Object
Cerebrospinal fluid shunts are the mainstay of the treatment of hydrocephalus. In past studies, outcomes of shunt surgery have been analyzed based on follow-up of 1 year or longer. The goal of the current study is to characterize 30-day shunt outcomes, to identify clinical risk factors for shunt infection and failure, and to develop statistical models that might be used for risk stratification.
Methods
Data for 2012 were obtained from the National Surgical Quality Improvement Program-Pediatrics (NSQIP-P) of the American College of Surgeons. Files with index surgical procedures for insertion or revision of a CSF shunt composed the study set. Returns to the operating room within 30 days for shunt infection and for shunt failure without infection were the study end points. Associations with a large number of potential clinical risk factors were analyzed on a univariate basis. Logistic regression was used for multivariate analysis.
Results
There were 1790 index surgical procedures analyzed. The overall rates of shunt infection and shunt failure without infection were 2.0% and 11.5%, respectively. Male sex, steroid use in the preceding 30 days, and nutritional support at the time of surgery were risk factors for shunt infection. Cardiac disease was a risk factor for shunt failure without infection, and initial shunt insertion, admission during the second quarter, and neuromuscular disease appeared to be protective. There was a weak association of increasing age with shunt failure without infection. Models based on these factors accounted for no more than 6% of observed variance. Construction of stable statistical models with internal validity for risk adjustment proved impossible.
Conclusions
The precision of the NSQIP-P dataset has allowed identification of risk factors for shunt infection and for shunt failure without infection that have not been documented previously. Thirty-day shunt outcomes may be useful quality metrics, possibly even without risk adjustment. Whether important variation in 30-day outcomes exists among institutions or among neurosurgeons is yet unknown.