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 infection associated with the use of external ventricular drainage: a systematic review with meta-analysis

BACKGROUND

Infection associated with the use of the External Ventricular Drainage (EVD) catheter in neurosurgery is linked to high morbidity and mortality, and various mechanisms are related to its occurrence. This systematic review aims to summarise and update the risk factors associated with EVD-related infection.

METHOD

Systematic review with meta-analysis, utilising grey literature and indexed databases.

FINDINGS

Thirty studies were included, of which nine contributed to the meta-analysis. The reported frequency of EVD-related infection varied from 1.9% to 36%, and the diagnostic criteria for infection were not standardized, with the presence of a positive culture being the most common. The primary microorganisms identified were Staphylococcus sp. and Pseudomonas sp. Key risk factors included duration of catheterisation, frequency of maintenance care, reinsertion, or number of drains. The results of the meta-analysis showed a significant effect in patients with prolonged use of EVDs, with an increase in risk of 1.47 (OR) [CI 95%, 1.03; 2,10] for each day of use (p=0.03), and showed that the number of cerebrospinal fluid collections was higher in the group with infection (p=0.00), while a greater number of EVDs used was related to a significant effect on infection rates (p=0.00), which were revealed from studies with low heterogeneity (I2: 0%).

CONCLUSION

The results indicated studies with high heterogeneity and low quality of evidence, with risk factors associated with the maintenance or management of EVD.

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.

Risk Factors for External Ventricular Drainage-Related Infection: A Systematic Review and Meta-analysis

Background and Objectives

External ventricular drainage (EVD) is one of the most commonly performed neurosurgical procedures, but EVD-related infection constitutes a significant health concern. Yet, little consensus identifies the risk factors for the development of EVD-related infection. Therefore, we performed a meta-analysis to systematically summarize existing evidence on the incidence and risk factors for EVD-related infection.

Methods

PubMed, Embase, and the Cochrane Library databases from database inception to February 28, 2022, were searched for all studies investigating the incidence and risk factors for EVD-related infection. Data were assessed by R-4.2.0 software. The meta-analysis was used to calculate pooled odds ratios (OR) and 95% confidence intervals (CI).

Results

A total of 48 studies were included. Among the 29 factors analyzed, statistically significant risk factors were subarachnoid hemorrhage(SAH)/intraventricular hemorrhage(IVH) (OR = 1.48, 95% CI = 1.20-1.82, p < 0.001), concomitant systemic infection (OR = 1.90, 95% CI = 1.34-2.70, p < 0.001), other neurosurgical procedures (OR = 1.76, 95% CI = 1.02-3.04, p = 0.041), change of catheter (OR = 5.05, 95% CI = 3.67-6.96, p < 0.001), bilateral EVDs (OR = 2.25, 95% CI = 1.03-4.89, p = 0.041), (cerebrospinal fluid) CSF leak (OR = 3.19, 95% CI = 2.12-4.81, p < 0.001) and duration of EVD >7 days (OR = 4.62, 95% CI = 2.26-9.43, p < 0.001). The use of silver-coated catheters (OR = 0.57, 95% CI = 0.38-0.87, p = 0.008) and antibiotic-impregnated catheters (OR = 0.60, 95% CI = 0.41-0.88, p = 0.009) might help reduce the risk of infection. No significant difference was indicated in studies evaluating factors like diabetes mellitus (OR = 1.25, 95% CI = 0.90-1.75, p = 0.178), steroids used (OR = 1.52, 95% CI = 0.96-2.4, p = 0.074), prophylactic antibiotics(OR = 0.87, 95% CI = 0.66-1.14, p = 0.308).

Discussion

The meta-analysis of various relevant factors in the onset of EVD-related infection in patients submitted to EVD enabled us to establish a more probable profile of the patients who are more likely to develop it during the treatment.

The insertion and management of an external ventricular drain in pediatric patients with hydrocephalus associated with medulloblastoma

An external ventricular drain (EVD) is used to facilitate cerebrospinal fluid (CSF) removal in medulloblastoma patients suffering from hydrocephalus. It is essential to recognize that EVD management plays a crucial role in influencing the incidence of drain-related complications. However, the ideal method for EVD management remains undetermined. Our research sought to examine the safety of EVD placement and the impact of EVD on the incidences of intracranial infections, postresection hydrocephalus, and posterior fossa syndrome (PFS). We conducted a single-center observational study involving a cohort of 120 pediatric medulloblastoma patients who were treated from 2017 to 2020. The rates of intracranial infection, postresection hydrocephalus, and PFS were 9.2%, 18.3%, and 16.7%, respectively. EVD did not influence the occurrence of intracranial infection (p = 0.466), postresection hydrocephalus (p = 0.298), or PFS (p = 0.212). A gradual EVD weaning protocol correlated with an elevated incidence of postresection hydrocephalus (p = 0.033), whereas a rapid weaning approach resulted in 4.09 ± 0.44 fewer drainage days (p < 0.001) than the gradual weaning strategy. EVD placement (p = 0.010) and intracranial infection (p = 0.002) were linked to delayed speech return, whereas a longer duration of drainage was conducive to the recovery of language function (p = 0.010). EVD insertion was not correlated with the incidence of intracranial infection, postoperative hydrocephalus, or PFS. The optimal EVD management method should encompass a rapid EVD weaning strategy, followed by prompt drain closure. We have presented additional evidence to improve the safety of EVD insertion and management in neurosurgical patients to ultimately facilitate the establishment of standardized institutional/national implementation and management protocols.

