Prospective, multicentre study of external ventricular drainage-related infections in the UK and Ireland

Pathophysiology and Prevention of Ventriculostomy-Related Infections: A Review

This qualitative review aims to summarize current knowledge on ventriculostomy-related infection (VRI) pathophysiology and its prevention. VRI generally occurs at day 10, mainly because of Gram-positive cocci, after a cerebrospinal fluid leak. Skin microbiota and biofilm seem to play a major role in VRI pathogenesis. Colonization of external ventricular drain by biofilm is universal and occurs quickly after catheter insertion. However, pathogens from the skin are more often associated with VRI than commensal bacteria. A review of proposed preventive measures shows that none has proven to be fully efficient. Periprocedural and prolonged systemic prophylactic antimicrobials have not shown to prevent VRIs and may promote the emergence of more resistant or pathogenic strains. Antimicrobial and silver-impregnated external ventricular drains, although promising, have not demonstrated preventive effects and may modify bacterial ecology. These results are consistent with the proposed pathophysiology. Finally, we will present a few propositions for future research that may help in improving our knowledge and thus better prevent VRIs. Until then, given the available data, limiting the duration of ventricular drainage may be the most attainable option to prevent VRIs.

Development of an Evidence-based Care Bundle for Prevention of External Ventricular Drain-related Infection: Results of a Single-center Prospective Cohort Study and Literature Review

Background

External ventricular drain (EVD)-related infection (ERI) is a common complication in cranial neurosurgery practice with high mortality. The risk factors associated with ERI are not well studied in low- and middle-income countries (LMIC) like India. Identifying the risk variables is a necessity to design robust evidence-based care bundles for ERI prevention.

Materials and methods

This is a single-center prospective cohort study. Patients with and without ERI during the 2-year study period were analyzed along with literature review to identify the risk variables associated with ERI. The Institute for Healthcare Improvement (IHI) comprehensive flowchart was used to develop the concept care bundle for ERI prevention.

Results

A total of 211 EVD were inserted during the study period. 15 ERI (7.1%) were identified based on IDSA criteria, with an average infection rate of 11.12 per 1000 EVD days. Gram negative bacteria (GNB) were the predominant pathogen (12/15, 80%), with Klebsiella pneumoniae (6/15, 40%) being the most common bacteria isolated. In multivariate analysis, the risk variables associated with ERI were use of broad spectrum pre-surgical antimicrobial prophylaxis for long duration, choice of posterior craniometric points for EVD insertion, EVD duration >7 days, EVD leak and surveillance cerebrospinal fluid (CSF) sampling at periodic intervals. Based on the risk variables identified in this study and literature review, a consensus decision on the care elements for the insertion and maintenance phases was chosen for the concept care bundle for ERI prevention.

Conclusion

An evidence-based concept care bundle for ERI prevention is proposed for further multicentric evaluation and validation.

How to cite this article

Ponnambath DK, Divakar G, Mamachan J, Biju S, Raja K, Abraham M. Development of an Evidence-based Care Bundle for Prevention of External Ventricular Drain-related Infection: Results of a Single-center Prospective Cohort Study and Literature Review. Indian J Crit Care Med 2024;28(8):760-768.

Risk Factors for Central Nervous System Infections After Craniotomy

The central nervous system (CNS) is less prone to infection owing to protection from the brain-blood barrier. However, craniotomy destroys this protection and increases the risk of infection in the brain of patients who have undergone craniotomy. CNS infection after craniotomy significantly increases the patient's mortality rate and disability. Controlling the occurrence of intracranial infection is very important for post-craniotomy patients. CNS infection after craniotomy is caused by several factors such as preoperative, intraoperative, and post-operative factors. Craniotomy may lead to postsurgical intracranial infection, which is mainly associated with surgery duration, infratentorial (posterior fossa) surgery, cerebrospinal fluid leakage, drainage tube placement, unregulated use of antibiotics, glucocorticoid use, age, diabetes, and other systemic infections. Understanding the risk factors of CNS infection after craniotomy can benefit reducing the incidence of intracranial infectious diseases. This will also provide the necessary guidance and evidence in clinical practice for planning to control intracranial infection in patients with craniotomy.

The pharmacokinetics/pharmacodynamics of ceftazidime/avibactam for central nervous system infections caused by carbapenem-resistant Gram-negatives: a prospective study

OBJECTIVES

To describe the pharmacokinetics/pharmacodynamics (PK/PD) of ceftazidime/avibactam in critically ill patients with CNS infections.

METHODS

A prospective study of critically ill patients with CNS infections who were treated with ceftazidime/avibactam and the steady-state concentration (Css) of ceftazidime/avibactam in serum and/or CSF was conducted between August 2020 and May 2023. The relationship between PK/PD goal achievement, microbial eradication and the clinical efficacy of ceftazidime/avibactam was evaluated.

RESULTS

Seven patients were finally included. The ceftazidime/avibactam target attainment in plasma was optimal for three, quasi-optimal for one and suboptimal for three. In three patients with CSF drug concentrations measured, ceftazidime/avibactam target attainment in CSF was 100% (3/3), which was optimal. The AUCCSF/serum values were 0.59, 0.44 and 0.35 for ceftazidime and 0.57, 0.53 and 0.51 for avibactam. Of the seven patients, 100% (7/7) were treated effectively, 71.4% (5/7) achieved microbiological eradication, 85.7% (6/7) survived and 14.3% (1/7) did not survive.

CONCLUSIONS

The limited clinical data suggest that ceftazidime/avibactam is effective in the treatment of CNS infections caused by MDR Gram-negative bacilli (MDR-GNB), can achieve the ideal drug concentration of CSF, and has good blood-brain barrier penetration.

Epidemiology, clinical profile, and outcomes of CSF-diversion catheter-related infections - Prospective cohort study results from a single quaternary neurosurgery referral centre

BACKGROUND

Device-associated CNS infections is a major subgroup of healthcare associated CNS infections. Healthcare-associated ventriculitis or meningitis differs considerably from community-acquired meningitis in its epidemiology, pathogenesis, clinical presentation and management.

OBJECTIVES

This study aimed to identify the infection rates, the associated risk factors, and outcomes of these life-threatening infections.

METHODS

This was a 2-year single center prospective cohort study. Patient's clinical data, laboratory parameters, treatment and their outcomes were collected using data collection tool, and device days were collected from the hospital information system (HIS). Patients were categorised using IDSA criteria as contamination or colonisation or infection. Cox regression model was used for multivariate analysis to estimate hazard risk.

RESULTS

A total of 578 CSF diversion catheters were inserted in 472 patients. The average rate for EVD and LD infection were 11.12 and 11.86 per 1000 device days respectively. The average infection rates for VP and LP shunts were 6% and 5.2% per procedure, respectively. The commonest etiological agent causing CSF diversion catheter-related infection (CDRI) was Klebsiella pneumoniae (n = 14, 40%). The risk factors which were independently associated with increased infection risk by cox regression analysis were drain insertion ≥7 days [HR:11.73, p -0.03], posterior approach of EVD insertion (occipital) [HR:9.53, p - 0.01], pre-OP ASA score>3 [HR:8.28, p - 0.013] presence of EVD/LD leak [HR: 17.24, p < 0.0001], male gender [HR:2.05, p-0.05] and presence of associated peri-operative scalp infections [HR:3.531, p-0.005]. Shift to narrow spectrum surgical prophylactic antibiotic [Coefficient: -1.284, p-0.03] and reduction in CSF sampling frequency [Coefficient: -1.741, p-0.02] were found to be negatively associated with CDRI.

CONCLUSIONS

The study demonstrated drain insertion ≥7 days, posterior approach of EVD insertion, presence of EVD/LD leak, male gender and presence of associated peri-operative scalp skin and soft tissue infections were associated with increased risk of infection.

Impact of Subarachnoid Hemorrhage in Ventriculostomy-Related Infections Prospective Comparison of Two Neurosurgical Injury Contexts

BACKGROUND

Long thought to be immune privileged, the central nervous system is far from being devoid of local immunity. Subarachnoid hemorrhage (SAH) and traumatic brain injury represent 2 distinct central nervous system injury situations which, while both exposed to external ventricular drains, present different incidences of ventriculostomy-related infection (VRI). We sought to compare VRI incidence and initial cerebrospinal fluid (CSF) inflammatory profiles in these 2 clinical situations.

METHODS

From 2015 to 2020, 227 patients treated for SAH (193) or traumatic brain injury (34) with an external ventricular drain were prospectively included. CSF samples were sent daily for microbiological examination, cell count, and biochemical analysis. VRI was defined as a positive CSF culture associated with CSF profile modifications and clinical signs. Ventriculostomy-related colonization was defined as positive catheter culture at removal. Positive events were defined as VRI and/or ventriculostomy-related colonization.

