in dependent regions of the lung that was sustained for up to 120 min.