Trends in Ventriculostomy-Associated Infections and Mortality in Aneurysmal Subarachnoid Hemorrhage: Data From the Nationwide Inpatient Sample

Diagnostic Accuracy of Optic Nerve Sheath Diameter Using Ultrasonography for Raised Intracranial Pressure in Pediatric Patients - A Systematic Review and Meta-Analysis

PURPOSE

Detecting increased intracranial pressure early in pediatric patients is essential, as early initiation of therapy prevents morbidity and mortality. The objective of this study was to determine the diagnostic accuracy of the optic nerve sheath diameter (ONSD) measured via ultrasound for the prediction of increased intracranial pressure.

METHODS

Four databases, namely, PubMed, EMBASE, Scopus, and CINAHL, were searched for this systematic review and meta-analysis. The study's predefined inclusion criteria considered diagnostic accuracy, cross-sectional, prospective observational, and retrospective studies with a focus on children with elevated intracranial pressure from causes such as traumatic brain injury and cerebral edema, the diagnostic accuracy of the optic nerve sheath diameter measured using ultrasound was assessed. The primary outcome measures included sensitivity and specificity. The study included invasive monitoring (external ventricular drain) and noninvasive measures as the gold standards for increased intracranial pressure. Two authors extracted and reviewed the data. Baseline data, outcome measures, and diagnostic accuracy data were extracted.

RESULTS

Twenty-five studies with 1591 patients and 3143 ONSD measurements via ultrasound were analyzed. The pooled sensitivity and specificity of the ONSD measured via ultrasound for the prediction of increased intracranial pressure were 92% (86%-96%) and 89% (77%-96%), respectively. The pooled positive and negative likelihood ratios were 8.6 and 0.08, respectively.

CONCLUSION AND RELEVANCE

Optic nerve ultrasonography stands out as a precise and valuable diagnostic tool applicable across diverse patient populations and clinical scenarios. We recommend routine ocular ultrasound for optic nerve sheath diameter measurement in pediatric patients to increase the accuracy of diagnosing increased intracranial pressure.

Postprocedural Complications of External Ventricular Drains: A Meta-Analysis Evaluating the Absolute Risk of Hemorrhages, Infections, and Revisions

BACKGROUND

External ventricular drain (EVD) insertion is often a lifesaving procedure frequently used in neurosurgical emergencies. It is routinely done at the bedside in the neurocritical care unit or in the emergency room. However, there are infectious and noninfectious complications associated with this procedure. This meta-analysis sought to evaluate the absolute risk associated with EVD hemorrhages, infections, and revisions. The secondary purpose was to identify and characterize risk factors for EVD complications.

METHODS

We searched the MEDLINE (PubMed) database for "external ventricular drain," "external ventricular drain" + "complications" or "Hemorrhage" or "Infection" or "Revision" irrespective of publication year. Estimates from individual studies were combined using a random effects model, and 95% confidence intervals (CIs) were calculated with maximum likelihood specification. To investigate heterogeneity, the t2 and I2 tests were utilized. To evaluate for publication bias, a funnel plot was developed.

RESULTS

There were 260 total studies screened from our PubMed literature database search, with 176 studies selected for full-text review, and all of these 176 studies were included in the meta-analysis as they met the inclusion criteria. A total of 132,128 EVD insertions were reported, with a total of 130,609 participants having at least one EVD inserted. The pooled absolute risk (risk difference) and percentage of the total variability due to true heterogeneity (I2) for hemorrhagic complication was 1236/10,203 (risk difference: -0.63; 95% CI: -0.66 to -0.60; I2: 97.8%), infectious complication was 7278/125,909 (risk difference: -0.65; 95% CI: -0.67 to -0.64; I2: 99.7%), and EVD revision was 674/4416 (risk difference: -0.58; 95% CI: -0.65 to -0.51; I2: 98.5%). On funnel plot analysis, we had a variety of symmetrical plots, and asymmetrical plots, suggesting no bias in larger studies, and the lack of positive effects/methodological quality in smaller studies.

CONCLUSIONS

In conclusion, these findings provide valuable information regarding the safety of one of the most important and most common neurosurgical procedures, EVD insertion. Implementing best-practice standards is recommended in order to reduce EVD-related complications. There is a need for more in-depth research into the independent risk factors associated with these complications, as well as confirmation of these findings by well-structured prospective studies.

