Having a Local Anaesthetic and/or Sedation

This information sheet is for people having a local anaesthetic and/or sedation. This information can be used in conjunction with further information about the operation which you are about to undergo.

What is a local anaesthetic?

A local anaesthetic (or LA) is a type of medicine which has the effect of numbing the area in question. In so doing it is possible to perform an operation whilst the patient is awake without any feelings of pain or discomfort. The medicine is usually injected into and around the area where the surgery is to occur, although alternative methods of administering the LA include by a spray (for example, if the operation is within the nose or mouth) or topical cream.

What is sedation?

Sedation refers to the use of a drug which has the effect of relieving anxiety, causing relaxation and inducing a degree of lethargy without actually putting you to sleep. Sedation is often used in conjunction with a local anaesthetic, and allows a more extensive surgical procedure to take place than is possible with a LA alone. In many cases, the combination of a LA and sedation will mean that a general anaesthetic is not required.

Sedative drugs can be injected through an intravenous cannula, inhaled as a mixture of gas and air, or swallowed in tablet or liquid form.

Preparing for the anaesthetic and operation

You will already have had a discussion with your surgeon about having the operation, and you may have attended a preadmission clinic appointment either by telephone or in person at which your other medical conditions and general overall fitness will have been assessed.

Please see separate information sheet ‘Preparing for your operation’ for further information.

On the day of the operation

Have a bath or shower at home on the day of the operation, taking care to remove any jewellery and make-up particularly if within the area to be operated on. For sensitive items of jewellery such as a wedding ring which you may not want to remove, these can be covered with sticky tape. Also remove any hearing aids, glasses and contact lenses just prior to going to the theatre.


Fasting is not essential prior to a LA although it is not advisable to eat a heavy meal within 2 hours of the procedure as this may make you feel sick. This is particularly the case if you are likely to receive sedation. In some cases, surgeons request that you do fast for 6 hours before the operation as if a general anaesthetic were to be used in case it is necessary to alter the anaesthetic plan at short notice. Make sure you follow the fasting instructions given to you at the preadmission appointment.

Preparation for the local anaesthetic/sedation

Very little preparation is usually required before the procedure.

How is local anaesthetic given?

Local anaesthetic drugs can be given either by injection into the local area, by means of a spray, or rubbed in to the site in gel form. The area concerned will begin to feel numb quite quickly. The surgeon will check that the local anaesthetic has taken effect, and only then will the operation start. It is quite normal to still be able to feel movements and pressure during the procedure, as long as you do not experience any discomfort. If you do, mention it to your surgeon or theatre nurse as a top-up of anaesthetic may be required.

If sedation is given, the oxygen level in your bloodstream will be monitored closely through a small device attached to your fingertip, your blood pressure will be periodically taken, and extra oxygen may be given to you through a face mask.

After the anaesthetic

Once the operation has finished, you will be transferred back to your room on the ward. You will be able to make arrangements to go home soon after this, as soon as any prescribed medications have been given to you. The effects of sedation can take a few hours to wear off completely, so you may be asked to remain in hospital for s short period of monitoring. Ensure that you look after the operated area as it may be numb to touch for several hours, and take any painkillers or other medications as directed by your surgeon.

If you have received sedation, do not drink alcohol, operate machinery or sign legal documents for 48 hours following the procedure, as the effects can persist for some time in certain individuals.

What are the risks?

Local anaesthesia and sedation are commonly performed and generally extremely safe. However, as with all medical procedures and interventions, there is a small degree of risk involved which needs to be balanced carefully against the benefit to be gained from the operation.

During or shortly after the procedure there may be a temporary modest drop in blood pressure which may make you feel light headed or faint. Sometimes you may experience a tingling or pins-and-needles sensation around the lips and mouth, which can indicate that some of the local anaesthetic has entered your blood stream. Your anaesthetist may want to monitor your heart rate for a little longer if this occurs. There is also a very small but definite risk of experiencing an adverse reaction to the local anaesthetic agent, as is the case with taking any medication.