Do you think you could find an allergist who would take them on. It is a known fact that asthma patients treated by allergist do better. Here is a good web site for you about
peak flow meters and other information: http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E&b=22586#whatis
an allergist would give you one or you can buy one for about
In my opinion, and I am not a medical professional, just a person who has had a lot of asthma attacks and had to learn how to deal with them, I think your 8 year old could start out by measuring his peak flows when he's doing well, maybe in the morning and possibly at night so that your would know what his norm is. Then when he has some wheezing, but not exactly an asthma attack, see what those numbers are, which they should be lower. Then when you have to use the nebulizer, use the peak flow first and see what the numbers are, don't keep repeating it though, because it can use up his air. But it can let you know when you are in real trouble. They call it the green, yellow and red zone. Red zone is when you call 911. Keep a record of all of these with the dates and times, you might be able to pin point something that is triggering his attacks, doubtful, but worth a try.
You really need to talk to your doctor about this, but I strongly encourage you to try to find an allergist to treat the boys. Please let me know if there is anything I can do to help you.