Please read this page carefully
This page will describe the different tests performed by the respiratory physiology team at Leeds Children’s Hospital in the Paediatric Respiratory and Cystic Fibrosis Unit.
Please refer to the relevant section for the test you are due to have and see section below for important instructions for before your appointment.
For all tests, please read this page carefully before coming to your appointment.
For each test to be performed it is important to carefully read the following pre-test instructions and act accordingly.
Before you leave for your appointment:
For the tests to be carried out successfully, please do not:
- Exercise for 30 minutes before.
- Be exposed to smoking or vaping for at least one hour before the test (and preferably never)
- Wear any tight clothing that may restrict your breathing.
Please contact the department if you have recently experienced any of the following:
- A new cough that is not typical of your usual condition and/or high temperature.
- Attended A&E within the last one week.
- Chest infection / coughing up blood / burst ear drum within the last two weeks.
- Collapsed lung, broken ribs, blood clot, stroke or heart attack within the last six weeks.
- Any surgery or procedures within the last 12 weeks.
- Chest pain on the day of your appointment.
If prescribed, please bring your blue inhaler (reliever) and spacer with you.
Spirometry
A Spirometry test (also known as “blows”) measures how much air you can breathe out in one forced breath and how fast. We will ask you to take in a big breath as full as you can, then blow out as hard and as fast as you can until it is impossible to blow out any more air. You will need to breathe through a mouthpiece and wear some nose pegs for the test.
Do I need to stop any medications before spirometry?
Please try to avoid taking the following relievers for 4 hours prior to your test:
- Salbutamol / Ventolin / Airomir / Salamol (blue).
- Bricanyl (blue or white with blue twisty bottom).
If you can’t manage without your inhaler, please use it and make a note of the time.
Please continue to take all other prescribed medications as normal.
If prescribed, please bring your blue inhaler (reliever) and spacer with you.
Full Pulmonary Function Test
A Full Pulmonary Function Tests is made up of three smaller tests. You will be seated for the whole test breathing through a mouthpiece. You will also be asked to wear a nose clip. The first two tests (spirometry and gas transfer) are performed while sitting in a chair in front of a computer. The third test (static lung volumes) is performed while sitting inside a glass cubicle. Each test will be repeated a few times.
- Spirometry – measures how much air you can breathe out in one forced breath and how fast. For this test we will ask you to take in a big breath as full as you can, then blow out as hard and as fast as you can until your lungs are empty.
- Gas Transfer – looks at how well the lungs transfer gases from the air into the blood stream. We will ask you to blow out gently until your lungs are empty then take a big breath in as full as you can and hold your breath for 8-10 seconds before blowing out gently again.
- Static Lung Volumes – measures the total size of your lungs. For this test you will be inside a glass cubicle and the door will need to be closed, only for a few minutes. We will ask you do some normal breathing, then some panting manoeuvres against a shutter before blowing out for as long as you can and then taking in a breath as full as you can.
Do I need to stop any medications?
Please try to avoid taking the following relievers for four hours prior to your test:
- Salbutamol / Ventolin / Airomir / Salamol (blue).
- Bricanyl (blue or white with blue twisty bottom).
If you can’t manage without your inhaler, please use it and make a note of the time.
Please continue to take all other prescribed medications as normal and bring a list of these with you.
If prescribed, please bring your blue inhaler (reliever) and spacer with you.
Spirometry and Gas Transfer
A Spirometry and gas transfer test may be performed like a Full Pulmonary Function Test but without static lung volumes. Please see instructions above for Full Pulmonary Function Test.
For Bronchodilator Responsiveness and Mannitol Challenge Tests, it is very important to follow the instructions about stopping certain medications prior to your appointment.
Please read these sections very carefully to avoid a wasted appointment, as we will not be able to perform the tests if you have taken the named medications within the stated time periods.
If you have any questions please contact the department on 0113 392 7125 (Mon-Fri 08:30-16:30).
Back to topBronchodilator Responsiveness (Spirometry and BDR)
A bronchodilator responsiveness test (often referred to as reversibility) measures how your airways respond to the bronchodilator medication salbutamol.
You will be asked to perform Spirometry first. Then if appropriate, we will administer four puffs of salbutamol to you through a spacer. We will then wait 10-15 minutes and repeat the Spirometry test.
Do I need to stop any medications before Spirometry and Bronchodilator Responsiveness?
Please see the table below for a list of inhalers and how long each inhaler needs to be withheld for:
If you can’t manage without your inhaler, please use it, make a note of the time, and contact the department as we may need to reschedule your appointment.
Please continue to take all other prescribed medications as normal.
If prescribed, please bring your blue inhaler (reliever) and spacer with you.
If you regularly use inhalers or nebulisers then please avoid taking the following medications for the time period indicated:
Required medication withholding for reversibility
How long to stop medication before bronchodilator responsiveness test?
