What is Cardiopulmonary Exercise Testing (CPX)?
This is a medical test which allows the anaesthetic team to see how your lungs, heart and muscles react to exercise. This will enable us to understand the risk of surgery and plan the level of care that you will require following your operation.
What are the benefits of the test?
A Cardiopulmonary Exercise Test (CPX) stresses your heart and lungs in a controlled environment. The data helps us to plan how to look after you during and after your surgery. We can also tell you more about the risks of your surgery using the results. The test is not a “pass or fail” test but may inform us that a different approach to your surgical problem would reduce your risk.
What are the risks of the test?
As with all medical tests, there is the possibility of unwanted side effects or complications. The risks of these are the same as for mild exercise. About 1 in 1000 patients develops complications which include abnormal blood pressure, fainting, problems with heart rate or rhythm. In exceptional circumstances there can be serious complications such as a heart attack or stroke.
How is a CPX test performed?
We have no designated changing area so come dressed in cool, comfortable clothing that you can move around in.
Your height and weight will be measured. A member of staff will apply stickers to your chest so that your heart can be monitored and a saturation probe (a monitor that measures the content of oxygen in your blood) placed on your finger. Your lung capacity will be measured at the start of the test using a tube that measures the volume of air you breathe in and out.
A mask will then be fitted. It is very important that the mask makes a good seal with your face and for this reason we would advise men to reduce or remove facial hair if at all possible.
You will then be given a period of rest on the bike before being asked to pedal against no resistance for 2-3 minutes. The bike will then slowly increase the resistance until you feel unable to pedal any more. The test is designed so that the more you are able to do, the more information is gained. However, the test may be stopped if you get too tired, or if we get all the information we need. The test usually takes 8-12 minutes.
How long will the appointment take?
The whole appointment will take up to an hour. This will include time for explanations, consent, history and examination, the test itself and a discussion with you about the results.
Where will the test take place?
In the pre-assessment clinic on level 3 of the Peter Smith surgery centre.
Can I eat before the test?
Yes, however we would advise against a large meal immediately prior to the test. It is recommended you have a light meal up to two hours before the test.
Should I take my usual medications prior to the test?
Yes.
When will I be told the result of the test?
The test will be discussed with you once you have recovered. A copy of the test and discussion will be sent to you, your GP, Surgeon and Anaesthetist. You will be given ample opportunity to ask any questions at the time of the test.
Will anyone else see my tests?
The CPX test will only be seen by those directly caring for you. We may ask for your permission to use the data obtained from your test for research purposes. The data will be anonymised, and it will not be possible to identify you from the data.