Inspiratory temporal patterning and mechanical architecture shape regional energy distribution in a multicompartment lung model

Abstract Mechanical power summarizes the global energetic load of mechanical ventilation, but heterogeneous lungs may route the same load differently across regional pathways. We used a simplified six-compartment model to test whether global inspiratory mechanical power uniquely determines regional inspiratory energy distribution. Compliance-dominant, resistance-dominant, and mixed resistance–compliance architectures were simulated at fixed tidal volume, respiratory rate, and PEEP while inspiratory waveform, inspiratory time, and end-inspiratory pause were varied. Regional energy allocation depended strongly on mechanical architecture. Longer inspiration increased energy inequality in the compliance-dominant phenotype, reduced it in the resistance-dominant phenotype, and produced a smaller decrease in the prespecified inversely paired mixed configuration. Exhaustive permutation of resistance–compliance pairings showed that the mixed response depended on compartment-level organization and time-constant dispersion rather than representing a universal mixed-heterogeneity behavior. Waveform shape also altered normalized regional energy allocation. Simulations with similar global mechanical power nevertheless showed substantial differences in regional energy concentration and dominant compartment energy share. Global mechanical power therefore did not uniquely describe pathway-level energetic exposure in this heterogeneous model. Inspiratory timing should be interpreted in relation to the underlying organization of regional resistance and compliance.