Cerebrospinal fluid white cell count to red cell count ratio as a predictor of ventriculitis in patients with external ventricular drains

INTRODUCTION

External ventricular drain (EVD) associated ventriculitis is a complication of EVD placement associated with significant morbidity and mortality. Gold-standard for EVD associated bacterial ventriculitis diagnosis involves cerebrospinal fluid (CSF) sampling from the EVD with microscopy, culture and sensitivity testing. The ratio of white blood cells to red blood cells has anecdotally been considered a predictive factor in diagnosing EVD associated ventriculitis, however no study has been done demonstrating this.

METHODS

A retrospective cross-sectional study was designed to assess whether the ratio of CSF white blood cells to red blood cells could be used to diagnose EVD associated ventriculitis. Data was collected for all patients undergoing EVD insertion at a major neurosurgical unit in Sydney, Australia. A receiver operator characteristics (ROC) curve was used to determine if this ratio was useful, and Youden's index was calculated to determine the appropriate cut-off point.

RESULTS

This sample of n = 157 consecutive patients a total of 29 patients were diagnosed with ventriculitis. The area under the ROC curve was significant (0.706, P <0.001), and Youden's index demonstrated an appropriate cut-off point was a ratio of 1:106.

DISCUSSION

CSF parameters have long been considered predictive of EVD associated ventriculitis. We demonstrated that using a component of routine testing it is possible to accurately predict a ventriculitis diagnosis. As the ratio is used, it enables discrimination in a raised white blood cell count due to local trauma with interventricular bleeding.

CONCLUSION

CSF white blood cell to red blood cell ratio is an appropriate diagnostic test for ventriculitis.

Trends in Utilization of Temporary and Permanent Cerebrospinal Fluid Diversion and Catheter Cerebral Angiography for Patients with Aneurysmal Subarachnoid Hemorrhage in the United States

INTRODUCTION

We sought to analyze the rate of utilization of methods of cerebrospinal fluid diversion over time in a nationally representative cohort of patients admitted with aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

The Nationwide Inpatient Sample was queried for patients admitted with aSAH from 2006 to 2018. Patients who received external ventricular drainage (EVD), lumbar drainage, ventriculoperitoneal shunt (VPS), and cerebral angiography were then identified. A Cochrane-Armitage test was conducted to assess the linear trend of proportions of EVD, lumbar drains, VPS, and mean cerebral angiograms per admission. Four regression analyses were conducted to infer the association of baseline variables to EVD, lumbar drain, VPS, and mean number of cerebral angiographies.

RESULTS

A total of 133,567 admissions were identified from 2006-2018 involving aSAH. Of these, 41.82% received EVD, 6.22% received lumbar drainage, 10.58% received VPS, and 75.03% had cerebral angiograms. There was an average upward trend of 1.57% in annual EVD utilization, downward trend of -0.28% in utilization of lumbar drainage, no changes in VPS utilization, and an upward trend of 0.04 angiograms per year (P < 0.001). There was a higher proportion of Black patients treated with EVD and VPS in both urban teaching hospitals and large hospitals.

CONCLUSIONS

Our results show the temporal trends in utilization of temporary and permanent methods of cerebrospinal fluid diversion and catheter cerebral angiography among patients with aSAH in the United States. The underutilization of VPS following EVD and the differences in EVD and VPS utilization depending on race and hospital size deserve further exploration.

Trends in Admissions and Outcomes for Treatment of Aneurysmal Subarachnoid Hemorrhage in the United States

BACKGROUND

Lifestyle modifications and advances in surgical and endovascular techniques for treating unruptured intracranial aneurysm (UIA) have vastly evolved over the last few decades and may have reduced the incidence of aneurysmal subarachnoid hemorrhage (aSAH). However, the actual impact of these changes on the rates and outcomes of aSAH remain unexplored. Thus, we studied national aSAH admissions and outcome trends and changes of major risk factors over time.

METHODS

We queried the National Inpatient Sample between 2006 and 2018 to identify adult patients admitted and treated for UIA or ruptured aneurysm with aSAH. The Cochran-Armitage test was conducted to assess the linear trend of proportion of prevalence, inpatient mortality, hypertension, and current smoking status among aSAH admissions. Multivariable logistic regression was conducted to assess the odds of presenting with aSAH versus UIA, in addition to the odds of inpatient mortality among patients with aSAH.