RESULTS

Eleven patients suffered from VRI, with an incidence of 3.6 VRI per 1000 catheter-days. All VRIs occurred among SAH patients without a significant difference. Median duration of drainage was 12 (7-18) days, there were no significant differences for known VRI risk factors. Positive events were significantly higher in SAH patients (20.7% vs. 2.9%, P = 0.013). Inflammatory CSF markers and serum white blood cells were higher in SAH patients.

CONCLUSIONS

Local inflammatory markers were markedly higher in SAH than in traumatic brain injury. However, positive events were more frequent in SAH. Furthermore, SAH may be a risk factor for VRI. Hypothesis that a primary injury to the subarachnoid space could impair central nervous system immune functions should be explored.

Significant Reduction in External Ventricular Drain-Related Infections After Introducing a Novel Bundle Protocol: A Before and After Trial

BACKGROUND

External ventricular drain (EVD)-related infection (ERI) is a serious complication in neurosurgical patients. The estimated ERI rates range from 5 to 20 cases per 1,000 EVD catheter days. The pathophysiology of ERI is similar to central line-associated bloodstream infections (CLABSIs) stemming from skin-derived bacterial colonization. The use of bundle management can reduce CLABSI rates. Due to the pathogenic similarities between infections related to the two devices, we developed and evaluated the effectiveness of an ERI-bundle protocol based on CLABSI bundles.

METHODS

From November 2016 to November 2021, we conducted a study to evaluate the effectiveness of an ERI-bundle protocol. This study adopted a before-and-after trial, comparing the ERI rates for the 2 years before and 3 years after the introduction of the newly developed ERI-bundle protocol. We also analyzed the contributing factors to ERI using logistic regression analysis.

RESULTS

A total of 183 patients with 2,381 days of catheter use were analyzed. The ERI rate decreased significantly after the ERI-bundle protocol from 16.7% (14 of 84; 14.35 per 1,000 catheter days) to 4.0% (4 of 99; 3.21 per 1,000 catheter days) (P = 0.004).

CONCLUSION

Introduction of the ERI-bundle protocol was very effective in reducing ERI.

Construction and validation of infection risk model for patients with external ventricular drainage: a multicenter retrospective study

PURPOSE

External ventricular drainage (EVD) is a life-saving neurosurgical procedure, of which the most concerning complication is EVD-related infection (ERI). We aimed to construct and validate an ERI risk model and establish a monographic chart.

METHODS

We retrospectively analyzed the adult EVD patients in four medical centers and split the data into a training and a validation set. We selected features via single-factor logistic regression and trained the ERI risk model using multi-factor logistic regression. We further evaluated the model discrimination, calibration, and clinical usefulness, with internal and external validation to assess the reproducibility and generalizability. We finally visualized the model as a nomogram and created an online calculator (dynamic nomogram).

RESULTS

Our research enrolled 439 EVD patients and found 75 cases (17.1%) had ERI. Diabetes, drainage duration, site leakage, and other infections were independent risk factors that we used to fit the ERI risk model. The area under the receiver operating characteristic curve (AUC) and the Brier score of the model were 0.758 and 0.118, and these indicators' values were similar when internally validated. In external validation, the model discrimination had a moderate decline, of which the AUC was 0.720. However, the Brier score was 0.114, suggesting no degradation in overall performance. Spiegelhalter's Z-test indicated that the model had adequate calibration when validated internally or externally (P = 0.464 vs. P = 0.612). The model was transformed into a nomogram with an online calculator built, which is available through the website: https://wang-cdutcm.shinyapps.io/DynNomapp/ .

CONCLUSIONS

The present study developed an infection risk model for EVD patients, which is freely accessible and may serve as a simple decision tool in the clinic.

Prospective Comparative Study of External Ventricular Drain Catheter Colonization: Antibiotic-Impregnated versus Conventional Drains

OBJECTIVE

Our aim was to compare the prevalence of biofilm formation on antibiotic-impregnated (AIC) versus standard (SC) external ventricular drain (EVD) catheters.

METHODS

From March 2018 to November 2020, all consecutive EVD catheters inserted in adult patients were included. After removal, EVD catheters were analyzed under scanning electronic microscopy, on both extraluminal and intraluminal faces. Standard culture of catheter tips was also performed.

RESULTS

Overall, 114 catheters were included in 101 patients. There were 48 AICs and 66 SCs. Standard culture showed that ventriculostomy-related colonization was more frequent in SC than in AIC (26 vs. 10%; P = 0.06). Gram-negative rods accounted for 25% of ventriculostomy-related colonization in AICs, and none was documented in SCs. Scanning electronic microscopy observation showed mature biofilm on more than 80% of catheters, without significant difference between catheter type. Also, there was no difference between extraluminal and intraluminal colonization rate. There were 2 ventriculostomy-related infections in each group (5% and 3% among AICs and SCs respectively; P = 1).

CONCLUSIONS

Mature biofilm presence on the intraluminal and the extraluminal faces is similar on AICs and SCs. Accordingly, AICs do not seem to efficiently prevent biofilm formation on EVD catheters. The impact of AICs on the microbiological epidemiology of colonizing biofilm should be further evaluated.

Rapid Versus Gradual Weaning of External Ventricular Drain: A Systematic Literature Review and Meta-analysis

The insertion of an external ventricular drain (EVD) is one of the most common neurosurgical procedures. Whether the weaning method (gradual or rapid) influences the ventriculoperitoneal shunt (VPS) insertion rate has not been conclusively established. The aim of this study is to provide a systematic literature review and conduct a meta-analysis of studies comparing gradual with rapid EVD weaning regarding VPS insertion rate. Articles were identified by searching the Pubmed/Medline, Embase, and Web of Science databases throughout October 2022. Two independent researchers assessed the studies for inclusion and quality. We included randomized trials, prospective cohort studies, and retrospective cohort studies, which compared gradual and rapid EVD weaning. The primary outcome was VPS insertion rate, whereas secondary outcomes were EVD-associated infection (EVDAI) rate and length of stay in the hospital and intensive care unit (ICU). Four studies directly comparing rapid versus gradual EVD weaning, with 1337 patients suffering from subarachnoid hemorrhage, were identified and included in the meta-analysis. VPS insertion rate was 28.1% and 32.1% in patients with gradual and rapid EVD weaning, respectively (relative risk 0.85, 95% confidence interval 0.49-1.46, p = 0.56). Further, the EVDAI rate was comparable between the groups (gradual group 11.2%, rapid group 11.5%, relative risk 0.67, 95% confidence interval 0.24-1.89, p = 0.45), whereas length of stay in the ICU and hospital were significantly shorter in the rapid weaning group (2.7 and 3.6 days, respectively; p < 0.01). Rapid EVD weaning seems comparable to gradual EVD weaning concerning VPS insertion rates and EVDAI, whereas hospital and ICU length of stay is significantly reduced.

External ventriculostomy-associated infection reduction after updating a care bundle

BACKGROUND

Despite the clinical benefits of external ventricular drains (EVD), these devices can lead to EVD-related infections (EVDRI). The drainage insertion technique and standardized guidelines can significantly reduce the risk of infection, mainly caused by gram-positive bacteria. However, gram-negative microorganisms are the most frequent causative microorganisms of EVDRI in our hospital. We aimed to determine whether a new bundle of measures for the insertion and maintenance of a drain could reduce the incidence of EVDRI. This cohort study of consecutive patients requiring EVD from 01/01/2015 to 12/31/2018 compared the patients' characteristics before and after introducing an updated protocol (UP) for EVD insertion and maintenance in 2017.

RESULTS

From 204 consecutive patients, 198 requiring EVD insertion were included (54% females, mean age 55 ± 15 years). The before-UP protocol included 87 patients, and the after-UP protocol included 111 patients. Subarachnoid (42%) and intracerebral (24%) hemorrhage were the main diagnoses at admission. The incidence of EVDRI fell from 13.4 to 2.5 episodes per 1000 days of catheter use. Gram-negative bacteria were the most frequent causative microorganisms. Previous craniotomy remained the only independent risk factor for EVDRI. EVDRI patients had increased mechanical ventilation durations, hospital and ICU stays, and percutaneous tracheostomy requirements.

CONCLUSIONS

A care bundle focusing on fewer catheter sampling and more accurate antiseptic measures can significantly decrease the incidence of EVDRI. After implementing the management protocol, a decreased incidence of infections caused by gram-negative and gram-positive bacteria and reduced ICU and hospital lengths of stay were observed.

