Perioperative Management of Adult Patients With External Ventricular and Lumbar Drains: Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care

Inadvertent administration of intravenous anaesthesia induction agents via the intracerebroventricular, neuraxial or peripheral nerve route - A narrative review

Intravenous (IV) medication administration error remains a major concern during the perioperative period. This review examines inadvertent IV anaesthesia induction agent administration via high-risk routes. Using Medline and Google Scholar, the author searched published reports of inadvertent administration via neuraxial (intrathecal, epidural), peripheral nerve or plexus or intracerebroventricular (ICV) route. The author applied the Human Factors Analysis and Classification System (HFACS) framework to identify systemic and human factors. Among 14 patients involved, thiopentone was administered via the epidural route in six patients. Four errors involved the routes of ICV (propofol and etomidate one each) or lumbar intrathecal (propofol infusion and etomidate bolus). Intrathecal thiopentone was associated with cauda equina syndrome in one patient. HFACS identified suboptimal handling of external ventricular and lumbar drains and deficiencies in the transition of care. Organisational policy to improve the handling of neuraxial devices, use of technological tools and improvements in identified deficiencies in preconditions before drug preparation and administration may minimise future risks of inadvertent IV induction agent administration.

A Pathophysiological Approach to Spontaneous Orbital Meningoceles: Case Report and Systematic Review

BACKGROUND

Spontaneous orbital cephaloceles are a rare condition. The purpose of this study is to provide a description of a clinical case and to carry out a systematic literature review.

METHODS

A systematic review of the English literature published on the Pubmed, Scopus, and Web of Science databases was conducted, according to the PRISMA recommendations.

RESULTS

A 6-year-old patient was admitted for right otomastoiditis and thrombosis of the sigmoid and transverse sinuses, as well as the proximal portion of the internal jugular vein. Radiological examinations revealed a left orbital mass (22 × 14 mm) compatible with asymptomatic orbital meningocele (MC) herniated from the superior orbital fissure (SOF). The child underwent a right mastoidectomy. After the development of symptoms and signs of intracranial hypertension (ICH), endovascular thrombectomy and transverse sinus stenting were performed, with improvement of the clinical conditions and reduction of the orbital MC. The systematic literature review encompassed 29 publications on 43 patients with spontaneous orbital MC. In the majority of cases, surgery was the preferred treatment.

CONCLUSIONS

The present case report and systematic review highlight the importance of ICH investigation and a pathophysiological-oriented treatment approach. The experiences described in the literature are limited, making the collection of additional data paramount.

Clinical Experience With a Dedicated Neurocritical Care Quality Improvement Program in an Academic Medical Center

Background Managing neurocritical care patients encompasses many complex challenges, necessitating specialized care and continuous quality improvement efforts. In recent years, the focus on enhancing patient outcomes in neurocritical care may have led to the development of dedicated quality improvement programs. These programs are designed to systematically evaluate and refine care practices, aligning them with the latest clinical guidelines and research findings. Objective To describe the structure, processes, and outcomes of a dedicated Neurocritical Care Quality Improvement Program (NCC-QIP) at Harborview Medical Center, United States; a quaternary academic medical center, level I trauma, and a comprehensive stroke center. Materials and methods We describe the development of the NCC-QIP, its structure, function, challenges, and evolution. We examine our performance with several NCC-QI quality measures as proposed by the Joint Commission, the American Association of Neurology, and the Neurocritical Care Society, self-reported quality improvement (QI) concerns and QI initiatives undertaken because of the information obtained during our event/measure reporting process for patients admitted between 1/1/2014 and 06/30/2023. Results The NCC-QI reviewed data from 20,218 patients; mean age 57.9 (standard deviation 18.1) years, 56% (n=11,326) males, with acute ischemic stroke (AIS; 22.3%, n=4506), spontaneous intracerebral hemorrhage (ICH; 14.8%, n=2,996), spontaneous subarachnoid hemorrhage (SAH; 8.9%, n=1804), and traumatic brain injury (TBI; 16.6%, n=3352) among other admissions, 37.4% (n=7,559) were mechanically ventilated, and 13.6% (n=2,753) received an intracranial pressure monitor. The median intensive care unit length of stay was two days (Quartile 1-Quartile 3: 2-5 days), and the median hospital length of stay was seven days (Quartile 1-Quartile 3: 3-14 days); 53.9% (n=10,907) were discharged home while 11.4% (2,309) died. The three most commonly reported QI concerns were related to care coordination/communication/handoff (40.4%, n=283), medication-related concerns (14.9%, n=104), and equipment/devices-related concerns (11.7%, n=82). Hospital-acquired infections were in the form of ventilator-associated pneumonia (16.3%, n=419/2562), ventriculostomy catheter-associated infections (4%, n=102/2246), and deep venous thrombosis/pulmonary embolism (3.2%, n=647). The quality metrics documentation was as follows: nimodipine after SAH (99.8%, 1802/1810), Hunt and Hess score (36%, n=650/1804), and ICH score (58.4% n=1752/2996). In comparison, 72% (n=3244/4506) of patients with AIS had a documented National Institute of Health Stroke Scale. Admission Glasgow Coma Score was recorded in 99% of patients with SAH, ICH, and TBI. Educational modules were implemented in response to event reporting. Conclusion A dedicated NCC-QIP can be successfully implemented at a quaternary medical medical center. It is possible to monitor and review a large volume of neurocritical care patients, The three most reported NCC-QI concerns may be related to care coordination-communication/handoff, medication-related concerns, and equipment/devices-related complications. The documentation of illness severity scores and stroke measures depends upon the type of measure and ability to reliably and accurately abstract and can be challenging. The quality improvement process can be enhanced by educational modules that reinforce quality and safety.

