Indications for pediatric external ventricular drain placement and risk factors for conversion to a ventriculoperitoneal shunt

External ventricular drainage in pediatric patients: indications, management, and shunt conversion rates

PURPOSE

Placement of an external ventricular drainage (EVD) is one of the most frequent procedures in neurosurgery, but it has specific challenges and risks in the pediatric population. We here investigate the indications, management, and shunt conversion rates of an EVD.

METHODS

We retrospectively analyzed the data of a consecutive series of pediatric patients who had an EVD placement in the Department of Neurosurgery at Hannover Medical School over a 12-year period. A bundle approach was introduced to reduce infections. Patients were categorized according to the underlying pathology in three groups: tumor, hemorrhage, and infection.

RESULTS

A total of 126 patients were included in this study. Seventy-two were male, and 54 were female. The mean age at the time of EVD placement was 5.2 ± 5.0 years (range 0-17 years). The largest subgroup was the tumor group (n = 54, 42.9%), followed by the infection group (n = 47, 37.3%), including shunt infection (n = 36), infected Rickham reservoir (n = 4), and bacterial or viral cerebral infection (n = 7), and the hemorrhage group (n = 25, 19.8%). The overall complication rate was 19.8% (n = 25/126), and the total number of complications was 30. Complications during EVD placement were noted in 5/126 (4%) instances. Complications during drainage time were infection in 9.5% (12 patients), dysfunction in 7.1% (9 patients), and EVD dislocation in 3.2% (4 patients). The highest rate of complications was seen in the hemorrhage group. There were no long-term complications. Conversion rates into a permanent shunt system were 100% in previously shunt-dependent patients. Conversion rates were comparable in the tumor group (27.7%) and in the hemorrhage group (32.0%).

CONCLUSION

EVD placement in children is an overall safe and effective option in children. In order to make further progress, carefully planned prospective and if possible randomized studies are needed controlling for multivariable aspects.

Invasive Neuromonitoring Modalities in the Pediatric Population

Invasive neuromonitoring has become an important part of pediatric neurocritical care, as neuromonitoring devices provide objective data that can guide patient management in real time. New modalities continue to emerge, allowing clinicians to integrate data that reflect different aspects of cerebral function to optimize patient management. Currently, available common invasive neuromonitoring devices that have been studied in the pediatric population include the intracranial pressure monitor, brain tissue oxygenation monitor, jugular venous oximetry, cerebral microdialysis, and thermal diffusion flowmetry. In this review, we describe these neuromonitoring technologies, including their mechanisms of function, indications for use, advantages and disadvantages, and efficacy, in pediatric neurocritical care settings with respect to patient outcomes.

Neuromonitoring in Children with Cerebrovascular Disorders

BACKGROUND

Cerebrovascular disorders are an important cause of morbidity and mortality in children. The acute care of a child with an ischemic or hemorrhagic stroke or cerebral sinus venous thrombosis focuses on stabilizing the patient, determining the cause of the insult, and preventing secondary injury. Here, we review the use of both invasive and noninvasive neuromonitoring modalities in the care of pediatric patients with arterial ischemic stroke, nontraumatic intracranial hemorrhage, and cerebral sinus venous thrombosis.

METHODS

Narrative review of the literature on neuromonitoring in children with cerebrovascular disorders.

RESULTS

Neuroimaging, near-infrared spectroscopy, transcranial Doppler ultrasonography, continuous and quantitative electroencephalography, invasive intracranial pressure monitoring, and multimodal neuromonitoring may augment the acute care of children with cerebrovascular disorders. Neuromonitoring can play an essential role in the early identification of evolving injury in the aftermath of arterial ischemic stroke, intracranial hemorrhage, or sinus venous thrombosis, including recurrent infarction or infarct expansion, new or recurrent hemorrhage, vasospasm and delayed cerebral ischemia, status epilepticus, and intracranial hypertension, among others, and this, is turn, can facilitate real-time adjustments to treatment plans.

