Freeman, William D.

The effect of induced hypertension (iHTN) on functional outcomes in noncardioembolic acute ischemic stroke (AIS) with early neurological deterioration remains unclear. We performed a systematic review and meta-analysis evaluating the safety and efficacy of iHTN vs medical management. A literature search of PubMed/MEDLINE, Web of Science, Ovid Embase, and Scopus from inception through November 6th, 2025. The protocol was registered in PROSPERO (CRD420261282211). Studies evaluating iHTN within 72 h of AIS onset and reporting 90-day functional independence (modified Rankin Scale [mRS] 0-2) were included. Safety outcome was hemorrhagic transformation. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were estimated using random-effects model based on Restricted Maximum-Likelihood (REML) methods. Three studies were included, comprising 366 patients (iHTN, n = 180; control, n = 186). Mean age was 65.8 ± 11.8 years, 60.9% were men, and the mean initial NIHSS was 5.4 ± 3.5. Target systolic blood pressure (SBP) was a 15-25% increase from baseline SBP using phenylephrine. Functional independence at 90-days occurred more often in the iHTN group than in controls (68.8% vs 50.5%; RR = 1.37; 95% CI, 1.09-1.73; P = 0.007). Hemorrhagic transformation was uncommon and did not differ significantly between groups (3.3% vs 0.5%; RR = 2.08; 95% CI, 0.05-88.07; P = 0.70). In our study, phenylephrine-induced hypertension was associated with greater 90-day functional independence in selected AIS subtypes,without a significant increase in hemorrhagic transformation. However, the limited studies, predominance of retrospective designs, exclusively Asian cohorts, and heterogeneity in treatment protocols and populations warrant cautious interpretation and underscore the need for larger multicenter RCTs.

Abstract Background/Objective: Maintaining acid-base balance within the central nervous system (CNS) is essential for neuronal homeostasis. Disruptions in this balance can result in respiratory disturbances, elevated intracranial pressure, or coma. These disturbances can occur concurrently with stroke, or CNS infection. However, they are augmented by various neurosurgical procedures involving CSF manipulation, either through direct ventricular irrigation during endoscopic neurosurgical procedures or by CSF exchange technologies. The IRRAflow active cerebrospinal fluid (CSF) exchange system (IRRA flow ) manages acid-base balance changes in the ventricular system through continuous irrigation with fluids and medications and removal of endogenous CSF. We describe a novel clinical syndrome of iatrogenic metabolic acidosis and respiratory compensation in response to exogenous fluid introduction in the ventricular fluid system using IRRAflow. The syndrome was previously seen with endoscopic neurosurgical procedures that require irrigation with normal saline. We also recommend fluid alternatives for more effective use of the IRRAflow system or different endoscopic procedure and increased awareness of CSF derangements. Methods We describe 2 cases involving patients with subarachnoid hemorrhage who developed a syndromic response characterized by tachypnea, conjunctival hyperemia, encephalopathy, and fluctuating language deficits due to continuous 0.9% normal saline irrigation. Results Both patients exhibited reproducible symptoms that persisted despite stable neuroimaging until normal saline was replaced with lactated Ringer solution, after which clinical parameters normalized within 3 hours. We named this condition SALT-CRAMD syndrome (saline acidosis leading to tachypnea, central respiratory alkalosis, and metabolic derangements). Pathophysiologic analysis based on the literature suggests that normal saline induced central hyperchloremia and dilutional acidosis, leading to heightened chemoreceptor activation in the medulla oblongata, triggering excessive respiratory drive and compensatory hypocapnia. Conclusion Awareness of SALT-CRAMD syndrome is crucial for understanding the profound pathophysiologic concepts of CSF dynamics, whether induced during treatment with active CSF exchange, endoscopic neurosurgical procedures, stroke, or CNS infections.