Invasive Pressure Monitors: Leveling the Playing Field

Invasive pressure monitors are ubiquitous in cardiothoracic and vascular anesthesia. This technology allows beat-to-beat assessment of central venous, pulmonary, and arterial blood pressures during surgery, procedural interventions, and critical care. Education is commonly focused on the procedural aspects and the complications associated with the initial placement of these monitors without instruction on the technical concepts required for obtaining accurate data. Anesthesiologists must understand the fundamental concepts on which measurements are made to effectively use invasive pressure monitors, including pulmonary artery catheters, central venous catheters, intra-arterial catheters, external ventricular drains, and spinal or lumbar drains. This review will address important gaps in knowledge surrounding leveling and zeroing of invasive pressure monitors, emphasizing the impact of varied practice patterns on patient care.

Zeroing a Transducer on an External Ventricular Drain

ABSTRACT

BACKGROUND: External ventricular drains (EVDs) are commonly used in severely brain-injured patients to diagnose intracranial hypertension. The accuracy of the intracranial pressure reading is dependent on zeroing the external transducer to air. Recent concern about zeroing techniques has been identified in the neuroscience community. The open method requires removing the nonvented cap, and the closed method requires zeroing through the filter at the top of the burette. This critical appraisal seeks to explore whether zeroing a transducer on an EVD through the filter of the burette provides the same baseline zero as opening the transducer to air. METHODS: Independent searches in CINAHL, PubMed, and Web of Science were conducted using "external ventricular drain* OR EVD AND transducer"; secondary search terms included "zero AND transducer" AND "ventric." RESULTS: Database search produced 1 single observation study and 2 clinical practice guidelines from neuroscience professional organizations. The single observation study provided no evidence of equivalence between the 2 zeroing methods; the 2 clinical practice guidelines reference the open method. The transducer manufacturer's instructions for use direct the clinician to open the transducer to air by removing the nonvented cap. CONCLUSION: The question "Does zeroing the transducer on an EVD through the filter of the burette provide the same baseline zero as opening the transducer to air?" cannot be answered with the results of this appraisal. However, evidence found in the literature does suggest an open method to ensure the most accurate physiological value for treatment decisions.

Implementation of an Online External Ventricular Drain Training Module-An Educational Initiative to Improve Proficiency of Perioperative Health Care Providers: Results of a Retrospective Study

BACKGROUND

An external ventricular drain (EVD) training module may improve the knowledge and proficiency of perioperative health care providers (HCPs).

METHODS

We examined knowledge gaps, self-reported comfort in managing EVDs, and improvement in self-assessment scores among HCPs from 7 academic medical centers based on an online EVD training module.

RESULTS

Of the 326 HCPs who completed the module, 207 (70.6%) reported being uncomfortable managing EVDs. The median pretest scores were 6 (interquartile range=2), and posttest scores were 8 (interquartile range=1), out of a maximum possible score of 9. The most frequent incorrectly answered questions were: (a) maximum allowed hourly cerebrospinal fluid volume drainage (51%), (b) the components of a normal intracranial pressure waveform (41%), and (c) identifying the correct position of the stopcock for accurate measurement of intracranial pressure (41%). The overall gain in scores was 2 (interquartile range=2) and highest among HCPs who had managed 1 to 25 EVDs (2.51, 95% confidence interval: 2.23-2.80), and without self-reported comfort in managing EVDs (2.26, 95% confidence interval: 1.96-2.33, P <0.0001). The majority of participants (312, 95.7%) reported that the training module helped them understand how to manage EVDs, and 276 (84.7%) rated the module 8 or more out of 10 in recommending it to their colleagues.

