Measuring your PEF is important, because it lets you:
I'm wondering if this doctor has seen you enough in distress, having asthma attacks to really know what your personal best is. I'm not a medical professional by any means, but if you are feeling that bad and you think 370 is supposed to your personal best, maybe you have been misinformed.
If your peak flows are at 370 and you are still have so much trouble, I have to wonder if that really is your personal best peak flow. I think the air purifier is a great idea. I have one in my bedroom and it really helps.
As for your question about what kind of environment is better to live in, I really don't know. I have a friend here who is trying to sell her home so she can move to Florida because she says she can breathe so much better there.
I really wish you would ask your doctor about the Xopenex inhaler. It has made such a difference for me. None of the other inhalers really did anything for me. I would have to use my nebulizer with the Xopenex in it.
When I think I'm in trouble, the peak flow tells me a lot. If I call my allergist's office and say I'm in trouble, can I come in, the first thing they do is take my peak flows and the doctor listens to my chest. Usually when I've made those calls, I am in trouble and they have to give me epinephrine, sometimes several injections. Taking epi is no fun at all if you have never had it. It makes you want to climb the walls, but it opens up your lungs.
In answer to your question about the medication helping my reflux, yes, Nexium definitely does the job. The others I have tried did not. If the Prilosec doesn't help you, I would go straight for the Nexium.
I know you are really frustrated and I totally understand, I am here for you if I can help you in any way. I know it must be extra tough going through this and taking care of kids also.