CONCLUSIONS

Our understanding of pediatric cerebrovascular disorders has increased dramatically over the past several years, in part due to advances in the neuromonitoring modalities that allow us to better understand these conditions. We are now poised, as a field, to take advantage of advances in neuromonitoring capabilities to determine how best to manage and treat acute cerebrovascular disorders in children.

Mobilization of Children with External Ventricular Drains: A Retrospective Cohort Study

The implementation of early mobility programs for children with critical illnesses has been growing. Children with acute neurologic conditions that result in the requirement of an external ventricular drain (EVD) may be excluded from attaining the benefits of early mobility programs due to the fear of adverse events. The purpose of this study was to examine the implementation, safety, and outcomes of children with EVDs mobilized by physical therapists. A single-site retrospective cohort study of children with EVDs mobilized by physical therapy (PT) was conducted. Patients aged 3–21 years who were hospitalized from September 2016 to December 2020 were included in this study. Results: Out of a total of 192 electronic health records with EVDs, 168 patients (87.5%) participated in 1601 early mobilization encounters led by physical therapists. No adverse events occurred due to mobilization. Patients mobilized more frequently by PT had a higher level of activity at discharge (p = 0.014), a shorter length of stay (p = 0.001), and a more favorable discharge (p = 0.03). The early mobilization of children with EVDs can be implemented safely without adverse events. Patients mobilized with an EVD are more functional at discharge, spend fewer days in the hospital, and have a more favorable discharge compared to those who do not receive PT.

Intracranial and Cerebral Perfusion Pressure Thresholds Associated With Inhospital Mortality Across Pediatric Neurocritical Care

OBJECTIVES

Targets for treatment of raised intracranial pressure or decreased cerebral perfusion pressure in pediatric neurocritical care are not well defined. Current pediatric guidelines, based on traumatic brain injury, suggest an intracranial pressure target of less than 20 mm Hg and cerebral perfusion pressure minimum of 40-50 mm Hg, with possible age dependence of cerebral perfusion pressure. We sought to define intracranial pressure and cerebral perfusion pressure thresholds associated with inhospital mortality across a large single-center pediatric neurocritical care cohort.

DESIGN

Retrospective chart review.

SETTING

PICU, single quaternary-care center.

PATIENTS

Individuals receiving intracranial pressure monitoring from January 2012 to December 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Intracranial pressure and cerebral perfusion pressure measurements from 262 neurocritical care patients (87 traumatic brain injury and 175 nontraumatic brain injury; 63% male; 8.3 ± 5.8 yr; mortality 11.1%). Mean intracranial pressure and cerebral perfusion pressure had area under the receiver operating characteristic curves of 0.75 and 0.64, respectively, for association of inhospital mortality. Cerebral perfusion pressure cut points increased with age (< 2 yr = 47, 2 to < 8 yr = 58 mm Hg, ≥ 8 yr = 73 mm Hg). In the traumatic brain injury subset, mean intracranial pressure and cerebral perfusion pressure had area under the receiver operating characteristic curves of 0.70 and 0.78, respectively, for association of inhospital mortality. Traumatic brain injury cerebral perfusion pressure cut points increased with age (< 2 yr = 45, 2 to < 8 yr = 57, ≥ 8 yr = 68 mm Hg). Mean intracranial pressure greater than 15 mm Hg, male sex, and traumatic brain injury status were independently associated with inhospital mortality (odds ratio, 14.23 [5.55-36.46], 2.77 [1.04-7.39], and 2.57 [1.03-6.38], respectively; all p < 0.05). Mean cerebral perfusion pressure less than 67 mm Hg and traumatic brain injury status were independently associated with inhospital mortality (odds ratio, 5.16 [2.05-12.98] and 3.71 [1.55-8.91], respectively; both p < 0.01). In the nontraumatic brain injury subset, mean intracranial pressure had an area under the receiver operating characteristic curve 0.77 with an intracranial pressure cut point of 15 mm Hg, whereas mean cerebral perfusion pressure was not predictive of inhospital mortality.

