Cerebrospinal fluid shunt placement in the pediatric population: a model of hospitalization cost

Abstract

OBJECT There have been no large-scale analyses on cost drivers in CSF shunt surgery for the treatment of pediatric hydrocephalus. The objective of this study was to develop a cost model for hospitalization costs in pediatric CSF shunt surgery and to examine risk factors for increased costs.

Methods: Data were extracted from the Kids' Inpatient Database (KID) of the Healthcare Cost and Utilization Project. Children with initial CSF shunt placement in the 2009 KID were examined. Patient charge was converted to cost using a cost-to-charge ratio. The factors associated with costs of CSF shunt hospitalizations were examined, including patient demographics, hospital characteristics, and clinical data. The natural log transformation of cost per inpatient day (CoPID) was analyzed. Three multivariate linear regression models were used to characterize the cost. Variance inflation factor was used to identify multicollinearity for each model.

Results: A total of 2519 patients met the inclusion criteria and were included in study. Average cost and length of stay (LOS) for initial shunt placement were $49,317 ± $74,483 (US) and 18.2 ± 28.5 days, respectively. Cost per inpatient day was $4249 ± $2837 (median $3397, range $80-$22,263). The average number of registered nurse (RN) full-time equivalents (FTEs) per 1000 adjusted inpatient days was 5.8 (range 1.6-10.8). The final model had the highest adjusted coefficient of determination (R(2) = 0.32) and was determined to be the best among 3 models. The final model showed that child age, hydrocephalus etiology, weekend admission, number of chronic diseases, hospital type, number of RN FTEs per 1000 adjusted inpatient days, number of procedures, race, insurance type, income level, and hospital regions were associated with CoPID.

Conclusions: A patient's socioeconomic status, such as race, income level, and insurance, in addition to hospital-related factors such as number of hospital RN FTEs, hospital type, and US region, could affect the costs of initial CSF shunt placement, in addition to clinical factors such as hydrocephalus origin and LOS. To create a cost model of initial CSF shunt placement in the pediatric population, consideration of such nonclinical factors may be warranted.

Keywords: CoPID = cost per inpatient day; FTE = full-time equivalent; ICD = International Classification of Diseases; IVH = intraventricular hemorrhage; KID = Kids' Inpatient Database; LOS = length of stay; RN = registered nurse; VIF = variance inflation factor; cerebrospinal fluid shunt; cost analysis; hydrocephalus; pediatric; ventriculoperitoneal shunt.