EVH test (hyperventilation test): preparation and procedure.

What the test shows.

In the EVH test you breathe quickly and deeply for six minutes from a dry air mixture, so the airways are exposed to the same conditions as during hard training. It is used especially with breathlessness during sport.

How to prepare.

• Important information about your medication: only pause if the clinic has asked you to. If the clinic has given you instructions, follow them, and call if you are in doubt.
• Medication pause (the clinic's standard): short-acting reliever (e.g. salbutamol): 8 hours · long-acting beta2 agonist (e.g. formoterol, salmeterol): 36–48 hours · ultra-long-acting beta2 agonist (e.g. vilanterol, indacaterol): 48 hours · ipratropium (e.g. Atrovent): 12 hours · long-acting anticholinergic (e.g. tiotropium): 7 days · antihistamine (allergy medication): 3 days · inhaled corticosteroid and montelukast: as agreed with the clinic.
• Avoid strenuous exercise in the last 4 hours and caffeine (coffee, tea, cola, energy drinks) on the day of the test, smoking/nicotine in the last hour and a large meal in the last 2 hours.
• An airway infection within the last 2–4 weeks: please call and move the appointment.

Duration

The test itself takes about 45 minutes (six minutes of breathing and measurements for up to 20 minutes afterwards). Expect up to two hours at the clinic in total.

How it is done.

First, spirometry. You then breathe into a mouthpiece at the pace shown on the screen for six minutes. A little carbon dioxide is added to the air, so the rapid breathing does not make you dizzy. Afterwards your lung function is measured after 3, 5, 10, 15 and 20 minutes.

After the test

If the test is positive, if your lung function has not recovered by the last measurement, or if you have symptoms, you are given airway-opening medication and measured again after 10 minutes.

Side effects

The breathing is strenuous, and your mouth becomes dry. Coughing, chest tightness and brief tingling in the fingers or slight dizziness can occur.

When the test cannot be done.

The test cannot be done during pregnancy or with severely reduced lung function, a heart attack or stroke within the last 3 months, uncontrolled high blood pressure or a known aneurysm (a bulge on an artery).

Your result

The result is available straight after the test and is reviewed with you before you leave.

What to bring

• Bring ID, for example your health insurance card or driving licence (app versions also count) or your passport. Your CPR number alone is no longer enough.
• Bring an up-to-date medication list and any earlier lung function measurements.
• Always bring your reliever inhaler.
• Arrive in good time, so you are not out of breath when we start.

Background and sources

• The clinic's own source for medication pauses and preparation (version 20-10-2026) and the clinic's test protocols.
• Hallstrand TS et al. ERS technical standard on bronchial challenge testing: pathophysiology and methodology of indirect airway challenge testing. Eur Respir J 2018;52:1801033.

Asthma testing