Abstract Introduction Intracerebral hemorrhage (ICH) carries higher morbidity and mortality than ischemic stroke. Recent studies have demonstrated improved patient outcomes by applying ultra-early bundled interventions including blood pressure management, coagulopathy reversal, and osmotic therapy. Effective strategies to deliver these ultra-early treatment options are currently being explored. On December 19th, 2022, the Mayo Clinic Comprehensive Stroke Center (CSC) launched the “ICH Phases” communication system to accelerate ICH patient care. Objective To evaluate adherence to the AHA/ASA guidelines in acute ICH care following the implementation of our novel-tiered paging system. Methods We retrospectively reviewed patients admitted with spontaneous ICH during 2024 and 2025. We excluded traumatic cases. We extracted clinical data such as time to imaging, documentation of ICH score, blood pressure control, reversal of anticoagulation, venous thrombo-embolism (VTE) prophylaxis and discharge disposition. Results Among 67 patients, 68.7% underwent CT imaging within 25 minutes. We documented the ICH score within 6 hours in 82.9% of patients. Nearly 94.7% of patients with SBP>140 mm Hg received antihypertensive therapy, yet only 18% reached target BP within 60 minutes. We completed the reversal of anticoagulation within 120 minutes in 75% of patients. VTE prophylaxis was initiated within 24 hours in 91% of patients. Discussion Our novel system demonstrated adherence to the AHA/ASA guidelines, and time sensitive benchmarks in neuroimaging, reversal of anticoagulation, and VTE prophylaxis. Early BP control remains a challenge, that highlights the discrepancy between guidelines and real-ground implementation. Conclusion A novel tiered paging system is effective for enhancing early ICH care. Such a holistic system remains critical for sustained improvement in quality of care.

Abstract Background aneurysmal subarachnoid hemorrhage (aSAH) is neurological emergency associated with substantial mortality and disability. Current grading systems such as the modified Fisher Scale (mFS) and World Federation of Neurological Societies (WFNS) score, rely on semiquantitative and examination based assessments. Hence, they demonstrate limited predictive precision. The enhanced subarachnoid hemorrhage (eSAH) score is a simplified quantitative model integrating age, Glasgow Coma Scale (GCS), and cisternal subarachnoid hemorrhage volume (SAHV) to predict clinical outcomes after aSAH. Methods We performed a retrospective multicenter cohort study that included 1088 patients across three tertiary-care centers the United States. Predictive performance for unfavorable functional outcome, in-hospital mortality and delayed cerebral ischemia (DCI) was evaluated using receiver operating characteristic (ROC) analysis and area under the curve (AUC). Comparative analyses were performed and compared to the WFNS and mFS grading systems. Results the eSAH score demonstrated excellent discrimination for unfavorable functional outcome at discharge ( AUC 0.89 ) and in-hospital mortality (AUC 0.87). The DCI subscore demonstrated good discriminatory performance for predicting DCI (AUC 0.77). Compared with conventional grading systems, this was superior to both the WFNS (AUC 0.75) and the mFS ( AUC 0.70). increasing eSAH scores were additionally associated with progressively higher rates of mortality and unfavorable functional outcomes. Conclusion the eSAH score demonstrates strong external validity, reproducibility and superior predictive performance compared with conventional grading systems in a large multicenter cohort. These findings support the clinical utility of quantitative hemorrhage burden integration for early risk stratification in patients with aSAH.

Abstract Objective Shunt-dependent hydrocephalus is a common and costly complication of aneurysmal subarachnoid hemorrhage (aSAH), affecting up to 28% of survivors. Existing prediction tools, including the Chronic Hydrocephalus Ensuing from SAH Score (CHESS), have limited discriminative accuracy. We developed the CHECKMATE score, a clinically practical tool to improve prediction of ventriculoperitoneal shunt dependency after aSAH. Methods In this multicenter retrospective cohort of 486 patients with aSAH from Mayo Clinic (January 1, 2006-December 31, 2021), we used multivariable logistic regression and machine learning to identify independent predictors of ventriculoperitoneal shunt placement. The CHECKMATE score was derived from 5 weighted variables: symptomatic hydrocephalus (10 points), intraventricular hemorrhage (5 points), SAH volume greater than 10 mL (3 points), neutrophil-to-lymphocyte ratio greater than 12 (2 points), and 10-year incremental age thresholds starting at older than 60 years (1 point each). Results Of 486 patients (mean age, 56.3 years; 64.6% female), 137 (28.2%) required ventriculoperitoneal shunt placement. The CHECKMATE score achieved an area under the curve of 0.808 (compared to 0.737 for CHESS), with a sensitivity of 0.85, specificity of 0.67, and negative predictive value of 0.92 at the optimal cutoff of 14 points. Conclusions The CHECKMATE score outperforms CHESS for predicting ventriculoperitoneal shunt dependency after aSAH and is easily used at the bedside. Its high negative predictive value helps identify low-risk patients who may benefit from earlier external ventricular drain weaning and shorter hospital stays.

