If your child has been invited for a face-to-face appointment or procedure, it’s important you still come unless you hear otherwise.
To help keep everyone safe, only one parent or carer can attend. No other family or friends can visit.
See all our information about COVID-19, including steps we are taking to keep you safe.

Your child's general anaesthetic

Do you have questions about your child having a general anaesthetic? This page explains the role of the anaesthetist, and the possible side effects and complications that can happen.

What is a general anaesthetic?

General anaesthetic is medicine that is used to make sure a person is asleep and does not feel any pain during an operation. Specially trained doctors, called anaesthetists, care for all patients having a general anaesthetic.

All children having an operation will be cared for by specialised paediatric (children’s) anaesthetists who have been specifically trained to give general anaesthetics to children. These doctors stay with your child during their operation or procedure and wake them up once it is over.

Before the operation

The anaesthetist will meet you and your child before the operation – this may be on the day of the operation or at an outpatient appointment. This meeting is sometimes called a “preoperative assessment”. The anaesthetist will talk with you about which anaesthetic technique is most suitable for your child and what kind of pain relief your child will get after their operation.

Please do not hesitate to ask questions if you have any particular concerns or if you are uncertain about anything. You will be asked about your child’s medical history, including:

  • whether he/she has had a general anaesthetic before
  • what medicines your child is taking
  • whether your child has any allergies
  • if your child has any loose teeth.

For practical reasons, the anaesthetist who meets you before the operation may not always be the one who gives your child their anaesthetic. However, please rest assured that the information you give them will be passed on to the anaesthetist looking after your child on the day of their operation or procedure. Occasionally, the anaesthetist may decide to delay your child’s operation if he/she feels that it would be safer for your child to do so. This could happen if your child has a bad cold, a rash or has eaten food too recently. 2 of 6 Asking for consent (permission) Discussing your child’s treatment with you is part of our consent process. We want to involve you and your child in all the decisions about your child’s care and treatment. Further information about giving permission for your child’s treatment is available in the Trust’s leaflet Consent to treatment for your child. You will have been sent one of these with your child’s appointment letter, but if you would like a copy please ask.

Preparing your child

Your child should not have any food for six hours before the operation. This is to make sure his/her stomach is empty. If food is in the stomach while having a general anaesthetic, your child is at a higher risk of being sick while unconscious – this could lead to serious complications.

Your child can drink water up until two hours before the operation. Please carefully follow the instructions you are given on your admissions letter about when your child can last eat or drink.

Breastfed babies: You can breastfeed your baby up to four hours before the operation.

Babies having bottle-milk: You can give your baby bottle-milk up to six hours before the operation (as for food). 

Whilst on the ward a nurse may put some local anaesthetic cream on your child’s hands about one hour before the operation. It is sometimes called ’magic cream’ because it stops your child feeling any sharp pain when the anaesthetist puts a cannula (small plastic tube) into a vein. The cannula allows the anaesthetist to give the general anaesthetic as well as any other necessary medicines.

Anaesthetists usually prefer to give the general anaesthetic through the cannula when possible. However, sometimes they give the anaesthetic through a face mask, which means your child may not need the local anaesthetic cream. The anaesthetist will speak to you about this in more detail.

Can I be with my child while he/she is having the anaesthetic?

You will be able to go with your child to the anaesthetic room, which is next to the operating theatre. There, you will meet a member of theatre staff who will check your child’s details and help the anaesthetist. Sticky pads will be placed on your child’s chest to monitor their heart. A rubber peg will be put on his/her finger to monitor oxygen levels. Your child will fall asleep within a couple of minutes of having the general anaesthetic. The nurse will then take you back to the ward.

What are the side effects and complications with having an anaesthetic?

Modern anaesthesia is very safe and serious problems are uncommon. Most children recover quickly and are soon back to normal after an anaesthetic. The anaesthetist will use specialist equipment to monitor your child closely throughout their operation. However, all risk cannot be removed completely and some children may have side effects or complications. Side effects are secondary effects of medicines or treatment. They can often be expected but are sometimes unavoidable. Some examples are having a sore throat or feeling sick after the operation.

Side effects usually last only a short time and can be treated with medicines if needed. Complications are unexpected and unwanted events due to a treatment. Some examples are damage to teeth or an unexpected allergy to a medicine. The exact likelihood of complications depends on your child’s medical condition, the type of surgery and anaesthetic used. If there are risk factors specific to your child, these will be discussed with you before the operation.

This scale below is used to help you understand how likely your child is to have a side effect or complication related to anaesthesia:

A scale to help you understand how likely your child is to have a side effect or complication related to anaesthesia.

Very common (1 in 10 – 1 in 100)

Nausea and vomiting, headache, drowsiness, dizziness, blurred vision

These may be due to the effects of medicines we use, to the surgery or to lack of fluids. They usually get better within a few hours and fluids or medicines can be given to treat these problems.

