The research team, led by Annika Meyer of University Hospital Cologne together with colleagues from several German institutions, conducted the review in accordance with PRISMA 2020 guidelines and registered the protocol prospectively before data collection began. In January and February 2026, the investigators searched PubMed, Web of Science, Dimensions AI, The Lens, and the Cochrane Library, supplemented by screening of Google Scholar records and, notably, by artificial intelligence-assisted literature discovery tools including ChatGPT 5.2, OpenEvidence, and SciSpace, which were used in a supplementary role to catch studies that conventional database queries might have missed. The search yielded 778 records, from which ten studies encompassing 177 neurocritical care patients in Europe and China ultimately met the inclusion criteria. Eight of those studies, covering 120 patients, provided extractable data for the meta-analysis of the primary outcome: the change in intracranial pressure from a supine baseline to the prone position.

The pooled results showed a statistically significant but modest rise in intracranial pressure of 5.06 millimeters of mercury when patients were turned prone, with a 95 percent confidence interval spanning 2.05 to 8.06 millimeters of mercury. Between-study heterogeneity was substantial, with an I-squared statistic of 76.7 percent, reflecting the wide variety of protocols, patient populations, and positioning techniques across the included studies. In descriptive terms, pooled mean intracranial pressure increased from 11.10 millimeters of mercury at baseline to 16.13 millimeters of mercury during proning. Crucially, both values remained below the treatment thresholds commonly used to define intracranial hypertension, which typically begin around 20 to 22 millimeters of mercury. The increase, in other words, was real but generally did not push patients into the danger zone.

Perhaps the most clinically important finding concerned what happened after patients were turned back. In five studies with 45 patients, the pooled change in intracranial pressure between the supine baseline and the period after returning to supine was minus 0.41 millimeters of mercury, with a confidence interval of minus 2.34 to 1.51, meaning there was no meaningful difference from pre-proning values. The pressure elevation during proning was therefore transient and fully reversible, a position-dependent effect rather than a sustained deterioration of intracranial dynamics. Cerebral perfusion pressure, the gradient that actually drives blood flow to brain tissue, showed no significant change either during proning or afterward, with mean differences close to zero and wide confidence intervals. Only one included study reported vasopressor adjustments, and no changes in vasopressor requirements were observed during the prone phase.

Against this modest hemodynamic cost, the respiratory benefits were consistent and striking. Every one of the ten studies that reported systemic oxygenation parameters, whether the partial pressure of arterial oxygen alone or the PaO2-to-FiO2 ratio, documented improvement during prone positioning. Four studies went further and measured invasive brain tissue oxygenation directly, using parenchymal sensors, and found that brain tissue oxygen levels also rose while patients were prone. This detail carries particular weight because, in three of the four studies, baseline brain tissue oxygenation values fell within ranges previously associated with cerebral ischemia and unfavorable neurological outcomes. In one study, brain tissue oxygenation improved during proning even as cerebral perfusion pressure declined slightly, suggesting that better oxygenation of arterial blood can translate into better oxygen delivery to tissue even when perfusion pressure shifts modestly.

The physiological mechanism behind the transient pressure rise is well understood from decades of neurosurgical anesthesia practice. Prone positioning increases intrathoracic and intraabdominal pressures, which can impede cerebral venous outflow, and suboptimal head and neck alignment can compromise jugular venous drainage. Because the skull is a rigid compartment governed by the Monro-Kellie doctrine, any increase in venous blood volume must be offset by displacement of cerebrospinal fluid or arterial blood, and patients with limited intracranial compliance have less reserve to absorb the change. Consistent with this framework, several included studies found that tolerance of proning was usually apparent within the first hour and was associated with lower baseline intracranial pressure. One study observed larger pressure increases in patients without external ventricular drainage, underscoring the role of cerebrospinal fluid diversion in preserving intracranial reserve.

The clinical relevance of a five-millimeter-of-mercury rise is therefore highly patient dependent. In individuals with preserved compensatory reserve, the transient elevation can be buffered by normal autoregulatory displacement of fluid compartments. In patients already hovering near the threshold of intracranial hypertension, however, the same increase may exhaust the remaining reserve and trigger an exponential rise in pressure. This helps explain why, across six studies that reported it, roughly 8.89 percent of patients had prone positioning prematurely discontinued because of intracranial pressure elevation, with a confidence interval of 4.21 to 17.78 percent. The authors suggest a pragmatic interpretation: rather than treating proning as a binary yes-or-no decision, clinicians should implement it as a monitored therapeutic trial with an explicit early reassessment point, typically within the first hour, when vulnerability is most likely to declare itself.

The evidence base behind these conclusions comes with important caveats that the authors address candidly. Only two of the ten studies were randomized trials, and one of those was judged to have a high risk of bias due to problems with the randomization process and missing outcome data, while the other raised some concerns. The eight nonrandomized studies carried an overall moderate risk of bias, driven primarily by serious confounding and selective reporting. Using the GRADE framework, the overall certainty of evidence was rated very low. Notably, patients with intracranial pressure monitoring have been excluded from roughly 75 percent of prior trials evaluating prone positioning for acute respiratory distress syndrome, which is precisely why this population has remained so poorly characterized. Additional limitations include inconsistent control of arterial carbon dioxide levels, a major determinant of cerebral blood flow, and the fact that brain tissue oxygenation reflects only regional rather than global oxygen delivery.

The heterogeneity across studies also extended to technique, and the authors argue that positioning details are far from trivial technicalities. Whether patients were placed fully prone or semi-prone, whether the head was elevated or horizontal, and whether the head was kept neutral or rotated are likely to be major determinants of intracranial tolerance. Turning maneuvers themselves can provoke coughing, ventilator desynchrony, and sympathetic activation, all of which acutely raise intracranial pressure, while concomitant spinal injuries, which are relatively common in traumatic brain injury, can complicate mobilization. Excessive sedation stabilizes physiology but delays neurological assessment, a tradeoff that cannot be eliminated but can be managed through protocolized practice.

