Measurement of the end-expiratory lung volume without interruption of mechanical ventilation in pediatric patients

Introduction

Monitoring the end-expiratory lung volume (EELV) is a valuable tool to optimize respiratory settings that could be of particular importance in mechanically ventilated pediatric patients. We evaluated the feasibility and precision of an ICU ventilator with an inbuilt nitrogen washout/washin technique in mechanically ventilated pediatric patients.

Methods

Duplicate EELV measurements were performed in 26 patients between 5 and 30 kg after cardiac surgery. All measurements were taken during pressure-controlled ventilation at 0 cmH₂O positive end-expiratory pressure (PEEP).

Results

Linear regression between duplicate measurements was excellent (R² = 0.99). Also, there was good agreement between duplicate measurements, bias -1.0% (-1.7 ml) ± 5.7% (15.5 ml) (Figure 1). The mean EELV was 18.9 ± 4.4 ml/kg at 0 cmH₂O PEEP. The EELV correlated significantly with age (P < 0.001, r = 0.92, R² = 0.79), body weight (P < 0.001, r = 0.90, R² = 0.77) and height (P < 0.001, r = 0.90, R² = 0.79).

Figure 1

abstract

Conclusion

This ICU ventilator with an inbuilt nitrogen washout/washin EELV technique can measure EELV with precision, and can easily be used for mechanically ventilated pediatric patients.