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This leaflet gives basic information to help you prepare for you anaesthetic. Other leaflets available are:

  • Interscalene brachial plexus block for shoulder surgery

  • Brachial plexus block for elbow, wrist and hand

  • Looking after your arm and hand after a block

Anaesthesia Anaesthesia allows you to have surgery or a procedure without feeling pain.

Local anaesthesia involves injections which numb a small part of your body. You stay awake and although you may feel something, it should not hurt.

Regional anaesthesia involves an injection which numbs a larger part of the body, for example your arm or your legs. You can stay awake or have some sedation. Although you may feel something, it should not hurt. You need to follows the starvation instructions for this.

General anaesthesia is when drugs are used to make you unconscious or ‘send you to sleep’ so you will not be aware of anything. You need to follow the starvation instructions for this.

Before coming to hospital Here are some things that you can do to prepare yourself for your operation:

  1. If you smoke, giving up for several weeks before the operation reduces the risk of breathing problems and makes your anaesthetic safer. The longer you can give up beforehand, the better. If you cannot stop smoking completely, cutting down will help.

  2. If you are overweight, reducing your weight will reduce many of the risks of having anaesthetic.

  3. If you have loose teeth or crowns, treatment from your dentist may reduce the risk of damage to your teeth if the anaesthetist needs to send you to sleep.

Anaesthetists Anaesthetists are doctors with specialist training who:

  • assess your health and fitness for an anaesthetic

  • discuss types of anaesthesia with you

  • agree a plan with you for your anaesthetic and pain control

  • are responsible for giving your anaesthetic and for your wellbeing and safety throughout your surgery

  • make your experience as calm and pain free as possible.

Your Health If you have a long-standing medical problem such as diabetes, asthma, bronchitis, thyroid problems, heart problems or high blood pressure (hypertension), you should ask your GP if you need a check up

  • If you develop a cold or infection of any kind, you should let the hospital know as soon as possible as it may be safer to postpone your operation until you are well again.

Pre-assessment You need to be asked some questions to check your health before your operation. This will usually be by a nurse. You may be asked to fill out a questionnaire. It is important for you to list:

  • all the pills, medicines, herbal remedies or supplements you are taking, both prescribed and those that you have purchased over the counter.

  • any allergies you may have.

If you have a significant health problem that needs investigating or can be improved by further treatment before surgery, your surgery may be postponed in order for this to happen. This is done for your safety and it will be explained why and what will happen next.


Before you arrive:

  • Nothing to eat or drink (fasting ‘Nil by mouth’)

It is important to fast before an anaesthetic. If there is food or liquid in your stomach during your anaesthetic it could come up to the back of the throat and damage your lungs. You must starve before any regional or general anaesthetic.

You must have nothing to eat This includes food, milk, sweets, chewing gum and fizzy drinks


2:00am if your operation is in the morning

7:00am if your operation is in the afternoon

11:00amif your operation is in the evening

You may drink water or dilute squash until:

6:00am if your operation is in the morning

11:00am if your operation is in the afternoon

3:00pm if your operation is in the evening



If you are taking medicines you should continue to take them as usual, unless the Pre-operative nurse, anaesthetist or surgeon has asked you not to. You may have a sip of water if necessary. If you take drugs to stop you getting blood clots (anti-coagulants), or drugs for diabetes you will need specific instructions.

You should remove all nail varnish, false nails, tongue and nose studs.

If you feel unwell when you are due to come into hospital, please telephone the place you are due to be admitted for advice.


When you arrive in hospital Your anaesthetist will meet you before your operation to:

  • ask you about your health

  • discuss with you which types of anaesthetic can be used

  • discuss with you the benefits, risks and your preferences

The choice of anaesthetic depends on:

  • your operation

  • your answers to the questions you have been asked

  • your physical condition

  • your preferences and the reasons for them

  • your anaesthetist’s recommendations for you and the reasons for them

  • the equipment, staff and the other resources available at the hospital

Premedication (a ‘premed’) is the name for drugs which are given before some anaesthetics. Some premeds prepare your body for the anaesthetic, others help you to relax. They may make you more drowsy after the operation. If you want to go home on the same day, this may be delayed by a sedative type of premed. If you think a premed would help you, ask your anaesthetist. If you having a local or regional anaesthetic, you will also need to decide whether you would prefer to:

  • be awake

  • be relaxed and sleepy (sedation)

  • have a general anaesthetic as well

Sedation is the use of small amounts of drugs to produce a ‘sleepy-like’ state. You need to be starved to be able to have any sedation.

The Operating Department (theatres) Your anaesthetic may start in the anaesthetic room or in the operating theatre. The anaesthetic team will attach you to a monitor which measures your heart rate, blood pressure and oxygen levels. Your temperature will also be checked. A cannula (a thin plastic tube) will be inserted into a vein in the back of your hand or arm.

Local and Regional Anaesthetics

  • Your anaesthetist or surgeon will ask you to keep quite still while the injections are given

  • You may notice a warm tingling feeling as the anaesthetic begins to take effect

  • Your operation will only go ahead when you and the anaesthetist or surgeon are sure that the area is numb

  • If you are not having sedation you will remain alert and aware of your surroundings. A screen shields the operating site, so you will not see the operation

  • Your anaesthetist is always near to you and you can speak to him or her whenever you want to

  • For cases under local anaesthetic only, the surgeon will give you the local anaesthetic and look after you

General Anaesthetics There are two ways of starting a general anaesthetic:

  • Anaesthetic drugs may be injected into a vein through the cannula (this is used for most adults and children)

  • You can breathe anaesthetic gases and oxygen through a mask, which may hold if you prefer (occasionally administered to children)

Once you are unconscious, an anaesthetist stays with you at all times and continues to give you drugs to keep you asleep. As soon as the operation is finished the drugs will be stopped to allow you to wake up.


You will be taken to the recovery room. If you have had a general anaesthetic this is where you may first wake up. Recovery staff will be monitoring you at all times. When they are satisfied that you have recovered safely from you anaesthetic you will be taken back to the ward.

Pain Relief Good pain relief is important and some people need more pain relief than others. It is much easier to relieve pain if it is dealt with before it gets bad. Pain relief can be increased, given more often, or given in different combinations. Occasionally, pain is a warning sign that all is not well, so you should ask for help when you feel pain.

What will I feel like afterwards? How you feel will depend on the type of anaesthetic and operation you have had, how much pain relieving medicine you need and your general health.

Understanding Risk In modern anaesthesia serious problems are uncommon. Risk cannot be removed completely, but modern equipment, training and drugs have made it a much safer procedure in recent years.

To understand a risk, you must know:

  • how likely it is to happen

  • how serious it could be

  • how it can be treated

The risk to you as an individual will depend on:

  • whether you have any other illness

  • personal factors such as smoking or being overweight

  • whether your surgery is complicated

  • whether your operation is an emergency

More information about risks associated with having an anaesthetic can be found on:

People vary in how they interpret words and numbers This scale is provided to help: Very Common 1 in 10 Common 1 in 100 Uncommon 1 in 1000 Rare 1 in 10,000 Very rare 1 in 100,000

Side effects and complications More information on the side effects and complications can be found in the booklet ‘Anaesthesia explained’.

Very common and common side effects

Side effect

Regional anaesthetic

General Anaesthetic

Feeling sick and vomiting after surgery



Sore throat


Dizziness blurred vision






Bladder problems



Damage to lips or tongue (usually minor)