The bottom line for clinicians is a cautious green light. The findings support considering prone positioning in selected neurocritical care patients with moderate-to-severe hypoxemic respiratory failure when invasive intracranial pressure monitoring is in place and timely de-escalation pathways are available, in line with European Society of Intensive Care Medicine consensus recommendations that already endorse proning when intracranial pressure is not elevated. Because hypoxemia is a major driver of secondary brain injury, and pulmonary complications affect an estimated 5 to 30 percent of acute brain injury patients while worsening outcomes and prolonging intensive care stays, the stakes of leaving respiratory failure untreated are considerable. The authors emphasize that current evidence supports a cautious approach but not definitive thresholds or protocols, and they call for larger prospective studies using standardized proning protocols, time-resolved intracranial pressure data, stratification by baseline intracranial reserve, and patient-centered neurological outcomes. Until such trials arrive, the message from this analysis is that the feared catastrophe of proning the injured brain is, in most monitored patients, a manageable and reversible bump rather than a cliff edge.

Subject of Research: Effects of prone positioning on intracranial pressure and oxygenation in neurocritical care patients with invasive intracranial pressure monitoring

Article Title: Prone Positioning in Neurocritical Care Patients with Invasive Intracranial Pressure Monitoring: A Systematic Review and Meta-analysis

Article References: Meyer, A., Overbeek, R., Mühlhausen, L., Küchler, J., Ditz, C., Foit, A., Hof, M., Goldbrunner, R., & Steinbicker, A. U. (2026). Prone Positioning in Neurocritical Care Patients with Invasive Intracranial Pressure Monitoring: A Systematic Review and Meta-analysis. Neurocritical Care. https://doi.org/10.1007/s12028-026-02667-0

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02667-0

Keywords: prone positioning, intracranial pressure, neurocritical care, acute brain injury, ARDS, cerebral perfusion pressure, brain tissue oxygenation, systematic review, meta-analysis, traumatic brain injury, subarachnoid hemorrhage, intensive care medicine

Traumatic brain injury, or TBI, is a disruption in normal brain function caused by a forceful bump, blow, jolt or penetrating object to the head. The mechanisms are disturbingly ordinary: motor vehicle collisions, assaults, gunshot wounds and falls, with falls posing a particular risk among older adults. What follows the initial injury is often a long and disorienting recovery that extends far beyond the hospital walls. Survivors may face lasting changes in cognition, mood and behavior, and the people who absorb most of those changes day to day are frequently spouses, parents, adult children and siblings who receive little formal preparation for the role they are about to assume.

Kreitzer’s interest in this population grew directly out of her clinical work. She completed a neurocritical care fellowship at UC and is a member of the UC Stroke Team, and she has spent substantial time in the neuro intensive care unit treating patients with severe brain injuries. From my experience in the neuro ICU, I’ve developed a deep interest in working with patients who have suffered traumatic brain injuries and with their family members, who often become their caregivers, she said. That bedside perspective shaped her research trajectory, pushing her to think about the recovery period as a family-wide event rather than a purely patient-centered one.

The intervention at the heart of the new trial, CG-Well, short for CareGiver Well, was developed on the basis of earlier studies and delivers structured wellness content through web modules and phone coaching. The program includes 43 modules, available online and in print, tailored to address families’ unmet needs during recovery. The topics focus on common issues likely to arise for families in the first six months after a TBI, including coping with stress, navigating the Family and Medical Leave Act, transitioning from the ICU to a rehabilitation facility or long-term acute care, and preparing the home for a loved one’s return, Kreitzer explained. In other words, the curriculum targets the practical and emotional chokepoints that caregivers reliably encounter, from employment protections to the logistics of moving a medically fragile relative between care settings.

The new grant builds on Kreitzer’s earlier project, CG-Well 1, which enrolled 100 family caregivers and was funded by a five-year NIH K23 career development award. That pilot produced encouraging signals. It was a positive trial, Kreitzer said. Caregivers enrolled in CG-Well reported greater satisfaction and fewer symptoms of psychological stress than those who received the control intervention. Caregivers in this population face high rates of anxiety, depression and burnout, and the pilot results suggested that a structured, remotely delivered program could meaningfully move the needle on those outcomes without requiring families to travel to a clinic they may have neither the time nor the transportation to reach.

CG-Well 2 is designed to test the intervention with far greater rigor and at a scale that speaks to real-world implementation. The trial will evaluate the program as a scalable offering, beginning within the first two weeks after a patient’s injury and continuing through the transition from hospital to home. That timing is deliberate. The first six months after a TBI can be especially intense for caregivers, who may experience changes in a loved one’s behavior while managing caregiving demands and making decisions about treatment and rehabilitation. The trial will also examine effects on caregiver health and well-being, as well as caregiving appraisal, the term researchers use for how a caregiver perceives their situation, along with patient outcomes and the intervention’s feasibility, acceptability and cost.

The study design follows the classic randomized controlled trial architecture that regulators and health systems look for before adopting a program widely. Participants will be randomly assigned to one of two groups. One group will receive regular phone calls from a trained interventionist with a social work or nursing background who will check in and guide caregivers through the tailored modules. The comparison group will not receive the modules; those caregivers will have access only to publicly available information, and their phone calls will involve active listening but no tailored intervention or advice. This active-control structure is important because it separates the specific effect of the CG-Well content from the general benefit of simply having someone attentive on the phone, a distinction that has tripped up many psychosocial intervention studies in the past.

To reach a sample capable of detecting reliable effects, the trial will enroll up to 354 patient-caregiver pairs across four U.S. sites: the University of Cincinnati, Ohio State University in Columbus, Washington University in St. Louis and the University of Washington in Seattle. Enrollment is expected to begin in early 2027. Kreitzer’s co-investigators at UC include Stephanie Fink, lead coordinator and clinical research project manager in the Department of Emergency Medicine; Heidi Sucharew, PhD, research professor in the Department of Emergency Medicine; Brad Kurowski, MD, professor-affiliate in the Department of Pediatrics and Cincinnati Children’s Division of Rehabilitation Medicine; Shari Wade, PhD, professor-affiliate in the Department of Pediatrics and director of research at Cincinnati Children’s Division of Rehabilitation Medicine; and Tamilyn Bakas, PhD, professor and endowed chair in the College of Nursing. The spread of expertise, spanning emergency medicine, biostatistics, pediatric rehabilitation medicine and nursing science, reflects the reality that caregiver support cuts across nearly every specialty involved in brain injury care.

