Ventriculoperitoneal Shunts

Introduction:

Hydrocephalus is a condition in which excess cerebrospinal fluid (CSF) accumulates in the brain’s ventricles. Ventriculoperitoneal (VP) shunting is a surgical procedure that treats this condition. CSF acts as a shock absorber and protects the brain. It also acts as a carrier system by carrying nourishment to the brain and bringing back waste products away from the brain. The presence of excessive CSF can exert pressure on the brain and can cause various issues. This medical device is usually inserted under general anesthesia.

What Is a VP Shunt?

VP shunt is a medical device whose function is to eliminate excessive CSF from the brain. Fluid buildup can elevate brain pressure, which can be dangerous. A VP shunt drains excess CSF and reduces brain pressure to a safe level. VP shunts consist of a valve and two tubes referred to as catheters. These catheters drain the excess fluid. One catheter eliminates fluid from the brain through a small hole that the physician makes in the skull. This catheter is called the inflow catheter.

The other catheter, called the outflow catheter, runs beneath the skin, carrying the fluid to a drainage site elsewhere in the body. The valve, which is called the pump, controls the shunt so that the fluid is drained as required. VP shunt is of two types, namely:

• Programmable.

• Non Programmable.

In the case of a non-programmable shunt, the physician programs the valve so that it gets activated whenever the fluid attains a certain volume. A non-programmable shunt cannot be adjusted after insertion. On the contrary, a programmable shunt has an external, adjustable valve that the physician can readjust at any time based on the individual’s needs.

Who Requires a VP Shunt?

Individuals of any age can develop hydrocephalus and, hence, may require a VP shunt. However, babies and older adults are more likely to develop hydrocephalus. It is estimated by the National Institute for Neurological Disorders and Stroke (NINDS) that one to two out of every 1000 babies are born with hydrocephalus. Excess fluid can accumulate around the brain for a variety of reasons like:

• Excessive production of CSF.

• Blockages that hinder fluid from flowing throughout the brain.

• Poor absorption of CSF (cerebrospinal fluid) by the blood vessels.

The most common cause of hydrocephalus is blockages. Cysts, tumors, or inflammation in the brain can affect the normal flow of CSF and result in an unsafe accumulation. The following are a few symptoms of hydrocephalus:

• Headaches, irritability, and seizures (a sudden, uncontrolled episode of electrical activity in the brain).

• Large head size.

• Poor appetite, incontinence, and excessive sleepiness.

• Poor coordination, memory loss, and cognitive delays.

• Impaired vision.

How Should One Be Prepared for the VP Shunt Procedure?

The physician may advise the patient to do the following:

• Refrain from drinking alcohol as this may have an effect on surgery and recovery.

• Refrain from taking vitamin E, as it may result in bleeding.

• Avoiding herbal medicines and remedies.

• One must discuss the current medications that one takes, as these might need to be stopped before surgery.

• Any history of allergies should be notified to the physician.

• The patient should be educated about how smoking can affect the surgery.

• Any heart devices that one has or results of any tests for heart conditions should be discussed with the physician.

• Any other medical issues should be brought to the physician’s notice.

• The patient may be advised not to eat after midnight on the night before the day of the surgery. The individual may also be advised about how much water and when it must be drunk before the surgery.

What Is Done During the VP Shunt Procedure?

VP shunt placement is usually done under general anesthesia. One will stay asleep during the procedure and will not experience any pain. The entire procedure will take around 90 minutes. Preoperative instructions will be given by the medical team. The surgical procedure will take place as follows:

• The area behind the ear will be shaved to prepare for the shunting procedure since this is the place where the catheter will be inserted. Catheters are thin, pliable tubes that drain excess fluid.

• A tiny incision will be made by the surgeon behind the ear, and a small hole will be drilled in the skull. One catheter will then be inserted into the brain through this opening. The other catheter will be behind the ear beneath the skin. This tube will then travel down the chest and abdomen, enabling excessive CSF to be eliminated into the abdominal cavity, where it will be absorbed.

• A tiny pump will be attached to both the catheters and will be placed under the skin behind the ear. The pump will get automatically activated to eliminate the fluid when the pressure in the skull gets elevated.

• The pump can also be programmed to activate when the fluid rises to a certain volume.

How Long Does It Take To Recover From a VP Shunt Placement?

The recovery time takes around three to four days. A majority of people will leave the hospital within seven days following the procedure. During the stay at the hospital, the patient’s blood pressure and heart rate will be monitored and preventive antibiotics will be administered. The surgeon will ensure that the shunt is functioning properly before one leaves the hospital.

Are There Any Risks Involved in VP Shunt Placement?

VP shunt placement is a relatively safe procedure. However, a few complications can occur during or after the surgical procedure. Any surgical procedure involves certain risks like infection and excessive bleeding. A few individuals may also experience adverse reactions to anesthesia, like changes in heart rate, breathing difficulties, or changes in blood pressure levels. The following are some of the rare risks associated with VP shunting that, if left untreated, can be serious and potentially life-threatening:

• Blood clots.

• Infections that may occur in the shunt or brain.

• Damage to the brain tissue.

• Bleeding in the brain.

• Swelling of the brain.

Infection is the most common risk that occurs in the first few weeks following shunt placement. Fever, fatigue, headache, abdominal pain, and an increase in blood pressure levels, or experiencing the same symptoms that were present when the shunt was originally placed, can indicate a malfunction or an infection in the shunt.

Conclusion:

Ventriculoperitoneal (VP) shunt placement is a surgical procedure that is done to eliminate excess fluid buildup in the brain. CSF is the fluid that surrounds and provides a cushioning effect to the brain and spinal cord. In certain conditions like hydrocephalus, CSF does not drain appropriately which exerts pressure on the brain. In order to relieve this, a VP shunt is surgically placed to drain the excess fluid from the brain into the peritoneal cavity.