Feasibility of Prompt Lumbar Drainage in Patients with Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Numerous studies have shown that continuous lumbar drainage (LD) reduces spontaneous subarachnoid hemorrhage (SAH)-related complications, decreasing the incidence of cerebral vasospasm, delayed cerebral ischemia , and hydrocephalus in patients treated with coiling or clipping, but performing LD before securing the aneurysm is still controversial. Our hospital has been implementing prompt LD for several years, and we present the results in this paper.

METHODS

Between January 2014 and December 2020, a total of 438 patients with SAH were included in this retrospective study. The indication for prompt LD was aneurysmal SAH of modified Fisher grade III or higher without dense intraventricular hemorrhage with obstructive hydrocephalus requiring extraventricular drainage or large intracranial hemorrhage requiring immediate decompression. Prompt LD was performed for 229 patients with SAH, and the control group included 209 patients. We compared in-hospital mortality and vasospasm or hydrocephalus occurrence and procedure-related complications between the two groups.

RESULTS

The in-hospital mortality rate was 7.4% for patients with prompt LD and 14.4% for patients without LD, and the difference was significant (P = 0.019). Vasospasm occurred in 10% of patients with prompt LD and 16.7% of controls (P = 0.039). Hydrocephalus requiring extraventricular drainage occurred in 10.9% of the LD group and 28.7% of the control group (P < 0.001). Rebleeding occurrence was 3.1% in the prompt LD group and 5.7% in the non-LD group (P = 0.168). Cerebrospinal fluid infection occurred in 0.4% of the prompt LD group and 1.4% of controls(P = 0.272).

CONCLUSIONS

Prompt LD is a feasible option for treating patients with selective aneurysmal SAH.

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.

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.

Risk factors and outcomes associated with external ventricular drain infections

BACKGROUND

Insertion of an external ventricular drain (EVD) is a common neurosurgical procedure which may lead to serious complications including infection. Some risk factors associated with EVD infection are well established. Others remain less certain, including specific indications for placement, prior neurosurgery, and prior EVD placement.

OBJECTIVE

To identify risk factors for EVD infections.

METHODS

We reviewed all EVD insertions at our institution from March 2015 through May 2019 following implementation of a standardized infection control protocol for EVD insertion and maintenance. Cox regression was used to identify risk factors for EVD infections.

RESULTS

479 EVDs placed in 409 patients met inclusion criteria, and 9 culture-positive infections were observed during the study period. The risk of infection within 30 days of EVD placement was 2.2% (2.3 infections/1,000 EVD days). Coagulase-negative staphylococci were identified in 6 of the 9 EVD infections). EVD infection led to prolonged length of stay post-EVD-placement (23 days vs 16 days; P = .045). Cox regression demonstrated increased infection risk in patients with prior brain surgery associated with cerebrospinal fluid (CSF) diversion (HR, 8.08; 95% CI, 1.7-39.4; P = .010), CSF leak around the catheter (HR, 21.0; 95% CI, 7.0-145.1; P = .0007), and insertion site dehiscence (HR, 7.53; 95% CI, 1.04-37.1; P = .0407). Duration of EVD use >7 days was not associated with infection risk (HR, 0.62; 95% CI, 0.07-5.45; P = .669).

CONCLUSION

Risk factors associated with EVD infection include prior brain surgery, CSF leak, and insertion site dehiscence. We found no significant association between infection risk and duration of EVD placement.

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.

Risk Factors Promoting External Ventricular Drain Infections in Adult Neurosurgical Patients at the Intensive Care Unit-A Retrospective Study

Objectives: Multiple risk factors have been described to be related to external ventricular drain (EVD) associated infections, with results varying between studies. Former studies were limited by a non-uniform definition of EVD associated infection, thus complicating a comparison between studies. In this regard, we assessed risk factors promoting EVD associated infections and propose a modified practice-oriented definition of EVD associated infections.