The stakes extend well beyond the families enrolled in the study. Informal family caregivers provide billions of dollars’ worth of unpaid care in the United States each year, and when they burn out, the consequences cascade: patients are readmitted to hospitals, placed in institutional care earlier than necessary, or left without consistent supervision during a recovery window when structured support matters most. An intervention that is web-based and telephone-delivered is inherently scalable, which is precisely why the trial is measuring cost and acceptability alongside clinical outcomes. If CG-Well 2 confirms the pilot findings, hospitals and rehabilitation systems could have a low-cost, evidence-based template for supporting caregivers nationally, delivered through channels that already exist in nearly every American household.

For Kreitzer, the R01 represents a major career milestone, the transition from mentored career development funding to independent investigator status at the NIH. But the milestone is also a signal of where the field is heading. Neurocritical care has traditionally measured success in survival and discharge disposition, while the long shadow cast by moderate-to-severe TBI on families went largely unmeasured. A rigorously designed, multisite trial that treats caregiver psychological health as a primary target, and that begins support within two weeks of injury rather than after a crisis, reflects a growing recognition that the unit of recovery after brain injury is not the patient alone but the household around them. Whether CG-Well 2 can convert a promising pilot into a scalable standard of care will become clear as enrollment opens in early 2027 and results accumulate over the five-year award period.

Subject of Research: A randomized clinical trial of a web- and telephone-based wellness intervention for family caregivers of traumatic brain injury patients

Article Title: University of Cincinnati physician-researcher earns $2.5 million NIH grant for caregiver wellness trial

Article References: University of Cincinnati physician-researcher earns $2.5 million NIH grant for caregiver wellness trial. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: traumatic brain injury, family caregivers, NIH R01 grant, CG-Well, randomized clinical trial, University of Cincinnati, caregiver burnout, neurocritical care, psychological distress, emergency medicine, rehabilitation, telehealth intervention

The original study, published in August 2026, was an exploratory translational proteomics investigation. Rather than examining blood, the researchers turned to cerebrospinal fluid, the clear liquid that bathes the brain and spinal cord and that often reflects biochemical events happening inside the skull far more faithfully than peripheral blood does. Using proteomic analysis, they identified hemopexin as a molecule of interest, reporting that its levels in cerebrospinal fluid appeared to track with the later development of secondary sepsis and with in-hospital outcomes in patients who had suffered a spontaneous intracerebral hemorrhage, a devastating form of stroke caused by a ruptured blood vessel inside the brain.

Hemopexin is not an arbitrary candidate. It is the body’s highest-affinity binder of free heme, the iron-containing molecule at the heart of hemoglobin. When blood cells rupture, as they do in large quantities after an intracerebral hemorrhage, heme is released into surrounding tissues and fluids. Free heme is a double-edged molecule: it is essential for life, but in its unbound form it catalyzes the formation of reactive oxygen species, damages cell membranes, and amplifies inflammation. Hemopexin acts as a molecular sponge, sequestering heme and escorting it to receptors that clear it from the extracellular space. In the brain, where hemorrhage floods tissue with hemoglobin breakdown products, hemopexin sits at the front line of the body’s attempt to contain the damage.

That biology is precisely why the protein has attracted attention before. A 2018 study published in the Journal of Cerebral Blood Flow and Metabolism by Leclerc and colleagues reported that increased brain hemopexin levels improved outcomes after intracerebral hemorrhage in experimental models, supporting the idea that the protein is protective rather than merely a passive marker of bleeding. Against that backdrop, the new proteomic finding that cerebrospinal fluid hemopexin might signal something as seemingly distant as sepsis, a systemic infection-driven syndrome, was provocative. It suggested that the biochemical storm unleashed by brain injury and the immune collapse of sepsis might be connected through measurable molecular threads.

The letter to the editor, authored by Ahmed H and Niazi M and entitled Cerebrospinal Fluid Hemopexin as a Sepsis-Specific Signal After Intracerebral Hemorrhage, challenged that interpretation. Letters of this kind are a standard mechanism of scientific self-correction: they allow outside experts to interrogate a study’s assumptions, methods, and conclusions in public. The correspondents appear to have questioned whether the hemopexin signal truly represents a sepsis-specific phenomenon, or whether it might instead reflect more general processes, such as the sheer volume of bleeding, blood-brain barrier disruption, or the intensity of the inflammatory response to the hemorrhage itself. That distinction matters enormously, because a biomarker that merely tracks injury severity would be far less useful for clinical decision-making than one that specifically predicts a treatable complication like infection.

In their formal response, published on October 6, 2026, Xie and colleagues defended their work while engaging with the critique. The response, prepared by the same team from the Department of Critical Care Medicine at Huashan Hospital, addressed the methodological concerns raised by the correspondents. Among the references cited in the exchange is a landmark methodological paper by Riley and colleagues in the British Medical Journal on calculating the sample size required for developing a clinical prediction model, a detail that signals the debate touched on the statistical foundations of biomarker research. Prediction models, unlike simple association studies, are intended to generate risk estimates for individual patients, and the field has learned through painful experience that models built on small samples with too many variables tend to fail when tested on new patients.

That concern is especially acute in sepsis research after intracerebral hemorrhage. Patients with brain bleeds are among the most vulnerable in the intensive care unit: they may be immobile, intubated, unable to protect their airways, and fitted with invasive devices, all of which raise infection risk. Detecting sepsis early in such patients is notoriously difficult because the classic signs, fever, elevated heart rate, abnormal white blood cell counts, can be produced by the brain injury itself. A 2025 multicenter retrospective study published in the Journal of Medical Internet Research by Liu and colleagues attempted to build an explainable prediction model for sepsis in patients with intracerebral hemorrhage, underscoring both the clinical demand for such tools and the methodological rigor required to build them credibly. Against this landscape, any proposed biomarker, particularly one drawn from an invasive fluid like cerebrospinal fluid, must clear a high evidentiary bar.