Abstract Background and Objectives: Neurosurgery is a distinctive realm with a tight and strict margin of error. IRRAflow (IRRA flow ) is a US Food and Drug Administration–approved active cerebrospinal fluid exchange system that can irrigate up to 180 mL/h. The system is tightly secured, safe, and continuously monitors intracranial pressure, using a 9F dual-lumen catheter. Inserting an IRRAflow catheter is more complex than standard external ventricular drains, with a higher risk of cerebrospinal fluid leak or catheter displacement. Particularly, the extracranial component of the IRRAflow catheter insertion is prone to errors and necessitates dedicated training. We aimed to design an affordable, reusable, and easy-to-use 3-dimensional printed model that simulates the extracranial component of the IRRAflow catheter insertion. Methods: The IRRAsert simulator was designed according to recent publications. The skull was printed with polylactic acid, and the Kocher point was drilled. A mold was cast to make the scalp, and Dragon Skin FX-Pro Part A and Part B (Smooth-On, Inc) was used to create a skin flap to cover the drilled Kocher point. Results: The IRRAsert simulator replicated the external parts of the skull starting from the bone outward. It allowed measurements for designating the Kocher point, incising the skin to reveal the drilled Kocher point, tunneling under the scalp, and creating a 5-cm posterior exit incision. The endogenous property of the mixed 1:1 ratio between parts A and B allowed adhesion with the underlying skull due to the attraction between polylactic acid and silicone in a stick-and-peel fashion. This adhesion allowed for dissection of skin from the bone during tunneling for the catheter under the scalp, as well as lifting and rotating the scalp for the next user. The final cost of our simulator was $20 to print the skull permanently, with another $5 to produce the skin that can be rotated 3 times for 3 different users. Conclusion: IRRAsert is the result of multidisciplinary efforts to produce an affordable simulator for the extracranial component of IRRAflow catheter insertion.

BACKGROUND: Intraventricular hemorrhage and subarachnoid hemorrhage are associated with neuroinflammation and increased morbidity and mortality. Rapid clearance of blood from the cerebrospinal fluid space may mitigate neuroinflammatory cascades and improve clinical outcomes. This systematic review and meta-analysis aimed to compare the clinical effectiveness of active cerebrospinal fluid exchange, including neuroendoscopic lavage and IRRAflow systems, versus external ventricular drainage in patients with intraventricular hemorrhage or subarachnoid hemorrhage. METHODS: The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and thoroughly assessed databases, including PubMed, Embase, Scopus, Cochrane, and Web of Science, up to September 18, 2025. Statistical analysis, both fixed-effect and random-effect model analyses, was performed by the Comprehensive Meta-Analysis software. In addition, the Cochran Q test was conducted to determine the statistical heterogeneity. In terms of low heterogeneity, the fixed-effect model is reported. RESULTS: This review included 7 studies with a total sample size of 834. Our analysis showed that active cerebrospinal fluid exchange was associated with significantly higher hematoma clearance (odds ratio, 2.72 [95% CI, 1.22–6.08]; P =0.015), better functional outcomes (odds ratio, 1.66 [95% CI, 1.12–2.48]; P =0.012), lower shunt dependency (odds ratio, 0.22 [95% CI, 0.10–0.50]; P <0.001), and reduced infection rates (odds ratio, 0.22 [95% CI, 0.12–0.42]; P <0.001). Subgroup analysis showed that neuroendoscopic lavage was most effective for hematoma clearance, while IRRAflow reduced infection rates. Also, younger patients had better neurological recovery. CONCLUSIONS: Active cerebrospinal fluid exchange techniques demonstrated superior outcomes over external ventricular drainage in managing intraventricular hemorrhage and subarachnoid hemorrhage, particularly in clot resolution and neurological recovery. Large-scale trials are warranted.

