Salivary gland injections with botulinum toxin

Botulinum toxin is produced naturally by the bacterium clostridium botulinum. When purified, it can be used in tiny, controlled doses to relax excessive muscle contraction. It has been used as a medicine in the UK since the 1990s.

These are injections into the salivary glands, which are intended to reduce saliva production. This should reduce how much your child dribbles and drools. Dribbling and drooling can be a problem with various neuromuscular diseases, such as cerebral palsy.

The botulinum toxin acts on the nerves around the salivary glands reducing the amount of saliva produced.

The injections are carried out in the Interventional Radiology (IR) department by a specialist who uses imaging to carry out procedures.

You will already have received information about how to prepare your child for the procedure in your admission letter. You may need to come to GOSH before the procedure so that your child can have a pre-admission assessment to check that they are well enough. The appointment may involve taking blood samples and other tests.

Your child will need to be admitted to a bed on a ward in the hospital. The person bringing your child to the procedure should have ‘parental responsibility’ for them. Parental responsibility refers to the individual who has legal rights, responsibilities, duties, power and authority to make decisions for a child. If the person bringing your child does not have parental responsibility, we may have to cancel the procedure.

An anaesthetist will visit to talk to you about your child’s anaesthetic. The specialist performing the procedure will explain the procedure in more detail, discuss any questions you may have and ask you to sign a consent form giving permission for your child to have the procedure. If your child has any medical problems, please tell the specialists.

Many of the procedures we perform involve the use of x-rays. Legally, we are obliged to ask anyone over the age of 12 whether there is any chance they might be pregnant, and we will also ask for the first date of their last period (if started). This is to protect babies in the womb from receiving unnecessary radiation.

You and your child will then be brought to the IR suite within the X-ray department for the procedure to be done.

You will already have received information about how to prepare your child for the procedure in your admission letter. You may need to come to GOSH before the procedure so that your child can have a pre-admission assessment to check that they are well enough. This appointment may involve taking blood samples and other tests.

Your child needs to be fasted for the procedure for the general anaesthetic. If your child takes regular medication, please speak to your child’s team about when to stop these before the procedure.

As a general rule:

Food and milk:

• Breast-fed babies- can have their last feed three hours before the procedure. Breast milk is digested faster than solid food or formula.
• Bottle-fed babies and children- can have their last milk feed, food or milk drink, six hours before the procedure. They should not have any food or milk after this time.

Water:

• All babies and children can have a drink of water (but no other fluids), until one hour before the procedure.

It is equally important to keep giving your child food and drink until those times to ensure they remain well-hydrated and get adequate nutrition. This may involve waking your child in the night to give them a drink which we recommend.

Please follow these instructions carefully, otherwise your child’s procedure may be delayed or even cancelled.

When your child is under general anaesthetic, the radiologist will use ultrasound to identify the exact position of your child’s salivary glands.

The salivary glands lie along the jaw line. They will then insert a small needle through the skin into the glands, again using ultrasound to guide them. They will then inject the botulinum toxin into the gland.

Once enough botulinum toxin has been infused, they will remove the needle. No dressing is needed as there is only a tiny puncture in the skin.

The injection procedure lasts about 30 minutes.

Your child will be having the procedure under general anaesthetic. Every anaesthetic carries a risk, but this is extremely small.

There is a very small chance that the nerves and muscles around the salivary glands could be affected by the botulinum toxin, which could cause chewing and swallowing difficulties and aspiration (saliva or fluid into the lungs) of food and drink. Using ultrasound to identify the exact position of the glands reduces the chance of this happening. If this does happen, an NG tube may need to be placed and the patient fed through this until the swallowing problems clear up. This may require a longer hospital stay. The effects of the botulinum toxin usually lasts up to six months.

Salivary gland injections with botulinum toxin are not a permanent solution to excessive dribbling and drooling and they are not effective for every child.

If they are effective, you should notice a reduction in your child’s dribbling and drooling between three and eight days after the injections. It may take longer for positive effects to show in some children, occasionally taking two to four weeks. Some children may only show partial effects. The effects of the injections last between three and six months so the procedure may need to be repeated in future.

The procedure may involve the use of X-rays. The levels that are used are low dose and therefore low risk. If you have any concerns regarding the use of radiation, please discuss this with the person performing your procedure beforehand.

Medicines can be used to ‘dry up’ your child’s saliva but it can be difficult to achieve a good balance between drying your child up too much and not giving an adequate dose.

Surgery to re-position the salivary gland duct (opening into the mouth) to the back of the mouth is also possible.

This procedure is called a bilateral submandibular duct transposition (BSMDT). Some patient’s glands are removed surgically.

Your child will return to the ward after they have recovered from the general anaesthetic. Some children feel sick and vomit after a general anaesthetic.

Your child may have a headache or sore throat or feel dizzy, but these side effects are usually short-lived and not severe.

Your child can start eating and drinking as normal once they feel like it.

An operator – usually the specialist that performed the procedure – from IR will assess your child’s swallowing before you can leave.

Your child may experience pain or discomfort around the injection site. This should only last for a couple of days and paracetamol is usually enough to make your child feel more comfortable.

Some children complain of mild flu-like symptoms in the days after injections, which may be treated with paracetamol if necessary.

Usually, your child should feel well enough to return to school the day after the injections.

You should call the hospital (or go to A&E out of hours) if:

• The injection site looks red, swollen and feels hotter than the surrounding skin.
• The injection site is oozing.
• Your child is in a lot of pain and pain relief does not seem to help.
• Your child has difficulty swallowing or chewing.
• Your child has a temperature of 38⁰C or higher.

You can call the ward by calling the GOSH switchboard and asking for the ward your child was discharged from.

Telephone: 020 7405 9200

If you are unable to get through, please call NHS111 by dialling 111.

If you have any questions, please speak to you child’s doctor or nurse or call Interventional Radiology:

Telephone: 020 7405 9200

You can also contact us through MyGOSH.