The Shanghai team’s response also reflects the realities of exploratory translational science. The original study was explicitly framed as exploratory, a word that carries weight in the biomarker literature. Exploratory proteomics studies generate hypotheses; they do not, on their own, establish clinical validity. The researchers acknowledged the preliminary nature of their findings while maintaining that hemopexin deserves continued investigation as a candidate marker. Their response, like the original study, was published without dedicated funding, and the authors declared no conflicts of interest. They also disclosed that ChatGPT was used solely for English language editing, with all authors reviewing and verifying the final content, a level of transparency about artificial intelligence use that has become increasingly expected in biomedical publishing.

What makes this exchange worth watching is what it reveals about the path from a proteomic discovery to a bedside test. For cerebrospinal fluid hemopexin to become a genuine clinical tool, several hurdles remain. The finding would need independent replication in larger, ideally multicenter cohorts. Researchers would need to demonstrate that hemopexin adds predictive value beyond existing clinical variables such as hemorrhage volume, location, Glasgow Coma Scale score, and standard inflammatory markers. They would need to establish whether serial measurements, rather than a single time point, improve prediction. And because lumbar puncture is invasive and not without risk in patients with mass lesions in the brain, the practical case for a cerebrospinal fluid marker would need to be compelling, or the signal would need to be mirrored in blood.

The deeper scientific question raised by the letter, whether hemopexin is a sepsis-specific signal or a general readout of injury and inflammation, is exactly the kind of question that rigorous debate is designed to resolve. If hemopexin turns out to be a broad marker of heme burden and barrier disruption, it may still be valuable, perhaps as an indicator of secondary brain injury. If it is genuinely specific to the transition toward systemic infection, it could open a window into the poorly understood mechanisms by which catastrophic brain injury destabilizes systemic immunity. Either answer would advance the field; the current exchange ensures the question is asked properly. For now, the verdict of the scientific process is still pending, and patients with intracerebral hemorrhage, who face sepsis as one of the most dangerous complications of their condition, await the larger studies that will determine whether this heme-scavenging protein can deliver on its early promise.

Subject of Research: Cerebrospinal fluid hemopexin as a candidate biomarker for secondary sepsis after spontaneous intracerebral hemorrhage

Article Title: Response to the Letter to the Editor Entitled “Cerebrospinal Fluid Hemopexin as a Sepsis-Specific Signal After Intracerebral Hemorrhage” Regarding the Study “Cerebrospinal Fluid Hemopexin as a Candidate Biomarker for Secondary Sepsis and In-hospital Outcome After Spontaneous Intracerebral Hemorrhage: An Exploratory Translational Proteomics Study”

Article References: Xie, T., Feng, W., He, Y., Cao, Y., & Deng, S. (2026). Response to the Letter to the Editor Entitled “Cerebrospinal Fluid Hemopexin as a Sepsis-Specific Signal After Intracerebral Hemorrhage” Regarding the Study “Cerebrospinal Fluid Hemopexin as a Candidate Biomarker for Secondary Sepsis and In-hospital Outcome After Spontaneous Intracerebral Hemorrhage: An Exploratory Translational Proteomics Study”. Neurocritical Care. https://doi.org/10.1007/s12028-026-02663-4

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02663-4

Keywords: hemopexin, cerebrospinal fluid, sepsis, intracerebral hemorrhage, biomarkers, proteomics, neurocritical care, heme, prediction models, inflammation, stroke, critical care

The clinical paradox the researchers set out to address is well known to intensive care physicians. In patients with structural brain injury, gas exchange and airway protection can become dissociated: the lungs and respiratory muscles may be perfectly capable of sustaining breathing, yet the neurological machinery guarding the airway lags behind. Conventional practice bridges this gap with low-level pressure support ventilation, in which the machine delivers small bursts of positive pressure with each breath. But that perceived safety may be deceptive. By offloading the inspiratory muscles, even modest pressure support can over-assist, suppressing the patient’s own respiratory drive and, over time, contributing to ventilator-induced diaphragmatic dysfunction—a condition that can transform a stable patient into one who is genuinely difficult to wean.

High-flow tracheal oxygen, or HFTO, offers a fundamentally different approach. Instead of cyclic pressure assistance, it delivers a continuous stream of warmed, humidified gas at high flow rates through the endotracheal tube. This mitigates the inspiratory resistance the tube itself imposes and provides a modest positive end-expiratory pressure effect, while leaving the work of breathing entirely to the patient. Evidence in tracheostomized patients has been emerging, but high-resolution physiological data in intubated patients had been scarce. The Beijing team, led by Yi-Min Zhou and Guang-Qiang Chen, designed a prospective randomized pilot study to fill that void, registering the trial on ClinicalTrials.gov and obtaining institutional ethics approval and informed consent from all participants or their legal representatives.

Between December 2025 and February 2026, the researchers screened thirty intubated patients within twenty-four hours of elective brain tumor resection. Twenty-four met the strict enrollment criteria: neurological stability with no intracranial hypertension for at least a day, a Glasgow Coma Scale score of at least nine, a successful thirty-minute spontaneous breathing trial on minimal support, and documented impairment of airway protection—assessed with a validated scoring tool—that was expected to persist for at least forty-eight hours. Patients with obesity, chronic obstructive pulmonary disease, asthma, or advanced heart failure were excluded. One patient was withdrawn after intracranial rebleeding, leaving twenty-three for analysis: twelve assigned to HFTO and eleven to low-level pressure support.

The study’s technical sophistication is what sets it apart. Rather than relying on clinical impressions, the team inserted esophageal manometry catheters, verified with the Baydur occlusion test, to measure the esophageal pressure–time product per minute—a gold-standard index of the work the inspiratory muscles perform with every breath. They also calculated the pressure generated by the inspiratory muscles and performed serial diaphragmatic ultrasound at baseline and at two, twelve, twenty-four, and forty-eight hours, tracking diaphragmatic thickness at end-expiration, the thickening fraction, and excursion during tidal breathing. Arterial blood gases, airway pressures, and hemodynamics were sampled at every time point, giving an unusually complete physiological portrait of what happens when positive pressure is withdrawn.

The primary finding was a striking divergence in the temporal trajectory of inspiratory effort. At baseline, the two groups were statistically indistinguishable. But repeated-measures analysis of variance revealed a significant group-by-time interaction, driven almost entirely by an abrupt physiological step-up in the HFTO group immediately after positive pressure support was withdrawn. Crucially, that elevated effort did not continue to climb; it stabilized at a safe plateau from two hours onward through the full forty-eight-hour observation window. The work of breathing did not progressively worsen or accumulate over time, which the authors note aligns with physiological expectations in patients with healthy lungs. The pattern for inspiratory muscle pressure mirrored the same trajectory.