CONCLUSIONS

This online EVD training module was well-received by participants. Overall, improved scores reflect enhanced knowledge among HCPs following completion of the module. The greatest benefit was observed in those reporting less experience and feeling uncomfortable in managing EVDs. The impact on the reduction in EVD-associated adverse events deserves further examination.

Traumatic Brain Injury: Intraoperative Management and Intensive Care Unit Multimodality Monitoring

Traumatic brain injury is a devastating event associated with substantial morbidity. Pathophysiology involves the initial trauma, subsequent inflammatory response, and secondary insults, which worsen brain injury severity. Management entails cardiopulmonary stabilization and diagnostic imaging with targeted interventions, such as decompressive hemicraniectomy, intracranial monitors or drains, and pharmacological agents to reduce intracranial pressure. Anesthesia and intensive care requires control of multiple physiologic variables and evidence-based practices to reduce secondary brain injury. Advances in biomedical engineering have enhanced assessments of cerebral oxygenation, pressure, metabolism, blood flow, and autoregulation. Many centers employ multimodality neuromonitoring for targeted therapies with the hope to improve recovery.

The Impact of Nursing Education on Emergency Bedside External Ventricular Drain Insertion for Patients With Acute Hydrocephalus

Objectives Acute hydrocephalus is a neurosurgical emergency that requires immediate intervention. With emergency external ventricular drain (EVD) insertion and management, such rapid intervention can be a safe bedside procedure. Nurses play an integral role in patient management. Thus, this study aims to assess the knowledge, attitudes, and practices of nurses from different departments regarding bedside EVD insertion in patients with acute hydrocephalus. Methods EVD and intracranial pressure (ICP) monitoring competency checklists were developed, and a quasi-experimental, single-group, pre/post-test study was conducted at a university hospital in Jeddah, Saudi Arabia, in January 2018 during an educational program. The neurosurgery team determined program efficacy using pre/post-questionnaires. All attendees who agreed to fill in the pre- and post-survey and whose data were complete were included in the study. Results Of the 140 nurses who participated in the study, the data of 101 were analyzed. Knowledge level improved significantly between the pre- and post-test; for example, when asked about administering antibiotics before EVD insertion, the pre-test correct response rate of 65% increased to 94% in the post-test (p<0.001), and 98% considered the session informative. However, the attitude toward bedside EVD insertion did not change after the teaching sessions. Conclusion This study emphasizes the importance of ongoing nursing education, hands-on training, and strict adherence to an EVD insertion checklist to achieve successful bedside management of patients with acute hydrocephalus.

Reducing External Ventricular Drain (EVD) Associated Ventriculitis: An improvement project in a Level 1 Trauma Center

BACKGROUND

External ventricular drain (EVD)-associated infections have a negative impact on healthcare cost and patient outcomes. Practice variation in EVD management may place patients at increased risk for EVD-associated infection. This project aimed to evaluate the impact of implementing an interprofessional evidence-based EVD bundle of care on reduction of EVD-related ventriculitis rates.

METHODS

An interprofessional team developed an evidence based EVD care bundle and order set to eliminate practice inconsistencies. Standardization of EVD equipment and optimization of the electronic health record occurred. Education and competency validation were completed with neurosurgical providers and nurses. Interprofessional rounds occur weekly for observation, recognition, and in-the-moment education.

RESULTS

A pre/post intervention design was used to show that the rate of EVD-associated ventriculitis decreased from 8.8 per reported EVD days in 2019 to 0 per reported EVD days in 2021 after implementation of the EVD care bundle.

CONCLUSION

Through an interprofessional team approach, reduction in EVD-associated infection rates is feasible with implementation of an evidence based EVD care bundle.

Prediction of Lumbar Drainage-Related Meningitis Based on Supervised Machine Learning Algorithms

Background

Lumbar drainage is widely used in the clinic; however, forecasting lumbar drainage-related meningitis (LDRM) is limited. We aimed to establish prediction models using supervised machine learning (ML) algorithms.