RESULTS

A total of 159,913 patients presented with UIA and 133,567 presented with aSAH. Admissions for aSAH decreased by 0.97% (p < 0.001) per year. Current smoking and hypertension were associated with higher odds of being admitted for aSAH compared with the treatment for UIA (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.29-1.48; OR 1.15, 95% CI 1.08-1.22, respectively). Compared with White patients, Black patients (OR 1.32, 95% CI 1.21-1.43), Hispanic patients (OR 1.38, 95% CI 1.25-1.52), and patients of other races and/or ethnicities (OR 1.73, 95% CI 1.54-1.95) had a higher chance of presenting with aSAH. Rates of inpatient mortality among aSAH admissions showed no change over time (p = 0.21). Among patients admitted with aSAH, current smoking and hypertension showed an upward trend of 0.58% (p < 0.001) and 1.60% (p < 0.001) per year, respectively.

CONCLUSIONS

Despite a downward trend in the annual frequency of hospitalizations for aSAH, inpatient mortality rates for patients undergoing treatment of the ruptured aneurysm have remained unchanged in the United States. Smoking and hypertension are increasingly prevalent among patients with aSAH. Thus, efforts to control these modifiable risk factors must be further strengthened.

A Narrative Review of the Published Literature, Hospital Practices, and Policies Related to External Ventricular Drains in the United States: The External Ventricular Drain Publications, Practices, and Policies (EVDPoP) Study

External ventricular drain (EVD) placement and management pose risks to neurocritically ill patients. Yet, little is known about EVD management or hospital EVD management practices and policies in US hospitals. A narrative review was conducted to describe EVD-related publications reported in PubMed and Embase between 1953 and 2019, and a survey was used to examine US hospital EVD practices and policies, including adherence to EVD guideline recommendations. Overall, 912 relevant articles were published between 1953 and 2019 (average 21; range, 0 to 102 articles, per year), primarily related to indications for EVD placement (n=275, 30.2%), EVD-associated complications (n=206, 22.6%), and EVD care (n=200, 21.9%). The number of EVD publications increased over time (R2=0.7), and most publications addressed EVD-associated infection (n=296, 73.4%) and EVD insertion (n=195, 45.2%). Survey responses were received from 30 hospitals (37.5% response rate), and reported use of antimicrobial-impregnated catheters in 80% of hospitals, preinsertion antibiotic administration in 70%, collection of cerebrospinal fluid samples for suspicion of ventriculitis in 73.3%, tracking of EVD-associated infection in 86.7%, routine EVD clamping during transport in 66.7%, and monitoring of intracranial pressure during transport in 33.3%. Adherence to hospital policies was high for recommendations related to flushing an EVD and changing cerebrospinal fluid drainage systems (100% [range, 0% to 100%] each), but low for intrahospital transportation (16.7% [0% to 83.3%]), EVD removal (0% [0% to 66.7%]), patient and family education (0% [0% to 100%]), and administration of intraventricular medication (0% [0% to 100%]). In summary, the published literature related to EVD insertion and maintenance, and reported EVD hospital practices and policies, primarily focus on reducing EVD-associated infections. Still, overall adherence of hospital EVD policies to guideline recommendations is modest. To promote a culture of EVD safety, clinicians should focus on reducing all EVD-associated adverse events.

External Validation and Modification of Nationwide Inpatient Sample Subarachnoid Hemorrhage Severity Score

BACKGROUND

The Nationwide Inpatient Sample Subarachnoid Hemorrhage (SAH) Severity Score (NIS-SSS) was developed as a measure of SAH severity for use in administrative databases. The NIS-SSS consists of International Classification of Diseases Ninth Revision (ICD-9) diagnostic and procedure codes derived from the SAH inpatient course and has been validated against the Hunt-Hess score (HH).

OBJECTIVE

To externally validate both the NIS-SSS and a modified version of the NIS-SSS (m-NIS-SSS) consisting of codes present only on admission, against the HH in a Canadian province-wide registry and administrative database of SAH patients.

METHODS

A total of 1467 SAH patients admitted to Ontario stroke centers between 2003 and 2013 with recorded HH were included. The NIS-SSS and m-NIS-SSS were validated against the HH by testing correlation between the NIS-SSS/m-NIS-SSS and HH, comparing discriminative ability of the NIS-SSS/m-NIS-SSS vs HH for poor outcome by calculating area under the curve (AUC), and comparing calibration of the NIS-SSS, m-NIS-SSS, and HH by plotting predicted vs observed outcome.

RESULTS

Correlation with HH was 0.417 (P ≤ .001) for NIS-SSS, and 0.403 (P ≤ .001) for m-NIS-SSS. AUC for prediction of poor outcome was 0.786 (0.764-0.808) for HH, 0.771 (0.748-0.793) for NIS-SSS, and 0.744 (0.721-0.767) for m-NIS-SSS. Calibration plots demonstrated that HH had the most accurate prediction of outcome, whereas the NIS-SSS and m-NIS-SSS did not accurately predict low risk of poor outcome.