Perhaps the most reassuring result concerned the diaphragm. Despite the higher workload, none of the ultrasound-derived indices—thickness, thickening fraction, or excursion—showed significant changes in either group, and no participant in either arm experienced a reduction in diaphragmatic thickness of twenty percent or more relative to baseline. This dissociation between increased global inspiratory effort and preserved diaphragmatic structure suggests that the loading imposed by HFTO remained within the adaptive capacity of the respiratory muscles over the short term. It also hints that HFTO may occupy a physiological sweet spot: enough activation to keep the muscle engaged, not so much as to cause injury.

Safety signals were largely favorable, with important nuances. Airway pressures in the HFTO group fell to near-zero or slightly negative values, in sharp contrast to the stable positive pressures in the ventilation group, and this difference was highly significant throughout. As expected with the loss of positive end-expiratory pressure, the ratio of arterial oxygen to inspired oxygen fraction declined modestly and carbon dioxide levels rose slightly in the HFTO group. Yet these changes did not translate into clinical failure: the rate of respiratory deterioration requiring escalation was statistically similar between groups, at twenty-five percent with HFTO versus 18.2 percent with pressure support. A minority of HFTO patients did exhibit episodes of inspiratory effort exceeding the predefined safety threshold, a reminder that removing both pressure assistance and end-expiratory pressure can unmask latent respiratory load in some individuals, and that the strategy demands careful monitoring rather than passive assumption of safety.

The clinical endpoints, though underpowered, offered an intriguing signal. Patients treated with HFTO accumulated a median of twenty-seven ventilator-free days at day twenty-eight, compared with twenty-one days in the pressure support group, a univariate difference the authors attribute primarily to earlier discontinuation of mechanical ventilation rather than earlier removal of the artificial airway itself. Artificial airway-free days and intensive care unit length of stay were comparable. Extubation success within seventy-two hours of study completion was similarly high in both arms, and reintubation and tracheostomy rates did not differ. No cases of inadequate humidification were reported, and no serious adverse events were attributable to the interventions.

The authors are careful to frame these findings as hypothesis-generating rather than practice-changing. The study was a single-center pilot with a small sample, an open-label design, and a narrowly defined population of relatively preserved brain tumor patients; the results cannot be extrapolated to severe traumatic brain injury, intracranial hemorrhage, or patients with obesity and lung disease. The design also cannot disentangle whether the observed effects stem from withdrawing cyclic pressure assistance, losing positive end-expiratory pressure, or both. Still, the conceptual contribution is substantial: liberation from the ventilator and removal of the artificial airway may be two distinct, separable steps in neurosurgical care. By acting as a kind of physiological stress test, high-flow tracheal oxygen could spare rapidly recovering patients unnecessary tracheostomies while identifying those with persistent deficits who truly need early surgical airways. Larger multicenter trials will now be needed to determine whether this elegant decoupling of ventilation from airway management delivers tangible benefits across the broader neurocritical population.

Subject of Research: Physiological comparison of high-flow tracheal oxygen and pressure support ventilation in neurosurgical patients with delayed extubation after brain tumor surgery

Article Title: Physiological Effects of High-Flow Tracheal Oxygen vs. Pressure Support Ventilation in Neurosurgical Patients with Brain Tumors Facing Delayed Extubation: A Pilot Study

Article References: Zhou, Y.-M., Ma, Y.-J., Tian, Y., Zhou, J.-F., Shi, G.-Z., Zhou, J.-X., & Chen, G.-Q. (2026). Physiological Effects of High-Flow Tracheal Oxygen vs. Pressure Support Ventilation in Neurosurgical Patients with Brain Tumors Facing Delayed Extubation: A Pilot Study. Neurocritical Care. https://doi.org/10.1007/s12028-026-02656-3

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02656-3

Keywords: high-flow tracheal oxygen, pressure support ventilation, mechanical ventilation weaning, delayed extubation, neurocritical care, brain tumor surgery, diaphragmatic function, inspiratory effort, esophageal manometry, ventilator-induced diaphragmatic dysfunction, airway protection, pilot study

The core of the argument is deceptively simple. A platelet count tells you how many platelets are circulating, but says nothing about whether they work. Platelets contribute to hemostasis through adhesion, activation, granule release, aggregation, and support of thrombin generation, and none of these functions is captured by a routine count. Multiple studies have now documented profound platelet dysfunction in patients with traumatic brain injury even when their counts sit comfortably within the normal range. The authors define this dysfunction as a measurable impairment in agonist-induced aggregation, in the responsiveness of specific receptor pathways, or in the platelet’s contribution to whole-blood clot strength, occurring disproportionately to or entirely in the absence of thrombocytopenia. In other words, a patient can have plenty of platelets and still have platelets that fail.

The biological explanation lies in the unique nature of brain injury. When neural tissue is disrupted, it releases tissue factor, damage-associated molecular patterns, microparticles, and lipid mediators into the circulation, triggering thrombin generation, platelet activation, and ultimately receptor desensitization. The result is a paradoxical hemostatic state the authors describe as activation exhaustion: early procoagulant activation coexists with downstream hyporesponsiveness. Platelet activation and platelet dysfunction, far from being mutually exclusive, appear to be overlapping temporal phases of the same post-injury response. This may explain a frustrating clinical pattern in which patients with traumatic brain injury suffer early hemorrhagic progression of their intracranial lesions and later develop thrombotic complications, two seemingly opposite outcomes arising from the same underlying biology.

The strongest mechanistic evidence comes from a study by Castellino and colleagues, who examined 70 patients with isolated head injury, carefully excluding hemorrhagic shock, hypotension, and antiplatelet medication use. In severe traumatic brain injury, they found adenosine diphosphate, or ADP, pathway inhibition of 93.1 percent, with an interquartile range of 44.8 to 98.3 percent, compared with just 15.5 percent in controls, a difference that was highly statistically significant, and the arachidonic acid pathway was involved concurrently. A parallel rat model confirmed ADP inhibition of 77.6 percent, plus or minus 6.7 percent, just 15 minutes after injury. These findings establish that brain injury alone, independent of systemic hemodynamic compromise, generates profound receptor-level platelet dysfunction, a mechanism distinct from pharmacological blockade and from inhibition driven by circulating mediators.

