This leaflet is aimed at anyone undergoing foot surgery who is thinking about having a nerve block for their operation. A nerve block involves the injection of local anaesthetic around nerves in the foot to numb them. Often this is done instead of a general anaesthetic.
What are the benefits of having a nerve block?
- Excellent pain relief during and after surgery
- Less need for strong pain medicines which can make some people feel drowsy or sick
- Avoid a general anaesthetic and its associated risks and side effects
- Can often eat and drink sooner after surgery than with a general anaesthetic
- Can often recover quicker and leave hospital sooner
What to expect
A nerve block is a type of anaesthetic or pain relief frequently used for surgery on the foot or toes. It involves the careful injection of local anaesthetic around the nerves that provide sensation to this area to make them numb for surgery. The injections can be around the back of your knee, or around the lower part of your leg or ankle.
Nerve blocks are performed by anaesthetists trained in the technique and they will discuss the procedure fully with you. A small intravenous line (drip) is placed in the hand or arm and other routine monitoring is attached.
First, the skin is cleaned and then made numb with a small amount of local anaesthetic. A fine needle is then carefully guided towards the nerves using an ultrasound machine. More local anaesthetic is then injected around the nerves to ‘block’ them. Most people find that having the block performed is no more uncomfortable than having an intravenous drip inserted but sometimes sedation can be used.
Your foot will start to feel warm, tingly and heavy soon after the injection. Your anaesthetist will carefully check the block before surgery starts. Occasionally a top-up of local anaesthetic is needed to ensure the block is complete.
During your operation
A screen will be placed so that you cannot see the operation, unless you want to. A member of staff will be available to answer any questions and ensure you are comfortable. Before surgery, a tight band (tourniquet) may be wrapped around your ankle. This helps prevent bleeding in the area during surgery.
When the operation starts, it is normal to sometimes feel some movement or touch, but you should not be able to feel any discomfort or pain. An iPad will be offered to you to watch or listen to music throughout your operation.
If you prefer, sedation can be provided instead, which will make you relaxed and sleepy while you remain conscious. Occasionally, it will be planned for you to have a general anaesthetic in addition to the nerve block. This depends on the type and length of your operation and this will be fully discussed with you beforehand.
- Occasionally a block will not work well enough for your operation and a general anaesthetic may be required. In this situation the block may still provide good pain relief afterwards although, if necessary, other painkillers can also be used to keep you comfortable.
- There is a small risk of nerve damage after any operation regardless of the type of anaesthetic used. This is due to the operation, the position you lie in, or the use of a tourniquet. Swelling around the operation site, or other medical conditions such as diabetes, may also lead to nerve damage.
- The risk of long-term nerve damage following a nerve block is approximately 1 in 5000 cases. About 0.5% to 1% of patients may notice a prolonged patch of numbness, tingling or weakness in the affected area (lasting > 48 hours postoperatively). This will get better in 95% of patients within 4-6 weeks, and in 99% within a year.
Questions you may like to ask your anaesthetist
- Who will carry out my injection?
- Will someone stay with me during my operation?
- Do I have to be awake?
- What happens if I can feel something?
- When will my foot start to feel normal again?
- Who should I call if I am worried about the effects of the block after surgery?
If you have any issues or concerns, about your anaesthetic, after your operation please contact:
Anaesthetic Department: 0117 414 5114, Mon-Fri, 9am to 5pm
For pain that is not controlled by your tablets, please go to the Emergency Department.