Treatment of Ventriculitis and Meningitis After Neurosurgery Caused by Carbapenem-Resistant Enterobacteriaceae (CRE): A Challenging Topic

Post-neurosurgical infection is a common complication of neurosurgery, and serious infection can threaten the life of patients. In recent years, the increase in multidrug-resistant bacteria, especially carbapenem-resistant Enterobacteriaceae (CRE), has proved fatal to patients. Although there are a few cases of CRE meningitis and few clinical trials have been carried out, it has attracted increasing attention with the increasing probability of its occurrence, especially considering that there are few successful cases. An increasing number of studies are also looking for the risk factors and clinical symptoms of CRE intracranial infection. In terms of treatment, some new antibiotics are gradually being used in the clinic, but due to the complicated drug-resistant mechanism of CRE and the obstruction of the blood‒brain barrier (BBB), the therapeutic effect is still very poor. In addition, obstructive hydrocephalus and brain abscess caused by CRE meningitis are still important causes of patient death and are also difficult to treat.

Intracranial Myroides odoratimimus Infection After EVD Successfully Treated with Intravenous Plus Intraventricular Tigecycline: A Case Report

Intracranial infections are the most serious and common postoperative complications with significant mortality and morbidity. Myroides odoratimimus (M. odoratimimus), a Gram-negative environmental species and an opportunistic microorganism, predominantly infects immunocompromised individuals. Limited clinical experiences and documented multidrug resistance have resulted in a scarcity of data on the treatment of M. odoratimimus infections. As far as we know, this is the first reported case of an intracranial M. odoratimimus infection with external ventricular drains (EVD) that was effectively treated with a combination of intravenous and intraventricular tigecycline in an immunocompetent adult host.

Prevention of Ventriculostomy Related Infection: Effectiveness of Impregnated Biomaterial

External ventricular drain(EVD) exposes the patient to infectious complications which are associated with significant morbidity and economic burden. Biomaterials impregnated with various antimicrobial agents have been developed to decrease the rate of bacterial colonization and subsequent infection. While promising, antibiotics and silver-impregnated EVD showed conflicting clinical results. The aim of the present review is to discuss the challenges associated with the development of antimicrobial EVD catheters and their effectiveness from the bench to the bedside.

Prevention of device-related infections in patients with cancer: Current practice and future horizons

Over the past several years, multifaceted advances in the management of cancer have led to a significant improvement in survival rates. Throughout patients' oncological journeys, they will likely receive one or more implantable devices for the administration of fluids and medications as well as management of various comorbidities and complications related to cancer therapy. Infections associated with these devices are frequent and complex, often necessitating device removal, increasing health care costs, negatively affecting quality of life, and complicating oncological care, usually leading to delays in further life-saving cancer therapy. Herein, the authors comprehensively review multiple evidence-based recommendations along with best practices, expert opinions, and novel approaches for the prevention of diverse device-related infections. The authors present many general principles for the prevention of these infections followed by specific device-related recommendations in a systematic manner. The continuous involvement and meaningful cooperation between regulatory entities, industry, specialty medical societies, hospitals, and infection control-targeted interventions, along with primary care and consulting health care providers, are all vital for the sustained reduction in the incidence of these preventable infections.

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.

Comparison of Two Drainage Systems on Chronic Subdural Hematoma Recurrence

BACKGROUND

 Chronic subdural hematoma (CSDH) is a common type of intracranial hemorrhage, especially among the elderly, with a recurrence rate as high as 33%. Little is known about the best type of drainage system and its relationship with recurrence. In this study, we compare the use of two drainage systems on the recurrence rate of CSDH.

METHODS

 We retrospectively analyzed the charts of 172 CSDH patients treated with bedside twist drill craniostomy (TDC) and subdural drain insertion. Patients were divided into two groups: group A (n = 123) received a pediatric size nasogastric tube [NGT]), whereas group B (n = 49) had a drain commonly used for external ventricular drainage (EVD). Various demographic and radiologic data were collected. Our main outcome was recurrence, defined as symptomatic re-accumulation of hematoma on the previously operated side within 3 months.

RESULTS

 In all, 212 cases of CSDH were treated in 172 patients. The majority of patients were male (78%) and had a history of previous head trauma (73%). Seventeen cases had recurrence, 11 in group A and 6 in group B. The use of antiplatelet and anticoagulation agents was associated with recurrence (p = 0.038 and 0.05, respectively). There was no difference between both groups in terms of recurrence (odds ratio [OR] = 1.42; 95% confidence interval [CI]: 0.49-4.08; p = 0.573).

CONCLUSION

 CSDH is a common disease with a high rate of recurrence. Although using a drain postoperatively has shown to reduce the incidence of recurrence, little is known about the best type of drain to use. Our analysis showed no difference in the recurrence rate between using the pediatric size NGT and the EVD catheter post-TDC.

CNS infection in children with brain tumors: adding ventriculostomy to brain tumor resection increases risk more than 20-fold

PURPOSE

To investigate the risk of central nervous system (CNS) infections in children undergoing neurosurgery for brain tumors.

METHODS

Single-center retrospective cohort study including all children with brain tumors undergoing neurosurgical treatment over an 11-year period.

RESULTS

A total of 274 patients undergoing 733 neurosurgical procedures were included. Overall, 12.8% of patients were diagnosed with a CNS infection during their course of treatment. CNS infections were more frequent among children treated with CSF diversion (p < 0.001) and independently associated with low age (OR/y 0.9 (CI 95% 0.769-0.941), intraventricular (OR 2.8, CI 95% 1.2-6.5), and high-grade tumors (OR 2.7, CI 95% 1.1-6.5). The majority of CNS infections occurred within 30 days of surgery, resulting in a postoperative CNS infection rate of 5.3%. Postoperative CNS infections were significantly more frequent following adjunct EVD placement during tumor resection compared to a stand-alone craniotomy (30.4% vs. 1.5%, RR 20.6, CI 95% 5.7-72.2).

CONCLUSION

CNS infections affect at least 12% of children with brain tumors and are associated with age, tumor location, and grade. Adding EVD to tumor surgery increases the risk of postoperative CNS infection, and reconsidering routine adjunct EVD placement is therefore advocated.

External Ventricular Drainage: A Practical Guide for Neuro-Anesthesiologists

External ventricular drainage is often considered a life-saving treatment in acute hydrocephalus. Given the large number of discussion points, the ideal management of EVD has not been completely clarified. The objective of this study was to review the most relevant scientific evidence about the management of EVD in its main clinical scenarios. We reviewed the most recent and relevant articles about indications, timing, management, and complications of EVD in neurocritical care, with particular interest in patients with subarachnoid hemorrhage (SAH), severe traumatic brain injury (TBI), and intraventricular hemorrhage (IVH) using the following keywords alone or matching with one another: intracranial pressure, subarachnoid hemorrhage, traumatic brain injury, intraventricular hemorrhage, external ventricular drainage, cerebrospinal shunt, intracranial pressure monitoring, and ventriculoperitoneal shunt. In the management of EVD in SAH, the intermittent drainage strategy is burdened with an elevated risk of complications (e.g., clogged catheter, hemorrhage, and need for replacement). There seems to be more ventriculoperitoneal shunt dependency in rapid weaning approach-managed patients than in those treated with the gradual weaning approach. Although there is no evidence in favor of either strategy, it is conventionally accepted to adopt a continuous drainage approach in TBI patients. Less scientific evidence is available in the literature regarding the management of EVD in patients with severe TBI and intraparenchymal/intraventricular hemorrhage. EVD placement is a necessary treatment in several clinical scenarios. However, further randomized clinical trials are needed to clarify precisely how EVD should be managed in different clinical scenarios.

Adverse financial and clinical burden of the use of prophylactic antibiotics in neurosurgical patients

Background

Current guidance does not support the administration of prophylactic antibiotics in non-infected post-operative surgical cases including neurosurgery.

Materials and methods

This paper is a qualitative assessment, highlighting the economic cost of excessive antimicrobial prescription and the healthcare costs of the extra days of admission in hospital.

Results

One hundred and one neurosurgical cases were analysed in a single institution over a one-year period. The additional course of post-operative antibiotics has a cost of £56.72 and receiving prolonged post-operative antibiotics added on average £1121.10 to their admission bill. Up to 13.4 patients may have experienced an adverse drug event.

Conclusion

This paper reinforces the adherence to guidelines can aid in the reduction of adverse drug events, improve patient outcomes, and reduce costs associated with unnecessary drug prescriptions and administration.