Methods: We performed a retrospective, single-center study on patients who were treated with an EVD, at the neurosurgical intensive care unit (ICU) at a tertiary center between 2008 and 2019. Based on microbiological findings and laboratory results, patients were assigned into an infection and a non-infection group. Patient characteristics and potential risk factors were compared between the two groups (p < 0.05). Receiver operating characteristics (ROC) for significant clinical, serum laboratory and cerebrospinal fluid (CSF) parameters were calculated.

Results: In total, 396 patients treated with an EVD were included into the study with a mean age of 54.3 (range: 18–89) years. EVD associated infections were observed in 32 (8.1%) patients. EVD insertion at another hospital (OR 3.86), and an increased CSF sampling frequency of more than every third day (OR 12.91) were detected as major risk factors for an EVD associated infection. The indication for EVD insertion, surgeon's experience, the setting of EVD insertion (ICU vs. operating room) and the operating time did not show any significant differences between the two groups. Furthermore, ROC analysis showed that clinical, serum laboratory and CSF parameters did not provide specific prediction of EVD associated infections (specificity 44.4%). This explains the high overtreatment rate in our cohort with the majority of our patients who received intrathecal vancomycin (63.3%), having either negative microbiological results (n = 12) or were defined as contaminations (n = 7).

Conclusions: Since clinical parameters and blood analyzes are not very predictive to detect EVD associated infections in neurosurgical patients, sequential but not too frequent microbiological and laboratory analysis of CSF are still necessary. Furthermore, we propose a uniform classification for EVD associated infections to allow comparability between studies and to sensitize the treating physician in determining the right treatment.

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.

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.

Efficacy of antimicrobial medicated ventricular catheters: a network meta-analysis with trial sequential analysis

There is paucity of evidence regarding relative performance of antibiotic-medicated (AM), silver-medicated (SM) and non-medicated (NM) ventricular catheters in controlling infection rate. We aim to quantitatively synthesize the current evidence after addition of the three-armed British Antibiotic and Silver Impregnated Catheters for ventriculoperitoneal Shunts (BASICS) trial, understand the need for further evidence using trial sequential analysis (TSA) and incorporate the indirect evidence using network meta-analysis (NMA). Randomized controlled trials (RCTs) comparing AM, SM and NM ventriculoperitoneal shunt (VPS) or external ventricular drain (EVD) were included. Antibiotic-medicated VPS show a significantly lower infection rate as compared to non-medicated VPS (RR 0.44; 95% CI: 0.27-0.73; p = 0.001), however, TSA reveals need for further evidence. SM including both EVD as well as VPS were found to be inferior to AM while no significant difference was found in comparison to the NM catheters. In NMA for VPS, the AM were found to be significantly better than SM (RR 0.41, 95% CI: 0.22-0.75) as well as NM (RR 0.42; 95% CI: 0.25-0.71) with a SUCRA of 99.8% and a mean rank of 1. However, antibiotic medicated shunts did not show a statistically significant association with reoperation rate (RR 0.99; 95% CI:0.81-1.20; p = 0.9) with no further need for evidence as per TSA.

Healthcare-associated ventriculitis: current and emerging diagnostic and treatment strategies

Introduction: Healthcare-associated ventriculitis and meningitis occur after neurosurgical procedures, is associated with an adverse outcome in the majority of patients and represent a diagnostic challenge to clinicians. As the cerebrospinal fluid (CSF) culture is the cornerstone of diagnosis, obtaining CSF studies prior to starting antibiotic therapy is key.Areas covered: This review will evaluate the incidence, risk factors, clinical presentation, diagnosis, empirical intravenous antibiotic therapy, adjunctive intrathecal therapy, microbiology, prognosis, and prevention of HCAVM. We highlight the challenges and limitations of the currently available diagnostic methods and definitions and explore novel technologies. Our review included the search for published literature until June 2020.Expert opinion: Despite available preventive measures, HCAVM continues to occur and to be independently associated with significant neurological morbidity and mortality in the majority of patients. The cornerstone of the diagnosis of HCAVM is a positive CSF culture but the microbiological yield is reduced to ~50% with prior antimicrobial therapy. Although the CSF profile is not affected by antibiotic therapy it has a fair diagnostic accuracy. Future research efforts should concentrate in identifying novel diagnostic tools such as polymerase chain reaction (PCR) or metagenomic sequencing.

Securing CSF catheters to the skin: from sutures and bolt system to subcutaneous anchoring device towards zero complications

INTRODUCTION

Securing the catheter to the skin either with sutures or staples and to the skull with bolt system still represents the most common options in the management of CSF external drainage. However, these options bear an unavoidable risk of complications. This problem is common to vascular accesses and has been successfully overcome with the introduction of device for subcutaneous anchoring (SecurAcath®, Interrad Medical, Inc., Plymouth, Minnesota), which has rapidly become the standard of care in this field.

