What is a shunt revision?
If your child has a shunt in place, it may stop working properly. A shunt that is not working properly will need a part or all of it replaced. Doctors call this surgical procedure a revision.
When a shunt is not working properly, it is because of one of the following reasons:
- Particles or tissue may enter the shunt and block the flow of cerebral spinal fluid (CSF).
- The shunt may become disconnected or broken, so that the CSF no longer drains into the right place.
- Your child may have outgrown the shunt.
- Over-drainage: the shunt is draining more CSF than it should.
- Under-drainage: the shunt is not draining enough CSF.
- Shunt infection.
Signs of a shunt problem
When a shunt is working normally, the CSF drains into the abdomen (belly), the lining around the lungs (pleural space) in the chest, or the heart, depending on the type of shunt. When the shunt is not working, the CSF will build up in the spaces inside the brain (ventricles) and cause the pressure to increase.
In a baby, CSF building up in the brain may cause problems such as the following:
- poor feeding
- vomiting (throwing up)
- seeming sleepy, hard to wake up, or not as awake as usual
- large head; your family doctor can measure this
- bulging "soft spot" (fontanelle) on the top of the head
- seeming irritable (crying easily or for no reason)
- seizures
- very noticeable scalp veins
- slowness at reaching milestones; for example, the baby may be slow to roll over or slow to sit
- "sunset" eyes: the eyes appear to always look down and are not able to look up
- fluid leaking from the incision (cut) site
- pufy skin on top of the shunt tubing
In an older child, CSF building up in the brain may cause problems such as the following:
- headaches
- nausea and vomiting (throwing up)
- tiredness: the child is sleeping more than usual, is difficult to wake up, or does not want to play as usual
- seeming irritable
- changes in personality, behaviour, or school performance
- seizures
- changes in vision
- loss of coordination
- fluid leaking from the incision (cut) site
- pufy skin on top of the shunt tubing
If the shunt tubing becomes disconnected, the CSF will leak out around the tube but will not drain into the abdomen. In this case, you may see swelling or puffiness as the fluid starts to build up around the tubing. This swelling may be seen along the neck or around the "pump" (reservoir) in the head.
Diagnosing shunt problems at the hospital
If your doctor thinks the shunt is not working, your child may need one or more tests.
Imaging tests check for blockage, disconnection, and leakage
- The doctors may use a CT scan, MRI, and/or ultrasound to check the ventricles of the brain to look for blockage in or near the shunt. An ultrasound can only be used if the "soft spot" is still open.
- Doctors may order a "shunt series", which is a series of X-ray pictures that can show if the shunt is disconnected or broken.
- A CSF flow study may also be ordered. This test uses a dye to show the flow of CSF through the shunt. The test can reveal blockage or a leak.
Some children may need medicine so that they sleep during their CT scan or MRI if they have trouble keeping still for the test.
The result of these tests, along with the signs your child is showing, will help the doctor decide if your child's shunt is not working properly.
If the shunt needs to be revised, your child will have an operation
Sometimes the whole shunt needs to be replaced, or sometimes only a part of it needs to be replaced. Your doctor may not know how much of the shunt needs replacing until the surgery is actually being done.
What happens during the operation
Your child is brought down to the operating room. Your child will be given a special "sleep medicine" called general anesthetic to make sure that your child sleeps through the operation and does not feel any pain. The operation usually takes between 1 and 2 hours.
The area from the head to the abdomen (belly) is scrubbed with a special soap. The surgeon makes incisions (cuts) on the head and abdomen.
The shunt is tested to locate the problem. Sometimes the whole shunt needs to be replaced. Other times, only part of the shunt needs replacing. If possible, the old shunt will be removed. Sometimes it is not possible to do this safely and some of the tubing may be left in.
The ventricular (top) end of the tube is placed in a ventricle (fluid space) in the brain. This tube is attached to a valve that controls CSF flow through the shunt. The tube is then tunnelled below the skin to an area of the body where the fluid can be absorbed. One area is the lining of the abdominal cavity, called the peritoneum. Less often, the shunt is connected from the brain to the lining of the lungs (pleural space) inside the chest (a ventriculo-pleural shunt) or veins draining into the heart (ventriculo-atrial shunt).
