Hypertonic Saline VS Sodium Chloride

Sodium chloride is saline solution. It comes in a variety of concentrations from .9% (known as normal or isotonic saline) to 10%. Hypertonic simply means it is above the normal concentration foundation in blood and body tissues.
Most commonly prescribed for airway clearance are 7% saline and 3% saline. There is clinical and research evidence that 7% saline can inhibit or even reverse the growth of NTM/MAC.

Sue, I as wondering if you have ever heard that 7% sodium chloride can scar your lungs with long term use. I had a consultation with a cardio-thoracic surgeon who preferred the use of 3%. He mentioned that 7% was useful short term if having an exacerbation. Any thoughts on this. As we all know the 7% is more effective.

I have not heard that. I'm not in a position to do research right now, but will put it on my list to look at.

Hi Sue. Thanks for the response. Unfortunately I don't understand, "Hypertonic simply means it is above the normal concentration foundation in blood and body tissues." Are both elements in our blood and body tissue??

Yes, the regular ("normal") saline concentration in our blood and tissues is usually .9% - of course it can vary slightly among individuals and with some meds and conditions.
When they give you an IV in the hospital, it is most usually .9% saline. They may use it for hydration, add other nutrients, or use it to push IV meds.

Pamela McShane, one of the leading experts in bronchiectasis recommends 7% over 3% in her airway clearance talk. She was at Jewish Health and is at NIH now I think. I think this is correct video.
https://m.youtube.com/watch?v=VEYK67nld_o&t=1058
Hypertonic has been used for a while in cystic fibrosis patients, including pediatric ones, and some older studies are from that group.

I googled (added scholarly in search) "use of hypertonic saline in noncystic fibrosis bronchiectasis. Here is a 2019 review of studies, but there are more if you want to check. This article does mention that a few patients couldn't participate due to poor tolerance of the 7% and perhaps your doc was thinking of those.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6688147/
The goal is to get the mucus out and if 3% helps you do that and you tolerate it, I'd say it's achieving the goal. If you aren't getting it out and are having exacerbations, you might consider altering your airway clearance routine, the saline being just one option. Good luck! It's all these details...

I forgot to explain why the hypertonic helps.
Saline in just salt (sodium chloride) water. As Sue said, the .9 is the same concentration as in our body (isotonic). The higher amounts of salt draw more water from body into airways, thinning the mucus and making it easier to cough out.

I have heard on this group of studies which also point out that 7% saline is more effective at keeping MAC away than the 3% saline. I could be misremembering.

You are remembering correctly! There have been a number of studies published. This may be the most readable one:
https://pmc.ncbi.nlm.nih.gov/articles/PMC4850692/pdf/13104_2016_Article_2054.pdf
Along with airway clearance, I truly believe it has helped keep my lungs clear of infections.

pacathy. Thanks for the detailed description of the way saline, via nebbing, effects the airways. I've never heard it explained like that.
Faye