METHODS

We report our experience with the use of SecurAcath® to secure CSF drainage, either ventricular or spinal. Results were compared with literature data.

RESULTS

Since 2015, SecurAcath® was used in 209 patients (mean age 7 years) to secure 195 external cranial catheters (either ventricular or subdural or intralesional) and 16 spinal drainages. Indwell time ranged from 5 to 30 days. No complication related to the use of the device was observed. In particular, there was no case of dislocation or accidental pullout of the catheter. Rate of infection, or superinfection in case of ventricular catheter implanted for CSF infection, was null.

CONCLUSIONS

SecurAcath® is a safe and effective device to secure CSF external catheters, with several relevant advantages, including easy placement and maintenance. Moreover, it may stay in place for the whole duration of the catheter without any skin tissue trauma and allows a complete antisepsis of the exit site, thus reducing local skin complications. This factor has significant impact on the reduction of infection rate of external CSF catheters.

Systemic Antimicrobial Prophylaxis and Antimicrobial-Coated External Ventricular Drain Catheters for Preventing Ventriculostomy-Related Infections: A Meta-Analysis of 5242 Cases

BACKGROUND

External ventricular drain (EVD) placement is essential for the management of many neurocritical care patients. However, ventriculostomy-related infection (VRI) is a serious complication, and there remains no well-established protocol guiding use of perioperative or extended antibiotic prophylaxis to minimize risk of VRI.

OBJECTIVE

To analyze published evidence on the efficacy of extended prophylactic antimicrobial therapy and antibiotic-coated external ventricular drains (ac-EVDs) in reducing VRI incidence.

METHODS

We searched PubMed for studies related to VRIs and antimicrobial prophylaxis. Eligible articles reported VRI incidence in control and treatment cohorts evaluating prophylaxis with either extended systemic antibiotics (> 24 hr) or ac-EVD. Risk ratios and VRI incidence were aggregated by prophylactic strategy, and pooled estimates were determined via random or mixed effects models. Study heterogeneity was quantified using I2 and Cochran's Q statistics. Rigorous assessment of study bias was performed, and PRISMA guidelines were followed throughout.

RESULTS

Across 604 articles, 19 studies (3%) met eligibility criteria, reporting 5242 ventriculostomy outcomes. Extended IV and ac-EVD prophylaxis were associated with risk ratios of 0.36 [0.14, 0.93] and 0.39 [0.21, 0.73], respectively. Mixed effects analysis yielded expected VRI incidence of 13% to 38% with no prophylaxis, 7% to 18% with perioperative IV prophylaxis, 3% to 9% with either extended IV or ac-EVD prophylaxis as monotherapies, and as low as 0.8% to 2% with extended IV and ac-EVD dual prophylaxis.

CONCLUSION

Management with both extended systemic antibiotics and ac-EVDs could lower VRI risk in ventriculostomy patients, but the impact on associated morbidity and mortality, healthcare costs, and length of stay remain unclear.

Validation of Noninvasive Absolute Intracranial Pressure Measurements in Traumatic Brain Injury and Intracranial Hemorrhage

BACKGROUND

Increased intracranial pressure (ICP) causes secondary damage in traumatic brain injury (TBI), and intracranial hemorrhage (ICH). Current methods of ICP monitoring require surgery and carry risks of complications.

OBJECTIVE

To validate a new instrument for noninvasive ICP measurement by comparing values obtained from noninvasive measurements to those from commercial implantable devices through this pilot study.

METHODS

The ophthalmic artery (OA) served as a natural ICP sensor. ICP measurements obtained using noninvasive, self-calibrating device utilizing Doppler ultrasound to evaluate OA flow were compared to standard implantable ICP measurement probes.

RESULTS

A total of 78 simultaneous, paired, invasive, and noninvasive ICP measurements were obtained in 11 ICU patients over a 17-mo period with the diagnosis of TBI, SAH, or ICH. A total of 24 paired data points were initially excluded because of questions about data independence. Analysis of variance was performed first on the 54 remaining data points and then on the entire set of 78 data points. There was no difference between the 2 groups nor was there any correlation between type of sensor and the patient (F[10, 43] = 1.516, P = .167), or the accuracy and precision of noninvasive ICP measurements (F[1, 43] = 0.511, P = .479). Accuracy was [-1.130; 0.539] mm Hg (CL = 95%). Patient-specific calibration was not needed. Standard deviation (precision) was [1.632; 2.396] mm Hg (CL = 95%). No adverse events were encountered.

CONCLUSION

This pilot study revealed no significant differences between invasive and noninvasive ICP measurements (P < .05), suggesting that noninvasive ICP measurements obtained by this method are comparable and reliable.