CONCLUSION

The NIS-SSS and m-NIS-SSS have good external validity, and therefore, may be suitable to approximate traditional clinical scores of disease severity in SAH research using administrative data.

Effect of a bundle approach on external ventricular drain-related infection

BACKGROUND

Emergency placement of an external ventricular drain (EVD) is one of the most frequently performed neurosurgical procedures. EVD-related infection continues to be a major challenge causing significant morbidity and costs. Bundle approaches have been shown to reduce infection rates; however, they are still not widely used, and observation periods often were rather short.

METHODS

The present study evaluated the effect of a multi-item bundle approach for EVD placement and care on the occurrence of EVD-related infection. A before/after approach was used to compare groups of consecutive patients over 5-year epochs to control for bias and secondary confounding variables.

RESULTS

The number of patients in the group before implementation of the bundle approach was 141 and 208 thereafter. There were no statistical differences in demographic and other variables. While 41/141 patients (29.1%) had an EVD-related infection before, this was the case in only 10/208 patients (4.8%) thereafter (p < 0.0001). The EVD-related infection rate was reduced from 13.7/1000 catheter days to 3.2/1000, and the 50% probability of an EVD-related infection in correlation to the mean duration of EVD placement was significantly lower (p < 0.0001). Routine EVD replacement was not helpful to reduce EVD-related infection. EVD-related infection rates remained low also over the next 8 years after the study was finished.

CONCLUSIONS

The introduction of a multi-item bundle approach for EVD insertion and care resulted in a marked reduction of EVD-related infection. Long observation periods over 5 years and beyond confirm that short-term changes are sustained with continued use of such protocols.

Brain-Relaxing Effect of Different Diuretic Regimens in Supratentorial Tumor Surgery: A Comparative Study Guided by Optic Nerve Sheath Diameter

Background:

Hyperosmolar therapy is a well-established method to approach brain relaxation during craniotomy. Mannitol is used with a wide range of dosing regimens, combination with loop diuretics exerts a synergistic effect resulting in both reduction of the dose and its complications. Ultrasound measurement of optic nerve sheath diameter (ONSD) gives reliable information about intracranial pressure (ICP) and avoids overdosing and complications of osmotherapy.

Aims and Objectives:

In this study, we compare the ordinary dose of mannitol with the low dose combined with furosemide and detect the effect on ICP by ONSD.

Setting and Design:

This is a prospective, randomized, double-blind study involving 60 patients undergoing supratentorial brain tumor surgery.

Materials and Methods:

Sixty patients were enrolled in this study, divided into two equal groups: Group M received mannitol 1 g.kg⁻¹: while Group F received mannitol 0.25 g.kg⁻¹ and furosemide 0.5 mg.kg⁻¹. Reduction in ONSD measurement was the primary objective, while brain-relaxation score (BRS), hemodynamic changes, urine output, serum lactate, and changes in serum electrolyte were the secondary objectives.

Statistical Analysis:

Data collected were analyzed using SPSS software, IBM, USA, version 22. P value was considered significant if <0.05.

Results:

ONSD and BRS showed no statistically significant difference between the studied groups. After diuresis, Group M showed significant reduction in heart rate and mean arterial blood pressure, serum sodium, potassium, and lactate (P = 0.02, P = 0.02, P = 0.001, P = 0.001, P = 0.001, P = 0.001 respectively), with increased urine output (UOP) and fluids replacement (P = 0.00, P = 0.01, respectively).

Conclusion:

Compared to high dose, adding loop diuretics to low-dose mannitol during supratentorial brain tumor surgeries resulted in comparable BRSs with a lower incidence of hemodynamic and metabolic disturbances.

Predictors of ventriculostomy infection in a large single-center cohort

OBJECTIVE

External ventricular drain (EVD) placement is a common neurosurgical procedure. While this procedure is simple and effective, infection is a major limiting factor. Factors predictive of infection reported in the literature are not conclusive. The aim of this retrospective, single-center large series was to assess the rate and independent predictors of ventriculostomy-associated infection (VAI).

METHODS

The authors performed a retrospective chart review of consecutive patients who underwent EVD placement between January 2012 and January 2018.

