What backpack do you use to fly/ that can count as a medical device?

Going to be traveling this summer with my husband and 6.5 month old and looking to buy a backpack that fits my Spectra and Eufy wearable. Not sure if I should use a cooler or portable breastmilk cooler like Ceres chill? Thoughts on bringing frozen milk? Also, can I put her diapers and wipes in the bag too or will they say it’s no longer a medical device bag? Any recs or advice would be super helpful! (We’re flying delta and have a plane change. First flight 2 hrs. The second is about 45 minutes- very small plane. Then we have a 45 minute drive to get to our destination.)