Impact of remoteness and rurality on the treatment and survival of patients with glioblastoma in the north of Scotland.

Background: The geographical catchment area served by the Neurosurgical Unit in Aberdeen, Scotland is the largest in the United Kingdom. We examined whether a distance-decay effect on survival exists for patients diagnosed with glioblastoma, who have to travel substantial distances for neurosurgical and oncological treatment in the north of Scotland. Methods: Electronic medical records of adult patients with glioblastoma, referred for treatment between 2007 and 2018, who underwent surgical resection were reviewed. Travel time by car (as a measure of distance travelled) was calculated from the patients' home to their general practice (GP) and to their main neuro-oncological centre. Results: There were 122 patients; 71 (58.2%) were male and the mean age was 57.8 years. The urban-rural split was 61.5% and 38.5%, respectively. Median driving time to the neuro-oncological centre was 36 min and to the GP this was 6 min. Most patients underwent either sub-total (49.6%) or gross total (46.3%) surgical resection. Post-operative treatments included: radiotherapy only (15.6%), chemotherapy only (6.6%), and chemotherapy with radiotherapy (63.1%). Temozolomide was used in 70.5% of patients. Seventeen patients did not receive any post-operative chemo-radiotherapy. The median survival time was 345 days. There was no statistically significant association between distance travelled and survival time in days. MGMT methylation status, extent of resection, Charlson co-morbidity index and treatment received significantly affected survival. Conclusions: There was no evidence of disadvantage on survival time for patients living further from their neuro-oncological centre compared to those who live nearer.

Theory-based implementation of an enhanced recovery protocol for cranial surgery.

OBJECTIVE: There is growing evidence for the use of enhanced recovery protocols (ERPs) in cranial surgery. As they become widespread, successful implementation of these complex interventions will become a challenge for neurosurgical teams owing to the need for multidisciplinary engagement. Here, the authors describe the novel use of an implementation framework (normalization process theory [NPT]) to promote the incorporation of a cranial surgery ERP into routine neuro-oncology practice. METHODS: A baseline audit was conducted to determine the degree of implementation of the ERP into practice. The Normalization MeAsure Development (NoMAD) questionnaire was circulated among 6 groups of stakeholders (neurosurgeons, anesthetists, intensivists, recovery nurses, preoperative assessment nurses, and neurosurgery ward staff) to examine barriers to implementation. Based on these findings, a theory-guided implementation intervention was delivered. A repeat audit and NoMAD questionnaire were conducted to assess the impact of the intervention on the uptake of the ERP. RESULTS: The baseline audit (n = 24) demonstrated limited delivery of the ERP elements. The NoMAD questionnaire (n = 32) identified 4 subconstructs of the NPT as barriers to implementation: communal specification, contextual integration, skill set workability, and relational integration. These guided an implementation intervention that included the following: 1) teamwork-focused training; 2) ERP promotion; and 3) procedure simplification. The reaudit (n = 21) demonstrated significant increases in the delivery of 5 protocol elements: scalp block (12.5% of patients before intervention vs 76.2% of patients after intervention, p < 0.00001), recommended analgesia (25.0% vs 100.0%, p < 0.00001) and antiemetics (12.5% vs 100.0%, p < 0.00001), trial without catheter (13.6% vs 88.9%, p < 0.00001), and mobilization on the 1st postoperative day (45.5% vs 94.4%, p < 0.00001). There was a significant reduction in the mean hospital length of stay from 6.3 ± 3.4 to 4.2 ± 1.7 days (p = 0.022). Two months after implementation, a repeat NoMAD survey demonstrated significant improvement in communal specification. CONCLUSIONS: Here, the authors have demonstrated the successful implementation of a cranial surgery ERP by using a systematic theory-based approach.

Cauda equina syndrome.

