The nurse knows that a shunt procedure is the therapy of choice in almost all cases of hydrocephalus. Which is the most common reason for revision of a child's ventriculoperitoneal shunt?

Rationale: A. Peritonitis: Peritonitis can occur as a complication of a ventriculoperitoneal (VP) shunt, particularly if infection spreads from the peritoneal cavity. While serious, infection is less common than mechanical failure and is not the leading cause of shunt revision. B. Hydrocephalus has increased: Recurrence or progression of hydrocephalus may indicate shunt failure, but it is usually a consequence of valve malfunction or obstruction rather than a separate cause requiring revision on its own. C. Malfunction of the valves: Valve malfunction is the most frequent reason for VP shunt revision. Obstruction, blockage, or mechanical failure of the shunt valves can prevent proper cerebrospinal fluid drainage, necessitating surgical correction to restore normal intracranial pressure. D. Child has grown since placement: Growth can alter the length or positioning of the shunt tubing, but most shunts are designed with extra length to accommodate growth. Growth alone rarely necessitates revision compared to valve or mechanical failure.