A ventriculoperitoneal (VP) shunt is a device implanted in the brain of a patient with hydrocephalus, which is a buildup of cerebrospinal fluid (CSF) in the brain. Hydrocephalus is caused by an obstruction that prevents CSF from draining properly. When CSF accumulates, it can enlarge brain ventricles and stretch nerve tissue. A VP shunt is used to drain CSF away from the brain and into the abdomen, where it is easily absorbed. Shunt-placement surgery should be performed immediately after a diagnosis of hydrocephalus, which places dangerous pressure on the brain that can lead to brain damage.
Hydrocephalus can develop at any age, but it is more common in babies and older adults. Hydrocephalus is often present at birth, although it can develop later in life from lesions or tumors within the brain; central-nervous-system infections; or severe head injuries.
Ventriculoperitoneal Shunt Placement Procedure
Performed with the patient under general anesthesia, VP-shunt placement typically takes 90 minutes. To prepare the area for an incision, a small patch of hair is shaved from the head (usually near the top) or behind an ear.
A U-shaped incision is made, and a hole is created in the underlying skull to gain access to the brain. A catheter is then placed within a ventricle of the brain, often with the surgeon using either an endoscope or a computer-guidance system to obtain a clear view of the area.
A second catheter is inserted beneath the surface of the skin toward the back of the head, then threaded down until it reaches the peritoneal cavity of the abdomen. An incision is made in the abdomen to help to properly position the catheter. A very small pump is also placed at the incision site on the head; it is attached to each of the catheters. As fluid levels begin to increase near the brain, the pump activates, safely draining the necessary amount of CSF into the abdomen.
Many of the pumps used in VP-shunt surgery have variable-pressure valves, enabling the flow of CSF out of the brain to be adjusted, which results in more efficient treatment of hydrocephalus. There are several variable-pressure valves available; prior to the procedure, the surgeon determines which is most appropriate based on the patient's condition.
Recovery from Ventriculoperitoneal Shunt Placement
If the shunt is placed in a child, he or she will generally be required to lie flat for a period of 24 hours. The length of the hospital stay following the procedure is usually between 2 and 4 days, during which time the child is monitored and evaluated, and receives intravenous fluids, antibiotics to prevent infection and pain medication as needed.
During the recovery period, and possibly beyond, a patient will likely undergo occupational therapy and counseling to monitor developmental progress and quickly detect any potential problems. Shunts are not permanent, and most need to be replaced. Typically, a VP shunt placed in an infant lasts about 2 years, whereas a shunt placed in an older child or adult lasts for at least 8 years.
Risks of Ventriculoperitoneal Shunt Placement
The procedure for placing a VP shunt is considered safe, but it does have some risks. Risks associated with VP-shunt surgery include:
- Damage to the brain
- Blood clot in the brain
- Swelling of the brain
- Leakage of cerebrospinal fluid
- Shunt failure
- Bowel perforation
Infection, bleeding and adverse reactions to anesthesia are also risks, but they accompany almost any surgical procedure.