Aims: Patients with cauda equina syndrome (CES) require emergency imaging and surgical decompression. The severity and type of symptoms may influence the timing of imaging and surgery, and help predict the patient's prognosis. Categories of CES attempt to group patients for management and prognostication purposes. We aimed in this study to assess the inter-rater reliability of dividing patients with CES into categories to assess whether they can be reliably applied in clinical practice and in research. Methods: A literature review was undertaken to identify published descriptions of categories of CES. A total of 100 real anonymized clinical vignettes of patients diagnosed with CES from the Understanding Cauda Equina Syndrome (UCES) study were reviewed by consultant spinal surgeons, neurosurgical registrars, and medical students. All were provided with published category definitions and asked to decide whether each patient had 'suspected CES'; 'early CES'; 'incomplete CES'; or 'CES with urinary retention'. Inter-rater agreement was assessed for all categories, for all raters, and for each group of raters using Fleiss's kappa. Results: Each of the 100 participants were rated by four medical students, five neurosurgical registrars, and four consultant spinal surgeons. No groups achieved reasonable inter-rater agreement for any of the categories. CES with retention versus all other categories had the highest inter-rater agreement (kappa 0.34 (95% confidence interval 0.27 to 0.31); minimal agreement). There was no improvement in inter-rater agreement with clinical experience. Across all categories, registrars agreed with each other most often (kappa 0.41), followed by medical students (kappa 0.39). Consultant spinal surgeons had the lowest inter-rater agreement (kappa 0.17). Conclusion: Inter-rater agreement for categorizing CES is low among clinicians who regularly manage these patients. CES categories should be used with caution in clinical practice and research studies, as groups may be heterogenous and not comparable.

Comparison of External Ventricular Drains with Ventricular Access Devices for the Emergency Management of Adult Hydrocephalus.

OBJECTIVE: We compared external ventricular drains (EVDs) with percutaneous continuous cerebrospinal fluid (CSF) drainage via ventricular access devices (VADs) for the acute management of hydrocephalus in adults. METHODS: This was a retrospective review of all ventricular drains inserted for a new diagnosis of hydrocephalus into noninfected CSF over four years. We compared infection rates, return to theatre, and patient outcome between EVDs and VADs. We explored the effect of duration of drainage, frequency of sampling, hydrocephalus aetiology, and catheter location on these outcomes using multivariable logistic regression modelling. RESULTS: We included 179 drains (76 EVDs and 103 VADs). EVDs were associated with a higher rate of unplanned return to theatre for replacement or revision (27/76, 36%, vs. 4/103, 4%, OR: 13.4 95%CI: 4.3-55.8). However, infection rates were higher in VADs (13/103, 13% vs. 5/76, 7%, OR: 2.0, 95%CI: 0.65-7.7). EVDs were 91% antibiotic impregnated whereas VADs were 98% nonimpregnated. In multivariable analysis, infection was associated with duration of drainage (median: 11 days prior to infection for infected drains vs. 7 days total for noninfected drains), but not drain type (VADs vs. EVDs OR: 1.6, 95%CI: 0.5-6). CONCLUSIONS: EVDs had a higher rate of unplanned revisions but a lower infection rate compared to VADs. However, in multivariable analysis choice of drain type was not associated with infection. We suggest a prospective comparison of antibiotic impregnated VADs and EVDs using similar sampling protocols to assess whether VADs or EVDs for acute hydrocephalus have a lower overall complication rate.

A Digital Health Intervention for Concussion: Development and Clinical Feasibility Study.

