Hi Amy,
Yep, I've started to dispense the saline directly using the measures on the side of the ampoules. I mix approximately 1.7 ml of 3% with 2.3 ml of 10%, which yields 4 ml of 7%, eliminating the need to get rid of the extra ml you get when you mix 2 ml of 3% with 3 ml of 10%. I've checked the volumes I get by eyeballing and they're pretty close to what I get with the syringe.
I've also recently found out that Dey, the company that provides the saline to the CF Pharmacy, makes 3-ml ampoules of 9% saline. One of those mixed with 1 ml of normal (0.9%) saline would also yield a 7% solution, with considerably less fuss and waste than we've got now. I'm trying to reach the medical director at the CF Foundation to see about switching to this option.
Bambi, mom of Jordan, 17 w cf