Spinal & Epidural Anaesthesia

Epidural and spinal anaesthesia is part of the family of nerve blocks, also referred to as regional anaesthesia. They are used for surgery and also for pain relief.

Type of anaesthetic


An epidural is given into your back (outside the spinal cord) by means of a very fine plastic tube which is inserted through an epidural needle (The needle is removed after the tubing is in place). Local anaesthetic and other pain relieving drugs are given through the tubing to decrease pain.

It works by blocking the pain signals from reaching your brain. The fine plastic tube is taped onto your back and drugs can be given through this fine tube for a number of days. You may have a constant slow infusion or you may have a button to push to give yourself a dose of the pain relief. This is called Patient Controlled Epidural Analgesia (PCEA).

An epidural may be used on its own for your anaesthetic or combined with a general anaesthetic.


A spinal anaesthetic is where a single injection of anaesthetic drugs, is given into the ‘spinal fluid’ of your back by a very fine needle. It works by blocking the pain signals from reaching your brain. It also blocks the movement signals which mean that you will be unable to move your legs while it is working.

This type of anaesthesia is quick to work (usually within 5 to 10 minutes) but only lasts from 1 - 4 hours. You can stay awake or in some cases you can sleep through the surgery by the anaesthetist giving you a sedation or a general anaesthetic as well.

‘A drip’ (IV fluid) is always put into your vein before the spinal or epidural is done. While you will be pain free during an operation, you may feel strange, pressure sensations around the area of the operation.

Potential benefits of an epidural or spinal anaesthetic

• Better pain relief than morphine type drugs

• Less morphine related side effects such as nausea. (if you suffer from morphine type nausea, tell your anaesthetist)

Less risk of lung complications and infections

• Improved bowel recovery after bowel surgery

• Improved blood flow after vascular surgery

• A quicker return to eating and drinking.

Common side effects and complications of a local anaesthetic

• Nerve damage - Nerve damage, if it happens, is usually temporary, and will get better over a period of weeks to months. Damage may cause weakness and/or numbness of the body part that the nerve goes to. Permanent nerve damage rarely happens.

• Bruising (haematoma) - If you take Aspirin, Warfarin, Clopidogrel (Plavix and Iscover) or Dipyridamole (Persantin and Asasantin) you are more likely to get a haematoma as it may affect your blood clotting.

• Failure of local anaesthetic - This may require a further injection of anaesthetic or a different method of anaesthesia to be used.

Less common side effects and complications of a local anaesthetic

• Infection

• Damage to surrounding structures such as blood vessels, nerves and muscles.

Rare Risks and complications of a local anaesthetic

• Overdose of local anaesthetic

• Seizures

• Cardiac Arrest.

Increased risks Risks are increased if:

− you are elderly

− smoke

− are overweight. and if you have the following:

− A bad cold or flu, asthma or other chest disease

− Diabetes

− Heart disease

− Kidney disease

− High blood pressure

− Other serious medical conditions.