Impact of an educational program on reducing health care-associated meningitis or ventriculitis in the neurosurgical intensive care unit

BACKGROUND

Health care-associated meningitis or ventriculitis (HCAMV) is a serious complication in different neurosurgical procedures and is associated with significant morbidity and mortality. We aimed to investigate whether an educational intervention program could reduce the HCAMV incidence in patients undergoing postsurgery external ventricular drainage and wound management.

METHODS

We enrolled 2,904 patients from the neurosurgery intensive care unit between January 1, 2016 and December 31, 2018. The medical staff undertook an educational program developed by a multidisciplinary team on correct external ventricular drainage insertion and maintenance. The program included a 9-page self-learning module on the HCAMV risk factors and operational improvements. Each participant completed a pre- and posttest on their HCAMV knowledge.

RESULTS

We found that 38 of 693 (5.48%) patients presented with infection in the preintervention 9-month period. In the 27-month postintervention period, the proportion of HCAMV incidence dropped by 52.19% (P < .0001) to 58 of 2,211 (2.62%) patients.

CONCLUSIONS

Educational intervention aimed at the neurosurgery intensive care unit staff could significantly reduce the HCAMV rate, leading to a significant decline in the cost, morbidity, and mortality caused by neurosurgical procedures.

Effectiveness of a Chlorhexidine Dressing on Silver-coated External Ventricular Drain-associated Colonization and Infection: A Prospective Single-blinded Randomized Controlled Clinical Trial

Background

Observational studies have shown that dressings containing chlorhexidine gluconate (CHX) lower the incidence external ventricular drain (EVD)-associated infections (EVDAIs). This prospective, randomized controlled trial (RCT) studies the efficacy of CHX-containing dressings in reducing bacterial colonization.

Methods

In this RCT, patients aged ≥18 years undergoing emergency EVD placement were randomly given either a CHX-containing or an otherwise identical control dressing at the skin exit wound. The primary end-point was bacterial regrowth in cultured skin swab samples of the EVD exit wound. The secondary end-points were catheters processed by sonication, clinically diagnosed EVDAI and surgical treatment of hydrocephalus.

Results

From October 2013 to January 2016, a total of 57 patients were randomized to receive either a CHX or a control dressing (29 and 28 patients, respectively). Cutaneous bacterial regrowth at the EVD exit wound was significantly reduced over time (geometric mean ratio, 0.18; 95% confidence interval, .08-.42; P < .001). The incidence of colonized catheters was lower in the CHX group (5 of 28; 18%) than in the control group (10 of 27; 33%), with less microbial colonization on the subcutaneous portion. The infection rate was 4 of 28 (14%) in the CHX group, compared with 7 of 27 (26%) in the control group, with a substantially lower hydrocephalus treatment rate (7 of 28 [25%] vs 14 of 27 [52%], respectively).

Conclusion

Our data support the use of CHX dressings to reduce EVD exit site contamination, potentially reducing EVDAIs and permanent cerebrospinal fluid diversion procedures for hydrocephalus.

Clinical Trials Registration

NCT02078830.

Natural history of ventriculostomy-related infection under appropriate treatment and risk factors of poor outcome: a retrospective study

OBJECTIVE

The authors aimed to describe the natural history of ventriculostomy-related infections (VRIs) under appropriate treatment and to assess risk factors for poor outcome.

METHODS

All patients older than 18 years in whom an external ventricular drain (EVD) had been implanted and who had developed a VRI requiring treatment were included in this retrospective study. D0 was defined as the first day of antibiotic administration. Clinical and biological parameters were compared each day beginning with D1 and ending with D10 to those of D0. The authors defined D0 in a control group as the day a CSF culture came back positive, without any sign of infection. The authors then searched for poor prognostic factors in the VRI group.

RESULTS

Among 567 patients requiring an EVD between January 2007 and October 2017, 39 developed a VRI. Most were monomicrobial infections, and 47 microbes were responsible (45% were gram-positive cocci). Clinical parameters differed significantly from the control group during the first 2 days and then returned to baseline. The CSF parameters differed significantly from the control group for a longer period, returning to baseline after 5 days. CSF sterilization occurred in a median time of 2 days. An intrathecal route or EVD exchange was not associated with a poor outcome. No clinical or biological parameter between D3 and D5 was linked to outcome.

CONCLUSIONS

Clinical status improved faster than CSF parameters (before and after D5, respectively). Some CSF parameters remained abnormal until D10. Body temperature and microbiological cultures normalized faster than other parameters.

Durability of antimicrobial activity of antibiotic-impregnated external ventricular drains: a prospective study

Background

Antibiotic-impregnated external ventricular drains (AI-EVDs) have a debated efficacy in clinical studies.