Methods

We utilized a cohort of 273 eligible lumbar drainage cases. Data were preprocessed and split into training and testing sets. Optimal hyper-parameters were archived by 10-fold cross-validation and grid search. The support vector machine (SVM), random forest (RF), and artificial neural network (ANN) were adopted for model training. The area under the operating characteristic curve (AUROC) and precision-recall curve (AUPRC), true positive ratio (TPR), true negative ratio (TNR), specificity, sensitivity, accuracy, and kappa coefficient were used for model evaluation. All trained models were internally validated. The importance of features was also analyzed.

Results

In the training set, all the models had AUROC exceeding 0.8. SVM and the RF models had an AUPRC of more than 0.6, but the ANN model had an unexpectedly low AUPRC (0.380). The RF and ANN models revealed similar TPR, whereas the ANN model had a higher TNR and demonstrated better specificity, sensitivity, accuracy, and kappa efficiency. In the testing set, most performance indicators of established models decreased. However, the RF and AVM models maintained adequate AUROC (0.828 vs. 0.719) and AUPRC (0.413 vs. 0.520), and the RF model also had better TPR, specificity, sensitivity, accuracy, and kappa efficiency. Site leakage showed the most considerable mean decrease in accuracy.

Conclusions

The RF and SVM models could predict LDRM, in which the RF model owned the best performance, and site leakage was the most meaningful predictor.

Combined ultrasound and fluoroscopy guided tunneled external lumbar drain placement in children

External lumbar drain placement has been shown to be an efficacious and safe approach to managing various forms of intracranial hypertension in adult patients and children. The use of ultrasound guidance for lumbar punctures in young patients has been described however, but the modality is not routinely used for the placement of tunneled lumbar drains. In this report, two cases are presented that detail experience using ultrasound guidance for tunneled lumbar drains in children.

Quality Indicators Targeting Low-Value Clinical Practices in Trauma Care

Importance

The use of quality indicators has been shown to improve injury care processes and outcomes. However, trauma quality indicators proposed to date exclusively target the underuse of recommended practices. Initiatives such as Choosing Wisely publish lists of practices to be questioned, but few apply to trauma care, and most have not successfully been translated to quality indicators.

Objective

To develop a set of evidence and patient-informed, consensus-based quality indicators targeting reductions in low-value clinical practices in acute, in-hospital trauma care.

Design, Setting, and Participants

This 2-round Research and Development/University of California at Los Angeles (RAND/UCLA) consensus study, conducted from April 20 to June 9, 2021, comprised an online questionnaire and a virtual workshop led by 2 independent moderators. Two panels of international experts from Canada, Australia, the US, and the UK, and local stakeholders from Québec, Canada, represented key clinical expertise involved in trauma care and included 3 patient partners.

Main Outcomes and Measures

Panelists were asked to rate 50 practices on a 7-point Likert scale according to 4 quality indicator criteria: importance, supporting evidence, actionability, and measurability.

Results

Of 49 eligible experts approached, 46 (94%; 18 experts [39%] aged ≥50 years; 37 men [80%]) completed at least 1 round and 36 (73%) completed both rounds. Eleven quality indicators were selected overall, 2 more were selected by the international panel and a further 3 by the local stakeholder panel. Selected indicators targeted low-value clinical practices in the following aspects of trauma care: (1) initial diagnostic imaging (head, cervical spine, ankle, and pelvis), (2) repeated diagnostic imaging (posttransfer computed tomography [CT] and repeated head CT), (3) consultation (neurosurgical and spine), (4) surgery (penetrating neck injury), (5) blood product administration, (6) medication (antibiotic prophylaxis and late seizure prophylaxis), (7) trauma service admission (blunt abdominal trauma), (8) intensive care unit admission (mild complicated traumatic brain injury), and (9) routine blood work (minor orthopedic surgery).

Conclusions and Relevance

In this consensus study, a set of consensus-based quality indicators were developed that were informed by the best available evidence and patient priorities, targeting low-value trauma care. Selected indicators represented a trauma-specific list of practices, the use of which should be questioned. Trauma quality programs in high-income countries may use these study results as a basis to select context-specific quality indicators to measure and reduce low-value care.

Single Plasma Unit Transfusions in Adults Are Either Unnecessary or Underdosed

OBJECTIVES

Previous studies of blood product use have shown higher inappropriate use of plasma compared with other products. Given typical weight-based dosing of plasma, we hypothesized that single plasma transfusions in adults would either be a nontherapeutic dose or outside clinical guidelines.

METHODS

A single-center, retrospective review of nonoperative, nonapheresis plasma use was conducted from January 2020 to April 2020. Plasma transfusions were reviewed for compliance with clinical guidelines formulated at our institution as well as national and society guidelines.

