Air vent/filters for IV infusions

offlabel · Dec 30, 2022

This is a really good discussion to have because there is so much misunderstanding and confusion as to the whys of air filters.

That said, IMHO the issues are a little different in peds/neonates than in adults, that's because there are more unrepaired atrial and ventricular septal defects in the former group than the latter. The thing to really find out about a patient on whom you're thinking about an air filter for is what direction the blood is flowing through the septal defect. In adults that have PFO's, they're usually incidentally discovered, are pretty small and are left to right, thus posing no danger of air bubble mediated stroke. Patients like this may have had many IV's in the past without air traps or any problems at all. If any air were to get in, it would travel to the lungs, get trapped and then absorbed just like it does for anyone else.

The problem would come when there was a right to left movement of blood and the potential for bubbles entering the left atrium to left ventricle to arterial/carotid circulation would be higher.

The practical problem with air traps is that there are a fluids and drugs that just won't get through them and they need to be bypassed. Also, they restrict brisk flow so if you need to give volume or blood quickly, if you don't have an air venting valve, just being really careful, especially in the peds/neonate population is what's called for when faced with that situation.

More to say, but I'll stop there and see what folks have to add.