What is the most common complication of a VP shunt?

• A. Obstruction/malfunction
• B. Infection
• C. Overdrainage
• D. Shunt disconnection

Answer: (A)

Obstruction or malfunction is the most common problem with a VP shunt. The shunt must continuously carry CSF from the brain to the peritoneal cavity, but debris, choroid plexus, or protein buildup can clog the catheter—most often the proximal end—and any blockage stops drainage. When CSF can’t escape, intracranial pressure rises and hydrocephalus symptoms recur, which is why obstruction is the typical reason a shunt “fails.” Infections happen, but they’re less frequent overall than mechanical obstruction. Overdrainage and mechanical issues like disconnection occur as well, but they are not as common as obstruction. In kids, watch for signs of rising ICP—headache, vomiting, irritability, lethargy, or a rapidly enlarging head in infants—and treat as shunt malfunction, arranging urgent evaluation for possible revision.