Ventriculoperitoneal (VP) Shunt

A ventriculoperitoneal (VP) shunt is a surgically implanted drainage system that continuously moves excess cerebrospinal fluid (CSF) — the clear liquid that cushions the brain and spinal cord — from the fluid-filled spaces inside the brain (called ventricles) to the abdomen, where the body absorbs it naturally.

When CSF cannot drain or circulate properly, it builds up inside the skull and raises the pressure around the brain. The VP shunt relieves this pressure by placing a thin, flexible tube into the ventricle, connecting it through a small valve that controls the flow, and threading a second tube under the skin down to the abdominal cavity. The fluid that arrives in the abdomen is harmlessly absorbed into the bloodstream.

A VP shunt is used to treat hydrocephalus (a condition in which too much cerebrospinal fluid accumulates inside the brain) and other situations where pressure inside the skull is dangerously elevated. The underlying cause of the fluid build-up guides whether a shunt is the right choice.

• Congenital hydrocephalus — hydrocephalus present from birth, often caused by a blockage in the brain's drainage pathways
• Acquired hydrocephalus — fluid build-up developing after a brain injury, stroke, brain tumour, or brain infection such as meningitis
• Normal pressure hydrocephalus (NPH) — a form seen mainly in older adults, causing problems with walking, memory, and bladder control
• Post-haemorrhagic hydrocephalus — excess fluid following bleeding inside or around the brain (for example, after a subarachnoid haemorrhage, which is bleeding around the surface of the brain)
• Hydrocephalus related to a brain or spinal tumour that blocks the normal flow of CSF
• Idiopathic intracranial hypertension (IIH) — raised pressure inside the skull with no obvious cause, when other treatments have not worked

A VP shunt may not be suitable in every case. Your neurosurgeon will consider other options if any of the following apply.

• Active infection anywhere in the body, including the abdomen, because bacteria could travel along the shunt tubing
• Abdominal conditions (such as extensive scarring from previous surgery or active peritonitis, which is infection of the abdominal lining) that would prevent the fluid from being absorbed properly
• Blood-clotting disorders that are not yet under control, raising the surgical risk significantly
• Situations where the blockage can be relieved by a different, less invasive procedure — for example, an endoscopic third ventriculostomy (ETV), in which the surgeon creates a small opening inside the brain to reroute the fluid without a permanent implant

Like all brain surgery, a VP shunt carries recognised risks; your surgical team will discuss your personal risk level before the operation.

• Shunt blockage (obstruction) — the most common long-term problem; the valve or tubing can become blocked, causing CSF to build up again and symptoms to return
• Shunt infection — bacteria can infect the hardware, usually within the first few months after surgery; this nearly always requires the shunt to be removed and replaced
• Over-drainage — the valve releases too much fluid too quickly, causing headaches that are worse when sitting or standing, and sometimes bleeding on the brain's surface (called a subdural haematoma)
• Under-drainage — the valve does not release enough fluid, so pressure inside the skull remains elevated
• Shunt disconnection or migration — a section of tubing can separate or move out of position, requiring further surgery to reposition it
• Bleeding inside the brain (intracranial haemorrhage) at the time of the procedure
• Injury to nearby brain tissue during placement of the ventricular catheter (the tube inserted into the brain)
• Anaesthesia-related complications, which the anaesthesia team will assess separately
• In children, the abdominal tube may need to be lengthened as the child grows

Preparation for VP shunt surgery usually begins several days before the operation. Your neurosurgical team will give you specific instructions; what follows is what is typically required.

Before the day of surgery, patients are usually asked to do the following:

• Fast (have nothing to eat or drink) for a period your team specifies — commonly from midnight before the operation, though your team may adjust this
• Stop taking blood thinners (medicines that prevent clotting) if instructed by the surgical team, as these increase bleeding risk during brain surgery
• Avoid alcohol for at least several days beforehand, as it can affect anaesthesia and healing
• Stop smoking as early as possible before surgery, since smoking impairs wound healing and increases infection risk
• Report all current medicines, supplements, and herbal products to the team, because some interact with anaesthesia or increase bleeding

Standard pre-operative tests typically ordered before a VP shunt include:

• Brain imaging — usually an MRI (magnetic resonance imaging) or CT scan to measure the size of the ventricles and plan the exact placement of the shunt
• Blood tests to check clotting ability, kidney function, and general health
• Chest X-ray and heart tracing (EKG) in older patients or those with existing health conditions
• Neurological examination to record a baseline of the patient's mental and physical function before the procedure

On the day of the procedure, the following steps typically take place, though the exact order and details vary by hospital and individual patient:

• 1. The patient is admitted and identity, consent forms, and allergy information are confirmed.
• 2. An intravenous (IV) line is placed in the arm to deliver fluids and medicines during surgery.
• 3. General anaesthesia is given so the patient is fully asleep throughout the operation.
• 4. The surgical team shaves and cleans a small area of the scalp where the first incision will be made.
• 5. The neurosurgeon makes a small opening in the skull (a burr hole) and carefully inserts the ventricular catheter — the thin tube — into the fluid-filled ventricle.
• 6. The catheter is connected to a programmable or fixed-pressure valve, usually positioned just under the scalp behind the ear.
• 7. A second tube (the peritoneal catheter) is tunnelled under the skin from the valve, down the neck and chest, to a small incision in the abdomen.
• 8. The abdominal end of the tube is placed inside the peritoneal cavity (the space surrounding the organs in the abdomen) so that CSF can drain and be absorbed there.
• 9. All incisions are closed and the patient is moved to a recovery area.

Recovery from VP shunt surgery takes place in stages — first in hospital, then at home — and the timeline varies depending on the patient's age, the reason for the shunt, and any complications. Your team will guide you at each stage.

• Most patients are monitored in an intensive care or high-dependency unit (ICU/HDU) for at least the first night after surgery, so that the brain's response to the shunt can be watched closely
• Neurological checks — assessing alertness, pupil reactions, limb strength, and speech — are carried out frequently in the early hours and days after surgery
• Brain imaging (CT or MRI) is usually repeated within the first day or two to confirm the shunt is correctly positioned and that ventricle size is beginning to decrease
• The scalp and abdominal wound sites are kept clean and dry; the team will advise on when gentle washing is permitted
• Stitches or staples are removed at a follow-up appointment, usually within one to two weeks
• Physical activity is restricted while healing takes place; patients are usually advised to avoid heavy lifting, straining, and contact sports for a period the surgeon specifies
• Swimming and submerging the wounds in water should be avoided until the surgeon confirms the wounds are fully healed
• MRI scans are generally safe with most modern shunt valves, but patients must carry their shunt identification card and inform any future medical team about the implant, as some valve settings can be affected by strong magnetic fields
• Regular follow-up appointments are needed to check shunt function; the frequency will reduce over time if the shunt is working well
• Patients and carers should learn the warning signs of shunt malfunction or infection — returning headaches, vomiting, drowsiness, fever, redness along the shunt track, or swelling at any incision site — and seek urgent medical attention if these occur
• Lifestyle adjustments such as adequate sleep, a balanced diet, and managing any underlying condition (for example, a treated brain tumour or controlled blood pressure) support long-term shunt function