Advanced Spirometry & Lung Function

Advanced lung function testing is a set of breathing tests that measure air flow, the total volume the lungs can hold, and how well oxygen passes from the lungs into the blood. Together they build a detailed picture that spirometry alone cannot give. At Allergy Asthma Foundation it is carried out by an experienced team using current equipment and protocols, with clear information given before, during and after so that you know what to expect at every stage.

This page explains why the procedure is done, how to prepare, what happens on the day, and what recovery and follow-up involve. Your own consultant will go through the details that apply to your situation and answer any questions before you agree to go ahead.

Why it is done

Advanced spirometry and lung function testing is usually recommended for one or more of the following reasons:

• Diagnosing and grading asthma, COPD and restrictive lung disease
• Explaining breathlessness that does not fit a simple pattern
• Assessing fitness of the lungs before surgery
• Monitoring conditions such as pulmonary fibrosis over time
• Checking the response to a new treatment

It is only offered when the expected benefit clearly outweighs the risks, and the decision is always made together with you. If a simpler test or treatment would answer the question or relieve the problem, that is tried first.

How to prepare

• Bring a list of your current medicines and any earlier results for the same test.
• Ask the team whether any medicine needs to be paused beforehand — for some tests, antihistamines or inhalers are held for a short, specified time.
• Wear comfortable, loose clothing.
• Avoid a heavy meal, vigorous exercise and strong coffee in the hour before the test.
• Allow a little extra time; the appointment includes explanation and practice, not only the measurement itself.

What happens on the day

1. For spirometry you blow out hard and long into a mouthpiece with a nose clip on, repeated until consistent.
2. For lung volumes you sit inside a clear cabin and pant gently against a shutter, or breathe a harmless tracer gas.
3. For gas transfer you take a single deep breath of a test gas mixture, hold it briefly and breathe out.
4. The reliever-inhaler response may be checked by repeating spirometry after a dose.
5. The full set of tests takes about 45 minutes including rest between manoeuvres.

After the procedure

The tests are effort-based but safe. You may feel briefly light-headed after the forced breaths. You can drive and return to work immediately. Bring your inhalers and follow any advice about holding them beforehand.

You will be given written instructions covering activity, wound or puncture-site care where relevant, which medicines to restart and when, and the warning signs that mean you should contact us or attend the emergency department. A follow-up appointment or a phone review is arranged before you leave.

Benefits and risks

The main benefit is a clear answer or effective treatment that changes what happens next — a firm diagnosis, a blocked passage reopened, symptoms brought under control, or a condition safely monitored over time. For most people the procedure is straightforward and complications are uncommon.

No procedure is entirely without risk. The ones to be aware of for this treatment include:

• Transient dizziness, cough or chest tightness from the forced manoeuvres
• Results depend on effort and technique, so an unclear test is sometimes repeated
• Rarely, the forced breathing triggers wheeze, which is treated on the spot

The team is trained and equipped to recognise and manage these, and the consent discussion covers how likely each is in your case and what is done to reduce it.

Results and follow-up

A physiologist checks the quality of every measurement and the reported results are sent to your consultant within a few working days, with urgent tests reported sooner. Your consultant explains what the result means in the context of your symptoms and examination, and sets out the next step — reassurance and discharge, a change of treatment, a further test, or a planned review. With your consent a summary is sent to your family doctor so that everyone caring for you is working from the same plan.

Questions patients ask

Do I need a referral?

You can book a consultation directly to discuss whether advanced spirometry and lung function testing is right for you. The procedure itself is arranged by the consultant after that discussion, once you have had time to consider it.

Will it hurt?

Discomfort is kept to a minimum with local anaesthetic, sedation or pain relief as appropriate to the procedure. The team will tell you exactly what you are likely to feel and will stop or pause if you need them to.

How long will I be at the hospital?

Most people are in and out within a few hours; where an overnight stay or a longer recovery is expected, that is explained clearly when the procedure is booked so you can plan around it.

To arrange advanced spirometry and lung function testing at your nearest AAF centre, book a consultation online or request a callback. Please bring a list of your current medicines and any previous test results or discharge summaries.