RESULTS

During the study period, 313 units of plasma were transfused. Of these, 152 (48.6%) were given against institutional or national guidelines, 126 plasma units (40.3%) were transfused as single units, and 187 (59.7%) were given as part of multiple-unit transfusions. All single-unit plasma transfusions during the study period were either underdosed or outside clinical guidelines. Units transfused with an indication of "Other" were significantly more likely to be outside clinical guidelines.

CONCLUSIONS

Nonoperative, nonapheresis plasma use is often outside clinical guidelines. Single-unit plasma transfusions in adults are a potential target for patient blood management programs seeking to minimize unnecessary plasma use.

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

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

The pressure differential efflux technique - A novel approach for troubleshooting air-locked external ventricular drainage systems: A technical note and review of literature

External ventricular drainage (EVD) is carried out in many neurosurgical conditions for the diversion of cerebrospinal fluid. These EVD systems can, however, malfunction with potentially lethal consequences. Air bubbles within the EVD can result in air locking of the system with subsequent blockage of drainage, with blood clots and debris being the other causes. There are both non-invasive and invasive methods of rectifying such blockages, with invasive procedures having its associated risks. This is especially so for EVD revisions, with each surgery increasing the risk of ventriculitis. We describe a case of bilateral air locked EVD managed successfully with a novel non-invasive 'pressure differential efflux technique'. This method exploits the pressure gradient established by adjusting each EVD to a different height to evacuate the pneumoventricle. In addition, we present a sequential approach to the management of EVD malfunction, based on the current literature and our institutional protocol.

Guidelines on the use of external ventricular drain and its associated complications: do we "AGREE II"?

Insertion of an external ventricular drain is a common procedure used in everyday practice by neurosurgeons all around the world. It consists of the placement of an external ventricular drain (EVD) into the ventricular system providing the ability to measure intracranial pressure, and also divert the flow of cerebrospinal fluid (CSF) in a variety of pathological conditions. The most common complication is infection, and it may result in devastating consequences and negatively affect the outcome of these patients. The Infectious Diseases Society of America (IDSA), the Neurocritical Care Society (NCS), and The Society for Neuroscience in Anesthesiology & Critical Care (SNACC) have published recommendations for the management of EVD-Associated Ventriculitis. The objective of this study was to assess the methodological quality and reporting clarity of these recommendations using the AGREE-II tool. We found that the overall quality of the published clinical practice guidelines is acceptable. However, continuous updates and external validation should be implemented.

Levels of Evidence Supporting the North American and European Perioperative Care Guidelines for Anesthesiologists between 2010 and 2020: A Systematic Review

BACKGROUND

Although there are thousands of published recommendations in anesthesiology clinical practice guidelines, the extent to which these are supported by high levels of evidence is not known. This study hypothesized that most recommendations in clinical practice guidelines are supported by a low level of evidence.

METHODS

A registered (Prospero CRD42020202932) systematic review was conducted of anesthesia evidence-based recommendations from the major North American and European anesthesiology societies between January 2010 and September 2020 in PubMed and EMBASE. The level of evidence A, B, or C and the strength of recommendation (strong or weak) for each recommendation was mapped using the American College of Cardiology/American Heart Association classification system or the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The outcome of interest was the proportion of recommendations supported by levels of evidence A, B, and C. Changes in the level of evidence over time were examined. Risk of bias was assessed using Appraisal of Guidelines for Research and Evaluation (AGREE) II.

RESULTS

In total, 60 guidelines comprising 2,280 recommendations were reviewed. Level of evidence A supported 16% (363 of 2,280) of total recommendations and 19% (288 of 1,506) of strong recommendations. Level of evidence C supported 51% (1,160 of 2,280) of all recommendations and 50% (756 of 1,506) of strong recommendations. Of all the guidelines, 73% (44 of 60) had a low risk of bias. The proportion of recommendations supported by level of evidence A versus level of evidence C (relative risk ratio, 0.93; 95% CI, 0.18 to 4.74; P = 0.933) or level of evidence B versus level of evidence C (relative risk ratio, 1.63; 95% CI, 0.72 to 3.72; P = 0.243) did not increase in guidelines that were revised. Year of publication was also not associated with increases in the proportion of recommendations supported by level of evidence A (relative risk ratio, 1.07; 95% CI, 0.93 to 1.23; P = 0.340) or level of evidence B (relative risk ratio, 1.05; 95% CI, 0.96 to 1.15; P = 0.283) compared to level of evidence C.