Current clinical guidelines recommend maintaining platelet counts above 50 billion per liter in active intracranial hemorrhage and above 100 billion per liter around surgery. Those thresholds remain essential, the authors stress, but they address only quantity. A patient whose count is well above both limits may still harbor significant dysfunction at the level of the ADP/P2Y12 or arachidonic acid/cyclooxygenase-1 receptor pathways. The authors also warn against two opposite errors: equating thrombocytopenia with platelet failure, and treating any detected dysfunction as an automatic indication for transfusion. Their framework rests on three clinical questions: which phenotype is present, is it clinically meaningful, and can correcting it actually improve outcomes?

Detecting these phenotypes requires functional testing, and here the landscape is complicated. Standard coagulation tests, including prothrombin time, international normalized ratio, and fibrinogen measurement, are essentially blind to platelet function. Viscoelastic assays such as thromboelastography and rotational thromboelastometry assess whole-blood clot kinetics and strength, and platelet mapping modules add agonist-specific response data. Other platforms, including Multiplate, VerifyNow, and light transmission aggregometry, measure different biological parameters and cannot be directly compared with one another. Cross-platform equivalence in traumatic brain injury has not been established, and the most frequently cited working thresholds, ADP or arachidonic acid inhibition greater than 60 percent on thromboelastography with platelet mapping, were never prospectively validated. They represent observational approximations, not clinical standards, and no universally accepted intervention cutoffs exist for any platform.

The therapeutic evidence is strikingly discordant, and the authors argue that the discordance follows a pattern rather than being random. On the positive side, one retrospective series found that goal-directed platelet transfusion guided by platelet mapping in severe traumatic brain injury was associated with lower mortality, and a platelet mapping algorithm reduced transfusion exposure without apparent harm in patients exposed to antiplatelet drugs. Against this, multiple studies found no benefit and potential harm from empirical platelet transfusion or desmopressin in less severely injured populations or when treatment was not guided by functional testing. The positive studies were conducted in severe injury with documented profound dysfunction and function-guided decisions; the negative studies applied empirical treatment in milder populations. The lesson, the authors conclude, is that intervention should be phenotype-guided and risk-stratified, not routine and empirical.

The risks of getting this wrong are not trivial. Platelet transfusion carries the danger of transfusion-associated circulatory overload, transfusion-related acute lung injury, alloimmunization, and prothrombotic complications, while desmopressin, typically dosed at 0.3 to 0.4 micrograms per kilogram intravenously in structured protocols, can cause hyponatremia, fluid retention, and thrombosis. The authors frame their recommendation through the lens of patient blood management: the question is not whether platelets are good or bad, but whether a clinically relevant, modifiable phenotype exists in which intervention is likely to change meaningful outcomes. They propose a five-category taxonomy matching platelet-related phenotypes to clinical context, dominant mechanism, and therapeutic implication, while candidly noting that this construct is expert-synthesized and has not been prospectively validated as a diagnostic classification system.

The practical approach they sketch is deliberately cautious. Platelet function testing is most defensible in moderate-to-severe injury, traumatic intracranial hemorrhage, radiological progression, planned neurosurgery or invasive neuromonitoring, known preinjury antiplatelet exposure, systemic polytrauma with coagulopathy, or unexplained bleeding despite a normal count. When function is preserved, empirical reversal should generally be avoided. When dysfunction is documented in high-risk patients requiring surgery or invasive monitoring, desmopressin or platelet transfusion may be considered according to phenotype, antiplatelet exposure, count, and procedural urgency, with post-intervention reassessment by clinical status, imaging, and repeat functional testing. Centers without access to viscoelastic platforms can fall back on clinical risk stratification using the Glasgow Coma Scale, lesion subtype, antiplatelet exposure, and procedural urgency, consistent with American College of Surgeons guidance. In emergent surgical scenarios, urgency simply overrides testing; in nonemergent settings, a 30-to-60-minute window permits targeted hemostatic preparation.

The authors are explicit about the limits of their case. Most clinical evidence is observational, retrospective, or single-center; interassay discordance remains a fundamental barrier; dysfunction rarely occurs in isolation and overlaps with fibrinogen abnormalities, acidosis, hypothermia, hypocalcemia, and hemodilution; the dynamic evolution of dysfunction over the first 72 hours is poorly characterized; and findings from moderate-to-severe cohorts cannot be extrapolated to mild injury. Many studies report laboratory correction without demonstrating improved patient outcomes. What they call for is a new generation of prospective, multicenter trials to determine which assay best identifies clinically meaningful dysfunction, which threshold predicts hemorrhagic progression, and whether phenotype-guided correction improves neurological outcomes rather than merely normalizing laboratory values. In neurocritical care, they write, what is hidden beyond the platelet count may be clinically decisive, and the next step is not simply to transfuse more platelets but to understand which platelet phenotype matters, when it matters, and how it can be safely corrected.

Subject of Research: Platelet dysfunction as a hemostatic phenotype in traumatic brain injury coagulopathy

Article Title: Rethinking Platelet Dysfunction in Traumatic Brain Injury: From Platelet Count to Hemostatic Phenotype

Article References: Quintana Diaz, M., & Godoy, D. A. (2026). Rethinking Platelet Dysfunction in Traumatic Brain Injury: From Platelet Count to Hemostatic Phenotype. Neurocritical Care. https://doi.org/10.1007/s12028-026-02670-5

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02670-5

Keywords: traumatic brain injury, platelet dysfunction, coagulopathy, hemostatic phenotype, thromboelastography, platelet mapping, platelet transfusion, desmopressin, intracranial hemorrhage, neurocritical care, patient blood management, P2Y12 pathway

The original investigation, published in the journal Neurocritical Care by Xie and colleagues, set out to answer a deceptively simple question: can the protein composition of the fluid bathing the brain reveal which patients with intracerebral hemorrhage will go on to develop secondary sepsis during their hospital stay? Using an exploratory proteomics approach, the researchers examined cerebrospinal fluid samples and identified hemopexin as a candidate biomarker, one whose levels appeared to track both the emergence of sepsis and the overall in-hospital outcome. If the finding holds up in larger and more diverse cohorts, it could give clinicians a biochemical head start on a complication that is far easier to treat when caught early.