Objectives

Our aim was to assess the durability of antimicrobial activity of AI-EVDs used in clinical settings.

Methods

From April 2017 to January 2018, all consecutive AI-EVDs (Bactiseal™) inserted in adult patients were prospectively included. After removal, each AI-EVD was cultured and assessed for antimicrobial activity on both internal and external sides of AI-EVDs. Catheters were each challenged with a single Staphylococcus strain [MSSA, MRSA or methicillin-resistant Staphylococcus epidermidis (MRSE)]. MS was used to measure residual concentrations of rifampicin and clindamycin.

Results

Sixty-five AI-EVDs were included (56 patients). Among these, 21 were challenged with MSSA, 23 with MRSA and 21 with MRSE. Five ventriculostomy-related colonizations (9%) and two ventriculostomy-related infections (4%) occurred. Staphylococcus was the main bacterium responsible for colonization (4/5). AI-EVD inhibition decreased significantly against MRSA and MRSE according to duration of catheterization (for external and internal sides, P < 0.02) and overall volume of CSF drained (P < 0.005 for both sides against MRSE, P < 0.005 for external side against MRSA), but not against MSSA. Clindamycin concentration was not correlated with duration of catheterization or CSF volume drained, but <20% of initial concentration was recovered even after 5 days of AI-EVD dwelling. Conversely, rifampicin concentration showed a rapid and significant decline correlated to duration and CSF volume (P < 0.001 and P = 0.03, respectively).

Conclusions

Antimicrobial activity of AI-EVDs dropped quickly in vivo. Antimicrobial impregnation did not prevent AI-EVD colonization by susceptible strains in 9% of the cases.

Peripheral white blood cell count as a screening tool for ventriculostomy-related infections

One of the most common complications following external ventricular drain (EVD) placement is infection. Routine cultures of cerebrospinal fluid (CSF) are often used to screen for infection, however several days may pass before infection is discovered. In this study, we compared the predictive value of daily recorded vital sign parameters and peripheral white blood count (WBC) in identifying ventriculostomy-related infections. Patients with EVDs who had CSF cultures for microorganisms performed between January 2011 and July 2017 were assigned to either an infected and/or uninfected study group. Clinical parameters were then compared using t-test, chi squared and multiple logistic regression analyses. Patients of any age and gender were included. One hundred seventy uninfected and 10 infected subjects were included in the study. Nine of the 10 infected patients had an elevated WBC (>10.4 × 10³/μL), with a significantly greater WBC (15.9 × 10³/μL) than the uninfected group (10.4 × 10³/μL) (p-value ≤ 0.0001). Using logistic regression, we found no association between patient vital signs and CSF infection except for WBC (p = .003). As a diagnostic marker for CSF infection, the sensitivity and specificity of WBC elevation greater than 15 × 10³/μL was 70% (7/10) and 90.2% (147/163), respectively. This study serves as a 'proof of concept' that WBC could be useful as potential screening tool for early detection of CSF infection post-EVD placement. Future investigation using a large, multicenter prospective study is needed to further assess the applicability of this parameter.

The SiLuDrain Trial: a prospective randomized controlled trial comparing standard versus silver-impregnated lumbar drains

OBJECTIVE

Catheter-associated cerebrospinal fluid (CSF) infection remains a serious event, especially for patients in neurocritical care units. The use of external ventricular drain (EVD) catheters impregnated with antimicrobial substances has led to a significant reduction of infection rates. This study was undertaken to compare the use of antimicrobial, silver-impregnated external lumbar drains (si-ELDs) and conventional ELDs.

METHODS

Patients with an indication for ELD placement were randomized to receive either a conventional or an si-ELD catheter. Regular assessment for CSF infections and device-related complications was performed. Neurosurgeons placing the ELD rated the usability and handling of the catheter on a 6-item ordinal performance scale (range: 1, very bad, to 5, very good). All microorganisms isolated in this study were tested for silver-susceptibility via a catheter-roll method.

RESULTS

A total of 48 patients were enrolled in the trial. The si-ELD catheters showed a nonsignificantly lower infection rate compared to conventional ones (4.2% vs 16.7%, p = 0.16). The majority of infections were caused by Staphylococcus species. Device-related complications occurred significantly less often with silver-impregnated-catheters than with conventional ones (8.3% vs 37.5%, p = 0.02). The usability was rated significantly better for si-ELDs (p = 0.003). Antimicrobial susceptibility was shown for si-ELDs against various Staphylococcus spp., but Candida parapsilosis and Escherichia coli were not affected by this antimicrobial agent.

CONCLUSIONS

Silver-impregnated ELD catheters, which could potentially reduce the number of CSF infections, show significantly better properties in regard to handling and fewer device-related complications. Whether they are superior to antibiotic-impregnated catheters or a clinical regimen involving antibiotic prophylaxis remains to be proven.Clinical trial registration no.: DRKS00013513 (Deutsches Register Klinischer Studien).

