Cerebrospinal fluid shunt problems in pediatric patients

The Utilization of Computed Tomography in the Pediatric Emergency Department for Patients With Ventriculoperitoneal Shunts

Introduction Despite all the advantages of computed tomography (CT) scanning, there is a significant concern due to the rising use of CT scans in children with ventriculoperitoneal (VP) shunts. High doses of radiation are absorbed by patients, raising their chance of acquiring cancer. Evaluating a potential VP shunt malfunction is a frequent encounter in the pediatric emergency room, often necessitating the utilization of a CT scan. This study aims to recognize and quantify the utilization of CT scans in an emergency setting for pediatric patients with a clinical suspicion of VP shunt malfunction. Methods This retrospective chart review was conducted on patients who visited the emergency department with suspected VP shunt malfunction in a pediatric tertiary care hospital (King Abdullah Specialist Children Hospital), Riyadh, Saudi Arabia. The study included the files of children between the years 2018 and 2019. Results A total of 119 children were included; the main indication for VP shunt insertion was congenital hydrocephalus at 46.8% (n=52). The median number of CT scans done per patient was seven (IQR=3-9). CT findings were abnormal among 55.6% (n=60). The univariate analysis examining the impact of different factors on CT findings showed an association between an abnormal CT finding and female gender (P=0.017), younger age (P=0.03), and the presence of a cerebral cyst (P=0.001); however, subsequent multivariate analysis was not significant for any of these factors. Twenty-two point three percent (n=25) of the patients required neurosurgical intervention, and the associated factors with neurosurgical intervention included changes in activity level (P=0.04), weakness (P=0.004), and altered mental status (P=0.001). Conclusion Children with VP shunts are susceptible to significant radiation exposure through the utilization of CT scans whenever they present to the ER with suspected shunt malfunction during their lifespan, which puts them at risk of radiation-related complications, such as cancers. CT imaging remains a helpful tool aiding physicians in making accurate decisions. However, in this study, almost half of the children had unremarkable CT findings. Thus, it is imperative to rationalize its use by establishing tailored guidelines that delineate the appropriate circumstances warranting its application.

Emergency Point-of-Care Ultrasound Identification of Pediatric Ventriculoperitoneal Shunt Malfunctions

Ventriculoperitoneal shunt malfunctions should be accurately and efficiently diagnosed. In this case series, we describe the use of point-of-care ultrasound to rapidly identify pediatric ventriculoperitoneal shunt tubing fracture, obstruction, and infection.

Ventriculoperitoneal Shunt Fracture Following Application of Halo-Gravity Traction: A Case Report

BACKGROUND

Ventriculoperitoneal (VP) shunt malfunctions are very common, and shunt fracture is one of the most common causes. Shunt fractures are often a result of calcification and tethering, which predispose the tubing to fracture when mechanical stresses are applied. This case report describes a case of shunt fracture following application of halo-gravity traction for correction of spinal deformity.

METHODS

Chart and imaging data for a single case were reviewed and reported in this retrospective case study.

RESULTS

A 10-year-old female, being treated for syndromic scoliosis, underwent posterior surgical release and application of halo-gravity traction. Increasing weight of traction was applied over a period of 6 weeks, for gradual deformity correction. It was noted on the 6-week cervical spine radiograph that the VP shunt had fractured at the base of the neck. The patient was taken to the operating room and intraoperative findings confirmed shunt fracture. This was repaired without complications.

CONCLUSIONS

This case, to our best knowledge, is the first reported occurrence of shunt fracture following application of halo-gravity traction. It demonstrates the importance of careful monitoring of patients with VP shunts, when they are undergoing traction for correction of spinal deformity.

LEVEL OF EVIDENCE

Level IV.

[Clinical scale for the diagnosis of ventriculoperitoneal shunt malfunction in children in Emergency Department]

INTRODUCTION

It is well known that some symptoms in children with ventriculoperitoneal shunt are associated with a higher risk of developing shunt malfunction. However none of those symptoms are sensitive or enough specific enough to diagnose the shunt malfunction.

