A Patient's guide to Your Child’s General Anaesthetic for a Scan

MRI stands for Magnetic Resonance Imagining. It uses a magnetic field to take detailed pictures of the body. The MRI scanner is a hollow, tunnel shaped machine. There is a bed in the middle that your child will lie on, that slides in and out.

CT stands for Computed Tomography and uses X-rays to take detailed pictures of the body. The CT scanner is a doughnut shaped machine that also has a bed in the middle that slides in and out.

Your child’s doctor will need this scan to show detailed pictures of the body.

The type of scan used depends on the reason for the scan. Other scans such as ultrasound and X-rays may not show the detail that is needed to help with diagnosis and treatment.

A biopsy is a procedure where a small amount of body tissue is taken with a special needle, and looked at under a microscope. This helps the doctors diagnose medical problems.

Only a small amount of tissue is taken. If your child needs a biopsy, it is likely that they will have an anaesthetic and painkillers can be given. The site of the biopsy will be covered by Steristrips (butterfly stitches) and a small dressing.

There are no risks associated with MRI scanning. CT scans use a dose of radiation. CT scans are only done when the benefit of the scan outweighs the risk. The dose of radiation is always kept as low as possible. Both MRI and CT scans are not painful, but your child may need an anaesthetic for the scan and the risks of this part are discussed below.

• Having a scan involves your child lying very still on a moving table, which carries them inside the scanner. Some children may find being  in the scanner frightening. MRI scanners, in particular, are quite noisy. While some scans last only a few minutes, others take over an hour,  and children may find it impossible to lie perfectly still for that long. Sometimes your child will need to hold his/her breath for a few seconds.
• Some children (and most adults) have scans done while awake. Scans are not painful. If your child is having an MRI awake, you can stay with them and are welcome to bring in a CD for them to listen to during the scan. Even quite young children can lie still for their scans, as long as they know what to expect. Nurses and play therapists can be very helpful in preparing a child for this. The play therapists have developed a replica toy MRI scanner with realistic sounds and movements. This can show your child what happens during a real scan and can encourage them to have a scan awake. Further information about this replica and the play preparation programme please contact the play therapy team (see contacts section).
• However, the doctor arranging your child’s scan might think that trying to do it awake wouldn’t work, and ask for it to be done under a general anaesthetic. If your child is having a biopsy it is likely they will need to have an anaesthetic.

General anaesthesia is a state of controlled unconsciousness. Anaesthetics are the drugs (gases and injections) that are used to provide anaesthesia.
 

Anaesthetics are only given by anaesthetists in the UK. They are specialist doctors who have trained specifically to care for patients under anaesthesia.

An anaesthetist will monitor your child at all times during the anaesthetic and all anaesthetics for children are overseen by a consultant anaesthetist.

An anaesthetist will visit you on the ward before the procedure to discuss your child’s anaesthetic. This is a good time to talk about any previous experiences your child has had with injections or hospitals, or any particular concerns you have about this hospital visit. For practical reasons, the anaesthetist who comes to see you on the ward may not always be the same one who gives your child’s anaesthetic, but the information you give them will be passed on.

• Most children come from home to have their scan, and can go home again afterwards.
• There are things that you can do to prepare your child for coming into hospital. You should try and explain to your child (except infants too young to understand) that they are going into hospital, that they will be having a scan, and some basic information about what will happen to them when they are in hospital. Please let us know in advance any special requirements your child has and we will do whatever we can to help.

Please phone the hospital if your child develops a cough or cold, or diarrhoea or vomiting, or has been in contact with chicken pox shortly before the day of the scan.

You will be sent a letter giving information about fasting. It is important for your child to follow these instructions. If there is food or liquid in your child’s stomach during the anaesthetic, it could come up into the back of the throat and damage his or her lungs.

If your child is coming into hospital on the same day as the scan, please follow these instructions:

• Do not give any food, formula, or milk containing products after 2am on the day of the scan
• Do not give any breast milk after 4 am on the day of the scan
• Encourage your child to have a drink of water or dilute squash before 6am
• Do not give any water or dilute squash after 6 am on the day of the scan

If you are unsure what you can or cannot give, please contact the Paediatric Pre-Admission Department or Children’s Ward, on the numbers given below.

Planned scans are done during a session which lasts a day. The letter you will be sent should be clear about the time your child should start fasting.

However, the exact time of the scan may change on the day and is sometimes earlier than planned. If your child has to wait more than 2 hours for the scan, the ward staff may offer him or her some more water/squash to drink.

Your child can either have:

• An injection through a cannula- a thin plastic tube placed, using a needle, into a vein on the back of the hand, the arm, or occasionally the foot. The needle is removed once the cannula is in place. If a cannula is planned, anaesthetic cream is usually put on in advance to make the skin numb and make the needle puncture less painful.The cream takes at least half an hour to work, so please do not remove it.
• or anaesthetic gas to breathe, through a small face mask. A cannula is then put in while your child is asleep.The anaesthetist will discuss these options with you and your child, so that you have an agreed plan before the anaesthetic starts.