Patterns of Health Care Costs Due to External Ventricular Drain Infections

BACKGROUND

External ventricular drain (EVD) infections are a significant cause of morbidity among neurosurgical patients and have been correlated with increased length of hospital stay and longer requirements for intensive care. To date, no studies have examined the financial impact of EVD infections.

METHODS

Patients who underwent EVD placement between December 2010 and January 2016 were included in the study. Clinical records were retrospectively reviewed and health care cost data were obtained from the hospital's finance department. Clinical information included patient demographics, details from the hospital course, and outcomes. Total costs, direct/indirect, and fixed/variable costs were analyzed for every patient.

RESULTS

Over the 5-year study period, 246 EVDs were placed in 243 patients with an overall infection rate of 9.9% (N = 24). The median EVD duration for infected versus noninfected patients was 19 and 9 days, respectively (P < 0.0001). Median length of intensive care unit stay also was increased for patients with EVD infection (30 days vs. 13 days, P < 0.0001). Total health care costs were significantly greater for infected patients (US$ 168,692 vs. US$ 83,919, P < 0.0001). This trend was comparable for all other cost subtypes, including fixed-direct costs, fixed-indirect costs, variable direct costs, and variable-indirect costs.

CONCLUSIONS

EVD infection has a substantial effect on clinical morbidity and healthcare costs. These results demonstrate the imperative need to improve EVD infection prevention, particularly in the setting of a value-based health care system.

Risk Factors of External Ventricular Drain Infection: Proposing a Model for Future Studies

Background: External ventricular drain (EVD) has a major role in the management and monitoring of intracranial pressure (ICP) and its major complication is EVD infection. The risk factors for EVD infection are still a major topic of controversy, hence the need for further research.

Objective: The objective of this review was to identify risk factors that affect the incidence of EVD infection and create a model, which can be used in future studies in order to contribute to elaborations on guideline for EVD.

Methods: A PubMed and Google Scholar literature search was performed and data were extracted from studies published from 1966 through 2017. The search of the databases generated 604 articles and 28 articles of these were found to be relevant. A manual search of the 28 relevant papers generated 4 new articles. Of the 32 relevant articles, 20 articles that performed a multivariate analysis of the suspected risk factors of EVD infection and had a positive culture as a mandatory component in diagnosis were selected for data collection and analysis.

Results: Because reviewed papers investigated only a few influencing factors, and could not determine convincingly the real risk factors of EVD infection and their real strengths. A total of 15 supposed influencing factors which includes: age, age & sex interactions, coinfection, catheter insertion outside the hospital, catheter type, CSF leakage, CSF sampling frequency, diagnosis, duration of catheterization, ICP > 20 mmHg, irrigation, multiple catheter, neurosurgical operation, reduced CSF glucose at catheter insertion and sex were identified.

Conclusion: This review summarizes a set of variables which have to be covered by future clinical epidemiological investigations in order to describe the etiological background of EVD infection.

Retrospective Analysis of Ventriculitis in External Ventricular Drains

Background

Nosocomial EVD-related ventriculitis is a major complication and a significant cause of morbidity and mortality in critically ill neurological patients. Questions remain about best management of EVDs. The purpose of this study is to compare our incidence of ventriculitis to studies using different catheters and/or antibiotic coverage schemes and determine whether c-EVD with prolonged antibiotics given for the duration of drain placement is inferior to ac-EVD with pp-abx or ac-EVD with prolonged antibiotics for prevention of ventriculitis.

Methods

A retrospective chart review of all patients who had EVDs placed from January 2010 through December 2015 at home institution was performed. Statistical analysis was performed using Fisher's exact test to compare incidence of ventriculitis identified in other studies with that of home institution.

Results

The study included 107 patients, 66 (61.7%) males and 41 (38.3%) females. Average age was 56 years ranging from 18 to 95 years. Average length of drain placement was 7.8 days ranging from 2 to 23 days. Average length of drain placement in infected drains was 13.3 days ranging from 11 to 15 days. There were 3 cases with positive CSF cultures (Staphylococcus haemolyticus and Staphylococcus epidermidis x 2). There were 2 cases with a CSF having a positive gram stain but failed to yield any bacterial growth on culture and did not meet predefined criteria.

Conclusions

The c-EVD with prolonged antibiotics given for the duration of drain placement is not inferior to ac-EVD with pp-abx or ac-EVD with prolonged antibiotics for prevention of ventriculitis. The c-EVD with prolonged antibiotics is superior to c-EVD with pp-abx and conventional EVD without antibiotics for prevention of ventriculitis. Selection should include considerations for antibiotic stewardship and cost effectiveness. Future studies should also utilize clinical and CSF profile criteria in addition to positive CSF cultures for identifying ventriculitis to prevent line colonization from classification as ventriculitis in analysis.