BACKGROUND: Concussion is a common condition that can lead to a constellation of symptoms that affect quality of life, social integration, and return to work. There are several evidence-based behavioral and psychological interventions that have been found to improve postconcussion symptom burden. However, these are not routinely delivered, and individuals receive limited support during their concussion recovery. OBJECTIVE: This study aimed to develop and test the feasibility of a digital health intervention using a systematic evidence-, theory-, and person-based approach. METHODS: This was a mixed methodology study involving a scoping review (n=21), behavioral analysis, and logic model to inform the intervention design and content. During development, the intervention was optimized with feedback from individuals who had experienced concussions (n=12) and health care professionals (n=11). The intervention was then offered to patients presenting to the emergency department with a concussion (n=50). Participants used the intervention freely and input symptom data as part of the program. A number of outcome measures were obtained, including participant engagement with the intervention, postconcussion symptom burden, and attitudes toward the intervention. A selection of participants (n=15) took part in in-depth qualitative interviews to understand their attitudes toward the intervention and how to improve it. RESULTS: Engagement with the intervention functionality was 90% (45/50) for the symptom diary, 62% (31/50) for sleep time setting, 56% (28/50) for the alcohol tracker, 48% (24/50) for exercise day setting, 34% (17/50) for the thought diary, and 32% (16/50) for the goal setter. Metrics indicated high levels of early engagement that trailed off throughout the course of the intervention, with an average daily completion rate of the symptom diary of 28.23% (494/1750). A quarter of the study participants (13/50, 26%) were classified as high engagers who interacted with all the functionalities within the intervention. Quantitative and qualitative feedback indicated a high level of usability and positive perception of the intervention. Daily symptom diaries (n=494) demonstrated a wide variation in individual participant symptom burden but a decline in average burden over time. For participants with Rivermead scores on completion of HeadOn, there was a strong positive correlation (r=0.86; P<.001) between their average daily HeadOn symptom diary score and their end-of-program Rivermead score. Insights from the interviews were then fed back into development to optimize the intervention and facilitate engagement. CONCLUSIONS: Using this systematic approach, we developed a digital health intervention for individuals who have experienced a concussion that is designed to facilitate positive behavior change. Symptom data input as part of the intervention provided insights into postconcussion symptom burden and recovery trajectories. TRIAL REGISTRATION: ClinicalTrials.gov NCT05069948; https://clinicaltrials.gov/ct2/show/NCT05069948.

Presentation, management, and outcomes of cauda equina syndrome up to one year after surgery, using clinician and participant reporting: A multi-centre prospective cohort study.

Background: Cauda equina syndrome (CES) results from nerve root compression in the lumbosacral spine, usually due to a prolapsed intervertebral disc. Evidence for management of CES is limited by its infrequent occurrence and lack of standardised clinical definitions and outcome measures. Methods: This is a prospective multi-centre observational cohort study of adults with CES in the UK. We assessed presentation, investigation, management, and all Core Outcome Set domains up to one year post-operatively using clinician and participant reporting. Univariable and multivariable associations with the Oswestry Disability Index (ODI) and urinary outcomes were investigated. Findings: In 621 participants with CES, catheterisation for urinary retention was required pre-operatively in 31% (191/615). At discharge, only 13% (78/616) required a catheter. Median time to surgery from symptom onset was 3 days (IQR:1-8) with 32% (175/545) undergoing surgery within 48 h. Earlier surgery was associated with catheterisation (OR:2.2, 95%CI:1.5-3.3) but not with admission ODI or radiological compression. In multivariable analyses catheter requirement at discharge was associated with pre-operative catheterisation (OR:10.6, 95%CI:5.8-20.4) and one-year ODI was associated with presentation ODI (r = 0.3, 95%CI:0.2-0.4), but neither outcome was associated with time to surgery or radiological compression. Additional healthcare services were required by 65% (320/490) during one year follow up. Interpretation: Post-operative functional improvement occurred even in those presenting with urinary retention. There was no association between outcomes and time to surgery in this observational study. Significant healthcare needs remained post-operatively. Funding: DCN Endowment Fund funded study administration. Castor EDC provided database use. No other study funding was received.

Comparison of Suspected and Confirmed Internal External Ventricular Drain-Related Infections: A Prospective Multicenter United Kingdom Observational Study.

