Agreement Between Automated and Equation-Derived Mechanical Power in Pediatric Mechanical Ventilation

Newer ventilators provide automated real-time mechanical power (MP_auto) measurements, but their accuracy in children across ventilation modes remains uncertain. We aimed to evaluate the agreement between the MP_auto measured on the Mindray SV-600 ventilator and the equation-derived MP (MP_calc) across two tidal volume (V_T) settings, ventilation modes, and predefined age groups in ventilated children.

In this prospective observational physiology study, consecutive mechanically ventilated children aged 1 month to 18 years were enrolled between August 2024 and May 2025 in a 30-bed pediatric ICU. MP_auto was compared with MP_calc, using comprehensive and surrogate equations during continuous mandatory volume-control (VC-CMV) and pressure-control (PC-CMV) modes at V_T of 6 and 8 mL/kg body weight. Subgroup analyses considered age and pediatric ARDS. In VC-CMV mode, MP was calculated with Gattinoni's equation (MPVC_{comprehensive}) and Giosa's equation (MPVC_surrogate). In PC-CMV mode, Van der Meijden's equation (MPPC_{comprehensive}) and Becher's equation (MPPC_surrogate) were used. Bland-Altman analyses evaluated agreement.

We included 147 children, with a median (interquartile range [IQR]) age of 49 (16-92) months, of whom 34 (23%) had pediatric ARDS. MP_auto showed strong agreement with MP_calc across ventilation modes and V_T settings. The agreement was highest in VC-CMV, with minimal bias (-0.12 to +0.011 J/min; intra-class correlation [ICC] ≥0.95) and >88% of observations within clinical limits of agreement. In PC-CMV, MP_auto demonstrated a systematic negative bias relative to MP_calc (minimal bias -1.23 to -0.62 J/min; ICC ≥0.92), with similar findings in subjects with pediatric ARDS. Age influenced agreement between MP_auto and MP_calc (slope -0.008 to -0.005), especially in PC-CMV mode (R² = 0.226-0.27). Pediatric ARDS status affected this relationship only in PC-CMV mode (P = .02 for MPPC_{comprehensive} and P = .006 for MPPC_surrogate).

MP_auto demonstrated strong agreement with equation-derived MP during VC-CMV mode across different age groups. However, MP_auto showed a systematic negative bias relative to equation-derived MP in PC-CMV mode, particularly among younger children and those with pediatric ARDS.