Applicability, Safety, and Cost-Effectiveness of Improvised External Ventricular Drainage: An Observational Study of Tunisian Neurosurgery Inpatients

OBJECTIVE

External ventricular drainage (EVD) is an emergent neurosurgical procedure. Many commercial sets are available for EVD that are not always obtainable in all hospitals. The aim of our study was to describe new techniques to perform EVD using simple improvised materials to check the real-world applicability of the same device in the management of acute hydrocephalus and its effectiveness and safety.

METHODS

We illustrated 2 techniques for a "do it yourself" improvised EVD device using materials available even in non-neurosurgery-dedicated operating rooms. We performed an observational study in our institution (April 2015 to December 2016). We included all patients presenting with acute hydrocephalus and requiring EVD.

RESULTS

During a 20-month period, the new EVD device was used as a lifesaving solution for 33 patients. Good outcomes were noted in 11 of the 33 patients (33%). The EVD was complicated by fatal meningitis in 4 of the patients (12%). Malfunction occurred in 6 patients. The new EVD device costs less than US$20 for the first technique and less than US$10 for the second technique. In contrast, the cost of a standard EVD set ranges from US$170 to US$380 in Tunisia.

CONCLUSIONS

The new EVD device has the potential to improve the quality of efficiency of care in difficult economic times that have changed the medical landscape, because it is both easy to make and cost-effective. Because it is an inexpensive technique, it could also be suitable for low-income countries, where neurosurgery is not yet the first and foremost health priority.

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.

Recurrent sampling and ventriculostomy-associated infections: a case-control study

BACKGROUND

External ventricular drain (EVD) insertion is a common neurosurgical procedure with a significant risk of ventriculostomy-associated infections (VAIs), other morbidities and mortality. Several risk factors have been identified but their effect is unclear.

OBJECTIVE

Our primary objective was to assess whether recurrent EVD sampling increased the risk of VAIs. The secondary objective was to explore the effect of sampling frequency, duration of EVD stay, presence of cerebrospinal fluid leak and concurrent infections.

METHODS

Ours was a retrospective, single-centre, age-matched, case control study of 83 patients and 249 controls who underwent EVD insertion between 1 January 2010 - 31 December 2016. Patients with primary CNS infections, age under 1 year and death within 5 days of EVD insertion were excluded. Blinded abstractors collected all patient data through the electronic patient record system and regression analysis was used to compare the two groups.

RESULTS

Sampling the EVD more than once did not increase the risk of infection (OR 0.47, 95% CI 0.27-0.83, p = 0.01). Risk factors significantly associated with VAI included CSF leak (OR 2.06, 95% CI 1.16-3.67, p = 0.01), concurrent infection (OR 1.85, 95% CI 1.09-3.16, p = 0.02), and an EVD duration of >10 days (OR 2.28, 95% CI 1.24-4.18, p = 0.01).

CONCLUSION

Our findings do not support the notion that increased sampling of EVDs is associated with a higher risk of VAI. CSF leaks, concurrent infection and long-term EVDs are also statistically significant risk factors for infection.

Topical vancomycin reduces the cerebrospinal fluid shunt infection rate: A retrospective cohort study

Object

Despite many efforts at reduction, cerebrospinal fluid (CSF) shunt infections are a major cause of morbidity in shunt surgery, occurring in 5–15% of cases. To attempt to reduce the shunt infection rate at our institution, we added topical vancomycin (intrashunt and perishunt) to our existing shunt infection prevention protocol in 2012.

Methods

We performed a retrospective cohort study comparing all shunted patients in January 2010 to December 2011 without vancomycin (control group, 263 procedures) to all patients who underwent shunt surgery between April 2012 and December 2015 with vancomycin (intervention group, 499 procedures).

Results

The overall shunt infection rate significantly decreased from 6.8% (control group) to 3.0% (intervention group) (p = 0.023, absolute risk reduction 3.8%, relative risk reduction 56%). Multivariate logistic regression analysis confirmed that the addition of topical vancomycin showed that cases treated under a protocol of topical vancomycin were associated with a decreased shunt infection rate (odds ratio [OR] 0.49 95% CI 0.25–0.998; p = 0.049). Age < 1 year was associated with an increased risk of infection (OR) 4.41, 95% CI 2,10–9,26; p = 0.001). Time from surgery to infection was significantly prolonged in the intervention group (p = 0.001).

Conclusion

Adding intraoperative vancomycin to a shunt infection prevention protocol significantly reduces CSF shunt infection rate.