Shunt failure is common among patients undergoing ventriculoperitoneal shunting for treatment of hydrocephalus. The present study examined long-term shunt failure and associated risk factors in pediatric patients by using a national hospitalization database of Thailand.
Patients 17 years or younger who had been admitted to 71 public hospitals in 2012–2017 for first-time ventriculoperitoneal shunting for diseases with known etiology and discharged alive were followed through 2019 to ascertain shunt failure. Shunt survivals were calculated using Kaplan-Meier estimates and time to failure was analyzed to identify risk factors for the first failure by using Cox proportional hazards regression. Differences in risks of subsequent failures with respect to place in the order of failures (i.e., first, second, third) were determined using a cumulative hazard function.
Over a median follow-up of 29.9 months, shunt failure occurred in 33.7% of 2072 patients (median age 8.8 months), with a higher proportion in patients < 1 year than in patients 1–17 years (37.8% vs 28.9%, p < 0.001), and ranged from 26.1% of those having posttraumatic hydrocephalus to 35.9% of those having infectious diseases. The shunt failure rates at 3, 6, and 12 months were 11.5%, 19.0%, and 25.2%, respectively. Patients < 1 year had a higher risk of the first failure than patients 1–17 years (hazard ratio 1.45, 95% CI 1.20–1.76). Among those with shunt failure, 35.8% had multiple failures and 52.9% failed within 180 days after the index shunting. The cumulative hazard of subsequent failure was consistently higher than that of an earlier failure regardless of age and etiology, and the cumulative hazard of the second failure in the patients with 180-day failure was higher than that in the patients in whom shunts failed beyond 180 days.
Shunt failure occurred more frequently in younger pediatric patients. Much attention should be placed on the initial shunt operation so as to mitigate the failure risk. Close follow-up was crucial once patients had developed the failure, because the risk of subsequent failure was more likely than an earlier one among those with multiple failures.