OBJECTIVE

To develop a diagnostic scale to identify children with an increased risk of shunt malfunction in the Emergency Department.

MATERIAL AND METHODS

This is a prospective study including children aged one to eighteen years old admitted to the Emergency Department between April 2010 and March 2013 with symptoms of ventriculoperitoneal shunt malfunction. Logistic regression Analysis was used to determine whether or not the variables were considered independent risk factors for shunt malfunction. The results led to the development of a diagnostic scale.

RESULTS

A scale was developed using 9 variables (erythema, swelling or discharge from the catheter trajectory, drowsiness, stiff neck, headache, afebrile, age>4 years, vomiting, recent neurological deficit, and time since last surgery ≤ 2 years) with a maximum score of 20 points. It was found that Scale scores ≥ 7 points were associated with an increased risk of shunt malfunction (OR 34.0, 95% CI 15.4-74.9; sensitivity 88.3%, specificity 81.1%, PPV 53.4%, NPV 96.7%).

DISCUSSION

A diagnostic scale is designed for assessing the risk of shunt malfunction, selecting those patients with a higher risk. The use of this scale could help the management of these patients, reducing complementary tests, as well the usual radiation suffered by these children.

Test characteristics of neuroimaging in the emergency department evaluation of children for cerebrospinal fluid shunt malfunction

Objective:

Cerebrospinal fluid (CSF) shunt malfunction is one of the most common life-threatening neurosurgical conditions. In the emergency department (ED), imaging techniques to identify shunt malfunction include the shunt series (SS) and CT scanning of the head. We sought to determine the test characteristics of the SS and CT scan for identifying children with shunt malfunction.

Methods:

We retrospectively reviewed the medical records of children with a CSF shunt who presented to our tertiary care pediatric emergency department and received an SS during a 2-year period from Jan. 1, 2001, to Dec. 31, 2002. A pediatric neuroradiologist reviewed all SS and CT scans. We defined shunt malfunction as present if the child underwent operative shunt revision.

Results:

We identified 437 ED visits by 280 children. Forty-seven SS were read as abnormal. A CT scan was performed in 386 (88.3%) cases and 80 were abnormal. Shunt malfunction was identified in 131 (30.0%) children. Sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio of the SS for identifying cases of shunt malfunction were 30.0%, 95.8%, 72.3%, 75.1%, 7.1 and 0.7, respectively; for the CT scan, they were 61.0%, 82.7%, 64.5%, 80.5%, 3.5 and 0.5, respectively.

Conclusion:

Neuroimaging has a low sensitivity for identifying shunt malfunction. Neurosurgical consultation should be sought if shunt malfunction is clinically suspected, despite normal imaging.

Ventricular peritoneal shunt malfunction after operative correction of scoliosis: report of three cases

BACKGROUND CONTEXT

Two of the most common disease processes associated with hydrocephalus in children are spina bifida and intraventricular hemorrhage of prematurity, both of which are known to be also associated with spinal deformity in later childhood. The occurrence of shunt malfunction after mechanical injury or stress to the hardware has been well documented. Newer techniques in the treatment of neuromuscular scoliosis, including anterior release with segmental fixation, have resulted in more powerful corrections of these large spinal deformities. A new potential cause of shunt malfunction is the aggressive correction of scoliosis.

PURPOSE

To report patients with neuromuscular curves averaging 100° who were subsequently recognized to have perioperative shunt malfunction.

STUDY DESIGN

Three case studies from a university hospital setting were included.

PATIENT SAMPLE

All three children were young adolescents and had-long term shunts. Two of the children had spina bifida and a third had cerebral palsy. All children underwent anterior release of their scoliosis with posterior segmental instrumentation, with unit rods and sublaminar wires. All had significant correction of their scoliosis.