Background: Diagnosis of internal external ventricular drain (EVD)-related infections (iERI) is an area of diagnostic difficulty. Empiric treatment is often initiated on clinical suspicion. There is limited guidance around antimicrobial management of confirmed versus suspected iERI. Methods: Data on patients requiring EVD insertion were collected from 21 neurosurgical units in the United Kingdom from 2014 to 2015. Confirmed iERI was defined as clinical suspicion of infection with positive cerebrospinal fluid (CSF) culture and/or Gram stain. Cerebrospinal fluid, blood, and clinical parameters and antimicrobial management were compared between the 2 groups. Mortality and Modified Rankin Scores were compared at 30 days post-EVD insertion. Results: Internal EVD-related infection was suspected after 46 of 495 EVD insertions (9.3%), more common after an emergency insertion. Twenty-six of 46 were confirmed iERIs, mostly due to Staphylococci (16 of 26). When confirmed and suspected infections were compared, there were no differences in CSF white cell counts or glucose concentrations, nor peripheral blood white cell counts or C-reactive protein concentrations. The incidence of fever, meningism, and seizures was also similar, although altered consciousness was more common in people with confirmed iERI. Broad-spectrum antimicrobial usage was prevalent in both groups with no difference in median duration of therapy (10 days [interquartile range {IQR}, 7-24.5] for confirmed cases and 9.5 days [IQR, 5.75-14] for suspected, P = 0.3). Despite comparable baseline characteristics, suspected iERI was associated with lower mortality and better neurological outcomes. Conclusions: Suspected iERI could represent sterile inflammation or lower bacterial load leading to false-negative cultures. There is a need for improved microbiology diagnostics and biomarkers of bacterial infection to permit accurate discrimination and improve antimicrobial stewardship.

Demographics of Cauda Equina Syndrome: A Population-Based Incidence Study.

INTRODUCTION: Cauda equina syndrome (CES) has significant medical, social, and legal consequences. Understanding the number of people presenting with CES and their demographic features is essential for planning healthcare services to ensure timely and appropriate management. We aimed to establish the incidence of CES in a single country and stratify incidence by age, gender, and socioeconomic status. As no consensus clinical definition of CES exists, we compared incidence using different diagnostic criteria. METHODS: All patients presenting with radiological compression of the cauda equina due to degenerative disc disease and clinical CES requiring emergency surgical decompression during a 1-year period were identified at all centres performing emergency spinal surgery across Scotland. Initial patient identification occurred during the emergency hospital admission, and case ascertainment was checked using ICD-10 diagnostic coding. Clinical information was reviewed, and incidence rates for all demographic and clinical groups were calculated. RESULTS: We identified 149 patients with CES in 1 year from a total population of 5.4 million, giving a crude incidence of 2.7 (95% CI: 2.3-3.2) per 100,000 per year. CES occurred more commonly in females and in the 30-49 years age range, with an incidence per year of 7.2 (95% CI: 4.7-10.6) per 100,000 females age 30-39. There was no association between CES and socioeconomic status. CES requiring catheterization had an incidence of 1.1 (95% CI: 0.8-1.5) per 100,000 adults per year. The use of ICD-10 codes alone to identify cases gave much higher incidence rates, but was inaccurate, with 55% (117/211) of patients with a new ICD-10 code for CES found not to have CES on clinical notes review. CONCLUSION: CES occurred more commonly in females and in those between 30 and 49 years and had no association with socioeconomic status. The incidence of CES in Scotland is at least four times higher than previous European estimates of 0.3-0.6 per 100,000 population per year. Incidence varies with clinical diagnostic criteria. To enable comparison of rates of CES across populations, we recommend using standardized clinical and radiological criteria and standardization for population structure.

Autonomous surgical robotic systems and the liability dilemma.

Background: Advances in machine learning and robotics have allowed the development of increasingly autonomous robotic systems which are able to make decisions and learn from experience. This distribution of decision-making away from human supervision poses a legal challenge for determining liability. Methods: The iRobotSurgeon survey aimed to explore public opinion towards the issue of liability with robotic surgical systems. The survey included five hypothetical scenarios where a patient comes to harm and the respondent needs to determine who they believe is most responsible: the surgeon, the robot manufacturer, the hospital, or another party. Results: A total of 2,191 completed surveys were gathered evaluating 10,955 individual scenario responses from 78 countries spanning 6 continents. The survey demonstrated a pattern in which participants were sensitive to shifts from fully surgeon-controlled scenarios to scenarios in which robotic systems played a larger role in decision-making such that surgeons were blamed less. However, there was a limit to this shift with human surgeons still being ascribed blame in scenarios of autonomous robotic systems where humans had no role in decision-making. Importantly, there was no clear consensus among respondents where to allocate blame in the case of harm occurring from a fully autonomous system. Conclusions: The iRobotSurgeon Survey demonstrated a dilemma among respondents on who to blame when harm is caused by a fully autonomous surgical robotic system. Importantly, it also showed that the surgeon is ascribed blame even when they have had no role in decision-making which adds weight to concerns that human operators could act as "moral crumple zones" and bear the brunt of legal responsibility when a complex autonomous system causes harm.

