Relationship between ETCO 2 and PaCO 2 under Changing Capnogram in Ventilated Infants with NAVA: An Observational Study.

This observational study evaluated the validity of end-tidal CO ₂ (ETCO ₂ ) as a surrogate for arterial PCO ₂ (PaCO ₂ ) in infants on neurally adjusted ventilatory assist (NAVA), particularly considering the influence of variable spontaneous breathing on capnography waveforms. The study involved 16 infants, analyzing 50 paired ETCO ₂ and PaCO ₂ values. Deming regression analysis highlighted a notably stronger correlation for maximum ETCO ₂ (r ²  = 0.6783, p <0.0001) compared to mean ETCO ₂ (r ²  = 0.5686, p <0.0001) and demonstrated a significantly weaker association for minimum ETCO ₂ (r ²  = 0.1838). These findings emphasize the superior predictive value of maximum ETCO ₂ in estimating PaCO ₂ , advocating its reliable use in clinical monitoring, especially given the dynamic capnography associated with NAVA's variable pressures. The results suggest ETCO ₂ 's potential to enhance noninvasive respiratory management, reduce the frequency of blood sampling, and improve overall care for infants requiring mechanical ventilation.
(© 2023. The Author(s), under exclusive licence to Dr. K C Chaudhuri Foundation.)