The anaesthetic is started in the anaesthetic room which is next to the scanner. We encourage a parent or guardian to be with the child at the start. For smaller children, the anaesthetic may be started with your child on your lap. As soon as your child becomes unconscious, he or she is lifted onto the anaesthetic trolley, and we ask you to leave and return to the ward.

Your child is transferred to the scan room, and then at the end, to the recovery cubicle where he or she will wake up. Some children wake very quickly; while for others, recovery from the anaesthetic takes longer. Your child will usually be conscious within about fifteen minutes of the end of the scan, and we will call you through to the recovery area as he or she is waking up

Many children are a bit confused and tearful when they first wake up after an anaesthetic. It is common for children to feel dizzy for a few hours afterwards. Most children can have fluids to drink as soon as they feel like it and then food a bit later.

The ward nurses will advise you, but in general, most children should be ready to go home about two hours after getting back to the ward.

How safe is general anaesthesia for scans, and what are the risks?

• With modern anaesthesia, serious problems are uncommon. However, there is always some risk with any medical procedure, including anaesthesia.
• Modern equipment, training and drugs have all improved the safety of anaesthesia in recent years. We take a great many safety precautions in every case, to try to make the risks as small as possible.
• Estimating these risks for your child’s particular case is very difficult.The figures given below apply to children with no major health problems. The likelihood of a serious risk or complication is higher if your child has a serious illness, or is under the age of 1.

The common risks

These are generally minor side effects of anaesthesia, and almost always get better quickly, and without any treatment at all.

• 1 child in 10 experiences a headache or a sore throat
• 1 child in 10 experiences sickness or dizziness. Anti-sickness medication will be available to help if necessary.
• 1 child in 5 becomes agitated on waking

Allergic reactions

 Around 1 child in 10,000 develop a serious allergic reaction to the
 anaesthetic.

Rare risks

•  A few cases of serious problems as a result of anaesthesia in children are reported every year in the UK. Some of these occur during anaesthesia for minor procedures such as scans.
• The causes can vary widely, but include serious breathing problems, serious allergic drug reactions, major equipment failure, and accidents. Because these problems are so infrequent, it is very hard to give accurate figures for how often they occur.
• Even serious incidents are often successfully dealt with, without permanent harm coming to the patient. However, rarely, the end results can be catastrophic, and include death and permanent brain damage.
• The risk of death from anaesthesia for healthy children having minor or moderate non-emergency surgery is less than 1 in 100,000, which about the same risk as being killed as a pedestrian in a road traffic accident in the next year.

My child has special medical problems, or is suspected to have a serious health problem. Are there any extra risks with the anaesthetic?

• The risk for your child will be higher than those figures quoted previously. Some children have very complex or rare health problems, which may not even be known about at the time they have their first ever anaesthetic. Indeed, some are having scans to try to diagnose such serious problems.
• The conditions which worry anaesthetists most are severe heart or breathing disorders, and a few rare genetic conditions. Children with these problems may need to be observed in hospital after having an  
• anaesthetic for any reason.
• Your anaesthetist will be happy to discuss the particular risks in your child’s case. Sometimes the doctor arranging the scan will discuss your child’s case with the anaesthetist beforehand, so that special arrangements can be made.

Occasionally the anaesthetist may learn something about your child that means it would be safer not to do the procedure on that day.

If something important has changed about your child’s condition since the scan was planned with your doctor: please get in touch with the doctor who arranged the scan. The scan might no longer be necessary, might need to be done more urgently, or a different test altogether might now be necessary.

• The medical team arranging the scan will ask you to sign a consent  form to indicate your agreement for the scan. By signing the form, you are saying that you understand the reason for the scan. The anaesthetist will talk to you about the anaesthetic.
• In most cases, the scan will be looking for important information for  your child’s care: either to make or rule out an important diagnosis, or to direct his/her treatment. If having an anaesthetic is the only way to get that information, then it may well be worth taking these risks.
• However, if you have any doubts or further questions about the scan, the reason it is being done or the need for an anaesthetic, you are welcome to discuss it further with your doctor and anaesthetist before deciding whether or not to go ahead.

The medical staff and organisations listed below will be happy to be contacted if you have any unanswered questions or concerns.

Paediatric Pre-Admission Department
020 8909 5630

Play Therapy Department – via switchboard
020 3947 0100
Ask to bleep Play Therapist

Radiology Department – Scanning
020 8909 5801

Sir William Coxen Ward (Children’s Ward)
020 8909 5487

Patient Advice and Liaison Service (PALS)
020 8909 5439
Email: rnoh.pals@nhs.net

Further information for children and their carers can be found on the Royal College of Anaesthetists website. This includes age appropriate information leaflets and some short videos.

Additional information can be found at Association of Paediatric Anaesthetists of Great Britain and Ireland.

Thanks to Dr Philip Segar and Dr Adrian Upex at Bristol Children’s Hospital.