Spinal & epidural.

How they work

A fine needle places local anaesthetic near the nerves in your lower back, blocking pain signals from travelling from the lower body to the brain. By using this technique, we can dramatically lower the dose of strong pain relief drugs needed while you are having your operation. This means much less side effects from these drugs, which typically appear at those higher doses. It also likely means less stress on your heart during and after the procedure, as well as less depression of your breathing once you are awake.

What’s the difference between a spinal and an epidural?

A spinal is a single injection of local anaesthetic into the fluid around the spinal cord, injected over a few seconds. The effects will last around 2-5 hours depending on the desired duration we are aiming for, achieved by adjusting the dose we give during the spinal procedure.

An epidural is similar to a spinal anaesthetic, but the numbing medicine is placed just outside the fluid-filled covering around the nerves in your back.
A very fine, soft tube is then left in place so we can give more numbing medicine if needed. Only a short part of the tube sits under the skin; the rest is gently secured with tape along your back, with the end usually brought up towards your shoulder.

(Spinals are more often used for surgical procedures.

Epidurals are not too commonly used in the majority of situations, other than during labour. They are of benefit in labour, because we can continually add more local anaesthetic through the epidural as your labour progresses. If the labour progresses into the need for a c-section procedure, a final stronger dose of local anaesthetic can be given again through the epidural, which will result in a much stronger block that is needed for the procedure.)

What it feels like

After the skin is numbed you may feel pressure, but not sharp pain, as the block is placed. Most patients say that it is comparable or much more tolerable to the IV drip being inserted in the arm!

Once it is done and working, your legs grow warm, heavy, sometimes tingly, and numb over a few minutes. There will most often be light sedation/ deep sedation after the spinal is performed.

The spinal / epidural may also be supplemented with a nerve block. See the nerve block info page!

Will I be awake or asleep during the spinal / epidural?

You are awake during the spinal or epidural procedure in almost all instances. If you are having a c-section, you will benefit from being awake during delivery of your baby, and so we do not give extra sedating medications after.
If you are having a knee replacement / hip replacement surgery, you will usually not recall the spinal procedure occurring afterwards. This is because we administer a small dose of relaxing agent in the IV line just before the spinal is performed. For this reason, you may remember sitting up on the bed ready for the spinal, but nothing after that. You will be relaxed and talking to us during the insertion, but most often won’t have recollection of that conversation afterwards!

How safe is having an epidural / spinal?

It is very safe to have an epidural and spinal. Most anaesthetists have performed hundreds if not thousands of these during their career. The more common risks include: partial block / need to redo procedure later / mild pain over the injection site / headache in around 1-2% of cases in the days that follow / mild bruise around insertion site. The more serious risks are very rare and we would only see these a few times if any during our career. See here

Afterwards

Sensation and movement return gradually as the block wears off. In the rare scenario, an epidural catheter may be inserted, through which we can deliver top-ups of local anaesthetic, which can keep you comfortable for hours or days after the procedure. We watch your blood pressure and your legs closely until everything is back to normal.

When the spinal / epidural has worn off, there will be strong pain relief medications ready for you to ask for in your medication chart. Please ask for these should your comfort levels dissipate as the block wears off!