Asthma diagnosis

If you have or have had episodes of wheezing and wheezing in the past, especially when you exhale deeply, as well as episodes of shortness of breath (shortness of breath), lack of air and heaviness in the chest, coughing attacks that begin more often at night and / or early in the morning, then inform about them to your doctor. Tell us about them if, at the time of the visit to the doctor, these symptoms have already passed. To diagnose asthma, your doctor must thoroughly review your health information. The doctor should also clarify what diseases you have suffered and whether you have an allergy. If, on the basis of the medical history, the diagnosis of asthma is still questionable, additional examinations are necessary.
There is no one and only way to diagnose asthma, and it cannot be diagnosed only on the basis of a questionnaire. Usually, the doctor begins by listening to the lungs with a stethoscope, which helps to determine if there is inflammation in the airways. In case of asthma, whistles, wheezing and / or prolonged exhalations are heard when listening in the lungs. If the above symptoms are not found during listening, then this does not mean that the diagnosis of asthma is excluded. If your doctor suspects you have asthma, he may order a spirographic examination. If the spirographic examination did not show signs of asthma, but you still have asthma symptoms that occur day or night for an unknown reason, then you will be prescribed trial treatment or referred to a pulmonologist for a consultation.



Spirography is an examination of the airways, during which the volume and speed of movement of the inhaled and exhaled air, as well as the occupancy of the pulmonary tract, are evaluated. Thus, we are dealing with the study of pulmonary function. Spirography is painless and does not cause any significant harm to your well-being. In some cases, frequent strong inhalation / exhalation can increase pressure in the chest, abdomen and intraocular pressure and thus cause discomfort. There are contraindications for spirography, which you or your doctor or nurse will inform you before the examination. The doctor and nurse will give you exact instructions for what you need to monitor before coming to the examination:

  • If you use an adjuvant with bronchodilating substances (bronchodilators), or the so-called inhaler, then depending on the duration of the medicine, the doctor will give you a recommendation not to use it from 4 to 24 hours before the examination.
  • Avoid Exercise
  • Do not smoke
  • Do not come to the examination with a full stomach, but two hours before the examination you can have a little snack.

Spirographic examination

  1. Before the examination you will be weighed and measured, the data will be entered into a computer
  2. During the examination, your nose will be covered with a clothespin to exclude breathing through the nose and a special mouthpiece will be placed in your mouth. The mouthpiece is held in the mouth and you will breathe through it throughout the examination, the back and neck should be straight .
  3. First, the doctor or nurse will ask you to inhale and exhale several times through the mouthpiece at a calm pace.
  4. Next, you will need to inhale as deep as possible and then exhale as quickly as you can, until the lungs are completely clean. This may take a few seconds. The nurse will tell you how long you will have to breathe at that pace.    
  5. You may be asked to inhale as deeply as possible and then exhale as long as possible until the lungs are clear.   
  6. Such breathing cycles are usually carried out several times – at least three times, but usually no more than eight times. If lung function is impaired, then you will need to take fast-acting bronchodilators and after 15 minutes a new spirographic examination will be performed. 

What do spirography results show?

Spirography measures the volume and / or speed of air movement that a person can inhale and exhale. Most commonly measured:

  1. The amount of air that you can exhale with force for one second after a maximum breath. This is called forced expiratory volume in 1 second (FEV ). If the airways are in order, a person can breathe out most of the air in the lungs within one second.      
  2. The maximum volume of air that you can exhale with force after maximum inhalation. This volume is called the forced vital capacity of the lungs (FVC).

As a result of calculating the results of spirography, the above two indicators are compared with the control indicators. Your age, height and gender affect lung volume and are taken into account when calculating the results. Asthma can be indicated by the fact that the FEV / FVC ratio is less than the control value. Low values ‚Äč‚Äčindicate that your airways have narrowed, which is a typical sign of asthma. Usually, spirography is repeated again after you take a breath-relaxing medicine. If you have asthma, then during the examination conducted after taking the medicine, the maximum expired air volume will be increased. If a spirographic examination does not give results that would clearly indicate asthma, then the doctor may prescribe you a trial treatment with inhaled glucocorticoids. The doctor will evaluate the effect of the trial after four weeks: asthma will be indicated by an increase in FEV 1 of at least 200 ml or a significant improvement in clinical symptoms. It may happen that spirography is contraindicated for you. In this case, for exceptional diagnostic purposes, PEF-metry or measurement of the peak velocity of expiratory (expired) air is used against the background of trial treatment. Peak expiratory flow rate is measured using three consecutive measurements using a PEF meter, the highest value of which is taken (Quanjer et al 1997). During the measurement, the patient can stand or sit and his back and neck should be straight (McCoy et al 2010). Using the PEF meter, the maximum exhaled air speed is determined .  

If your complaints and clinical symptoms make it possible for the doctor to suspect you have asthma, but the results of spirography and trial treatment do not confirm the diagnosis, then the doctor will refer you to a pulmonologist. If your cough lasts longer than eight weeks, then you may get an x-ray, although in general it is not done to diagnose asthma . For diagnosis, you do not need to determine allergens . If the doctor still suspects that your asthma symptoms are caused by an allergy, that is, allergic asthma occurs, then you need to do skin tests or a blood sample to clarify possible allergens.     


Important to remember:Diagnosis of asthma is based on symptoms and results of examination and treatment.     Tell your doctor about the manifestations of respiratory failure in different situations, as well as your options for the causes that may cause them.Symptoms inherent in asthma:wheezing and wheezing in the chest, especially when exhaling deeplyoccasional breathing difficultieslack of air and a feeling of heaviness in the chestcoughing attacks that occur more often at night and / or early in the morningIf asthma is suspected, a spirographic examination is performed, if necessary, together with a test for bronchodilatorsIf it is impossible to diagnose asthma on the basis of a spirogram, but asthma remains suspicious on the basis of clinical symptoms, your doctor may prescribe you a trial treatment with basic inhaled asthma medications or refer you to a pulmonologist.For each patient, the doctor decides separately whether he needs additional examinations. Each patient does not need them.
event_note April 12, 2020

account_box Kroll

Leave a Reply

Your email address will not be published. Required fields are marked *