MEASUREMENT OF RESPIRATORY MECHANICS IN PEDIATRIC INTENSIVE-CARE - IN-VITRO ASSESSMENT OF A PULMONARY-FUNCTION DEVICE

Objective: To evaluate a recently developed and manufactured device fo r monitoring respiratory parameters in mechanically ventilated childre n. Design: In vitro study using a lung model. Setting: University paed iatric intensive care unit. Material and interventions: Evaluation of the accuracy of volume and pressure measurements, of the determination of respiratory system compliance (10 to 30 ml/cmH(2)O) and of resista nce (20 and 50 cmH(2)O/l per s) by the inflation technique (volume- an d pressure-controled mode of ventilation); assessment of interobserver agreement for compliance (10, 15 ml/cmH(2)O) and resistance (20, 50 c mH(2)O/l per s) determinations (ANOVA, intraclass correlation coeffici ent). Measurements and results: The accuracy of volume measurements (N o. 1 Fleisch pneumotachograph) was less than or equal to 5 % of true v olumes up to 1 l (Flow: 30 l/min) even after the introduction of an en dotracheal tube. The accuracy of pressure measurements up to 70 cmH(2) O was 12.5 % of the true values. Coefficients of variation of volume a nd pressure measurements were < 2%. The accuracy of compliance and res istance determinations was, respectively, less than or equal to 17 and 25 % of the true values. No significant observer effect was found on compliance and resistance determinations. Indeed, mean differences in compliance and resistance determinations by pairs of observers were < 1%. Intraclass correlation coefficients were > 0.98. Conclusions: The measuring error of volume, pressure, compliance and resistance determi ned using this monitoring system seems acceptable for monitoring purpo se. Moreover, use of this system by members of the medical team can be recommended since results obtained by observers, even untrained ones, were similar. In vivo evaluation is now needed.