Epidural Anaesthesia

An epidural provides pain management by blocking the nerves carrying pain from the womb and birth canal. This is achieved by injecting local anaesthetic into the space surrounding the spinal cord. The local anaesthetic is injected down a small plastic tube, a catheter, which passes between the bones in the lower back.

What are the risks of an epidural?

There are some risks associated with epidurals, the most significant risks are headache and nerve damage.

Severe headache - is caused by accidental puncture of the sack of fluid surrounding the spinal cord during insertion of the epidural. The severe headache may last for days or weeks if untreated. The headache often improves with treatment such as lying flat, drinking plenty of fluid and taking regular painkillers. In some patients additional treatment may be needed which involves a further epidural injection.

Nerve damage - is a rare complication of epidural insertion. Temporary nerve problems are common whether an epidural is used or not. This is usually a minor problem, for example a numb patch on the thigh, which gets better over a few days. It often goes unnoticed. Direct nerve injury from epidurals is possible. Once again, this may result in a temporary patch of numb skin and usually gets better within a couple of months. Permanent paralysis is very rare.

For more information on risks and likelihood visit www.labourpains.com

Are there any side effects of an epidural?

The epidural may cause a drop in blood pressure, which may make you feel faint and nauseated which is easily treatable. Other effects include shivering or itching, which are usually short term. You may temporarily loose the sensation of a full bladder therefore your midwife will check for this at intervals, and it may be necessary to insert a small tube into the bladder to drain the urine. This is removed as soon as the bladder is empty.

Epidurals may cause temporary bruising. The likelihood of having long-term back problems after delivery is the same whether or not you have an epidural for labour.

Does and epidural effect my baby?

Epidurals have very little effect on your baby. A large drop in blood pressure may temporarily affect the baby, but is easily treated.

As you will no longer be aware of painful contractions, the midwife will feel the strength of your contractions by laying a hand on your tummy. In addition to this, the frequency of your contractions and your baby’s heartbeat will be continuously monitored using a cardio-tocograph monitor (CTG machine).

The total time course of labour may be prolonged. Epidurals have been associated with a higher rate of forceps or ventouse delivery; this risk is reduced with modern solutions of local anaesthetic. There is no increased risk of caesarean section.

What are the advantage of an epidural?

In addition to providing pain management in labour epidurals have been shown to reduce, or reverse, the body’s stress responses to pain.
This means that breathing returns to normal, the muscles begin to relax, blood pressure falls, the heart has to work less hard and blood flow to the womb may be improved. When an epidural catheter is in place it is very easy to provide pain management for other procedures e.g. caesarean sections or forceps deliveries.

How is an epidural given?

Occasionally there is a medical reason, which does not allow the use of an epidural. The anaesthetist will be happy to discuss this and advise on the other options available to you.

Before putting in the epidural, the anaesthetist will ask you some questions and discuss the risks and benefits of the procedure.

If you are happy to continue, then a cannula (small plastic tube) will be put into a vein in your hand or arm to allow fluid and any necessary medications to be given into a vein. Next you will be asked to position yourself for the epidural. This involves curling up into a ball, either sitting up or lying on one side. Your back is cleaned with cold fluid and the skin made numb with an injection of local anaesthetic. This stings for a few seconds. A needle is then passed between the bones in your back to find the space surrounding the spinal cord. It is very important to lie as still as possible at this stage to avoid any complications.

The anaesthetist will try to work in between your contractions and your midwife will help with this. A fine epidural catheter is then passed through the needle and the needle removed. Sometimes the catheter touches a nerve and causes a brief shock or “twinge” that passes into the leg. This is normal and short lasting. Finally, the catheter is taped down onto your back and is ready for use.

This is a technically difficult procedure and it usually takes about 20 minutes to insert the catheter. In people with more difficult backs, it may take longer or not be possible at all. Once the catheter is in, the local anaesthetic will take about 20 minutes to reach its full painkilling effect. 

The epidural will make your tummy feel numb and take away most of the pain of your contractions. Your legs may feel weak and heavy and for this reason you will not be allowed to walk until the effects wear off.

A dose of local anaesthetic usually lasts for about one hour. As it wears off you will start to feel pain from your contractions again.

At this point your midwife can easily give you another dose (a ‘topup’) via the epidural catheter.

In most women the epidural will be very effective. However, for some the epidural will not provide pain management immediately, and may require adjustment. Sometimes, it may need to be replaced.

What happens if I need an operation?

If for any reason you require an operation such as a caesarean section, the epidural can usually be used instead of a general Anaesthetic which is safer for you and your baby.

If you don’t want any pain management you are free to say so. If you decide you do want pain management ask for it as soon as you feel you need it don’t wait to be offered.

For more information visit www.nhs.uk/conditions/pregnancy-and-baby/pages/pain-relief-labour