CONCLUSIONS

Half of the recommendations in anesthesiology clinical practice guidelines are based on a low level of evidence, and this did not change over time. These findings highlight the need for additional efforts to increase the quality of evidence used to guide decision-making in anesthesiology.

EDITOR’S PERSPECTIVE

Ultrasound as a Useful Tool in Hydrocephalus Management During Pregnancy: A Case Report

A 38-year-old pregnant woman in her 24th week of gestation was admitted to our neurosurgical intensive care unit with a 5-cm cerebellar hemangioblastoma and acute hydrocephalus. Initial management included the placement of an external ventricular drain to prevent neurological deterioration. Five days after the initial diagnosis, the patient successfully underwent a neurosurgical intervention to remove the lesion. Transcranial ultrasound was used to determine the optimal ventricular drain level and facilitate weaning, bypassing the need for cerebral computed tomography and cerebral magnetic resonance imaging, which would have otherwise been necessary in postoperative follow-up.

Decreasing External Ventricular Drain Infection Rates in the Neurocritical Care Unit: 12-Year Longitudinal Experience at a Single Institution

OBJECTIVE

External ventricular drain (EVD) placement is a common neurosurgical procedure, and EVD-related infection is a significant complication. We examined the effect of infection control protocol changes on EVD-related infection incidence.

METHODS

Changes in EVD placement protocol and incidence density of infections after implementation of protocol changes in the neurocritical care unit were tracked from 2007 to 2019. EVD infections were defined using a modified U.S. Centers for Disease Control and Prevention National Healthcare Safety Network surveillance definition of meningitis/ventriculitis for patients with EVDs in situ for at least 2 days confirmed by positive culture. Contribution of protocol changes to EVD infection risk was assessed via multivariate regression.

RESULTS

Fifteen major changes in EVD protocol were associated with a reduction in infections from 6.7 to 2.0 per 1000 EVD days (95% confidence interval [CI], 4.1-5.3; P < 0.001). Gram-positive bacterial infection incidence decreased from 4.8 to 1.7 per 1000 EVD days (95% CI, 2.3-3.9; P = 0.00882) and gram-negative infection incidence decreased from 1.9 to 0.5 per 1000 EVD days (95% CI, 0.6-2.3; P = 0.0303). Of all protocol changes since 2007, the largest reduction in incidence was 3.9 infections per 1000 days (95% CI, 0.50-7.30; P = 0.011), associated with combined standardization of reduced EVD sampling frequency, cutaneous antisepsis with alcoholic chlorhexidine before EVD placement, and use of a subcutaneous tunneling technique during EVD insertion.

CONCLUSIONS

The most significant reduction in EVD infections may be achieved through the combination of reducing EVD sampling frequency and standardizing alcoholic chlorhexidine cutaneous antisepsis and subcutaneous tunneling of the EVD catheter.

Neuroanesthesiology Update

This review summarizes the literature published in 2020 that is relevant to the perioperative care of neurosurgical patients and patients with neurological diseases as well as critically ill patients with neurological diseases. Broad topics include general perioperative neuroscientific considerations, stroke, traumatic brain injury, monitoring, anesthetic neurotoxicity, and perioperative disorders of cognitive function.

Lumbar drains: Practical understanding and application for the otolaryngologist

INTRODUCTION

Lumbar drains are frequently used in patients with otolaryngologic concerns. These can be used therapeutically or prophylactically with the primary purpose being to modulate CSF pressure. Within otolaryngology, lumbar drains are most frequently used for cerebrospinal fluid leaks - either due to cerebrospinal fluid fistulas or in skull base surgery as these allow for potential healing of the defect. While not typically placed by otolaryngologists, a basic understanding of lumbar drains is beneficial in the context of patient management.

MANAGEMENT

A lumbar drain is inserted into the intrathecal space in a patient's lumbar spine. Though considered to be a benign procedure, complications are relatively frequent, and adjustment or replacement of the drain may be required. Complications include infection, epidural bleeding, retained hardware, sequelae of relative immobility, or may relate to over-drainage, ranging from mild headache to cranial neuropathies, altered mental status, pneumocephalus, intracranial hemorrhage, and death. While in place, neurologic exams should be performed routinely and should include motor and sensory exams of the lower extremities. A patient should be monitored for fevers, nuchal rigidity, and other signs of infection or meningitis. The CSF fluid should be grossly examined to identify changes, but routine laboratory tests are not typically run on the fluid itself. Drainage rates will vary usually between 5 and 20 mL per hour and must be frequently reassessed and adjusted based upon signs of intracranial hypotension. Drains should be removed when appropriate and should not be left in more than 5 days due to the increased infectious risk.