CONCLUSIONS

We identified mean intracranial pressure thresholds, utilizing receiver operating characteristic and regression analyses, associated with inhospital mortality that is below current guidelines-based treatment targets in both traumatic brain injury and nontraumatic brain injury patients, and age-dependent cerebral perfusion pressure thresholds associated with inhospital mortality that were above current guidelines-based targets in traumatic brain injury patients. Further study is warranted to identify data-driven intracranial pressure and cerebral perfusion pressure targets in children undergoing intracranial pressure monitoring, whether for traumatic brain injury or other indications.

A Retrospective Quality Analysis of External Ventricular Drain Infection Rates Following Stroke Diagnoses and Other Brain Injuries: Comparison of Emergency Room and ICU/OR Setting

Objective

The purpose of this study was to analyze the incidence of infections in patients following placement of External Ventricular Drain (EVD) in either the Emergency Room (ER) or the Intensive Care Unit (ICU)/ Operating Room (OR) at a single Comprehensive Stroke Center.

Methods

Retrospective analysis of post-procedure infection rates in 710 patients with EVDs placed on site between 2010 and 2018 was performed. We analyzed cases between sex, age, stroke and non-stroke related and further requirement of conversion of the EVD to a ventriculoperitoneal (VP) shunt.

Results

Significant decrease in EVD related infection (ERIs) rates following the shift in EVD placement from ER to ICU/OR (from 13% to 7.7%, p=.03) among all ages, sex and type of brain injury was observed. Furthermore, our data also shows that the rate of conversion of EVDs to VP shunts is independent of the setting where EVD was placed, but increases in patients who develop ERIs. 23.1% of stroke patients that developed an ERI required a conversion to VP shunt while 67.3% of non-stroke patients that developed an ERI required further VP shunt (p<.001) showing that non-stroke EVD patients with infections are more likely to require VP shunt.

Conclusion

This is one of the larger retrospective studies conducted on EVD related infections. ERIs were significantly higher when EVDs were placed in the ER. Moreover, our results highlight the relation between ERIs and further requirement of conversion EVD to VP shunt. These figures highlight the importance of focusing on infection rates, and the implications CSF infection has on the long-term care of patients.

Emergency imaging in paediatric oncology: a pictorial review

Despite the decline in mortality rates over the last 20 years, cancer remains one of the leading causes of death in children worldwide. Early recognition and treatment for acute oncological emergencies are vital in preventing mortality and poor outcomes, such as irreversible end-organ damage and a compromised quality of life.Imaging plays a pivotal and adjunctive role to clinical examination, and a high level of interpretative acumen by the radiologist can make the difference between life and death. In contrast to adults, the most accessible cross-sectional imaging tool in children typically involves ultrasound. The excellent soft tissue differentiation allows for careful delineation of malignant masses and along with colour Doppler imaging, thromboses and large haematomas can be easily identified. Neurological imaging, particularly in older children is an exception. Here, computed tomography (CT) is required for acute intracranial pathologies, with magnetic resonance imaging (MRI) providing more definitive results later.This review is divided into a 'body systems' format covering a range of pathologies including neurological complications (brainstem herniation, hydrocephalus, spinal cord compression), thoracic complications (airway obstruction, superior vena cava syndrome, cardiac tamponade), intra-abdominal complications (bowel obstruction and perforation, hydronephrosis, abdominal compartment syndrome) and haematological-related emergencies (thrombosis, infection, massive haemorrhage). Within each subsection, we highlight pertinent clinical and imaging considerations.The overall objective of this pictorial review is to illustrate how primary childhood malignancies may present with life-threatening complications, and emphasise the need for imminent patient management.

Criteria for Critical Care Infants and Children: PICU Admission, Discharge, and Triage Practice Statement and Levels of Care Guidance

OBJECTIVES

To update the American Academy of Pediatrics and Society of Critical Care Medicine's 2004 Guidelines and levels of care for PICU.

