Your Spinal Anaesthetic

This guide is written by the Royal College of Anaesthetists. Used here with permission.

Having a spinal anaesthetic for your operation

This leaflet explains:

  • what a spinal anaesthetic is,
  • how it works, and
  • why you could benefit from having one for your operation.

For many operations, patients receive a general anaesthetic which produces a state of controlled unconsciousness during the operation. A spinal anaesthetic (“a spinal”) may be used instead for some operations below the level of the waist. Depending on the type of operation and your own medical condition, a spinal anaesthetic may sometimes be safer for you and suit you better than a general anaesthetic.

You can normally choose:

  • To remain fully conscious.
  • To have some sedation during your operation. This makes you relaxed and drowsy although you remain conscious
  • Or occasionally a spinal anaesthetic may be combined with a general anaesthetic.

Almost any operation performed below the waistline is suitable for a spinal and there are benefits to both you and your surgeon when a spinal is used.

What is a spinal?

A local anaesthetic drug is injected through a needle into the small of your back to numb the nerves from the waist down to the toes for two to three hours.

How is the spinal performed?

  • Your anaesthetist will discuss the procedure with you beforehand on the ward.
  • You will meet an anaesthetic assistant who will stay with you during your time in the theatre.
  • A needle will be used to insert a thin plastic tube (a ‘cannula’) into a vein in your hand or arm and then the staff looking after you will help you into the correct position for the spinal.
  • You will either sit on the side of the bed with your feet on a low stool or lie on your side, curled up with your knees tucked up towards your chest. In either case, the staff will support and reassure you during the injection.
  • The anaesthetist will explain what is happening throughout the process so that you are aware of what is taking place "behind your back".
  • Your anaesthetist will give you the spinal injection and stay with you throughout the operation.
  • As the spinal begins to take effect, your anaesthetist will measure its progress and test its effectiveness.

What will I feel?

  • Usually, a spinal should cause you no unpleasant feelings and should take only a few minutes to perform.
  • As the injection is made you may feel pins and needles or a sharp tingle in one of your legs – if you do, try to remain still, and tell your anaesthetist about it (see side effects and complications).
  • When the injection is finished you normally lie flat as the spinal works quickly and is usually effective within 5–10 minutes.
  • To start with the skin feels numb to touch and the leg muscles are weak.
  • When the injection is working fully you will be unable to move your legs or feel any pain below the waist.
  • During the operation you may be given oxygen to breathe via a lightweight, clear plastic mask to improve oxygen levels in your blood.

Only when both you and the anaesthetist are completely happy that the anaesthetic has taken effect will you be prepared for the operation.

Why have a spinal?

Advantages there may be:

  • Less risk of chest infections after surgery.
  • Less effect on the heart and lungs.
  • Excellent pain relief immediately after surgery.
  • Less need for strong pain-relieving drugs.
  • Less sickness and vomiting.
  • Earlier return to drinking and eating after surgery.
  • Less confusion after the operation in older people.

With a spinal, you can communicate with the anaesthetist and surgeon before, during and after surgery. If an operating camera is being used, you may even be able to watch the operation on television if you wish!

Alternatively, you may decide that you wish to have sedation while the operation is in progress.

Operations a spinal is commonly/often used for

  • Orthopaedic surgery – any major operation on the leg bones or joints.
  • General surgery – hernia repair, varicose veins, piles (haemorrhoids).
  • Vascular surgery – repairs to the blood vessels of the leg.
  • Gynaecology – vaginal repair or operations on the bladder outlet.
  • Urology – prostate removal, bladder operations and genital surgery.

However you may still need a general anaesthetic if:

  • your anaesthetist cannot perform the spinal satisfactorily
  • the spinal does not work satisfactorily
  • the surgery is more complicated than expected.

Side effects and complications

As with all anaesthetic techniques there is a possibility of unwanted side effects or complications. People vary in how they interpret words and numbers. This scale is provided to help:

Very commonCommonUncommonRareVery rare
1 in 101 in 1001 in 1,0001 in 10,0001 in 100,000
  • If something is very common, this means that about one in 10 will experience it.
  • Common means about one in 100.
  • Uncommon means about one in 1000.
  • Rare means about one in 10,000.
  • Very rare means about one in 100,000.

Very common and common side effects

These may be unpleasant, but can be treated and do not usually last long.

Low blood pressure – As the spinal takes effect, it can lower your blood pressure and make you feel faint or sick. This can be controlled with the fluids given by the drip and by giving you drugs to raise your blood pressure. Itching – This can occur as a side effect of using morphine-like drugs in combination with local anaesthetic drugs in spinal anaesthesia. If you experience itching it can be treated, as long as you tell the staff when it occurs. Difficulty passing water (urinary retention) – You may find it difficult to empty your bladder normally for as long as the spinal lasts. Your bladder function returns to normal after the spinal wears off. You may require a catheter to be placed in your bladder temporarily, either while the spinal wears off or as part of the surgical procedure. Pain during the injection – As previously mentioned, you should immediately tell your anaesthetist if you feel any pain or pins and needles in your legs or bottom as this may indicate irritation or damage to a nerve and the needle will need to be repositioned. Headache – There are many causes of headache, including the anaesthetic, the operation, dehydration and anxiety. Most headaches get better within a few hours and can be treated with pain relieving medicines. Severe headache can occur after a spinal anaesthetic. If this happens to you, your nurses should ask the anaesthetist to come and see you. You may need special treatment to settle the headache.

