Mdi with spacer vs. nebs: how do we know any meds are even getting in? one of my trachees breathes shallow, my 4yo blows into spacer mask- tried model

HHI Vs nebs: I find the use of either method is really kid dependent. The coordination required for proper mdi use with or without a spacer is beyond some kids until school age or later. The brief mdi delivery leaves little margin for error than the longer neb rx. I defer mdi use until the parents are comfortable that the kid is using it correctly with obvious effect.