The triggering factors could range from simple dust to certain strong or irritating scents or perfumes. Whatever the triggering factor(s) may be, it must be determined right away so that the process in diagnosing asthma can proceed to the next level, which is the physical examination.
In the physical examination, the doctor will usually begin by checking the upper respiratory tract of the patient. The chest and skin will also be assessed following the medical history. The doctor may also need to look at the patient's nose for signs of excessive nasal secretions, nasal polyps or inflamed nasal linings.
The doctor will also listen to the lungs. If the doctor can hear wheezing sounds it may be another sign that the patient has asthma.
The last part of the physical examination the doctor checks the skin of the patient for hives or eczema, because there are cases when asthma is greatly associated with certain skin conditions.
The next step in diagnosing asthma is by letting the patient undergo lung function tests. Listening to the sounds of the lungs through a stethoscope is clearly not sufficient to diagnose whether a patient has asthma or not. It is just like a "sneak preview" of the condition of the lungs while the lung function test is the "full-length movie" which offers more details and information about the condition of the lungs.
Spirometry is considered to be the most basic lung function test. This is a non-invasive test that measures how well a person can breathe. When a patient undergoes spirometry, the patient has to take deep breaths and then exhales those breaths forcefully into a hose connected to a spirometer (the machine used for spirometry).