Rare complications

Nerve damage –This is a rare complication of spinal anaesthesia. Temporary loss of sensation, pins and needles and sometimes muscle weakness may last for a few days or even weeks but almost all of these make a full recovery in time. Permanent nerve damage is even more rare and has about the same chance of occurring as major complications of general anaesthesia.

After your spinal

  • Your nurses will make sure that the numb area is protected from pressure and injury until sensation returns.
  • It takes 1.5–4 hours for feeling (sensation) to return to the area of your body that is numb. You should tell the ward staff about any concerns or worries you may have.
  • As sensation returns you may experience some tingling in the skin as the spinal wears off. At this point you may become aware of some pain from the operation site and you should ask for more pain relief before the pain becomes too obvious.
  • As the spinal anaesthetic wears off, please ask for help when you first get out of bed.
  • You can normally drink fluids within an hour of the operation and may also be able to eat a light diet.

Frequently asked questions

Q Can I eat and drink before my spinal?

You will need to have an empty stomach before your operation and you must follow the same rules as if you were going to have a general anaesthetic. This is because it is occasionally necessary to change from a spinal anaesthetic to a general anaesthetic. The hospital should give you clear instructions about fasting.

Q Must I stay fully conscious?

Before the operation you and your anaesthetist can decide together whether you remain fully awake during the operation or would prefer to be sedated so that you are not so aware of the whole process. The amount of sedation can be adjusted so that you are aware but not anxious. It is also possible to combine a spinal with a light general anaesthetic.

Q Will I see what is happening to me?

Sometimes you can choose. Normally a screen is placed across your upper chest so that you see nothing when surgery starts. Some operations use video cameras and telescopes for “keyhole” surgery and many patients like to see what is happening to them on the video screen. You will be aware of the “hustle and bustle” of the operating theatre when you come in. Once surgery starts noise levels drop. You will be able to relax, with your nurse and your anaesthetist looking after you. Some patients like to wear personal stereo headphones to listen to their own choice of music during the operation. The options available to you will vary, depending on a number of factors to do with your operation. You will be able to discuss all these possibilities with your anaesthetist at the preoperative visit.

Q Do I have a choice of anaesthetic?

Yes. Your anaesthetist will assess your overall preferences and needs for the surgery and discuss them with you. If you have anxieties regarding the spinal then these should be answered during your discussions, as it is usually possible to accommodate individual patients’ wishes and still use a spinal anaesthetic.

Q Can I refuse to have the spinal?

Yes. If, following discussion with your anaesthetist, you are still unhappy about having a spinal anaesthetic you can always say no. You will never be forced to have any anaesthetic procedure that you don’t want.

Q Will I feel anything during the operation?

Your anaesthetist will not permit surgery to begin until you are both convinced that the spinal is working properly. You will be tested several times to make sure of this. You should not feel any pain during the operation but you may well be aware of other sensations such as movement or pressure as the surgical team carry out their work.

Q Should I tell the anaesthetist anything during the operation?

Yes, your anaesthetist will want to know about any sensations or other feelings you experience during the operation. They will make adjustments to your care throughout the operation and be able to explain things to you.

Q Is a spinal the same as an epidural?

No, although they both involve an injection of local anaesthetic between the bones of the spine in the small of your back, the injections work in a slightly different way.

Q Where can I learn more about spinals?

This leaflet is designed to give you a brief overview about your spinal anaesthetic. If you would like more detailed information, speak to your anaesthetist or contact the anaesthetic department in your local hospital or the organisations listed at the bottom of this leaflet.

Questions you may like to ask your anaesthetist

  • Who will give my anaesthetic?
  • Do I have to have this type of anaesthetic?
  • Have you often used this type of anaesthetic?
  • What are the risks of this type of anaesthetic?
  • Do I have any special risks?
  • How will I feel afterwards?

Useful organisations

Association of Anaesthetists of Great Britain and Ireland

21 Portland Place
London W1B 1PY
Phone: +44 20 7631 1650
Fax: +44 20 7631 4352

This organisation works to promote the development of anaesthesia and the welfare of anaesthetists and their patients in Great Britain and Ireland.

Royal College of Anaesthetists

Churchill House
35 Red Lion Square
London, WC1R 4SG
Phone: + 44 20 7092 1500
Fax: + 44 20 7092 1730

This organisation is responsible for standards in anaesthesia, critical care and pain management throughout the UK.

The European Society of Regional Anaesthesia and Pain Therapy

c/o Department of Anaesthetics
The Alexandra Hospital
Woodrow Drive
Worcestershire B98 7UB
Tel/Fax: 01527 512047

This organisation works to further regional anaesthesia in Europe.

This guide was written by The Royal College of Anaesthetists, Churchill House, 35 Red Lion Square, London WC1R 4SG.
© 2002, RCoA (3rd edition - May 2008). Copyright for this article is with the Royal College of Anaesthetists.