Impact of country self citation on the ranking of the top 50 countries in clinical neurology.

OBJECTIVES: To examine the factors that influence country self-citation rate (SCR) in clinical neurology and to assess the impact of self-citation on the ranking of the top 50 countries. METHODS: SCImago Journal & Country Rank was used to collect data for the 50 most cited countries in clinical neurology during 1996-2019. Country SCR was correlated with several productivity parameters and examined statistically. Countries that dropped in their ranking after the exclusion of self-citations were identified. RESULTS: The median (range) country SCR for the 50 most cited countries was 11.3%.(5.3%- 47%). Country SCR correlated significantly with total citable documents and total cites numbers and rankings. The exclusion of self-citations led to a drop in the ranking of 8(16%) countries only. No significant difference between the total and net total cites rankings was observed. CONCLUSIONS: Self-citation can be appropriate and reflect an expansion on earlier research. Highly cited productive countries tend to have high country SCR. Excluding self-citations had minimal impact on the ranking of the top 50 countries. Our findings indicate that self-citation is unlikely to influence country standing amongst the top 50 and does not support the argument for eliminating self-citations from citation-based metrics. A more globalization through international collaboration in research is encouraged.

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

OBJECTIVE: Freehand external ventricular drain (EVD) insertion is associated with a high rate of catheter misplacement. Image-guided EVD placement with neuronavigation or ultrasound has been proposed as a safer, more accurate alternative with potential to facilitate proper placement and reduce catheter malfunction risk. This study aimed to determine the impact of image-guided EVD placement on catheter tip position and drain functionality. METHODS: This study is a secondary analysis of a data set from a prospective, multicenter study. Data were collated for EVD placements undertaken in the United Kingdom and Ireland from November 2014 to April 2015. In total, 21 large tertiary care academic medical centers were included. RESULTS: Over the study period, 632 EVDs were inserted and 65.9% had tips lying free-floating in the CSF. Only 19.6% of insertions took place under image guidance. The use of image guidance did not significantly improve the position of the catheter tip on postoperative imaging, even when stratified by ventricular size. There was also no association between navigation use and drain blockage. CONCLUSIONS: Image-guided EVD placement was not associated with an increased likelihood of achieving optimal catheter position or with a lower rate of catheter blockage. Educational efforts should aim to enhance surgeons' ability to apply the technique correctly in cases of disturbed cerebral anatomy or small ventricles to reduce procedural risks and facilitate effective catheter positioning.

The synapse in traumatic brain injury.

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide and is a risk factor for dementia later in life. Research into the pathophysiology of TBI has focused on the impact of injury on the neuron. However, recent advances have shown that TBI has a major impact on synapse structure and function through a combination of the immediate mechanical insult and the ensuing secondary injury processes, leading to synapse loss. In this review, we highlight the role of the synapse in TBI pathophysiology with a focus on the confluence of multiple secondary injury processes including excitotoxicity, inflammation and oxidative stress. The primary insult triggers a cascade of events in each of these secondary processes and we discuss the complex interplay that occurs at the synapse. We also examine how the synapse is impacted by traumatic axonal injury and the role it may play in the spread of tau after TBI. We propose that astrocytes play a crucial role by mediating both synapse loss and recovery. Finally, we highlight recent developments in the field including synapse molecular imaging, fluid biomarkers and therapeutics. In particular, we discuss advances in our understanding of synapse diversity and suggest that the new technology of synaptome mapping may prove useful in identifying synapses that are vulnerable or resistant to TBI.

Attitudes of Patients and Their Relatives Toward Artificial Intelligence in Neurosurgery.

