Anaesthesia explained

Published: 02/08/2019

Ways of taking pain relief

Your anaesthetist will be able to talk with you about which types of pain relief are appropriate for you.

Tablets or liquids to swallow 

These are used for all types of pain. They take 30 minutes to work and are best taken regularly. You need to be able to eat and drink without feeling sick for these drugs to work. 

Injections into a muscle 

These are not needed very often, but may be prescribed as an extra form of pain relief if you unexpectedly have a lot of pain. They may be given into your leg or buttock muscle and take 10 to 15 minutes to work.

Suppositories  

These waxy pellets are placed in your rectum (back passage). The drug dissolves and is absorbed into the body, taking 10 to 20 minutes to work. They are useful if you cannot swallow or feel very sick. 

Intravenous pain relief (into a vein)

During your anaesthetic and in the recovery room your anaesthetist and nurses may give you drugs into your cannula. This means they work more quickly than if the same drugs are given as a tablet or injection into a muscle. 

Pain relief drugs

Two basic types of pain relief drug are given commonly.

  • Paracetamol.
  • Anti-inflammatory medicines (for example, ibuprofen and diclofenac).

Each of these medicines can be given in some of the ways listed – as a tablet or liquid to swallow, by an injection into a muscle, as a suppository, or into a vein. They can be used together as they belong to different chemical groups. 

Anti-inflammatory drugs have a number of side effects which make them unsuitable for some people. Your anaesthetist will consider this before prescribing them for you.

Opiate pain relief medicines 

These drugs are used after operations that are expected to cause considerable pain. 

Morphine, diamorphine, pethidine, codeine, tramadol and oxycodone are all opiate pain-relief medicines. They may be given as a tablet or liquid to swallow, as an injection into a muscle, or intravenously into your cannula. 

Side effects are common with these drugs. These include feeling sick, vomiting, itching, drowsiness and, if used over a few days, constipation. Larger doses can cause very slow breathing and low blood pressure. The nursing staff will watch you closely for all of these side effects. If they happen, other treatments will be given to keep you safe. 

Your reaction to opiates will affect you considerably. Anti-sickness drugs will be given as well. One in three people find opiates unpleasant, but they are the most effective pain-relief medicines in many circumstances. 

Other ways of giving pain relief 

Patient-controlled analgesia (PCA) 

This is a system which allows you to control your own pain relief. Opiate drugs are put into a pump which is connected to your cannula. The pump has a handset with a control button which you will be shown how to operate. When you press the button, a small dose of the opiate drug goes straight into your cannula.

Using a PCA allows you to help yourself to a small dose of pain relief very frequently. The anaesthetist sets the dose and also a minimum time limit between doses (usually five minutes). After that time has passed, you can decide whether you want another dose. The drug goes straight into a vein, and so works very quickly. You can continue to press the button at five-minute intervals until your pain is reduced to a suitable level. You can then have further doses to top up your pain relief as you need them, and keep yourself comfortable. 

Your nurses watch you carefully while you are using a PCA, to make sure that you are reacting safely to the pain-relief medicine.  

There is evidence showing that patients benefit from being in control of their own pain relief. This type of pain relief is at least as safe, or safer, than other ways of giving opiate pain relief. 

Local anaesthetic catheters 

These are fine tubes which the surgeon can place under the skin, near to your surgical wound or to the nerves that supply the area. Not all operations are suitable for having local-anaesthetic catheters. 

Each catheter is attached to a pump that contains local anaesthetic. The local anaesthetic blocks pain signals from nearby nerves and should reduce your pain. The pump can be kept running for several days. 

These catheters do not always relieve pain well, but there is evidence which shows that they are generally helpful, with few side effects.

An epidural catheter for pain relief 

This is a system for pain relief for operations on the lower body. 

A fine tube (epidural catheter) is placed into your back, using a needle. A pump is used to run local anaesthetic continuously into the epidural catheter.  This makes the lower half of your body become numb. The numbness lasts as long as the catheter is in place and the pump is running. When the catheter is removed, feeling in the area returns to normal. 

An epidural can be used for pain relief for most major operations on the lower body. For more information, please see our leaflet on Epidural pain relief after surgery.

Pain relief at home 

Your anaesthetist or doctors and nurses on the ward (or both) will make a plan for your pain relief at home.

  • You may be asked about pain relief drugs that you already have at home, such as paracetamol. It is a good idea to stock up on pain-relief tablets before you come into hospital. Staff at the pre-assessment clinic will be able to advise you about which pain-relief drugs may be useful. 
  • If appropriate, you may be given a supply of pain-relief drugs to take home with you.

You may be advised to take several different types of pain relief. It is important that you understand how to use the different drugs and that you are aware of possible side effects. This will be explained to you. It is helpful if a relative or friend listens when this information is given, to help you remember what to do. Ideally you will receive written information as well. 

Who can give me advice when I am at home?  

Before you leave the ward, you should make sure you know how and who to contact if you develop significant pain or other problems at home. You may get this information from:  

  • the nurse who arranges your discharge from hospital
  • the doctors on the ward, or
  • your surgeon or anaesthetist.

This is especially important if you go home on the day of your operation.