A ventriculoperitoneal, or VP, shunt is a device that is implanted into the brain in patients with hydrocephalus. Hydrocephalus is characterized by a build up of excess cerebrospinal fluid, or CSF, within the brain as a result of an obstruction that prevents proper fluid drainage. This neurological condition involves an enlargement of the brain ventricles and a stretching of nerve tissue within the brain as a result of CSF accumulation. It is usually present at birth, although it can develop later in life as a result of lesions or tumors within the brain, central nervous system infections or severe head injuries.
The VP shunt is used to drain the cerebrospinal fluid away from the brain and into the abdomen, where it can be easily absorbed. It is recommended to have a shunt placement surgery shortly after a diagnosis of hydrocephalus because this condition results in dangerous pressure on the brain that can lead to brain damage.
The Ventriculoperitoneal Shunt Procedure
Performed with the patient under general anesthesia, the VP shunt placement procedure typically lasts for approximately 90 minutes. To prepare the area for an incision, a small patch of hair must be shaved from the head, generally behind an ear or near the top of the head.
A U-shaped incision is made and a hole is created in the underlying skull bone 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 through the body, typically until it reaches the peritoneal cavity of the abdomen. An incision is made in the abdomen to help in the proper positioning of the catheter. A very small pump is also placed at the incision site on the head and it is attached to each of the catheters. As fluid levels begin to increase near the brain, the pump activates and safely drains the necessary amount of CSF down to the abdomen.
Many of the pumps used in VP shunt surgery today offer variable pressure shunting to moderate the flow of CSF out of the brain. This technique adjusts the pressure of the valve for more efficient treatment of hydrocephalus. There are several different variable pressure valves available, and prior to the procedure the surgeon will determine which one is most appropriate based on an evaluation of the patient’s individual condition.
Recovery from a Ventriculoperitoneal Shunt Procedure
If the surgery has been performed on a child, the patient 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 two and four days, during which time the patient can be monitored and evaluated as well as receive intravenous fluids, antibiotics to prevent infection and pain medication if needed.
During the recovery period and possibly beyond, patients will likely need to undergo occupational therapy and counseling to monitor developmental progress and detect any potential delays as soon as possible. Shunts are not permanent, and most will need to be replaced in time. Typically a VP shunt placed in an infant will require replacement in approximately two years, and the shunt used in older children and adults generally lasts for at least eight years.
Risks of a Ventriculoperitoneal Shunt Procedure
The procedure for placing a VP shunt is considered safe, however all forms of surgery carry some risk. The risks associated with a VP shunt surgery include infection, bleeding, adverse reaction to anesthesia, damage to the brain, blood clot in the brain, swelling of the brain, leaking cerebrospinal fluid, seizures, shunt failure or a bowel perforation.