BACKGROUND: Artificial intelligence (AI) may favorably support surgeons but can result in concern among patients and their relatives. The aim of this study was to evaluate attitudes of patients and their relatives regarding use of AI in neurosurgery. METHODS: In a 2-stage cross-sectional survey, a qualitative survey was administered to a focus group of former patients to investigate their perception of AI and its role in neurosurgery. Five themes were identified and used to generate a case-based quantitative survey administered to inpatients and their relatives over a 2-week period. Presented AI platforms were rated appropriate and acceptable using 5-point Likert scales. Demographic data were collected. χ2 test was used to determine whether demographics influenced participants' attitudes. RESULTS: In the first stage, 20 participants responded. Five themes were identified: interpretation of imaging (4/20; 20%), operative planning (5/20; 25%), real-time alert of potential complications (10/20; 50%), partially autonomous surgery (6/20; 30%), and fully autonomous surgery (3/20; 15%). In the second stage, 107 participants responded. Most thought it appropriate and acceptable to use AI for imaging interpretation (76.7%; 66.3%), operative planning (76.7%; 75.8%), real-time alert of potential complications (82.2%; 72.9%), and partially autonomous surgery (58%; 47.7%). Conversely, most did not think that fully autonomous surgery was appropriate (27.1%) or acceptable (17.7%). Demographics did not have a significant influence on perception. CONCLUSIONS: Most patients and their relatives believed that AI has a role in neurosurgery and found it acceptable. Notable exceptions were fully autonomous systems, with most wanting the neurosurgeon ultimately to remain in control.

Evaluation of nationwide referral pathways, investigation and treatment of suspected cauda equina syndrome in the United Kingdom.

Purpose: Cauda equina syndrome (CES) is a spinal emergency with clinical symptoms and signs that have low diagnostic accuracy. National guidelines in the United Kingdom (UK) state that all patients should undergo an MRI prior to referral to specialist spinal units and surgery should be performed at the earliest opportunity. We aimed to evaluate the current practice of investigating and treating suspected CES in the UK. Materials and Methods: A retrospective, multicentre observational study of the investigation and management of patients with suspected CES was conducted across the UK, including all patients referred to a spinal unit over 6 months between 1st October 2016 and 31st March 2017. Results: A total of 28 UK spinal units submitted data on 4441 referrals. Over half of referrals were made without any previous imaging (n = 2572, 57.9%). Of all referrals, 695 underwent surgical decompression (15.6%). The majority of referrals were made out-of-hours (n = 2229/3517, 63.4%). Patient location and pre-referral imaging were not associated with time intervals from symptom onset or presentation to decompression. Patients investigated outside of the spinal unit experienced longer time intervals from referral to undergoing the MRI scan. Conclusions: This is the largest known study of the investigation and management of suspected CES. We found that the majority of referrals were made without adequate investigations. Most patients were referred out-of-hours and many were transferred for an MRI without subsequently requiring surgery. Adherence to guidelines would reduce the number of referrals to spinal services by 72% and reduce the number of patient transfers by 79%.

Subarachnoid haemorrhage with negative initial neurovascular imaging: a systematic review and meta-analysis.