To understand why hemopexin makes biological sense as a player in this drama, it helps to know what the protein actually does. Hemopexin is a plasma glycoprotein produced mainly by the liver, and it binds free heme — the iron-containing prosthetic group of hemoglobin — with the highest affinity of any known protein. After an intracerebral hemorrhage, red blood cells that escape into brain tissue lyse and release hemoglobin and heme in large quantities. Free heme is not an innocent bystander; it is a potent pro-oxidant and pro-inflammatory molecule that catalyzes the formation of reactive oxygen species, damages the blood-brain barrier, and amplifies the very inflammatory cascades that can spiral into systemic illness. Hemopexin mops up this heme and shuttles it to the liver for degradation, acting as a critical line of defense against heme-driven toxicity.

Earlier experimental work had already hinted that hemopexin sits at the fulcrum of recovery after brain bleeds. A 2018 study published in the Journal of Cerebral Blood Flow and Metabolism reported that increased brain hemopexin levels improved outcomes after intracerebral hemorrhage in animal models, supporting the idea that the heme-scavenging system is not merely a passive witness to injury but an active participant in the brain’s response. Against that backdrop, the new finding that cerebrospinal fluid hemopexin might also serve as a sepsis-specific signal adds an intriguing systemic dimension: the same protein that protects the injured brain locally may also register, or even mediate, the body-wide inflammatory storm that accompanies sepsis.

The clinical stakes are considerable. Spontaneous intracerebral hemorrhage accounts for a substantial share of stroke worldwide and carries high mortality and disability rates, which is why the American Heart Association and American Stroke Association issued updated management guidelines in 2022 covering everything from blood pressure control to surgical intervention. Within this framework, post-hemorrhagic sepsis remains a stubborn problem: it prolongs intensive care stays, worsens functional outcomes, and complicates decisions about the withdrawal or escalation of care. Current detection relies on nonspecific markers such as fever, white blood cell counts, and inflammatory indices like procalcitonin and C-reactive protein, none of which are specific to the neurocritical population. A cerebrospinal fluid biomarker that rises ahead of overt sepsis could, in principle, reshape surveillance on the neuro-ICU.

Yet the path from an exploratory proteomics signal to a clinically trusted biomarker is littered with statistical pitfalls, and this is precisely where the new letter to the editor enters the story. Humaiz Ahmed and Mahroo Niazi of Karachi Medical and Dental College published a correspondence in Neurocritical Care engaging directly with the original study, and their critique centers on the statistical architecture of the biomarker analysis rather than on the underlying biology. Their concerns are grounded in two classic methodological references that have shaped how clinical prediction research is judged for decades.

The first is the influential 1996 simulation study by Peduzzi and colleagues on the number of events per variable in logistic regression analysis. That work established a widely cited rule of thumb: logistic regression models need roughly ten outcome events for every predictor variable to produce stable, unbiased estimates. When the number of events is small relative to the number of candidate predictors — a situation that arises almost inevitably in exploratory proteomics, where hundreds or thousands of proteins are screened in modest patient cohorts — the resulting models are prone to overfitting, inflated effect sizes, and poor performance when applied to new patients. Ahmed and Niazi invoke this principle to question whether the hemopexin-sepsis association, however biologically plausible, can be reliably estimated from the sample at hand.

The second pillar of their critique draws on the 2020 guidance by Riley and colleagues, published in the BMJ, on calculating the sample size required for developing a clinical prediction model. That framework argues that prediction model studies should be designed with a target sample size determined in advance, based on the number of candidate predictors, the expected outcome proportion, and the desired precision of key parameters — not simply on whatever cohort happens to be available. Applied to the hemopexin study, the implication is that an exploratory translational analysis, however carefully conducted, may not have been powered to deliver a prediction model that clinicians can trust at the bedside. The letter thus functions less as a demolition of the finding and more as a call for the rigorous, pre-specified validation work that biomarker science demands.

The debate also unfolds against a rapidly evolving backdrop of sepsis prediction in intracerebral hemorrhage. In 2025, a multicenter retrospective study published in the Journal of Medical Internet Research identified and validated an explainable prediction model for sepsis in patients with intracerebral hemorrhage, demonstrating growing interest in machine-learning and clinically interpretable tools for this exact problem. In such a competitive field, any new biomarker — whether a single protein like hemopexin or a composite score — will be judged not only on its biological story but on whether it adds predictive value beyond existing clinical variables, and whether it survives external validation in independent, multicenter cohorts. The correspondence from Ahmed and Niazi is, in effect, a reminder that the bar for that evidence is high and well defined.

What emerges from this exchange is a picture of science working as intended. The original proteomics study offers a biologically coherent candidate: a heme-scavenging protein whose cerebrospinal fluid levels could plausibly reflect both the severity of intracranial injury and the systemic inflammatory state that predisposes to sepsis. The letter to the editor subjects that candidate to the statistical scrutiny that separates promising signals from clinical tools, citing the events-per-variable literature and prediction model sample size guidance as the relevant standards. The study authors have published a response, keeping the dialogue open. For patients and clinicians, the takeaway is one of cautious optimism: hemopexin may yet earn a place in the neurocritical care toolkit, but it will have to pass through larger, prospectively designed validation studies before a cerebrospinal fluid measurement becomes a routine part of sepsis surveillance after brain hemorrhage. Until then, the molecule that ferries heme out of the injured brain remains one of the most interesting leads in a field where every early warning counts.

