There is a simple, pocket-sized device called a peak flow meter that can detect narrowing in your airways hours, or even days, before you feel symptoms. You simply blow into it, as instructed in your doctor’s office, to monitor your airways the same way you might use a blood pressure cuff to measure high blood pressure or a thermometer to take your temperature. Peak flow meters come in many shapes and styles. Ask your doctor which is right for you. Your doctor may divide your peak flow numbers into zones ( green = safe ; yellow = caution ; red = emergency ) and develop a plan with you. Your peak flow number will help you know:
Airway remodeling is when there are permanent physical changes to the airways that also affects how they work. This may happen after chronic long-term asthma. After cycles of inflammation, damage and repair to the airways. permanent remodeling of the airways may occur. This is when the physical structure of the airway changes. This will cause permanent airway narrowing (they are always more narrow than normal and get narrower during an asthma attack), bronchospasms are more easily triggered (bronchial hyperresponsivenes), airway edema (fluid in the airway), and mucus hypersecretion (too much mucous is made) as well as the build-up of collagen around the airway which is called fibrosis. Airway remodeling has been observed in chldren as young as six. 
Dr. Mike, I’d be very grateful if you helped me, for I’m at a loss! I live in Spain where I have no private medical insurance, just Social Security, where doctors are overworked and uninterested. I have persistent asthma and was given Symbicort and Singulair, but we just found out I’m allergic to corticosteroids (hives, edema, paradoxycal bronchospasm). Singulair helps greatly but only lasts 3 hours. Inhaled powders and aerolizers tend to irritate my airways and often cause paradoxical bronchospasm and make me worse (about 50% of the time). My last resorts are theophylline and clembuterol or other oral bronchodilators. I am currently self-medicating using ephedrine until my next appointment (after powdered formoterol’s total failure). Ephedrine is working fairly well, but I’m developing rapid tolerance. My questions are: can these oral b2 agonists such as clembuterol, salbutamol tablets or terbutaline tablets be used as a long-term option without developing tolerance? Does the xantine theophylline develop tolerance just like caffeine? In sum, can severe asthma be managed without the use of corticosteroids? Iprathropium bromide is unlikely to work because I don’t react to methacoline. I just want to know if whatever they give me will simply help me temporarily until I end up dying shortly of breathing inssufficiency or a heart attack. I’m permanently panting lightly despite the ephedrine (150 mg/day, currently), with serious exacerbations during the day upon minimal exertion, such as washing the dishes, that require an hour in bed to return to my regular light-panting pattern. I could erradicate the panting completely by adding more and more ephedrine, or nebulizing with huge doses of ventolin, but I’m not doing it right now for obvious reasons. I’m a 32 y/o athletic male.