External Ventricular Drains: Development and Evaluation of a Nursing Clinical Practice Guideline

External ventricular drains (EVDs) are common in intensive care for neurocritical patients affected by different illnesses. Nurses play an essential role to ensure safe care, and guidelines are tools to implement evidence-based care. Thus, the aim of this study was to develop and evaluate the quality of a clinical guideline for critically ill patients with EVDs. Methodological research was conducted. The guideline development was based on a scoping review about nursing care to patients with EVDs. The guideline evaluation occurred in two phases: evaluation of its methodological rigor, with application of the Appraisal of Guidelines Research and Evaluation II to four experts on guidelines evaluation; and the Delphi technique, with a panel of nine specialists in neurocritical care, performed in two rounds. Data were analyzed by descriptive statistics and content validity ratio. In the first phase of the evaluation, three domains did not reach consensus, being reformulated. The second phase was conducted in two rounds, with nine and eight participants respectively, with 13 recommendations being reformulated and reassessed between rounds, inclusion of an EVD weaning category, and two flowcharts on patient's transport and mobility. Therefore, the guideline can be incorporated into nursing care practices. Further studies are necessary to assess its impact on clinical practice.

Management and safety of intraoperative ventriculostomy during early surgery for ruptured intracranial aneurysms

BACKGROUND

Brain edema and/or acute hydrocephalus are common features that limit working space during early surgery of aneurysmal subarachnoid hemorrhage (aSAH). Intraoperative ventriculostomy offers an immediate brain relaxation. However, management and complications related to the routine use of intraoperative external ventricular drainage (iEVD) are not well investigated.

METHODS

We retrospectively reviewed all patients who were treated with pterional craniotomy and clipping for ruptured anterior circulation aneurysms in our center between 2012 and 2019. We included in this study all patients submitted to iEVD using the Paine's point on the side of craniotomy. Indication for positioning of an iEVD was given in all cases whenever initial cisternal dissection was hampered by the lack of cerebrospinal fluid (CSF) circulation due to SAH and/or hydrocephalus.

RESULTS

In the study period, 162 patients with aSAH underwent surgical clipping. In 103 patients, an iEVD was used. The overall rate of iEVD-related complications was 6.7%, including 3 cases of catheter misplacement, one case of catheter obstruction, one case of related hemorrhage, and 2 cases of infection. The rate of shunt-dependent hydrocephalus was 16.5% (17/103 patients).

CONCLUSION

In our experience, iEVD is a safe technique that facilitates dissection during early surgery for intracranial ruptured aneurysms, without requiring an additional burr hole procedure.

The HeMoVal study protocol: a prospective international multicenter cohort study to validate cerebrospinal fluid hemoglobin as a monitoring biomarker for aneurysmal subarachnoid hemorrhage related secondary brain injury

INTRODUCTION

Preclinical studies provided a strong rationale for a pathophysiological link between cell-free hemoglobin in the cerebrospinal fluid (CSF-Hb) and secondary brain injury after subarachnoid hemorrhage (SAH-SBI). In a single-center prospective observational clinical study, external ventricular drain (EVD) based CSF-Hb proved to be a promising biomarker to monitor for SAH-SBI. The primary objective of the HeMoVal study is to prospectively validate the association between EVD based CSF-Hb and SAH-SBI during the first 14 days post-SAH. Secondary objectives include the assessment of the discrimination ability of EVD based CSF-Hb for SAH-SBI and the definition of a clinically relevant range of EVD based CSF-Hb toxicity. In addition, lumbar drain (LD) based CSF-Hb will be assessed for its association with and discrimination ability for SAH-SBI.

METHODS

HeMoVal is a prospective international multicenter observational cohort study. Adult patients admitted with aneurysmal subarachnoid hemorrhage (aSAH) are eligible. While all patients with aSAH are included, we target a sample size of 250 patients with EVD within the first 14 day after aSAH. Epidemiologic and disease-specific baseline measures are assessed at the time of study inclusion. In patients with EVD or LD, each day during the first 14 days post-SAH, 2 ml of CSF will be sampled in the morning, followed by assessment of the patients for SAH-SBI, co-interventions, and complications in the afternoon. After 3 months, a clinical follow-up will be performed. For statistical analysis, the cohort will be stratified into an EVD, LD and full cohort. The primary analysis will quantify the strength of association between EVD based CSF-Hb and SAH-SBI in the EVD cohort based on a generalized additive model. Secondary analyses include the strength of association between LD based CSF-Hb and SAH-SBI in the LD cohort based on a generalized additive model, as well as the discrimination ability of CSF-Hb for SAH-SBI based on receiver operating characteristic (ROC) analyses.

DISCUSSION

We hypothesize that this study will validate the value of CSF-Hb as a biomarker to monitor for SAH-SBI. In addition, the results of this study will provide the potential base to define an intervention threshold for future studies targeting CSF-Hb toxicity after aSAH.

STUDY REGISTRATION

ClinicalTrials.gov Identifier NCT04998370 . Date of registration: August 10, 2021.

Diagnostic Accuracy of Clinical Signs and Biochemical Parameters for External Ventricular Cerebrospinal Fluid Catheter-Associated Infection

Background and Objectives

Few prospective well-designed diagnostic accuracy studies have been performed to study the parameters of infection in patients suspected for external ventricular catheter-associated infection. Our objective was to analyze the diagnostic accuracy of clinical characteristics and biochemical and microbiological parameters in diagnosing external ventricular CSF catheter-associated infection.

Methods

From 2014 to 2017, we performed a single-center cohort study in consecutive patients at the intensive care unit who required an external ventricular CSF catheter in the Hague, the Netherlands. CSF was sampled and analyzed daily. Ventricular catheter-associated infection was defined according to the 2017 Infectious Diseases Society of America's Clinical Practice Guidelines. We compared clinical characteristics and biochemical parameters between patients with and without infection from 3 days before to 3 days after the day the CSF sample was collected that grew bacteria.

Results

A total of 103 patients were included of whom 15 developed a catheter-associated infection (15%). The median day cultures were positive was 3 days after CSF collection (interquartile range [IQR] +2 to +4). On day 0, none of the tests could differentiate between patients with and without infection. The CSF leukocyte count was increased in patients with ventricular catheter-associated infection as compared with patients without on days +2 and +3. The difference was most prominent on day +2 (1,703 × 10⁶/L [IQR 480–6,296] vs 80 × 10⁶/L [IQR 27–251]; p < 0.001; area under the curve [AUC] 0.87 [95% confidence interval (CI) 0.71–1.00]). Sensitivity for the CSF leukocyte count at a cutoff level >1,000 × 10⁶/L was 67% (95% CI 30–93), and specificity was 100% (95% CI 90–100); the positive predictive value was 100%, and the negative predictive value was 92% (95% CI 83–97). The percentage of polymorphonuclear cells (PMNs) was higher in patients with infection on days +1 and +2 (day +2 89% [IQR 78–94] vs 59% [IQR 39–75]; p < 0.01; AUC 0.91 [95% CI 0.81–1.0]).

Discussion

An elevated CSF leukocyte count and increased percentage of PMNs are the strongest indicators for external catheter-associated infections on the days before culture positivity. New CSF markers of drain-associated infection should be studied to enable earlier diagnosis and treatment in patients with an infection and reduce antibiotic treatment in those with no infection.

Classification of Evidence

This study provides Class I evidence that in individuals requiring an external ventricular CSF catheter, an elevated CSF leukocyte count and an increased percentage of PMNs are the strongest indicators of catheter-associated infections in the days before CSF culture positivity.

Risk Prediction of Central Nervous System Infection Secondary to Intraventricular Drainage in Patients with Intracerebral Hemorrhage: Development and Evaluation of a New Predictive Model Nomogram

BACKGROUND

Currently no reliable tools are available for predicting the risk of central nervous system (CNS) infections in patients with intracerebral hemorrhage after undergoing ventriculostomy drainage. The current study sought to develop and validate a nomogram to identify high-risk factors of CNS infection after ventriculomegaly drain placement for intracerebral hemorrhage.

METHODS

A total of 185 patients with intracerebral hemorrhage who underwent ventriculoperitoneal drainage were enrolled to the current study. Patients were divided into a CNS infection group (20 patients) and a non-CNS infection group (165 patients). The baseline data from both groups was used to develop and evaluate a model for predicting the likelihood of developing CNS infection after ventriculoperitoneal drain placement for intracerebral hemorrhage.