DESIGN

A task force was appointed by the American College of Critical Care Medicine to follow a standardized and systematic review of the literature using an evidence-based approach. The 2004 Admission, Discharge and Triage Guidelines served as the starting point, and searches in Medline (Ovid), Embase (Ovid), and PubMed resulted in 329 articles published from 2004 to 2016. Only 21 pediatric studies evaluating outcomes related to pediatric level of care, specialized PICU, patient volume, or personnel. Of these, 13 studies were large retrospective registry data analyses, six small single-center studies, and two multicenter survey analyses. Limited high-quality evidence was found, and therefore, a modified Delphi process was used. Liaisons from the American Academy of Pediatrics were included in the panel representing critical care, surgical, and hospital medicine expertise for the development of this practice guidance. The title was amended to "practice statement" and "guidance" because Grading of Recommendations, Assessment, Development, and Evaluation methodology was not possible in this administrative work and to align with requirements put forth by the American Academy of Pediatrics.

METHODS

The panel consisted of two groups: a voting group and a writing group. The panel used an iterative collaborative approach to formulate statements on the basis of the literature review and common practice of the pediatric critical care bedside experts and administrators on the task force. Statements were then formulated and presented via an online anonymous voting tool to a voting group using a three-cycle interactive forecasting Delphi method. With each cycle of voting, statements were refined on the basis of votes received and on comments. Voting was conducted between the months of January 2017 and March 2017. The consensus was deemed achieved once 80% or higher scores from the voting group were recorded on any given statement or where there was consensus upon review of comments provided by voters. The Voting Panel was required to vote in all three forecasting events for the final evaluation of the data and inclusion in this work. The writing panel developed admission recommendations by level of care on the basis of voting results.

RESULTS

The panel voted on 30 statements, five of which were multicomponent statements addressing characteristics specific to PICU level of care including team structure, technology, education and training, academic pursuits, and indications for transfer to tertiary or quaternary PICU. Of the remaining 25 statements, 17 reached consensus cutoff score. Following a review of the Delphi results and consensus, the recommendations were written.

CONCLUSIONS

This practice statement and level of care guidance manuscript addresses important specifications for each PICU level of care, including the team structure and resources, technology and equipment, education and training, quality metrics, admission and discharge criteria, and indications for transfer to a higher level of care. The sparse high-quality evidence led the panel to use a modified Delphi process to seek expert opinion to develop consensus-based recommendations where gaps in the evidence exist. Despite this limitation, the members of the Task Force believe that these recommendations will provide guidance to practitioners in making informed decisions regarding pediatric admission or transfer to the appropriate level of care to achieve best outcomes.

Snap-valve cerebral shunt design for intracranial pressure operation and ultrasound visualization

Cerebral spinal fluid (CSF) shunts are the main treatment for hydrocephalus. They divert excess CSF from the ventricular system to the abdominal, pleural, or intravascular space where it is absorbed. The shunt valve regulates flow based on intracranial pressure (ICP) to maintain a physiologically stable and safe ICP. Shunt malfunction is difficult to detect, life-threatening and common. The present study demonstrates that snap-though buckling (STB) shells can be transformed into pressure-relief valves that act in the normal physiological range of ICP. Three different shell designs in this preliminary experiment were found to have opening and closing pressures that fall within the physiologically normal range of ICP of 6 to 25 cm H₂O. Furthermore, these STB shells demonstrate a valve actuation that is visible by ultrasound and have an implantable form-factor that is similar to currently available shunt valves. The unique characteristics of STB shell valves have potential clinical applications for shunt monitoring using ultrasound imaging and can be fabricated from antibiotic-impregnated materials to mitigate shunt infection. These characteristics make STB valves attractive for future use in cerebral shunt systems.

