Common sites for shunts

Ventriculoperitoneal (VP)

Ventriculoperitoneal shunts have the proximal (head end) catheter placed in the ventricles (usually lateral ventricle) and the distal (other) end in the space surrounding the intestines. This space has a fluid similar to CSF, so the CSF mixes with this fluid and is absorbed. If the shunt is infected, the membrane covering the intestines, (the omentum) can block the distal end of the shunt. Occasionally, the fluid is not properly absorbed, and collects in the abdomen. This is often fixed by changing the position of the distal shunt to another area of the abdomen. VP shunts can become infected following bladder surgery, so your urology team would need to be aware of this possibility, and be vigilant after your operation. VP shunts do not need to be changed (revised) routinely in children because of growth. They are changed only if and when they stop working effectively, for example if they block or begin to over drain. VP shunts won’t be suitable if you need peritoneal dialysis.

Ventriculoatrial (VA)

Ventriculoatrial shunts drain from the ventricles into the heart. They are less commonly used than VP shunts. If placed in babies or children, the shunt often has to be changed (revised) when the child grows, to ensure the distal end remains in the heart. Unlike VP shunts, they don’t block if the shunt is infected, but bacteria flows into the bloodstream. This can lead to symptoms such as feeling generally unwell, low-grade fever, night sweats, blood in the urine or a persistent cough. If you have a VA shunt and experience these symptoms, shunt infection can be ruled out through a blood test. 

Lumbar Peritoneal (LP)

Lumbar peritoneal shunts drain from the CSF space around the lumbar spine to the abdomen. This type of shunt is used for draining CSF where there is no blockage through the ventricles, but not enough CSF is being absorbed, such as in communicating hydrocephalus, and Idiopathic Intracranial Hypertension (IIH). They can be combined with gravitational valves to reduce over drainage. Sometimes LP shunts become dislodged from the spine, and sometimes, because the shunt is placed below the brain, it can create a downward pressure on the base of the brain, leading to a condition called Chiari Malformation. More information on Chiari can be found at: www.annconroytrust.org

Ventriculopleural (VPL)

This shunt drains from the ventricles to a thin, fluid-filled layer between the coverings of the lungs. The CSF mixes with this fluid and is absorbed into the bloodstream. It would only be placed here if other sites weren’t suitable. If fluid is not absorbed effectively, it can collect and prevent the lung from expanding. If you have a VPL shunt and are getting short of breath, especially when you exercise, tell your Neurosurgeon as the shunt may have to be moved to a different site.

External shunts

These shunts have the proximal end in the space between the brain and the skull (subarachnoid space), and the distal end is usually placed in the peritoneum. These are used when fluid is collecting around the outside of the brain, but is not trapped within the ventricles. 

Ventriculosubgaleal

This shunt is often used for new or premature babies, who are too small for a shunt, or who may not need a permanent shunt. One end is placed in the ventricle, the other into a ‘pocket’ the surgeon forms between the skin on the baby’s scalp and the underlying tissue. Because the scalp has many small blood vessels, the fluid is easily absorbed directly into the bloodstream.