The surgeon then closes the incisions using either stitches or staples.
After the operation
After the operation, your child will go to the Post Anesthetic Care Unit (PACU) room. Your child will wake up soon after the operation and you will be able to see him as soon as he wakes up. Your child will spend about 1 to 2 hours in the PACU to recover from the anesthetic. Then your child will be returned to his room on the Neurosurgical Unit.
Your child will have a bandage on his head and another on the abdomen. The nurse will check your child often, especially to see how easily your child wakes up, even at night.
Your child will have an intravenous (IV) line after the surgery until he is drinking well.
Your child's doctor will tell you when your child can start normal activity, such as sitting up and walking.
After your child has recovered from the surgery, he can go home. Sometimes a CT scan may be done after surgery to make sure that the pressure in the ventricles has gone down and that the tubing is in good position.
Managing post-operative pain
Your child may experience some pain at the operation site. The nurse will give your child medicine by mouth about every 4 hours. This should control the pain. If it does not control the pain, speak to your child's nurse.
Your child may also learn other ways to control pain, such as blowing bubbles or relaxation breathing. Ask your nurse or Child Life specialist to help you and your child to learn how to do this.
Going home after the operation
It is possible that the shunt will stop working properly after you go home:
- Sometimes the tube can become blocked, come apart, or break.
- Your child may grow taller so that the tube moves out of the abdomen.
- The shunt may become infected.
It is important to watch your child for signs that the shunt is not working properly.
If the shunt is not working properly or is infected, call for medical help right away
Your child needs medical attention right away if you see any signs or symptoms of a shunt problem.
If the shunt is not working, the pressure will return to the brain. Signs that the shunt is not working are listed above under "Signs of a shunt problem." Your child may have the same signs as before the shunt was put in, or he may have new signs.
Signs of a shunt infection include:
- puffiness or redness of the skin around the tube and at incision (cut) sites
- fever
- stiff neck
- fluid coming out of the incision
- loss of appetite or not eating well
- generally feeling sick
- headache
- abdomen (belly) pain
If your child has any of these symptoms, call 911 or your local emergency services right away. Shunt malfunctions or infections that are not treated promptly and appropriately can lead to coma and possibly death.
For more information, please see "Shunt Infections" and "Hydrocephalus and Treatment."
Removing staples or sutures
How your child's staples or stitches are taken out depends on the type of staple or stitch that was used. Your neurosurgeon or nurse practitioner will tell you what type of stitches were used.
- If your child has staples or stitches that need to be taken out, your family doctor will need to do this. The stitches should be taken out about 7 to 10 days after the operation. Staples should be removed about 10 days after the operation. Your surgeon or nurse will tell you when they need to come out.
- If staples were used, you will be given a special remover to take to your family doctor.
- If your child has the kind of stitches that dissolve on their own, you can see your family doctor to have the incision line checked, but the stitches will not need to be taken out.
Following up after the operation
Your surgeon will see your child in a follow-up clinic visit about 6 weeks after you go home. The appointment may be made for you when your child is discharged. If not, call the neurosurgery clinic to make an appointment yourself.
If you have any questions
Any medical questions you may have can be answered by your surgeon. Be sure to write down your questions before you meet the surgeon. Other questions can be answered by your nurse or by a Nurse Practitioner.
Your child's neurosurgeon is:
Your child's nurse practitioner is:
Their telephone number is:
Longer-term: as your child grows to adulthood
A child with hydrocephalus needs to see a doctor often to make sure the shunt is working properly. Several members of a team will help and guide you as your child grows and develops. You should encourage your child to become involved in this ongoing process.
Key points
- If your child's shunt is not working properly, it will cause the CSF to build up in the brain.
- Your child will need an operation to replace all or part of the shunt.
- If you see any signs that the shunt is not working properly or is infected, call 911 or emergency services right away. Your child needs medical attention.