OUTCOME MEASURES

Malfunctioning of the ventriculoperitoneal shunts were recorded.

METHODS

Chart reviews of three cases were analyzed.

RESULTS

Two children had shunt malfunctions within a month of their surgery, and one child had intraoperative recognition and externalization of the shunt.

CONCLUSIONS

Older children undergoing repair of neuromuscular scoliosis are often preadolescents or adolescents who have the same indwelling shunt systems originally implanted in early infancy. The shunt may be brittle and calcified, and the peritoneal catheter may be short. The correction of scoliosis often results in an almost instantaneous growth of a few inches. Because of the potential difficulty in recognizing shunt malfunction in the perioperative period, consideration should be given for elective revision of the peritoneal catheter in children at risk.

Pilot study of radiation dose reduction for pediatric head CT in evaluation of ventricular size

BACKGROUND AND PURPOSE

CT is a ubiquitous, efficient, and cost-effective method to evaluate pediatric ventricular size, particularly in patients with CSF shunt diversion who often need emergent imaging. We therefore sought to determine the minimum dose output or CT dose index required to produce clinically acceptable examinations.

MATERIALS AND METHODS

Using a validated noise insertion method and CT projection data from 22 patients, standard pediatric head CT images were reconstructed with weighted filtered back-projection and sinogram-affirmed iterative reconstruction corresponding to routine, 25%, and 10% dose. Reconstructed images were then evaluated by 3 neuroradiologists (blinded to dose and reconstruction method) for ventricular size, diagnostic confidence, image quality, evidence of hemorrhage, and shunt tip location, and compared with the reference standard.

RESULTS

There was no significant difference in the ventricular size ranking, and the sensitivity for moderate to severe hydrocephalus was 100%. There was no significant difference between the full-dose level and the ventricular size rankings at the 25% or the 10% dose level for either reconstruction kernel (P > .979). Diagnostic confidence was maintained across doses and kernel. Hemorrhage was more difficult to identify as image quality degraded as dose decreased but was still seen in a majority of cases. Shunts were identified by all readers across all doses and reconstruction methods.

CONCLUSIONS

CT images having dose reductions of 90% relative to routine head CT examinations provide acceptable image quality to address the specific clinical task of evaluating ventricular size.

Cranial computed tomography utilization for suspected ventriculoperitoneal shunt malfunction in a pediatric emergency department

BACKGROUND

Computed tomography (CT) scan, the largest medical source of ionizing radiation in the United States, is used to test for failure of ventricular peritoneal shunts.

STUDY OBJECTIVES

To quantify the exposure to cranial CT scans in pediatric patients presenting with symptoms of shunt malfunction, and to measure the association of signs and symptoms with clinical shunt malfunction and the need for neurosurgical intervention within 30 days of presentation.

METHOD

This was a quality improvement study evaluating a pathway used by providers in a tertiary care pediatric emergency department with 85,000 patient visits per year, by retrospective chart review of 223 patient visits for suspected shunt malfunction. We determined the median CT scan per patient per year and the association of signs and symptoms on the pathway with radiological signs of shunt failure and neurosurgical intervention within 30 days of scan.

RESULTS

The median exposure was 2.6 (interquartile range 1.44-4.63) scans per patient per year. Among 11 signs and symptoms, none was associated with radiologic shunt failure. Neurosurgical intervention within 30 days was positively associated with bulging fontanelle (adjusted odds ratio [AOR] 11.78; 95% confidence interval [CI] 1.67-83.0) and behavioral change (AOR 3.01; 95% CI 1.14-7.93), and negatively associated with seizure (AOR 0.13; 95% CI 0.02-0.79) and fever (AOR 0.15; 95% CI 0.04-0.55).

CONCLUSIONS

Patients with ventricular peritoneal shunts underwent many cranial CT scans each year. None of the signs or symptoms included on the clinical pathway was predictive of changes on CT scan.