BACKGROUND: In patients with spontaneous subarachnoid haemorrhage (SAH), a vascular cause for the bleed is not always found on initial investigations. This study aimed to systematically evaluate the delayed investigation strategies and clinical outcomes in these cases, often described as "non-aneurysmal" SAH (naSAH). METHODS: A systematic review was performed in concordance with the PRISMA checklist. Pooled proportions of primary outcome measures were estimated using a random-effects model. RESULTS: Fifty-eight studies were included (4473 patients). The cohort was split into perimesencephalic naSAH (PnaSAH) (49.9%), non-PnaSAH (44.7%) and radiologically negative SAH identified on lumbar puncture (5.4%). The commonest initial vascular imaging modality was digital subtraction angiography. A vascular abnormality was identified during delayed investigation in 3.9% [95% CI 1.9-6.6]. There was no uniform strategy for the timing or modality of delayed investigations. The pooled proportion of a favourable modified Rankin scale outcome (0-2) at 3-6 months following diagnosis was 92.0% [95% CI 86.0-96.5]. Complications included re-bleeding (3.1% [95% CI 1.5-5.2]), hydrocephalus (16.0% [95% CI 11.2-21.4]), vasospasm (9.6% [95% CI 6.5-13.3]) and seizure (3.5% [95% CI 1.7-5.8]). Stratified by bleeding pattern, we demonstrate a higher rate of delayed diagnoses (13.6% [95% CI 7.4-21.3]), lower proportion of favourable functional outcome (87.2% [95% CI 80.1-92.9]) and higher risk of complications for non-PnaSAH patients. CONCLUSION: This study highlights the heterogeneity in delayed investigations and outcomes for patients with naSAH, which may be influenced by the initial pattern of bleeding. Further multi-centre prospective studies are required to clarify optimal tailored management strategies for this heterogeneous group of patients.

Understanding cauda equina syndrome: protocol for a UK multicentre prospective observational cohort study.

INTRODUCTION: Cauda equina syndrome (CES) is a potentially devastating condition caused by compression of the cauda equina nerve roots. This can result in bowel, bladder and sexual dysfunction plus lower limb weakness, numbness and pain. CES occurs infrequently, but has serious potential morbidity and medicolegal consequences. This study aims to identify and describe the presentation and management of patients with CES in the UK. METHODS AND ANALYSIS: Understanding Cauda Equina Syndrome (UCES) is a prospective and collaborative multicentre cohort study of adult patients with confirmed CES managed at specialist spinal centres in the UK. Participants will be identified using neurosurgical and orthopaedic trainee networks to screen referrals to spinal centres. Details of presentation, investigations, management and service usage will be recorded. Both patient-reported and clinician-reported outcome measures will be assessed for 1 year after surgery. This will establish the incidence of CES, current investigation and management practices, and adherence to national standards of care. Outcomes will be stratified by clinical presentation and patient management. Accurate and up to date information about the presentation, management and outcome of patients with CES will inform standards of service design and delivery for this important but infrequent condition. ETHICS AND DISSEMINATION: UCES received a favourable ethical opinion from the South East Scotland Research Ethics Committee 02 (Reference: 18/SS/0047; IRAS ID: 233515). All spinal centres managing patients with CES in the UK will be encouraged to participate in UCES. Study results will be published in medical journals and shared with local participating sites. TRIAL REGISTRATION NUMBER: ISRCTN16828522; Pre-results.

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

OBJECTIVES: External ventricular drain (EVD) insertion is a common neurosurgical procedure. EVD-related infection (ERI) is a major complication that can lead to morbidity and mortality. In this study, we aimed to establish a national ERI rate in the UK and Ireland and determine key factors influencing the infection risk. METHODS: A prospective multicentre cohort study of EVD insertions in 21 neurosurgical units was performed over 6 months. The primary outcome measure was 30-day ERI. A Cox regression model was used for multivariate analysis to calculate HR. RESULTS: A total of 495 EVD catheters were inserted into 452 patients with EVDs remaining in situ for 4700 days (median 8 days; IQR 4-13). Of the catheters inserted, 188 (38%) were antibiotic-impregnated, 161 (32.5%) were plain and 146 (29.5%) were silver-bearing. A total of 46 ERIs occurred giving an infection risk of 9.3%. Cox regression analysis demonstrated that factors independently associated with increased infection risk included duration of EVD placement for ≥8 days (HR=2.47 (1.12-5.45); p=0.03), regular sampling (daily sampling (HR=4.73 (1.28-17.42), p=0.02) and alternate day sampling (HR=5.28 (2.25-12.38); p<0.01). There was no association between catheter type or tunnelling distance and ERI. CONCLUSIONS: In the UK and Ireland, the ERI rate was 9.3% during the study period. The study demonstrated that EVDs left in situ for ≥8 days and those sampled more frequently were associated with a higher risk of infection. Importantly, the study showed no significant difference in ERI risk between different catheter types.