CONCLUSION

Lumbar drains are important tools used in patients with otolaryngologic pathologies. Otolaryngologists and otolaryngology residents should be familiar with these catheters to determine if they are working correctly and to identify adverse effects as early as possible.

Perioperative Management of Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage is an acute neurologic emergency. Prompt definitive treatment of the aneurysm by craniotomy and clipping or endovascular intervention with coils and/or stents is needed to prevent rebleeding. Extracranial manifestations of aneurysmal subarachnoid hemorrhage include cardiac dysfunction, neurogenic pulmonary edema, fluid and electrolyte imbalances, and hyperglycemia. Data on the impact of anesthesia on long-term neurologic outcomes of aneurysmal subarachnoid hemorrhage do not exist. Perioperative management should therefore focus on optimizing systemic physiology, facilitating timely definitive treatment, and selecting an anesthetic technique based on patient characteristics, severity of aneurysmal subarachnoid hemorrhage, and the planned intervention and monitoring. Anesthesiologists should be familiar with evoked potential monitoring, electroencephalographic burst suppression, temporary clipping, management of external ventricular drains, adenosine-induced cardiac standstill, and rapid ventricular pacing to effectively care for these patients.

Prolonged infusion of linezolid is associated with improved pharmacokinetic/pharmacodynamic (PK/PD) profiles in patients with external ventricular drains

OBJECTIVE

We previously investigated the pharmacokinetic and pharmacodynamic (PK/PD) parameters of routine linezolid infusions (1 h) in patients with external ventricular drains (EVD). The aim of the study was to determine whether extended linezolid infusions (200 mg/h for 3 h) were more efficacious than short linezolid infusions (600 mg/h for 1 h).

METHODS

We collected cerebrospinal fluid (CSF) and plasma samples from 10 patients who received linezolid infusions after cerebral hemorrhage surgery with EVDs. Linezolid concentrations were measured by high-performance liquid chromatography (HPLC). A Monte Carlo simulation was used to measure the probability of target attainments (PTA) and the PK/PD indexes at four minimum inhibitory concentrations (MIC).

RESULTS

When the same dose (600 mg) was given as an extended infusion (3 h), linezolid reached its maximum concentrations in the plasma and CSF at 3.00 h and 4.40 h, respectively. The mean penetration of linezolid in CSF was 41.31%. Using the parameter of AUC_{0-24 h}/MIC ≥ 100, the plasma PTA provided good coverage at > 90% when MIC was ≤ 1 μg/mL, while the values were 0 in CSF. Using the parameter %T (time) > MIC ≥ 85%, the PTA in both the plasma and CSF provided good coverage when MIC ≤ 2 μg/mL. Compared with routine infusions, prolonged infusion times (3 h) showed increased PTA of linezolid.

CONCLUSIONS

Prolonged infusion times increased the concentration of linezolid in the plasma, leading to improved therapeutic outcomes. However, this improvement did not exist in CSF. Lastly, the PK/PD indicator AUC/MIC ≥ 100 may be used to achieve improved outcomes in patients with critical infections.

Establishment of a Nomogram for Predicting Lumbar Drainage-Related Meningitis: A Simple Tool to Estimate the Infection Risk

BACKGROUND

Lumbar drainage (LD) is one of the common treatment techniques in neurosurgery. There is a risk of secondary meningitis when using this modality. We aim to predict the probability of the complication by designing a nomogram.

METHODS

A retrospective study was conducted in a teaching hospital. Data were collected and LD-related meningitis (LDRM) was identified, mainly based on clinical manifestations and cerebrospinal fluid analysis. Univariate analysis was used to screen the risk factors, and binary logistic analysis was performed to build the prediction model, which was furtherly transferred into a nomogram. The prediction performance was evaluated by receiver operating characteristic (ROC) curve, Hosmer-Lemeshow test, and nomogram calibration plot. Internal validation was processed by using ordinary bootstrapping.

RESULTS

A total of 273 patients who match the research criteria were enrolled, in which 37 cases (13.6%) were confirmed to have LDRM. Univariate analysis showed the risk factors included diabetes (p = 0.003), admission on surgical intensive care unit (p = 0.012), duration time (p < 0.001), site leakage (p < 0.001), and craniotomy (p < 0.001). In multivariate analysis, four of the variables were identified as independent risk factors to establish a prediction model, and a graphical nomogram was designed. The area under the ROC curve was 0.837, and the p value in the Hosmer-Lemeshow test was 0.610, with a mean absolute error in the calibration plot calculated as 0.022. The indices in the testing set were in good accordance with the original set when internal validation was performed.