Sonographic localization of a nonpalpable shunt: Ultrasound-assisted ventricular shunt tap

Background:

Patients frequently present to the emergency department (ED) for evaluation of cerebrospinal fluid (CSF) shunt malfunction, often requiring urgent management. A typical evaluation in the emergency room setting includes a thorough history and physical examination, noncontrasted head computed tomography (CT), shunt series, and occasionally a ventricular shunt tap.

Case Description:

We present the case of a 53-year-old male who initially presented to the ED in acute status epilepticus. His history was notable for seizures and multiple craniectomies and cranioplasties with subsequent placement of a ventriculoperitoneal shunt secondary to traumatic brain injury. Imaging in the ED suggested possible shunt failure. No previous imaging was available for comparison, and therefore a ventricular shunt tap was attempted. Initially, the tap could not be performed, as the shunt was not palpable secondary to the thickness of his scalp and location of the reservoir near his complex cranial reconstruction site. We report, for the first time, the utility of emergency ultrasound (EUS) to aid in such an encounter.

Conclusion:

EUS revealed the exact location of his shunt reservoir, and therefore enabled the shunt tap, which ultimately led to the discovery of the patient's proximal shunt failure in a setting that may have otherwise been missed. The patient underwent urgent shunt revision with a good outcome.

Additive value of nuclear medicine shuntograms to computed tomography for suspected cerebrospinal fluid shunt obstruction in the pediatric emergency department

OBJECTIVE

To measure the predictive value of nuclear medicine studies (cerebrospinal fluid [CSF] shuntograms) and radiographic studies (computed tomographic [CT] scans) in a cohort of children undergoing evaluation for suspected shunt obstruction in a tertiary care pediatric emergency department (ED).

METHODS

A retrospective chart review was conducted on patients younger than 18 years who presented to the pediatric ED of the Children's Hospital of Western Ontario and had both CT of the head and a CSF shuntogram ordered by the attending pediatric emergency medicine physician between December 1998 and April 2003 because of suspected shunt obstruction.

RESULTS

A total of 69 patients were evaluated for suspected shunt obstruction in the ED during this period with both a CT and a CSF shuntogram. Twenty-seven patients (39.1%) subsequently required corrective surgery for suspected shunt obstruction that was confirmed intraoperatively. The CT scans showed abnormalities suggestive of CSF shunt obstruction in 21 of the patients who required surgery (sensitivity, 77.8%; negative predictive value, 82.4%), whereas the CSF shuntograms showed abnormalities suggestive of CSF obstruction in 25 of the patients who required surgery (sensitivity, 92.6%; negative predictive value, 92.6%). The CT scans and the shuntograms combined revealed abnormalities suggestive of CSF shunt obstruction in 26 of the 27 patients who required surgery (sensitivity, 96.3%; negative predictive value, 97.4%).

CONCLUSIONS

Over one third of pediatric ED patients evaluated with CT and CSF shuntograms required surgical management. Sensitivity was increased with CT and CSF shuntogram compared with CT alone. Prospective studies are required to assess the use of radiographic and nuclear medicine tests for the shunt evaluation in conjunction with the development of a clinical prediction rule for the pediatric emergency physician.

Signs and symptoms of cerebrospinal fluid shunt malfunction in the pediatric emergency department

OBJECTIVES

Pediatric patients with cerebrospinal fluid shunts frequently present to the emergency department for evaluation of possible shunt malfunction. Most shunt studies appear in the neurosurgical literature. To our knowledge, none have reviewed presenting signs and symptoms of shunt malfunction in patients who present to the pediatric emergency department. The study objective was to evaluate the medical record of children with cerebrospinal fluid shunts who presented to a pediatric emergency department to determine if any signs and/or symptoms were predictive of shunt malfunction.

METHODS

A retrospective chart review was conducted on 352 pediatric patients aged 0 to 18 years, who presented to the pediatric emergency department between January 1, 1998, and December 31, 2002, with signs and/or symptoms that prompted an evaluation for possible shunt malfunction.

