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Analgesia: Patient controlled

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Information on patient controlled analgesia

Pain is a personal matter. The amount and type of pain relief required varies between people, even for the same type of injury or surgery.

What is PCA?

Patient controlled analgesia, or PCA, is a method of pain control that allows you to give yourself some pain relief as and when you need it.

Patient Controlled Analgesia

Patient Controlled Analgesia System
example of a PCA pump

How does a PCA work?

The PCA system is attached to you through an infusion into a vein in your arm. You control the system with a hand held button (other ways of activating the system is available if you do not have full use of your hands). When you feel pain, you should push the button on your PCA handset and a small amount of pain relief will be delivered directly into your bloodstream. A reduction in pain should be felt within a few minutes; if not you can press the button again once the green light is visible on the handheld device.

Who controls the PCA?

You are the only person who knows when you are in pain so you are the only person who should press the PCA button.

Is PCA safe?

The PCA has alarms set to alert your nurse of any problems. It is carefully programmed to deliver only a specific amount of pain relief so you cannot overdose. The nurses and doctors will follow your progress carefully. There will be frequent checks on your blood pressure, pulse, breathing and level of sedation.

Is the PCA pain relief addictive?

When used for a short periods of time only, the pain relief via the PCA is not addictive. Pain control is important in order to avoid other health problems such as chest infection or deep vein thrombosis.

Your part in controlling pain

Your nurse will ask you to rate your pain using numbers, words or by using an assessment chart with faces on it. This assessment will indicate the amount of pain you are experiencing. Using numbers, pain would be scored as follows.

0 no pain

10 worse pain imaginable

Your reports will help the nurses and doctors to make necessary adjustments to your care.

It is realistic to expect some pain when coughing or moving about in bed but it should never be more than mild (bearable). Pressing the PCA button before mobilising, deep breathing or coughing will help to prevent your pain level from rising. Use your PCA to keep your pain level in the mild and bearable range (score 0 – 4) just before and during movement.

Are there any side effects?

All drugs have some side effects. The most common side effects with a PCA are:





These side effects do not occur in everybody. If they occur, report them to the nurse or doctor looking after you. Medications can be given to counteract the side effects.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151