Your surgeon and anaesthetist are responsible for your well-being during and after your surgery. They must be sure that you are fit enough to undergo the operation. You may have tests such as a chest x-ray and an ECG (electrocardiogram) to assess your lungs and heart. Your kidney function may be checked with blood tests if you are likely to have a long operation, as this may put strain on the kidneys.

If you are not considered to be fit enough for a general anaesthetic, it may still be possible for you to have surgery. Some operations can be done under local anaesthetic or epidural (a spinal anaesthetic). With these techniques, you will be awake during the operation, but will not feel any pain.