RESULTS

Univariate analysis of all signs and symptoms revealed lethargy (odds ratio, 1.99; 95% confidence interval, 1.15-3.42; P = 0.02) and shunt site swelling (odds ratio, 2.56, 95% confidence interval, 1.08-6.07, P = 0.03) to be significantly predictive of shunt malfunction. Logistic regression analysis continued to show significance for lethargy (odds ratio, 2.20; bias-corrected 95% confidence interval, 1.11-3.63) and shunt site swelling (odds ratio, 3.10; bias-corrected 95% confidence interval, 1.38-9.05), but found no other study variable to be significant. Bootstrap resampling validated the importance of the significant variables identified in the regression analysis.

CONCLUSIONS

In this study, lethargy and shunt site swelling were predictive of shunt malfunction. Other signs and symptoms studied did not reach statistical significance; however, one must maintain a high index of suspicion when evaluating children with an intracranial shunt because the presentation of malfunction is widely varied. A missed diagnosis can result in permanent neurological sequelae or even death.

CSF shunt failure with stable normal ventricular size

OBJECTIVE

The purpose of this study was to review the clinical features of a group of patients in whom ventricular enlargement was not a manifestation of prolonged CSF shunt obstruction.

RESULTS

Twelve patients who had prolonged symptoms consistent with CSF shunt failure and stable normal ventricular size were demonstrated at the time of surgery to have obstruction of their CSF shunts.

CONCLUSION

Ventricular enlargement is a common but not sine qua non indicator of CSF shunt failure, even after weeks or months of elevated intracranial pressure, and therefore cannot be relied upon for the diagnosis of CSF shunt failure. Although an increase in ventricular size is usually seen relatively early in the course of shunt malfunction, stable normal ventricular size in patients with symptoms and signs that are consistent with shunt failure can delay the diagnosis with potentially serious adverse consequences.

Hidrocefalia derivada na infância: um estudo clínico-epidemiológico de 243 observações consecutivas

Os objetivos deste estudo foram analisar as características epidemiológicas e clínicas de 243 crianças com hidrocefalia derivada, acompanhadas durante 1 a 27 anos, assim como identificar os fatores relacionados aos distúrbios psicomotores, epilepsia e ao óbito. A meningite pós-derivação e os distúrbios mecânicos do sistema foram as complicações mais freqüentes (22,3% e 30,7%, respectivamente). A média de derivação por paciente foi 1,47. Distúrbios motores graves ocorreram em 34,3%, déficit cognitivo em 58,5% e epilepsia em 43,6% dos pacientes. Os distúrbios motores correlacionaram-se positivamente com o grau da hidrocefalia. Houve maior incidência de déficit cognitivo e epilepsia nos casos de hidrocefalia pós-meningite. O óbito ocorreu em 52 pacientes e estes apresentaram um percentual maior de neoplasia do sistema nervoso central e de distúrbios motores na última avaliação, assim como de retirada da primeira derivação por meningite precoce, ocorrida até 2 meses após a derivação.

Radiographic evaluation for suspected cerebrospinal fluid shunt obstruction

OBJECTIVE

To measure the predictive value of plain radiographs (shunt series) and computed tomography (CT) scans in a group of children undergoing evaluation for suspected shunt obstruction in a tertiary care pediatric emergency department (ED).

METHODS

Radiology reports were reviewed for all ED patients who underwent a shunt series over an 18-month period. Two investigators categorized all reports as normal, possibly abnormal (eg, kink in shunt tubing, no prior CT scan for comparison), or abnormal (with definite evidence of shunt dysfunction, such as shunt tubing disconnection and increase in ventricular size since prior CT scan). Studies for which there was disagreement were re-read independently by a pediatric radiologist. Medical records were reviewed to determine outcomes.

