Analysis of shunted hydrocephalus follow-up: What do routine clinic visits yield? What factors affect revision surgery presentation and outcomes?

Pediatric shunt failure in a resource limited Lower-Middle Income Country (LMIC) institution in La Paz, Bolivia

BACKGROUND

Shunt failure is an undesirable but common occurrence following neurosurgical shunting for pediatric hydrocephalus. Little is known about the occurrence of failure in lower-middle income country (LMIC) settings in South America. The objective of this study was to evaluate shunt failure in the sole publicly funded pediatric hospital in La Paz, Bolivia, with limited resources.

METHODS

A retrospective review of all patients at the Children's Hospital of La Paz, Bolivia (Hospital del Niño "Dr. Ovidio Aliaga Uria"), was conducted to identify all patients whose index surgical shunting for hydrocephalus was performed between 2019 and 2023. Categorical, continuous, and shunt failure data were statistically summarized.

RESULTS

A total of 147 unique pediatric patients underwent index ventriculoperitoneal shunting for hydrocephalus in the study period. There were 90 (61%) male and 57 (39%) female patients, with a median age of 2.2 months at index shunting procedure. The most common surgical indications were congenital hydrocephalus (n = 95, 65%), followed by hydrocephalus secondary to congenital defect (n = 25, 17%) and tumor (n = 18, 12%). A total of 18 (12%) of patients experienced inpatient failure during index admission requiring surgical revision at a median time of 12.5 days after index shunting. Postoperative imaging (OR 2.97, P = 0.037) and postoperative infection (OR 3.26, P = 0.032) during index admission both independently and statistically predicted inpatient failure. Of the 96 patients (65%) with postoperative follow-up, 16 (n = 16/96, 17%) patients experienced outpatient failure requiring readmission to hospital and surgical revision at a median time of 3.7 months after discharge. Kaplan-Meier estimations of overall inpatient and outpatient failure in this cohort were 23% (95% CI 14-37) and 28% (95% CI 15-49), respectively.

CONCLUSIONS

Both inpatient and outpatient shunt failures are significant complications in the management of pediatric hydrocephalus in La Paz, Bolivia. We identify multiple avenues to improve these outcomes which are institution-specific based on the review of these failures. Lessons learnt may be applicable to other similarly resourced institutions across South American LMICs.

Developing Predictive Models to Anticipate Shunt Complications in 33,248 Pediatric Patients with Shunted Hydrocephalus Utilizing Machine Learning

INTRODUCTION

Hydrocephalus is a common pediatric neurosurgical pathology, typically treated with a ventricular shunt, yet approximately 30% of patients experience shunt failure within the first year after surgery. As a result, the objective of the present study was to validate a predictive model of pediatric shunt complications with data retrieved from the Healthcare Cost and Utilization Project (HCUP) National Readmissions Database (NRD).

METHODS

The HCUP NRD was queried from 2016 to 2017 for pediatric patients undergoing shunt placement using ICD-10 codes. Comorbidities present upon initial admission resulting in shunt placement, Johns Hopkins Adjusted Clinical Groups (JHACG) frailty-defining criteria, and Major Diagnostic Category (MDC) at admission classifications were obtained. The database was divided into training (n = 19,948), validation (n = 6,650), and testing (n = 6,650) datasets. Multivariable analysis was performed to identify significant predictors of shunt complications which were used to develop logistic regression models. Post hoc receiver operating characteristic (ROC) curves were created.

RESULTS

A total of 33,248 pediatric patients aged 6.9 ± 5.7 years were included. Number of diagnoses during primary admission (OR: 1.05, 95% CI: 1.04-1.07) and initial neurological admission diagnoses (OR: 3.83, 95% CI: 3.33-4.42) positively correlated with shunt complications. Female sex (OR: 0.87, 95% CI: 0.76-0.99) and elective admissions (OR: 0.62, 95% CI: 0.53-0.72) negatively correlated with shunt complications. ROC curve for the regression model utilizing all significant predictors of readmission demonstrated area under the curve of 0.733, suggesting these factors are possible predictors of shunt complications in pediatric hydrocephalus.

CONCLUSION

Efficacious and safe treatment of pediatric hydrocephalus is of paramount importance. Our machine learning algorithm delineated possible variables predictive of shunt complications with good predictive value.

Hydrocephalus in Spina Bifida

Hydrocephalus is the most important co-morbidity in myelomeningocele from a neurosurgical perspective. Historically, 75-80% of patients with myelomeningocele have required treatment with a shunt but recent advances including intra-uterine myelomeningocele closure and ETV-CPC are reducing this burden. The expression of hydrocephalus differs between patients and across the life span. Hydrocephalus impacts the clinical expression of other important co-morbidities including the Chiari II malformation and tethered spinal cord. Shunt failure is often the key stress to prompt symptomatic worsening of these other conditions. Shunt failure may occur with minimal ventricular change on CT or MRI in Spina Bifida patients. Waiting for radiographic changes in symptomatic SB patients with shunts may result in hydrocephalus related fatalities. It is hypothesized but not proven that shunt failure may contribute to respiratory insufficiency and be a risk factor for sudden death in adult patients with spina bifida. Excellence in hydrocephalus management in MMC is essential for proper care, good outcomes, and quality of life for patients and families.