Comparison of the tidal volume of the recruitment maneuver followed by PEEP for mechanically ventilated children
Background Atelectasis occurs in most children during the induction of general anesthesia. In clinical practice, the recruitment maneuver (RM) followed by positive end-expiratory pressure (PEEP) to prevent atelectasis have beneficial effects. It has been shown to improve oxygenation and restore lung volume and may reduce the heterogeneity of the distribution of tidal volume (VT). However, the change in VT due to RM followed by PEEP in pediatric patients during the induction of general
... is unknown. Therefore, we assessed the effects of RM followed by PEEP on VT, respiratory function, and hemodynamics in pediatric patients. Methods Pediatric patients (ASA-PS: 1-2; aged 3 months to 10 years) who underwent general anesthesia for elective dental or oral surgery were divided into three groups: infants (<1 year), preschool children (1-6 years), and school children (6 > years). Following tracheal intubation, mechanical ventilation of the lungs was initiated with controlled ventilation of 15 cmH2O and a PEEP of 4 cmH2O. The RM followed by PEEP was increased progressively in steps of 5 cmH2O every three breaths up to the target level of 35 cmH2O. VT, heart rate (HR), blood pressure (BP), and SpO2 were monitored before and after RM followed by PEEP. The differences in these parameters were analyzed statistically using a paired t-test. Results Sixty patients were included (20 in each group). VT before vs. after RM followed by PEEP were 61.8 ± 9.7 vs 80.1 ± 13.9 mL (p < 0.05) in the infant group, 135.8 ± 28.5 vs 164.0 ± 36.9 mL (p < 0.05) in the preschool children group, 217.7 ± 49.7 vs 246.9 ± 50.1 mL (p < 0.05) in the school children group, respectively. HR and BP before and after RM followed by PEEP increased by 2-3% and decreased by 4-7% in all groups. None of the patients had clinically respiratory (desaturation, barotrauma) or hemodynamic (hypotension) complications. Conclusion RM combined with 4 cmH2O of PEEP resulted in a significant increase in VT (12-18%; 19-29 mL) without respiratory or hemodynamic complications. Therefore, this RM method might improve the lung function in pediatric patients. Trial registration This prospective observational study was conducted after receiving approval from the Ethics Review Board of Kyushu University Hospital (Approval No.30-446).