Sore throat

If a tube is placed in the airway to help your child breathe during the operation, he/she may get a sore throat. This is usually only mild and will often settle without treatment.


This may occur because your child gets cold during the surgery, because of the medicines used, or it may be due to anxiety. Your child can be warmed very efficiently using a hot-air blanket.


This is a side effect of opiate medicines (such as morphine) and can be treated with other medicines.

Bruising and soreness

This can happen around injection and drip sites. It normally settles without treatment, but if the area becomes uncomfortable, the position of the drip can be changed.

Difficulty in passing urine

This may occur if your child has had an injection in the spine (a caudal or epidural) for pain relief. A urinary catheter may be inserted until the caudal/epidural wears off.

Uncommon (1 in 1,000)

Damage to teeth, lips, gums or tongue

Damage may be caused when the breathing tube is put in or taken out, or by teeth clenching during recovery from the anaesthetic.

Breathing problems

Shallow or slow breathing may occur if some of the anaesthetic medicines are still having an effect, or as a result of some pain-relieving medicines. These effects can be reversed with other medicines.

Behavioural problems

Some anaesthetic medicine can cause children to become agitated as they recover from anaesthesia. This will resolve as the medicine wears off. Muscle pains These may occur as a side effect of one of the anaesthetic medicines and can be treated with simple pain-relieving medicine, such as paracetamol (Calpol®).

Rare to very rare (1 in 10,000 – 1 in 100,000)

Damage to eyes

We take great care to protect your child’s eyes but sometimes the surface of the eye becomes damaged from contact, pressure or exposure of the cornea. This is usually temporary and treated with eye drops.

Serious allergy to drugs (anaphylaxis)

Allergic reactions will be noticed and treated very quickly. Very rarely, these reactions can be very serious, and may lead to death even in healthy children.

Stomach contents getting into the lungs (aspiration)

This can occur if there is still food or drink in the stomach before anaesthesia. This may cause a severe and sometimes life-threatening pneumonia (lung infection).


Becoming conscious during the operation is rare in children. Monitors will be used to record how much anaesthetic is in the body and how the body is responding to it. These help the anaesthetist to make sure your child has enough anaesthetic to keep him/her unconscious during the operation.

Nerve damage

Nerve damage may be caused by pressure on a nerve during an operation, or it may occur as a complication of a regional block (peripheral nerve block, caudal or epidural). Nerve damage from regional blocks may be due to direct injury from the needle or catheter, injury to blood vessels near a nerve which causes pressure from a blood clot, or due to infection. Anaesthetists are trained to be aware of nerve damage and take steps to prevent it. If it does occur it may cause numbness, ‘pins and needles’, muscle weakness or paralysis. However, these are usually temporary and most patients make a full recovery after a few days or weeks. Permanent damage is very rare. 

Equipment failure

Equipment is tested regularly and monitors are used which give an immediate warning of any problems. Equipment failures rarely have serious effects.

Brain damage and death

Brain damage and deaths caused by anaesthesia are very rare and are usually caused by a combination of complications arising together. Throughout the whole of life, an individual is at least 100 times more likely to suffer serious injury or death in a road traffic accident than as a result of anaesthesia. There are only about five deaths for every million anaesthetics given to children and adults in the UK.

What happens after the operation?

Your child will be taken to the recovery room (near the operating theatre) as soon as the operation is finished. Here, specially trained recovery nurses will closely monitor your child. You will be taken to the recovery room as soon as your child starts to wake up. When your child is ready, the ward nurse and a porter will take your child back to the ward with you. Your child may be able to start drinking fluids and then have a light diet within a few hours of getting back to the ward – this will depend on the type of operation. Please speak to your child’s nurse before giving your child any drinks or food.

Contact us

If you have any questions or concerns about your child having an anaesthetic, please speak to the nurse at the pre-operative assessment who can contact the anaesthetist for you.

Leaflet number: 2097/VER5
Date published: January 2017
Review date: January 2020
© 2017 Guy’s and St Thomas’ NHS Foundation Trust

Printable PDF

Download Your child's general anaesthetic (PDF 100Kb)

Was this helpful?

If you have any comments about this information, we would be happy to hear from you. Fill in our simple online form or email:


Our information is changing

Find out how we are making our patient information more accessible and inclusive.

Evelina London Medicines Helpline

If you have any questions or concerns please contact

If you have any questions or concerns about your child’s medicines, please speak to the staff caring for them or contact our helpline.

Tel: 020 7188 3003 
(Monday to Friday, 10am-5pm)

Email: letstalkmedicines@

©  Guy's and St Thomas' NHS Foundation Trust.
King's Health Partners logo