Risks for Shunt Malfunction in Pediatric Hydrocephalus
The Hydrocephalus Clinical Research Network has conducted a prospective observational study of 1036 initial shunt placements at 6 institutions. They selected 21 variables a priori to evaluate as risk factors for shunt failure. Shunt failure and shunt infection were defined in a standard fashion. There were 344 cases of shunt failure in a mean follow up of 400 days. In multivariate analysis, age younger than 6 months was associated with higher risk of shunt failure. Interestingly, the presence of a cardiac comorbidity and the use of an endoscope for shunt placement were both independently associated with higher shunt failure as well. Variables that had no association with shunt failure were: etiology of hydrocephalus, payer, center, valve design, valve programmability, use of ultrasound, size of ventricles, and surgeon experience. These results highlight the effect of young age on shunt survival, independent of underlying etiology. In addition, they corroborate findings from the earlier Endoscopic Shunt Insertion Trial, which showed a trend towards higher failure rates with endoscopic shunt insertion. The authors therefore recommend against routine use of endoscopy with initial shunt insertion.