We use mainstream ETC02 on all NICU vent patients, excluding HFV. Compared to adults, generally there is a larger gap between PAC02 and ETC02 for many reasons. The one I am interested in is the possible inability for the neonate to completely exhale due to their rapid respiratory rate. The typical or "best" waveform is rarely seen and when it is, the values tend to be quite higher than the average. Does anyone have an opinion on this therory or possibly use a manuver to achieve a best or most accurate value?