RESULTS

The finding showed that operative time, intraventricular drainage duration, postoperative temperature, white blood cell count in cerebrospinal fluid (CSF), neutrophils ratio in CSF, Red blood cell count in CSF, and glucose content in CSF were correlated with CNS infection. A nomogram for predicting the risk of CNS infection was constructed based on these variables. The c-index and the AUC of the ROC curve was 0.961, showing good discrimination. Clinical decision curve analysis indicated that the nomogram clinical application ranged between 1 and 100%. The clinical impact curve was generated to set with a threshold probability of 0.5.

CONCLUSION

The nomogram reported in the current study can be used by clinicians to identify patients likely to have secondary CNS infections, so that clinicians can better treat these patients at earlier stages.

A nationwide prospective multicenter study of external ventricular drainage: accuracy, safety, and related complications

OBJECTIVE

External ventricular drainage (EVD) catheters are associated with complications such as EVD catheter infection (ECI), intracranial hemorrhage (ICH), and suboptimal placement. The aim of this study was to investigate the rates of EVD catheter complications and their associated risk factor profiles in order to optimize the safety and accuracy of catheter insertion.

METHODS

A total of 348 patients with urgently placed EVD catheters were included as a part of a prospective multicenter observational cohort. Strict definitions were applied for each complication category.

RESULTS

The rates of misplacement, ECI/ventriculitis, and ICH were 38.6%, 12.2%, and 9.2%, respectively. Catheter misplacement was associated with midline shift (p = 0.002), operator experience (p = 0.031), and intracranial length (p < 0.001). Although mostly asymptomatic, ICH occurred more often in patients receiving prophylactic low-molecular-weight heparin (LMWH) (p = 0.002) and those who required catheter replacement (p = 0.026). Infectious complications (ECI/ventriculitis and suspected ECI) occurred more commonly in patients whose catheters were inserted at the bedside (p = 0.004) and those with smaller incisions (≤ 1 cm) (p < 0.001). ECI/ventriculitis was not associated with preinsertion antibiotic prophylaxis (p = 0.421), catheter replacement (p = 0.118), and catheter tunneling length (p = 0.782).

CONCLUSIONS

EVD-associated complications are common. These results suggest that the operating room setting can help reduce the risk of infection, but not the use of preoperative antibiotic prophylaxis. Although EVD-related ICH was associated with LMWH prophylaxis for deep vein thrombosis, there were no significant clinical manifestations in the majority of patients. Catheter misplacement was associated with operator level of training and midline shift. Information from this multicenter prospective cohort can be utilized to increase the safety profile of this common neurosurgical procedure.

Challenges and Controversies in the Management of Tuberculous Meningitis with Hydrocephalus: A Systematic Review and Sarawak Institution's Experience

Introduction To date, there are no standard practice guidelines available and no universal consensus regarding treatment protocol in management of tuberculous meningitis (TBM) with hydrocephalus. Over the years, diverse views have existed in neurosurgical management of TBM with hydrocephalus. Some authors advocate ventriculo-peritoneal (VP) shunt, while others suggest that external ventricular drainage (EVD) may be the preferable neurosurgical procedure for a poor-grade patient.

Method We systematically reviewed published literature and presented our institution's experience. We performed a retrospective case study in our Sarawak neurosurgical center from 2018 to 2020. We tabulated the outcome according to preoperative classifications, which were Vellore Grading (VG), Modified Vellore Grading (MVG), British Medical Research Council Classification (MRC), and others: author-defined.

Result In our center, there were 20 cases of TBM with hydrocephalus treated by EVD and VP shunt from 2018 to 2020. We systematically searched published medical literature, and 23 articles were retrieved and analyzed. Poor outcomes were observed in poor-grade patients, especially VG/MVG 3/4 and MRC 3, from both institution and systemic review data. Shunt complication rate was lower in our center as compared with published literature.

Conclusion Unfortunately, morbidity and mortality were approximately twofold higher in poor-grade as compared with good-grade patients. However, about one-third of poor-grade patients achieved a good outcome. Cerebrospinal fluid (CSF) diversion would be an unavoidable treatment for hydrocephalus. Poor-grade patients tend to have cerebral infarcts in addition to hydrocephalus. An extended duration of EVD placement could be a potential measure to assess Glasgow coma scale recovery and monitor serial CSF samples.

Delivering Large-Scale Neurosurgical Studies in the UK: The Impact of Trainees

The UK neurosurgical community has a track record of delivering high-quality, practice-changing clinical research studies, facilitated by a robust clinical research infrastructure and close collaborations between neurosurgical centers. More recently, these large-scale studies have been conceived, developed, and delivered by neurosurgical trainees, working under the umbrella of the British Neurosurgical Trainee Research Collaborative (BNTRC). In this paper, we outline the current landscape of large-scale neurosurgical studies in the UK, focusing on the role of trainees in facilitating this research. Importantly, we focus on our experience of trainee-led studies, including the development of the network, current challenges, and future directions. We believe that a similar model can be applied in different settings and countries, which will drive up the quality of neurosurgical research, ultimately benefiting future neurosurgical patients.

Clinical and microbiological spectrum of external ventricular drain related infections (EVDRIs) from a tertiary care center

Background and Objectives

Insertion of an External Ventricular Drain (EVD) is a common and important lifesaving procedure that can lead to morbidity and mortality. This study was conducted to assess the infection rate, risk factors, causative organisms, and outcome of EVDs.

Materials and Methods

A prospective study was undertaken in a tertiary care centre from August 1st to October 30th, 2020. Over 192 patients had undergone insertion of EVDs in the neurosurgical intensive care unit. CSF samples were collected in sterile containers and transported to the laboratory.

Results

A total of 214 EVDs were inserted in 192 patients for 691 days. The median duration for EVD in situ and the mean time between catheter insertion and onset of infection were 14.5 days and 8 days. EVD related infection rate was 19.4 for 1000 EVD days. The most common risk factor for EVD insertion were tumors (55%) followed by hydrocephalus (40%).We identified 25 patients out of 192 (12%) who had clinical signs and symptoms with deranged CSF counts. A total of 13/25 (52%) specimens were culture positives out of which 10 (76.9%) were Gram negative pathogens and 3 (23%) were Gram positive pathogens and 3/10 (30%) Gram negative pathogens were Multidrug resistant organisms (MDROs).

Conclusion

It was observed that longer duration of catheter in situ was an important risk factor for EVD-related infections (ERIs) and also higher frequency of CSF sampling. A proper EVD infection prevention and control protocol must be followed in the form of a checklist at the time of EVD insertion.

Accuracy of heparin-binding protein for the diagnosis of nosocomial meningitis and ventriculitis

Background

The sensitive and accurate diagnosis of nosocomial meningitis and ventriculitis is still a critical problem. This study was designed to explore the diagnostic value of cerebrospinal fluid heparin-binding protein (HBP) in nosocomial meningitis and ventriculitis in comparison with procalcitonin and lactate.

Methods

In this observational study, 323 suspected patients were enrolled, of which 42 participants were excluded because they could not be accurately grouped, 131 subjects who were eventually diagnosed with nosocomial meningitis or ventriculitis and 150 patients in whom infection was ultimately ruled out were included in the final analysis. The main results are expressed as medians (interquartile ranges). The Chi-squared test was used to compare the baseline characteristics. The Mann–Whitney U-test was used for group and subgroup analyses. The area under the receiver operating characteristic curve was calculated to describe the diagnostic accuracy of the biomarkers. Spearman's partial correlation was used to analyze associations between the biomarkers. Statistical significance was set when p value < 0.05.

Results

HBP achieved the largest area under the receiver operating characteristic curve, which was 0.99 (95% confidence interval 0.98—1.00) compared with 0.98 (95% confidence interval 0.96—0.99) for lactate and 0.69 (95% confidence interval 0.62—0.75) for procalcitonin. With a cutoff level at 23 ng/mL, HBP achieved a sensitivity of 97%, a specificity of 95%, a positive predictive value of 93% and a negative predictive value of 98%. The levels of HBP presented no significant discrepancy between patients who received previous empiric anti-infective therapy and those who did not (p > 0.05). Higher concentrations of HBP were present in patients with positive microbiological findings (p < 0.05). Levels of HBP positively correlated with polymorphonuclear cell count (Spearman's rho = 0.68, p < 0.01), white blood cell count (Spearman's rho = 0.57, p < 0.01) and lactate (Spearman's rho = 0.34, p < 0.01).

Conclusions

Cerebrospinal fluid heparin-binding protein is a reliable auxiliary diagnostic marker that is preferable over lactate and procalcitonin in identifying nosocomial meningitis and ventriculitis, and it also contributes to solving the diagnostic difficulties caused by empiric antibiotherapy.