CONCLUSIONS

This is the first study to transform the prediction model of LDRM into a nomogram, which can be considered as a tool for clinicians to assess infection risk.

The Evolution of the Role of External Ventricular Drainage in Traumatic Brain Injury

External ventricular drains (EVDs) are commonly used in neurosurgery in different conditions but frequently in the management of traumatic brain injury (TBI) to monitor and/or control intracranial pressure (ICP) by diverting cerebrospinal fluid (CSF). Their clinical effectiveness, when used as a therapeutic ICP-lowering procedure in contemporary practice, remains unclear. No consensus has been reached regarding the drainage strategy and optimal timing of insertion. We review the literature on EVDs in the setting of TBI, discussing its clinical indications, surgical technique, complications, clinical outcomes, and economic considerations.

External Ventricular Drain Management Practices in Thailand: Results of the EPRACT Study

OBJECTIVE

We explored the external ventricular drain (EVD) practices in Thailand.

METHODS

We performed a survey-based study to describe EVD insertion, maintenance, quality improvement (QI) practices, and incidence of EVD infection.

RESULTS

The study included 58 of 101 hospitals contacted (57.4% response rate), with ≥600 beds (44.8%) and dedicated neurocritical care units (53%). The reasons for EVD placement included aneurysmal subarachnoid hemorrhage, traumatic brain injury, and ventriculoperitoneal shunt malfunction or infection; 75.9% of the hospitals cared for ≤100 EVDs annually. In Thailand, nonantimicrobial EVD catheters (98.3%) were used most often. Most hospitals (56.9%) did not routinely sample the cerebrospinal fluid. Prophylactic daily antibiotic use was prevalent (62.1%). Most hospitals (77.6%) did not measure the intracranial pressure during intrahospital transport. EVD infection was a commonly (69%) tracked QI measure; however, up to one third of the hospitals did not track any EVD QI measure. Most hospitals (94.8%) had no written EVD insertion and maintenance protocols. Most hospitals (79.3%) reported an EVD infection rate of ≤5% in the previous year. The low EVD infection rate, high cost, and/or the lack of equipment could account for the low usage of antimicrobial catheters and intracranial pressure monitoring.

CONCLUSIONS

The results of the present study have identified QI opportunities in EVD management in Thailand. The development of an EVD-related QI process, reliable tracking of EVD infection rates, adaptation of U.S. guidelines to create standardized EVD protocols, and examination of the association between EVD practices and clinical outcomes in low-to middle-income countries are urgently needed.

Differential Gene Expression in Peripheral White Blood Cells with Permissive Underfeeding and Standard Feeding in Critically Ill Patients: A Descriptive Sub-study of the PermiT Randomized Controlled Trial

The effect of short-term caloric restriction on gene expression in critically ill patients has not been studied. In this sub-study of the PermiT trial (Permissive Underfeeding or Standard Enteral Feeding in Critically Ill Adults Trial- ISRCTN68144998), we examined gene expression patterns in peripheral white blood cells (buffy coat) associated with moderate caloric restriction (permissive underfeeding) in critically ill patients compared to standard feeding. Blood samples collected on study day 1 and 14 were subjected to total RNA extraction and gene expression using microarray analysis. We enrolled 50 patients, 25 in each group. Among 1751 tested genes, 332 genes in 12 pathways were found to be significantly upregulated or downregulated between study day 1 and 14 (global p value for the pathway ≤ 0.05). Using the heatmap, the differential expression of genes from day 1 to 14 in the permissive underfeeding group was compared to the standard feeding group. We further compared gene expression signal intensity in permissive underfeeding compared standard feeding by constructing univariate and multivariate linear regression models on individual patient data. We found differential expression of several genes with permissive underfeeding, most notably those related to metabolism, autophagy and other cellular functions, indicating that moderate differences in caloric intake trigger different cellular pathways.

Neuroanesthesiology Update

We provide a synopsis of innovative research, recurring themes, and novel experimental findings pertinent to the care of neurosurgical patients and critically ill patients with neurological diseases. We cover the following broad topics: general neurosurgery, spine surgery, stroke, traumatic brain injury, monitoring, and anesthetic neurotoxicity.