RESULTS

A total of 389 patients were included in the study. The infection rate was 3.1% (n = 12). Variables that were significantly associated with VAI were EVD replacement (OR 10, p = 0.001), bilateral EVDs (OR 9.2, p = 0.009), duration of EVD placement (OR 1.1, p = 0.011), increased CSF output/day (OR 1.0, p = 0.001), CSF leak (OR 12.9, p = 0.001), and increased length of hospital stay (OR 1.1, p = 0.002). Using multivariate logistic regression, independent predictors of VAI were female sex (OR 7.1, 95% CI 1.1-47.4; p = 0.043), EVD replacement (OR 8.5, 95% CI 1.44-50.72; p = 0.027), increased CSF output/day (OR 1.01, 95% CI 1.0-1.02; p = 0.023), and CSF leak (OR 15.1, 95% CI 2.6-87.1; p = 0.003).

CONCLUSIONS

The rate of VAI was 3.1%. Routine CSF collection (every other day or every 3 days) and CSF collection when needed were not associated with VAI. The authors recommend CSF collection when clinically needed rather than routinely.

Telemetric Intracranial Pressure Monitoring: A Systematic Review

Telemetric intracranial pressure (ICP) monitoring is a new method of measuring ICP which eliminates some of the shortcomings of previous methods. However, there are limited data on specific characteristics, including the advantages and disadvantages of this method. The main aim of this study was to demonstrate the indications, benefits, and complications of telemetric ICP monitoring. PubMed, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for relevant studies without language or date restriction in May 2019. Human studies in which telemetric ICP monitoring was the main subject of the study were included. Our initial search resulted in 1650 articles from which 50 studies were included. There were no randomized controlled trials. The majority of the studies were case reports or case series (68%). The most common aim of studies was testing of the device (52%), and monitoring the disease progression or recovery (46%). The most common indications for telemetric ICP monitoring in these studies were testing cerebrospinal fluid shunt function (46%), ICP control after the procedure (36%), and diagnosing intracranial hypertension (22%) and hydrocephalus (12%). In total, 1423 brain disease patients had been monitored in studies. The possibility of long-term ICP monitoring as the main benefit was reported in 38 (76%) studies. The associated complication rate was 7.1%. Despite the increasing application of telemetric monitoring devices, studies to evaluate specific characteristics of this method have been infrequent and inadequate. Future research using a higher level of scientific methods is needed to evaluate advantage and disadvantages.

Risk factors for meningitis in neurosurgical patients with cerebrospinal fluid drains: prospective observational cohort study

BACKGROUND

Cerebrospinal fluid (CSF) drainage or intracranial pressure (ICP) monitoring devices are life-saving devices. We examined the risk factors for infections related to them and assessed the effect of an infection control (IC) intervention.

METHODS

A prospective observational study was conducted in the Neurosurgical Department of our hospital between 2014 and 2017. We included all consecutive patients undergoing CSF catheter insertions, including external ventricular drainage (EVD), lumbar drainage (LD), and ICP catheters. An IC intervention was implemented between March and August 2016. We examined risk factors for meningitis or ventriculitis, defined according to Healthcare-associated infections surveillance definitions, on univariate and multivariate analysis.

RESULTS

A total of 232 patients with 437 drains (212 EVDs, 92 LDs, and 133 ICPs) were included. On univariate and multivariate analysis, the infection incidence was 13.7 per 1000 drain days (17.3/1000 before IC intervention, 7.9/1000 during, and 9.2/1000 after the intervention). Most episodes were caused by Gram-negative bacteria, and the most common pathogen was Acinetobacter baumanii. Risk factors for infection per patient included diabetes mellitus (p = 0.017), CSF leak (p = 0.032), drain opening (p = 0.027), and the duration of the drain in days (p = 0.035). Risk factors per catheter included drain opening (p < 0.001), drain days (p = 0.001), and the IC intervention period compared to before the intervention period (p = 0.037). When restricting the analysis to EVDs, drain days (p = 0.001) was the only significant risk factor.

CONCLUSIONS

Strict adherence to IC, shortening drain duration, and avoiding unnecessary opening and manipulation of the drains are crucial to preventing neurosurgical drain infections.

Complications of invasive intracranial pressure monitoring devices in neurocritical care

Intracranial pressure monitoring devices have become the standard of care for the management of patients with pathologies associated with intracranial hypertension. Given the importance of invasive intracranial monitoring devices in the modern neurointensive care setting, gaining a thorough understanding of the potential complications related to device placement-and misplacement-is crucial. The increased prevalence of intracranial pressure monitoring as a management tool for neurosurgical patients has led to the publication of a plethora of papers regarding their indications and complications. The authors aim to provide a concise review of key contemporary articles in the literature concerning important complications with the hope of elucidating practices that improve outcomes for neurocritically ill patients.