ABSTARCT BACKGROUND: IRRAflow is a novel active cerebrospinal fluid (CSF) exchange system for the treatment of hemorrhagic strokes and intracranial infections. It is a closed system that irrigates various medications dissolved in irrigation solutions at a speed of up to 180 mL/h, expediting resolution. Disrupting this closed system to withdraw CSF samples or infuse medications is necessary in certain circumstances. We report our novel approach for maintaining the sterility of the closed IRRAflow system using a needleless extension and assess the compatibility and safety of this technology throughout treatment. METHODS: We used a needleless extension to withdraw CSF samples and deliver medications to 5 patients treated with the IRRAflow system. We used 1 stopcock with a 3-way valve, 2 neutral needleless connectors, and 2 antiseptic caps. The stopcock was connected between the irrigation and drainage ports of the catheter. The needleless connectors were mounted at the 12 o’clock position of the attached stopcock and the irrigation port with antiseptic caps covering the distal ends. To initiate fluid exchange, the 2 needleless connectors were separated. The extra stopcock valve was connected between the drainage arm, the cassette, and the irrigation arm. The needleless connectors remained mounted at the 12 o’clock position of the stopcock and irrigation port throughout treatment. RESULTS: The needleless connectors mounted on the 12 o’clock position of the stopcock and irrigation port on the drainage and irrigation arms, respectively, provided efficient management of fluid exchange, CSF fluid sampling, and medication delivery. Our needleless extension was compatible with the IRRAflow device and prevented secondary infections despite repeated CSF sampling and medication delivery. CONCLUSION: The needleless extension facilitated a simple and safe interaction with the closed IRRAflow system without compromising the sterile environment during CSF sampling and medication delivery.

Background Rapid stroke type identification is essential for time‐sensitive interventions, yet timely neuroimaging remains limited, especially in pre‐hospital and resource‐constrained settings. The EMVision emu™ Brain Scanner is a portable neurodiagnostic device using non‐ionizing electromagnetic signals to distinguish stroke subtypes. In an Australian prevalidation study enrolling 277 suspected stroke patients, it demonstrated diagnostic accuracy with sensitivity and specificity of 92% and 85% for hemorrhagic and 95% and 80% for ischemic strokes, respectively. Case studies and image reconstructions provided (figures 1 and 2). This follow‐up study aims to validate the diagnostic performance of emu™ for detecting intracranial hemorrhage in an international cohort, targeting ≥80% sensitivity and specificity. Methods A prospective, multi‐center, international, paired diagnostic accuracy study, with 4 US sites and 2 Australian sites. It will enroll 300 patients presenting within 12 hours of stroke onset. Patients will be stratified into two arms: intracranial hemorrhage, and ischemic stroke, TIA, or stroke mimic. Participants will undergo standard imaging, followed by non‐invasive scan by the emu™ device. Ground‐truth diagnoses will be adjudicated by a blinded expert panel. The primary endpoints are the sensitivity and specificity of the emu™ device for detecting hemorrhage, calculated against the reference standard. Statistical inference will rely on whether the lower bound of the 95% confidence interval for sensitivity and specificity exceeds 80%. Results First Australian and US enrollments occurred on June 11, 2025, and July 3, 2025, respectively. Latest progress in the study will be presented at the time of conference. Conclusion This is the first international validation study of a portable electromagnetic brain scanner for intracranial hemorrhage detection; a novel, non‐ionizing, diagnostic tool that can revolutionize acute stroke triage, enabling earlier treatment decisions, improved workflows, and equitable access to neuroimaging. image image

ABSTRACT Traumatic brain injury (TBI), particularly among military personnel, poses significant challenges in acute management and long-term outcomes. Difficult-to-diagnose autoregulatory and inflammatory changes lead to neurocognitive impairment, anxiety, sleep disturbance, and chronic pain. To optimize readiness and test therapeutics for both diagnostic and future TBI treatments, this feasibility study introduces a novel wearable multimodal platform that integrates photoplethysmography and infra-red (IR) sensing from a camera and a wearable sensor to detect vital signs and then leverages machine learning (ML) to predict the need for acute treatment. This prospective observational study involving 28 healthy volunteers simulated a triage emergency room workflow to test sensor accuracy and mobile app functionality. The wearable device demonstrated high accuracy in pulse rate (mean error 7.3%) and oxygen saturation (mean error −1.2%) compared to standard-of-care devices. Camera-based pulse and respiratory rate, and wearable pulse, oxygen, and temperature sensing were tested in a mock triage setting to simulate activation of light-based treatment upon detection of physiological changes of concern after acute TBI. Preliminary ML models to predict hypotension and pain based on retrospective data achieved 98.4% and 93% accuracy but showed limitations in prospective real-time applications. This study provided insights to prepare for future iterations that will integrate near-IR spectroscopy to detect cerebral oximetry, and quantum dot light-emitting diodes to activate light-based treatment (photobiomodulation) from within a wearable head dressing. The findings underscore the potential of this platform to bridge critical gaps in acute TBI care through early detection and future therapeutic intervention. Further development is needed to address environmental challenges, improve accuracy across diverse populations, and refine the device for real-time clinical use. This innovative approach has the potential to revolutionize TBI care by bridging current gaps in diagnostic and therapeutic management.