Antibiotic Prophylaxis and Incidence of Infection with External Ventricular Drains and Intra-Cranial Pressure Monitors

Objectives: Guidelines do not recommend extended antibiotic prophylaxis for external ventricular drains (EVD) or intra-cranial pressure (ICP) monitors. The study objective was to determine if infection rates are different for patients receiving antibiotic prophylaxis for EVD or ICP monitors. Patients and Methods: This single-center retrospective cohort reviewed intensive care unit patients who had an EVD or ICP monitor placed. Patients receiving antibiotic prophylaxis were compared with those who did not receive prophylaxis. The primary end point was incidence of central nervous system (CNS) infection. Results: Overall, 228 patients were included, 120 of whom received prophylaxis and 108 who did not receive prophylaxis. The primary end point of CNS infection was not different between groups (18 [17%] vs. 23 [19%]; p = 0.6236). Conclusions: Antibiotic prophylaxis was not associated with a decreased incidence of CNS infection in patients with EVD or ICP monitors. Evaluation of antibiotic use in this patient population is warranted to prevent resistance and adverse drug effects.

Predictors of ventriculostomy-associated infections: A retrospective study of 243 patients

OBJECTIVE

Risk factors of ventriculostomy-associated infection (VAI) reported in the literature are variable due to heterogeneity of external ventricular drainage (EVD) procedures and management. This study aimed to assess the rate of VAI and its risk factors.

METHODS

The authors retrospectively reviewed the medical records of patients older than 18 years who received EVD catheterizations between January 2015 and December 2020.

RESULTS

Among 243 patients with 355 catheters, twenty-three VAIs were identified, yielding VIA rates of 9.5% per patient and 6.5% per catheter. VAI was associated with a longer total EVD duration (29.2 days vs. 15.8 days, P < 0.001), a longer procedural time (72 minutes vs. 40 minutes, P < 0.001), intraoperative ventriculostomy (39.1% vs. 9.1%, P < 0.001), craniotomy (87.0% vs. 60.9%, P = 0.014), and other systemic infections (30.4% vs. 8.2%, P = 0.004). On multivariate analysis, a longer total EVD duration (OR = 1.086, P < 0.001), intraoperative ventriculostomy (OR = 6.119, P = 0.001), and other systemic infections (OR = 4.620, P = 0.015) were associated with VAI. There was no statistical difference between the VAI rates of patients with and without prophylactic EVD exchanges at mean 12.6 days (7.1% vs. 2.2%, P = 0.401).

CONCLUSIONS

Intraoperative ventriculostomy was independently associated with VAI. Prophylactic EVD exchange at 12.6 days did not lower VAI rate.

In vitro study of factors influencing the duration of antimicrobial protection of antimicrobial-impregnated external ventricular drains

BACKGROUND

In vitro and clinical studies assessing the duration of the protective activity of antimicrobial-impregnated external ventricular drains (AI-EVDs) gave conflicting results.

OBJECTIVES

To identify factors associated with decreased antimicrobial activity of AI-EVDs that were not taken into account in previous in vitro models.

METHODS

We performed in vitro experiments with Bactiseal™ AI-EVDs, under different conditions. Tested parameters were chosen to mimic conditions in which AI-EVDs are used: perfusion by saline (at different flow rates) or not perfused, dwelling medium (air, saline, saline+protein, lipid) and temperature. Antimicrobial activity was assessed by measurement of inhibitory diameters of a 0.5 cm portion of an AI-EVD (cut every 2 days) placed onto agar plates covered by a standardized Staphylococcus spp. inoculum (three different isolates). MS was used to measure concentrations of rifampicin and clindamycin after 48 h of dwelling.

RESULTS

In univariate analysis, most of the tested factors were associated with reduced antimicrobial activity: liquid media (as compared with ambient air), perfusion whatever the rate flow (as compared with no perfusion) and presence of protein in the media. In multivariate analysis, dwelling in media (lipid or saline) was the most constantly associated with a reduction of inhibition diameters (P < 0.01), as compared with ambient air. After 48 h of dwelling, the clindamycin concentration was higher than 100 and 450 mg/L in saline and saline+BSA, respectively.

CONCLUSIONS

The medium in which an AI-EVD is dwelling plays a significant role in the duration of AI-EVD activity. These results may explain conflicting results between clinical and in vitro studies.

Effect of External Ventricular Drain Tunnel Length on Cerebrospinal Fluid Infection Rates-A Bayesian Network Meta-Analysis

BACKGROUND

External ventricular drain (EVD)-associated cerebrospinal fluid infection (EACI) remains a major complication associated with EVD. Length of EVD tunnel, an overlooked but modifiable factor, can be associated with increased risk of EACI. The aim of this study is to find the tunnel length associated with least chances of EACI by performing a network meta-analysis.

METHODS

A comprehensive search of different databases was performed to retrieve studies that studied the rates of EACI with different EVD tunnel lengths and a Bayesian network meta-analysis was performed.

RESULTS

Six studies met the inclusion criteria and were included in the network meta-analysis. With 0 cm tunnel length as reference, the odds ratio (OR) for developing EACI was minimum for tunnel length 5-10 cm (OR, 0.027). It was followed by tunnel length of 5 cm (OR, 0.060) and 10 cm (OR, 0.075). The surface under the cumulative ranking curve plot showed that the probability of the tunnel length 5-10 cm (ranked first), 5 cm (ranked second), and 10 cm (ranked third) for being the best EVD tunnel length was found to be 86%, 64%, and 61%, respectively.

CONCLUSIONS

The length for which an EVD is tunneled may have an impact on the rate of EACI. Our network meta-analyses showed that the tunnel length of 5-10 cm was associated with the lowest rates of EACI, with 86% probability of being the best EVD tunnel length. The probability of a patient with 5-10 cm EVD length developing EACI was 2.7% compared with zero tunnel length.

Ventriculitis: Infection or Inflammation

Ventriculitis, or infection of the cerebrospinal fluid, in the presence of external ventricular drains (EVD), is an important complication and associated with substantial mortality, morbidity, and healthcare costs. Further, the conditions that require the insertion of an EVD, such as neurotrauma and subarachnoid hemorrhage, are themselves associated with inflammation of the cerebrospinal fluid. Phenotypically, patients with inflammation of the cerebrospinal fluid can present with very similar symptoms, signs, and laboratory findings to those with infection. This review examines various controversies relating to the definitions, diagnosis, challenges of differentiating infection from inflammation, prevention, and treatment of ventriculitis in patients with EVDs.

Utility of image-guided external ventriculostomy: analysis of contemporary practice in the United Kingdom and Ireland

OBJECTIVE

Freehand external ventricular drain (EVD) insertion is associated with a high rate of catheter misplacement. Image-guided EVD placement with neuronavigation or ultrasound has been proposed as a safer, more accurate alternative with potential to facilitate proper placement and reduce catheter malfunction risk. This study aimed to determine the impact of image-guided EVD placement on catheter tip position and drain functionality.

METHODS

This study is a secondary analysis of a data set from a prospective, multicenter study. Data were collated for EVD placements undertaken in the United Kingdom and Ireland from November 2014 to April 2015. In total, 21 large tertiary care academic medical centers were included.

RESULTS

Over the study period, 632 EVDs were inserted and 65.9% had tips lying free-floating in the CSF. Only 19.6% of insertions took place under image guidance. The use of image guidance did not significantly improve the position of the catheter tip on postoperative imaging, even when stratified by ventricular size. There was also no association between navigation use and drain blockage.

CONCLUSIONS

Image-guided EVD placement was not associated with an increased likelihood of achieving optimal catheter position or with a lower rate of catheter blockage. Educational efforts should aim to enhance surgeons' ability to apply the technique correctly in cases of disturbed cerebral anatomy or small ventricles to reduce procedural risks and facilitate effective catheter positioning.

Silver-impregnated, antibiotic-impregnated or non-impregnated ventriculoperitoneal shunts to prevent shunt infection: the BASICS three-arm RCT

BACKGROUND

Insertion of a ventriculoperitoneal shunt to treat hydrocephalus is one of the most common neurosurgical procedures worldwide. Shunt infection affects up to 15% of patients, resulting in long hospital stays, multiple surgeries and reduced cognition and quality of life.

OBJECTIVES

The aim of this trial was to determine whether or not antibiotic-impregnated ventriculoperitoneal shunts (hereafter referred to as antibiotic shunts) (e.g. impregnated with rifampicin and clindamycin) or silver-impregnated ventriculoperitoneal shunts (hereafter referred to as silver shunts) reduce infection compared with standard ventriculoperitoneal shunts (hereafter referred to as standard shunts).