Surface anatomy for implantation of external ventricular drainage: Some surgical remarks

Background:

External ventricular drainage (EVD) is an emergency process intended to reduce intracranial hypertension resulting from the obstruction of cerebrospinal fluid (CSF) flow. This creates a temporary situation to extract CSF that cannot pass through normally. Knowing the surface anatomy for EVD implantation is important to prevent its inadvertent complications. The external landmarks have been designed in this anatomic study to review the classical landmarks and come up with new landmarks to improve this simple but lifesaving procedure.

Methods:

From November 1998 to October 2012, we implanted 439 EVDs.

Results:

In the first years, we employed usual landmarks to implant 97 EVDs. Since 2002, we used modified anatomical landmarks to implant 342 EVDs directly in the third ventricle.

Conclusion:

Using effective landmarks for EVD implementation allows the catheter to be inserted in the third ventricle. In addition, it permits more precise accuracy to ensure a safer procedure with fewer complications.

Incidence of hemorrhage in the pediatric population with placement and removal of external ventricular drains

OBJECT

External ventricular drains (EVDs) are regularly used in pediatric neurosurgery for diagnostic and therapeutic purposes. Hemorrhage caused by placing an EVD is a common complication noted in the adult literature. In the pediatric literature, on the other hand, only a few articles have assessed the risk of hemorrhage with placement, and none have reported the occurrence of hemorrhage with removal of an EVD. The authors investigated the incidence of hemorrhage with both placement and removal of the EVD in a pediatric population.

METHODS

After obtaining institutional review board approval, a comprehensive database was created to include all pediatric patients who required EVD placement between March 2008 and June 2014 at the authors' institution. A retrospective chart review was completed, and all imaging was reviewed for evidence of hemorrhage with placement and removal of the EVD.

RESULTS

During the designated time period, 73 EVDs were placed in 63 patients (ages 2 weeks-17 years). Indications for EVD placement were as follows: shunt infection/malfunction (21), tumor (12), hydrocephalus (18), hemorrhage (12), edema (4), trauma (1), and other (5). Hemorrhage with placement was noted in 5 of the 50 patients who underwent imaging, with a volume ranging from 0.48 cm3 to 7.7 cm3. Thirty-two patients had imaging after EVD removal, and 7 of these patients were noted to have hemorrhage (volume range 0.012 cm3 to 81.5 cm3).

CONCLUSIONS

The authors found the incidence of hemorrhage at EVD placement to be 10%, and the incidence of hemorrhage on EVD removal to be 21.9% in those patients who underwent imaging after each event. Although none of the hemorrhages were of obvious clinical significance, these data can be useful in decision making, and in discussing the risks of EVDs with the patient's family.

Improvised external ventricular drain in neurosurgery: A Nigerian tertiary hospital experience

Background:

The most common type of hydrocephalus in developing countries is post infective hydrocephalus. Infected cerebrospinal fluid (CSF) however cannot be shunted for the reason that it will block the chamber of the ventriculo-peritoneal (VP) shunt due to its high protein content. In centers where standard external ventricular drain (EVD) sets are not available, improvised feeding tube can be used.

Aim:

The main focus of this study is to encourage the use of improvised feeding tube catheters for EVD when standard sets are not available to improve patients’ survival.

Methodology:

This was a prospective study. Consecutive patients with hydrocephalus that cannot be shunted immediately for high chances of shunt failure or signs of increasing intracranial pressure were recruited into the study. Other inclusion criteria were preoperative brain tumor with possibility of blocked CSF pathway and massive intraventricular hemorrhage necessitating ventricular drainage as a salvage procedure. Standard EVD set is not readily available and too expensive for most of the parents to afford. Improvised feeding tube is used to drain/divert CSF using the standard documented procedure for EVD insertion. Outcome is measured and recorded.

Results:

A total of 28 patients were recruited into the study over a time frame of 2 years. There were 19 (67.9%) male and 9 (32.1%) females with a ratio of about 2:1. Age ranges varied from as low as 7 days to 66 years. The median age of the study sample was 6.5 months while the mean was 173.8 months. Duration of EVD varied from 2 days to 11 days with a median of 7 while the average was 6 days. Eventual outcome following the procedure of EVD showed that 19 (67.9%) survived and were discharged either to go home or to have VP shunt afterwards while 8 (28.6%) of the patients died.

