Microlaryngoscopy and bronchoscopy (MLB)

This page explains about a microlaryngoscopy and bronchoscopy (MLB) and what to expect when your child comes to Great Ormond Street Hospital (GOSH) to have this procedure.

What is a microlaryngoscopy and bronchoscopy (MLB)?

Chest - internal

A microlaryngoscopy and bronchoscopy is a test that allows the doctor to look into your child’s airway (larynx and bronchi) using a small telescope. This telescope is contained in a piece of equipment called an endoscope.

Why does my child need this investigation?

In general, it is because your child has breathing problems and an MLB will help the medical team to establish a cause.

What happens before the MLB?

Information about how to prepare your child for the operation is included in your admission letter. Your child should not have anything to eat or drink for the time discussed at the pre-operative assessment. It is important to follow these instructions otherwise your child’s operation may have to be delayed or even cancelled.

The doctors will explain the operation in more detail, discuss any worries you may have and ask you to sign a consent form. An anaesthetist will also visit you to explain about the anaesthetic. If your child has any medical problems such as allergies, please tell the doctors.

About half an hour before your child goes to operating theatre, he or she may have a pre-medication. This is a medicine which dries up any secretions, allowing the anaesthetist to see your child’s airway more clearly. It may be given as an injection or as a liquid medicine to drink.

What does the investigation involve?

Your child will have this procedure under a general anaesthetic. Please see your admission leaflet for more information about anaesthetics.

After the general anaesthetic has been given, your child’s larynx will be sprayed with a local anaesthetic. The surgeon will then insert the telescope into your child’s airway through the mouth. The doctor can now look at your child’s larynx and bronchi.

Will the doctor do anything else?

In some cases the doctor will also ask for your permission to carry out surgical procedures using a laser or endoscopic instruments at the time of the MLB. No procedure will be carried out without your consent (unless in a rare emergency situation).

What are the risks of an MLB?

Every anaesthetic carries a risk of complications, but this is small. Your child’s anaesthetist is an experienced doctor who is trained to deal with any problems that arise. After an anaesthetic some children may feel sick and vomit. They may also have a headache, sore throat or feel dizzy. These side effects are usually short-lived and not severe.

There is a very small risk that the telescope could damage your child’s airway. Your child's breathing problems may worsen after the procedure but this is temporary.

Are there any alternatives to having a MLB?

Although the doctors can tell a certain amount from other tests, an MLB can give them a fuller picture of your child’s condition.

What happens after the MLB?

Your child will be able to recover from the investigation on the ward. He or she may have a sore throat after the test and the doctors may prescribe some paracetamol. The doctors will see you later the same day to tell you what they found during the investigation.

Your child will not be able to eat or drink anything for three hours after the procedure.

Your child will be able to go home the next day.

Because of the anaesthetic your child may feel tired and a little clumsy for around 24 hours after the operation, so do not let him or her do anything that may lead to a fall.

You will be sent the date for a follow-up appointment either in the outpatients department or to come back to the hospital for another stay. Your child should be able to go back to school when he or she is more comfortable.

If your child develops a fever, contact your family doctor (GP) or the ward from which your child was discharged.

Last reviewed by Great Ormond Street Hospital: January 2013

Compiled by:
Peter Pan ward in collaboration with the Child and Family Information Group.
Last review date:
April 2016