DESIGN

This was a three-arm, superiority, multicentre, parallel-group randomised controlled trial. Patients and a central primary outcome review panel, but not surgeons or operating staff, were blinded to the type of ventriculoperitoneal shunt inserted.

SETTING

The trial was set in 21 neurosurgical wards across the UK and the Republic of Ireland.

PARTICIPANTS

Participants were patients with hydrocephalus of any aetiology who were undergoing insertion of their first ventriculoperitoneal shunt.

INTERVENTIONS

Participants were allocated 1 : 1 : 1 by pressure-sealed envelope to receive a standard non-impregnated, silver-impregnated or antibiotic-impregnated ventriculoperitoneal shunt at the time of insertion. Ventriculoperitoneal shunts are medical devices, and were used in accordance with the manufacturer's instructions for their intended purpose.

MAIN OUTCOME MEASURES

The primary outcome was time to ventriculoperitoneal shunt failure due to infection. Secondary outcomes were time to failure for any cause, reason for failure (infection, mechanical), types of ventriculoperitoneal shunt infection, rate of infection after first clean (non-infected) revision and health economics. Outcomes were analysed by intention to treat.

RESULTS

Between 26 June 2013 and 9 October 2017, 1605 patients from neonate to 91 years of age were randomised to the trial: n = 36 to the standard shunt, n = 538 to the antibiotic shunt and n = 531 to the silver shunt. Patients who did not receive a ventriculoperitoneal shunt (n = 4) or who had an infection at the time of insertion (n = 7) were not assessed for the primary outcome. Infection occurred in 6.0% (n = 32/533) of those who received the standard shunt, in 2.2% (n = 12/535) of those who received the antibiotic shunt and in 5.9% (n = 31/526) of those who received the silver shunt. Compared with the standard shunt, antibiotic shunts were associated with a lower rate of infection (cause-specific hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80) and a decreased probability of infection (subdistribution hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80). Silver shunts were not associated with a lower rate of infection than standard shunts (cause-specific hazard ratio 0.99, 97.5% confidence interval 0.56 to 1.74). The ventriculoperitoneal shunt failure rate attributable to any cause was 25.0% overall and did not differ between arms. Antibiotic shunts save £135,753 per infection avoided. There were no serious adverse events.

LIMITATIONS

It was not possible to blind treating neurosurgeons to the ventriculoperitoneal shunt type. The return rate for patient-reported outcomes was low. Limitations to the economic evaluation included failure to obtain Hospital Episode Statistics data from NHS Digital, as per protocol. Reliance on patient-level information and costing systems data mitigated these limitations.

CONCLUSIONS

Antibiotic shunts have a reduced infection rate compared with standard shunts, whereas silver shunts do not. Antibiotic shunts are cost-saving.

FUTURE WORK

A sample collection has been established that will enable the study of surrogate markers of ventriculoperitoneal shunt infection in cerebrospinal fluid or blood using molecular techniques. A post hoc analysis to study factors related to shunt failure will be performed as part of a future study. An impact analysis to assess change in practice is planned.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN49474281.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 17. See the NIHR Journals Library website for further project information.

Factors predicting complications following cranioplasty

This study aimed to identify factors that predict complications following cranioplasty, by conducting a retrospective cohort study at a large tertiary care center. Electronic databases were searched to identify all patients who underwent cranioplasty at our institution. Baseline demographics, perioperative variables, and outcomes were extracted. Logistic regression analyses were conducted to identify factors associated with cranioplasty complications. Of the 92 included patients, 15 (16.3%) experienced one or more complications, with 11 (73.3%) experiencing complication within 30 days of cranioplasty. Patients aged ≤60 had decreased odds of all-cause complication (OR 0.058; 95% CI 0.008-0.434) and cranioplasty graft removal (OR 0.035; 95% CI 0.004-0.321) on multivariate analysis. Titanium mesh cranioplasties were associated with increased odds of all-cause complication (OR 19.776; 95% CI 1.021-382.901), and cranioplasty removal (OR 29.780; 95% CI 1.330-666.878). A longer craniectomy-cranioplasty interval was associated with increased odds of cranioplasty removal (OR 1.005; 95% CI 1.000-1.010). An initial craniectomy indication of cerebral infarction was associated with decreased odds of all-cause complication (OR 0.042; 95% CI 0.002-0.876) and cranioplasty removal (OR 0.032; 95% CI 0.001-0.766). Elderly patients may require more aggressive follow-up and antibiotic prophylaxis in the postoperative period following cranioplasty. Additionally, avoiding the use of titanium mesh cranioplasties and prolonged craniectomy-cranioplasty intervals may further reduce complications.

Chlorhexidine dressings could reduce external ventricular drain infections: results from a systematic review and meta-analysis

BACKGROUND

The incidence of external ventricular drain (EVD) infections remains high. Chlorhexidine dressings have demonstrated efficacy in reducing infections associated with indwelling catheters at other body sites, although evidence for their use with EVDs is limited.

AIM

The aim of this systematic review and meta-analysis was to evaluate the efficacy of chlorhexidine dressings in reducing EVD associated cerebrospinal fluid infection (EVDAI).

METHODS

Systematic review and meta-analysis. MEDLINE, EMBASE and the Cochrane library were queried for articles from inception. The primary outcome was the incidence of EVDAI. Secondary outcomes included device safety, microbiological outcomes and shunt-dependency.

FINDINGS

From 896 unique records, 5 studies were included of which 4 presented suitable data for quantitative analysis including 3 case series and one underpowered randomised controlled trial. There was a high risk of bias in all studies. 880 patients were included with a mean age of 57.7 years (95% CI 57.4-58.0 years). In primary outcome analysis, the chlorhexidine dressing group had a significantly lower incidence of EVDAI (1.7% vs. 7.9%, RD = 0.07, 95% CI 0.00 - 0.13, p = 0.04).

CONCLUSION

Chlorhexidine dressings may reduce the incidence of EVDAI but require future study in randomised trials to definitively determine efficacy.

Implementation of an Automated Cerebrospinal Fluid Drainage System for Early Mobilization in Neurosurgical Patients

BACKGROUND

Automated cerebrospinal fluid (CSF) drainage systems allow for the mobilization of patients with an external CSF drain. The aim of this study is to describe the implementation of an automated CSF drainage system in neurosurgical patients with external CSF drains.

METHODS

A feasibility study was performed using an automated CSF drainage system (LiquoGuard^®7, Möller Medical GmbH, Fulda, Germany) in adult neurosurgical patients treated with external lumbar or external ventricular drains between December 2017 and June 2020. Limited mobilization was allowed-patients were allowed to adjust their inclined beds, sit in chairs and walk under the supervision of a nurse or physical therapist. The primary outcome was the number of prematurely terminated drainage sessions.

RESULTS

Twenty-three patients were included. Drainage was terminated prematurely in eight (35%) patients. In three (13%) of these patients, drainage was terminated due to signs of hydrocephalus. Pressure-controlled drainage in patients with external lumbar drains (ELD) showed inaccurate pressure curves, which was solved by using volume-controlled drainage in ELD patients.

CONCLUSION

The implementation of an automated CSF drainage system (LiquoGuard^®7) for CSF drainage allows for early mobilization in a subset of patients with external CSF drains. External lumbar drains require volume-based drainage rather than differential pressure-dependent drainage.

The effect of external ventricular drain tunneling length on CSF infection rate in pediatric patients: a randomized, double-blind, 3-arm controlled trial

OBJECTIVE

The role of tunneling an external ventricular drain (EVD) more than the standard 5 cm for controlling device-related infections remains controversial.

METHODS

This is a randomized, double-blind, 3-arm controlled trial done in the Children's Medical Center in Tehran, Iran. Pediatric patients (< 18 years old) with temporary hydrocephalus requiring an EVD and no evidence of CSF infection or prior EVD insertion were enrolled. Patients were randomly assigned (1:1:1) into the following arms: 5-cm (standard; group A); 10-cm (group B); or 15-cm (group C) EVD tunnel lengths. The investigators, parents, and person performing the analysis were masked. The surgeon was informed of the length of the EVD by the monitoring board just before operation. Patients were followed until the EVD's fate was established. Infection rate and other complications related to EVDs were assessed.

RESULTS

A total of 105 patients were enrolled in three random groups (group A = 36, group B = 35, and group C = 34). The EVD was removed because there was no further need in most cases (67.6%), followed by conversion to a new EVD or ventriculoperitoneal shunt (15.2%), infection (11.4%), and spontaneous discharge without further CSF diversion requirement (5.7%). No statistical difference was found in infection rate (p = 0.47) or EVD duration (p = 0.81) between the three groups. No group reached the efficacy point sooner than the standard group (group B: hazard ratio 1.21, 95% CI 0.75-1.94, p = 0.429; group C: hazard ratio 1.03, 95% CI 0.64-1.65, p = 0.91).