RESULTS

A total of 233 patients had shunt series and CT scans ordered. Of these, 60 patients subsequently required surgery for shunt obstruction. The shunt series revealed abnormalities in 12 patients (sensitivity, 20%; negative predictive value, 22%), whereas CT scans showed definite or possible abnormalities in 50 patients (sensitivity, 83%; negative predictive value, 93%). Combined, the two tests detected 53 shunt obstructions (sensitivity, 88%; negative predictive value, 95%). Two obstructed patients had abnormalities on shunt series that would not have been suspected after physical examination or CT scan.

CONCLUSIONS

Over one quarter of pediatric ED patients evaluated radiographically for suspected shunt obstruction required surgical management. One in eight obstructed patients had normal radiographic studies. Routine performance of shunt series had a low overall yield but on rare occasions detected abnormalities that were missed by CT. Prospective studies are needed to improve the use of radiographic tests for shunt evaluation and determine clinical indications for further workup when studies are normal.

Predictors of ventriculoperitoneal shunt pathology

BACKGROUND

Diagnosis of ventriculoperitoneal (VP) shunt pathology remains a dilemma in patients with nonspecific constitutional signs and symptoms. Eosinophilia has been described in association with shunt infection and malfunction. Our purpose was to further define the relationship of eosinophilia and shunt pathology and to determine other predictors of VP shunt infection and malfunction.

METHODS

Records of all patients admitted with a suspected VP shunt infection or malfunction were reviewed. The following data were abstracted: age; reason for and age at initial shunt placement; number of revisions; date of last revision; history of fever or vomiting; ventricular fluid cell count; differential and culture; complete blood count and differential; need for shunt revision or replacement; and use of antibiotics. After exclusion of patients admitted for initial shunt placement, the remainder were divided into three groups: those with shunt infection; those with shunt malfunction; and those without documented infection or malfunction.

RESULTS

Of 12 patients with shunt infection and 69 with shunt malfunction, 2 and 11, respectively, had eosinophilia defined as > or =5%. The presence of eosinophilia had a 96% positive predictive value for shunt pathology and raised the pretest probability of pathology from 84% to a post test probability of 96%. The combination of fever history and ventricular fluid neutrophils >10% had a 99% specificity for shunt infection, had a 93 and 95% positive and negative predictive value, respectively, and raised the pretest probability of infection from 12% to a posttest probability of 92%.

CONCLUSIONS

In patients suspected of having a VP shunt malfunction, the presence of > or =5% eosinophils in the ventricular fluid indicates shunt pathology. The combination of fever and ventricular fluid neutrophils > 10% is predictive of shunt infection.

Training paramedics: emergency care for children with special health care needs

OBJECTIVE

To enhance knowledge and comfort related to the emergency care of children with special health care needs (CSHCN) through an innovative continuing education program for paramedics.

METHODS

A self-study program presenting in-depth information about common problems that affect the assessment and management of a child's airway, breathing, circulation, disability, and environment (ABCDEs), regardless of the child's diagnosis, was developed. This program used a manual, a video, practice mannequins, and skills evaluations to teach skills to paramedics employed at a municipal fire department.

RESULTS

Pre- and posttraining surveys found that the paramedics were significantly more comfortable with the assessment and management of CSHCN after the completion of the self-study program, with a pretraining average of 2.83 and posttraining average of 4.20 on a five-point Likert-type scale, t(37) = 12.87, p < 0.001. A skills evaluation showed that skills performance varied widely across 21 skills, ranging from skills mastery to low skills knowledge. On the posttraining survey, between 74% and 94% of the paramedics rated each topic (tracheostomies, indwelling central venous catheters, cerebrospinal fluid shunts, gastrostomies, child abuse, and latex allergy) as applicable to their practices as paramedics.

CONCLUSION

Given the growing population of CSHCN, it is important to provide specialized education to increase an EMS provider's preparedness to respond to emergency situations involving children with special health care needs.