- Short acting beta-2 agonists (SABA) e.g. Salbutamol, Ventolin – 4 hours
- Short-acting muscarinic antagonists (SAMA) e.g. Ipratropium/ Atrovent – 12 hours
- Long-acting beta-2 agonists (LABA) e.g. Salmeterol/ Serevent, Formoterol/ Foradil – 24 hours
- Combination inhalers- Inhaled Corticosteroids (ICS) + LABA e.g. Seretide, Symbicort, Fostair – 24 hours
- Relvar Ellipta – 36 hours
- Long-acting muscarinic antagonists (LAMA) e.g. Spiriva, Seebri, Braltus – 48 hours
- Combination inhalers- LABA + LAMA e.g. Spiolto, Anoro – 48 hours
- Combination inhalers- ICS + LABA + LAMA e.g. Trimbow, Trelegy – 48 hours
*Please see information above about withholding medications
Note: steroid only inhalers (eg. orange and brown inhalers) do not need to be withheld.
Back to topMannitol Challenge Test
A mannitol challenge test looks to see whether you have sensitive airways which can be irritated. We will firstly ask you to perform spirometry (see section on spirometry).
Then if the spirometry is acceptable, we will ask you to breathe in an increasing amount of mannitol through an inhaler (see figure 3). Spirometry will be repeated to see the effect that the mannitol has on your airways. There are potentially nine levels of inhaling mannitol and performing spirometry to see the effect of mannitol on your airways. Each level has an increasing amount of mannitol. The test ends if there is a significant change in the amount of air you can blow out, or after nine levels. At the end of the test we will give you some salbutamol (as described in Bronchodilator Responsiveness) to relieve any symptoms you may have experienced. After 10-15 minutes, we will repeat spirometry and ensure that your breathing is as normal before you leave.
Mannitol may cause you to cough and have a dry mouth; water will be provided. Occasionally people feel a bit tired after mannitol challenge tests. You will be offered the option to wait in the department if you wish.
Please allow 60 minutes for this test.
Do I need to stop any medications before Mannitol Challenge?
Please see the table below for a list of inhalers and other medications that can affect this test and how long each needs to be withheld for:
If you can’t manage without your inhaler or medication, please take them, make a note of the time, and contact the department as we may need to reschedule your appointment.
Please continue to take all other prescribed medications as normal.
If prescribed, please bring your blue inhaler (reliever) and spacer with you.
If you regularly use inhalers, nebulisers, antihistamines or leukotriene receptor antagonists then please avoid taking the following medications for the time period indicated:
Required medication withholding for mannitol challenge
How long to stop medication before mannitol challenge test?
- Short acting beta-2 agonists (SABA) e.g. Salbutamol/ Ventolin – 8 hours
- Inhaled corticosteroids (ICS) e.g. Qvar/ Beclomethasone, Pulmicort/ Budesonide – 12 hours
- Short-acting muscarinic antagonists (SAMA) e.g. Ipratropium/ Atrovent – 12 hours
- Long-acting beta-2 agonists (LABA) e.g. Salmeterol/ Serevent – 24 hours
- Theophylline – 24 hours
- Combination inhalers: Inhaled Corticosteroids (ICS) + LABA e.g. Seretide, Symbicort, Fostair – 24 hours
- Relvar Ellipta – 36 hours
- Long-acting muscarinic antagonists (LAMA) e.g. Spiriva, Seebri, Incruse – 3 days
- Combination inhalers: LABA + LAMA e.g. Spiolto, Anoro
– 3 days - Combination inhalers: ICS + LABA + LAMA e.g. Trimbow, Trelegy – 3 days
- Antihistamines – 3 days
- Montelukast (and other leukotriene receptor antagonists)
– 4 days
*Please see information above about withholding medications
Back to topHypoxic Challenge Test
A hypoxic challenge test creates conditions like an aircraft at altitude, where there is slightly less oxygen available. It will help your consultant to decide whether you need extra oxygen during a flight.
At high altitudes blood oxygen levels fall in everyone and some people may feel a little breathless. In most people this has no health effect. But if you already have low blood oxygen levels because of your lung condition, then the extra dip that happens while you are in the plane could cause breathlessness and discomfort for you.
You will either be asked to breathe a gas mixture (through a face mask) which creates the oxygen level of an aeroplane (15%), for up to 20 minutes or you will be inside a glass cubicle for up to 20 minutes which will have the oxygen level of an aeroplane (15%). During this test we will monitor your pulse rate and oxygen levels. If your oxygen levels drop below a certain level we may continue the test while giving supplemental oxygen through a nasal cannula. Occasionally people feel dizzy or faint during these tests. If this happens, please tell the technician. Small children may be accompanied by a parent/guardian inside the glass cubicle and the parent/guardian will also be monitored for safety.
Please allow 60 minutes for this test.