CONCLUSIONS

EVD tunnel lengths of 5 cm and longer did not show a difference in the infection rate in pediatric patients. Indeed, tunneling lengths of 5 cm and greater seem to be equally effective in preventing EVD infection. Clinical trial registration no.: IRCT20160430027680N2 (IRCT.ir).

A simple and cost-effective model for ventricular catheter placement training: technical note

OBJECTIVE

External ventricular drain (EVD) placement is one of first cranial procedures neurosurgery residents are expected to perform independently. While proper training improves patient outcomes, there are few options for practicing EVD placement prior to placing the EVD in patients in a clinical setting. Proposed solutions to this include using cadaveric models and virtual simulations, but barriers exist with these as well in regard to authenticity. EVD simulators using virtual reality technologies are a promising new technique for training, but the cost of these devices poses a barrier to general/widespread accessibility among smaller programs or underserved hospitals. The authors desribe a novel, yet simple, and cost-effective technique (less than $5 per mold) for developing a brain model constructed of homemade ballistics gelatin that can be used for teaching and practicing the placement of EVD.

METHODS

A brain model is made with ballistics gelatin using an anatomically correct skull model as a mold. A 3D-printed ventricular system model is used to create a mold of an anatomically correct ventricular system in the brain model. A group of medical students (n = 10) were given a basic presentation about EVD placement, including standard landmarks and placement techniques, and were also shown a demonstration of EVD placement on the brain model. They were then allowed to perform an EVD placement using the brain model. The students were surveyed on their experience with using the brain model, including usability and practicality of the model. Accuracy of EVD placement by each student was also assessed, with adequate position of catheter tip being in the ipsilateral frontal horn.

RESULTS

The final product is fairly inexpensive and easy to make. It is soft enough to pass a catheter through, but it is also firm enough to maintain its shape, including a cavity representing the lateral ventricles. The dense gelatin holds the catheter in its final resting position, while the two halves are separated and inspected. All participants in the test group of medical students reported that the brain model was easy to use, helped them understand the steps and technique of EVD placement, and provided good feedback on the ideal position of ventricular catheters. All of the participants in the group had adequate positioning of their ventricular catheters after one attempt.

CONCLUSIONS

The presented brain model is easy to replicate, inexpensive, anatomically accurate, and provides a medium for neurosurgeons to teach and practice ventricular catheter placement in a risk-free environment.

Severe infections in neurocritical care

PURPOSE OF REVIEW

We have highlighted the recent advances in infection in neurocritical care.

RECENT FINDINGS

Central nervous system (CNS) infections, including meningitis, encephalitis and pyogenic brain infections represent a significant cause of ICU admissions. We underwent an extensive review of the literature over the last several years in order to summarize the most important points in the diagnosis and treatment of severe infections in neurocritical care.

SUMMARY

Acute brain injury triggers an inflammatory response that involves a complex interaction between innate and adaptive immunity, and there are several factors that can be implicated, such as age, genetic predisposition, the degree and mechanism of the injury, systemic and secondary injury and therapeutic interventions. Neuroinflammation is a major contributor to secondary injury. The frequent and challenging presence of fever is a common denominator amongst all neurocritical care patients.

Complications of external cerebrospinal fluid drainage in aneurysmal subarachnoid haemorrhage

Background

The need for external cerebrospinal fluid (CSF) drains in aneurysmal subarachnoid haemorrhage (aSAH) patients is common and might lead to additional complications.

Objective

A relation between the presence of an external CSF drain and complication risk is investigated.

Methods

A prospective complication registry was analysed retrospectively. We included all adult aSAH patients admitted to our academic hospital between January 2016 and January 2018, treated with an external CSF drain. Demographic data, type of external drain used, the severity of the aSAH and complications, up to 30 days after drain placement, were registered. Complications were divided into (1) complications with a direct relation to the external CSF drain and (2) complications that could not be directly related to the use of an external CSF drain referred to as medical complications

Results

One hundred and forty drains were implanted in 100 aSAH patients. In total, 112 complications occurred in 59 patients. Thirty-six complications were drain related and 76 were medical complications. The most common complication was infection (n = 34). Drain dislodgement occurred 16 times, followed by meningitis (n = 11) and occlusion (n = 9). A Poisson model showed that the mean number of complications raised by 2.9% for each additional day of drainage (95% CI: 0.6–5.3% p = 0.01).

Conclusion

Complications are common in patients with aneurysmal subarachnoid haemorrhage of which 32% are drain-related. A correlation is present between drainage period and the number of complications. Therefore, reducing drainage period could be a target for further improvement of care.

Is External Ventricular Drain Infection Predictable in Neurosurgery Patients? A Following-up Study in Iran

Background: External ventricular drains (EVDs) infection is a life-threatening complication. Objectives: To investigate the rate of EVDs infection and its predictive factors in neurosurgery patients hospitalized at a tertiary teaching hospital in Iran. Methods: In this survey, all patients referred to a subspecialty hospital in Tehran (Iran) with an external ventricular drain (EVDs) from Jun 23, 2018, to Jun 23, 2019, are monitored within 30 days of EVDs placement for infection. Data on demographic information, underlying diseases, number of EVD replacements, length of hospital stay, type consumed antibiotic before neurosurgery, length of tunneling, type of airway, duration of mechanical ventilation, duration of surgery(hours), surgeon name, APACHE II score, length of intensive care unit stay are collected. The diagnosis was based on the Center for Diseases Control and Prevention criteria for meningitis/ventriculitis and clinical vision of infectious or critical care specialists. A logistic regression model was developed to identify factors that can predict the infection. Results: Of 81 patients with EVDs, 39 (48.1%) were infected. The mean age of patients was 44.33 ± 19.5 years, and 55.6% of them were male. According to the multiple logistic regression analysis, mechanical ventilation for more than 6 days (OR: 2.5, 95% CI: 1.6 - 3.56, P = 0.04) and length of tunneling > 5 cm (OR: 1.98, 95%CI: 1.87 - 4.76, P = 0.02) were identified as factors that could predict EVD infection. Also, consuming ceftazidime + vancomycin, as a prophylaxis agent, had a lower odds ratio for EVD infection (OR:0.4, 95% CI: 0.08 - 0.84, P = 0.04). Conclusions: Regarding the predictive factors of EVDs infection, either in the present study or other studies, there should be strategies to manage this life-threatening infection in neurosurgery patients.

Use of Clustering to Investigate Changes in Intracranial Pressure Waveform Morphology in Patients with Ventriculitis

OBJECTIVE

This study aimed to examine whether changes in intracranial pressure (ICP) waveform morphologies can be used as a biomarker for early detection of ventriculitis.

METHODS

Consecutive patients (N = 1653) were prospectively enrolled in a hemorrhage outcomes study from 2006 to 2018. Of these, 435 patients (26%) required external ventricular drains (EVDs) and 76 (17.5% of those with EVDs) had ventriculitis treated with antibiotics. Nineteen patients (25% of those with ventriculitis) showed culture-positive cerebrospinal fluid (CSF) and were included in the present analysis. CSF was routinely cultured three times per week and additionally if infection was suspected. EVDs were left open for drainage, with ICP assessed hourly by clamping. Using wavelet analysis, we extracted uninterrupted segments of ICP waveforms. We extracted dominant pulses from continuous high-resolution data, using morphological clustering analysis of intracranial pressure (MOCAIP). Then we applied k-means clustering, using the dynamic time warping distance to obtain morphologically similar groupings. Finally, metaclusters and further-split clusters (when equipoise existed) were categorized for broad comparison by clinician consensus.

RESULTS

We extracted 275,911 dominant pulses from 459.9 h of EVD data. Of these, 112,898 pulses (40.9%) occurred before culture positivity, 41,300 pulses (15.0%) occurred during culture positivity, and 121,713 pulses (44.1%) occurred after it. K-means identified 20 clusters, which were further grouped into metaclusters: tri-/biphasic, single-peak, and artifactual waveforms. Prior to ventriculitis, 61.8% of dominant pulses were tri-/biphasic; this percentage reduced to 22.6% during ventriculitis and 28.4% after it (p < 0.0001). One day before the first positive cultures were collected, the distribution of metaclusters changed to include more single-peak and artifactual ICP waveforms (p < 0.0001).

CONCLUSION

The distribution of ICP waveform morphology changes significantly prior to clinical diagnosis of ventriculitis and may be a potential biomarker.