Conclusions:

External ventricular drain can and should be done when it is necessary. Potential mortalities could be reduced by the improvised drainage using a standard feeding tube as described.

Risk factors associated with infections and need for permanent cerebrospinal fluid diversion in pediatric intensive care patients with externalized ventricular drains

BACKGROUND

Externalized ventricular drains (EVDs) are commonly used in pediatric intensive care units (PICU) but few data are available regarding infection rates, infection risks, or factors associated with conversion to permanent cerebrospinal fluid (CSF) diversion.

METHODS

Retrospective observational study of patients managed with EVDs admitted to a tertiary care PICU from January 2005 to December 2009.

RESULTS

Three hundred eighty patients were identified. Neurologic diagnostic groups were externalization of existing shunt in 196 patients (52 %), brain tumor in 122 patients (32 %), intracranial hemorrhage in 23 patients (6 %), traumatic brain injury in 17 patients (5 %), meningitis in 9 patients (2 %), or other in 13 patients (3 %). Six percent of all patients (24/380) had new infections associated with EVD management for an infection rate of 8.6 per 1,000 catheter days. The median time to positive cultures was 7 days (interquartile range 4.75, 9) after EVD placement. Patients with EVD infections had significantly longer EVD duration 6 versus 11.5 days (p = 0.0001), and higher maximum EVD outputs 1.9 versus 1.5 mL/kg/h (p = 0.0017). Need for permanent CSF diversion was associated with higher maximum EVD drainage (1.3 vs. 1.6 mL/kg/h p < 0.0001), longer EVD duration (5 vs. 4 days, p < 0.005), and younger age (4.5 vs. 8 years, p < 0.02) but not intracranial hypertension (72 vs. 82 % of patients, p = 0.4).

CONCLUSIONS

In our large pediatric cohort, EVD infections were associated with longer EVD duration and higher maximum EVD output. Permanent CSF diversion was more likely in patients with higher maximum EVD drainage, longer EVD duration, and younger age.

Hydrocephalus decreases arterial spin-labeled cerebral perfusion

BACKGROUND AND PURPOSE

Reduced cerebral perfusion has been observed with elevated intracranial pressure. We hypothesized that arterial spin-labeled CBF can be used as a marker for symptomatic hydrocephalus.

MATERIALS AND METHODS

We compared baseline arterial spin-labeled CBF in 19 children (median age, 6.5 years; range, 1-17 years) with new posterior fossa brain tumors and clinical signs of intracranial hypertension with arterial spin-labeled CBF in 16 age-matched controls and 4 patients with posterior fossa tumors without ventriculomegaly or signs of intracranial hypertension. Measurements were recorded in the cerebrum at the vertex, deep gray nuclei, and periventricular white matter and were assessed for a relationship to ventricular size. In 16 symptomatic patients, we compared cerebral perfusion before and after alleviation of hydrocephalus.

RESULTS

Patients with uncompensated hydrocephalus had lower arterial spin-labeled CBF than healthy controls for all brain regions interrogated (P < .001). No perfusion difference was seen between asymptomatic patients with posterior fossa tumors and healthy controls (P = 1.000). The median arterial spin-labeled CBF increased after alleviation of obstructive hydrocephalus (P < .002). The distance between the frontal horns inversely correlated with arterial spin-labeled CBF of the cerebrum (P = .036) but not the putamen (P = .156), thalamus (P = .111), or periventricular white matter (P = .121).

CONCLUSIONS

Arterial spin-labeled-CBF was reduced in children with uncompensated hydrocephalus and restored after its alleviation. Arterial spin-labeled-CBF perfusion MR imaging may serve a future role in the neurosurgical evaluation of hydrocephalus, as a potential noninvasive method to follow changes of intracranial pressure with time.