Subject of Research: Cerebrospinal fluid hemopexin as a candidate biomarker for secondary sepsis and in-hospital outcome after spontaneous intracerebral hemorrhage

Article Title: Cerebrospinal Fluid Hemopexin as a Sepsis-Specific Signal After Intracerebral Hemorrhage

Article References: Ahmed, H., & Niazi, M. (2026). Cerebrospinal Fluid Hemopexin as a Sepsis-Specific Signal After Intracerebral Hemorrhage. Neurocritical Care. https://doi.org/10.1007/s12028-026-02664-3

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02664-3

Keywords: hemopexin, cerebrospinal fluid, intracerebral hemorrhage, sepsis, biomarkers, proteomics, neurocritical care, logistic regression, prediction models, heme scavenging, stroke, in-hospital outcome

The answer, distilled from three decades of clinical research, is more nuanced than the simple dictum that time equals damage. The reviewers found that longer seizure duration was more consistently and more independently associated with worse functional outcome, meaning lasting motor or cognitive impairment, than with mortality itself. The link between duration and death, while present in many individual studies, proved weaker and less reliable once other determinants were taken into account. The reason, the authors argue, is that mortality in status epilepticus is shaped by a crowded field of competing forces: the underlying cause of the seizure, the patient’s premorbid vulnerability, and the severity of systemic complications such as hypoxia, hyperthermia, and metabolic derangement. Duration, in other words, is only one voice in a chorus.

To appreciate why this finding matters, it helps to understand what happens to the brain during prolonged seizure activity. Experimental work dating back to the classic 1973 studies by Meldrum and colleagues in paralyzed, artificially ventilated baboons demonstrated that even when systemic factors are controlled, prolonged seizures injure neurons. Later human autopsy studies, including work by Fujikawa and colleagues published in 2000, documented neuronal loss in patients who died of status epilepticus without systemic complications. Excitotoxic mechanisms, in which excessive glutamate signaling floods neurons with calcium, combined with GABAergic receptor internalization that makes seizures progressively resistant to standard antiseizure drugs, create a vicious cycle in which the seizure itself remodels the circuits that should terminate it. This pharmacoresistance is precisely why early treatment matters: benzodiazepines work far better in the first minutes than after an hour of continuous firing.

Yet the new review exposes a methodological Achilles heel that has haunted this literature since its inception. The definition and measurement of seizure duration varied enormously across the forty-three included studies. Some counted duration from the onset of clinically visible convulsions; others anchored it to electrographic onset on continuous EEG. Some measured the time to seizure termination under treatment; others summed cumulative seizure time across recurrences. Analytical strategies diverged just as widely, with some studies treating duration as a continuous variable and others dichotomizing patients at thresholds that ranged from thirty minutes to several hours, often without explicit justification. The reviewers assessed risk of bias with the QUIPS tool and synthesized the outcome-specific associations narratively, precisely because the heterogeneity made a formal meta-analysis of pooled effect estimates untenable.

The mortality signal illustrates the problem vividly. Thirty-one of the included studies examined death as an outcome, spanning settings from population-based cohorts in Richmond, Virginia and Auckland, New Zealand to intensive care units across Europe and tertiary centers in Asia. Landmark work such as the 1994 study by Towne and colleagues on determinants of mortality, and more recent analyses of long-term survival trajectories using the ACD score, consistently identified etiology, age, and level of consciousness as dominant predictors. Against those heavyweight variables, duration often lost statistical independence. A brief seizure caused by a massive stroke can be lethal, while a prolonged but eventually controlled seizure in a young patient with a reversible metabolic trigger may leave no lasting deficit. Duration, the review concludes, should be read as a context-dependent prognostic marker rather than an absolute threshold.

Functional outcome told a different and arguably more coherent story. Twenty-six studies assessed motor or cognitive impairment after status epilepticus, and here longer duration aligned more reliably with worse results. Studies of prolonged and super-refractory status epilepticus, including cohorts from Basel and Erlangen and the French multicenter experience reported by Legriel and colleagues, found that patients whose seizures persisted for hours or days faced substantially higher risks of dependency and cognitive decline. Cognitive studies using formal neuropsychometric instruments, such as the analysis by Adachi and colleagues with the Wechsler Adult Intelligence Scale-Revised, documented measurable intellectual deterioration after prolonged episodes. The biological plausibility is strong: the longer networks remain in an ictal state, the more extensive the excitotoxic injury to hippocampal and neocortical structures that subserve memory and motor control.

Refractoriness, the tendency of a seizure to resist first- and second-line therapy, added a third dimension. Only seven studies examined this outcome, so the evidence base is thin, but the reviewers describe it as limited yet consistent: prolonged seizures were linked to treatment resistance. This relationship is bidirectional in practice, because delayed treatment extends duration and extended duration breeds pharmacoresistance through receptor trafficking. A 2021 study by Gutiérrez-Viedma and colleagues showed that therapy delay in status epilepticus extends its duration and worsens prognosis, while work by Guterman and colleagues demonstrated that the pattern of treatment progression itself shapes the burden of illness. Recent analyses, including a 2026 study suggesting that treatment adequacy outweighs treatment sequence in nonconvulsive status epilepticus, reinforce the message that what clinicians do, and how quickly, matters as much as the clock alone.

The review also grapples with the thorny question of where a seizure begins and ends, a problem that a companion 2026 scoping review by Khan and colleagues tackled directly by proposing a framework for standardizing the endpoint of status epilepticus. In convulsive seizures, onset is usually timed from the first observable motor manifestation, but in nonconvulsive status epilepticus, which can occur without any visible convulsion, onset may only be revealed by EEG, sometimes hours after the true start. Recurrence rules differ too: is a seizure that stops and restarts within an hour one prolonged event or two separate ones? Each choice changes the measured duration and can flip a patient across a categorical threshold. The reviewers call for standardized onset and termination criteria, explicit recurrence rules, and harmonized statistical modeling so that future studies can be compared and combined meaningfully.

For clinicians at the bedside, the practical takeaways remain reassuringly aligned with long-standing practice. Time is still brain, and the pharmacological window for terminating a seizure with benzodiazepines closes quickly. But the review cautions against reading duration as a standalone death sentence or a rigid cutoff for aggressive escalation. A patient’s trajectory is jointly determined by the electroclinical phenotype of the seizure, whether convulsive, focal, nonconvulsive, or the devastating post-anoxic variety, by the underlying etiology, whether acute structural injury, infection, autoimmune encephalitis, or drug withdrawal, and by systemic severity. Prognostic scores that integrate these domains, rather than duration alone, offer the most honest guidance for counseling families and calibrating intensive care.

For researchers, the message is a call to methodological discipline. The Pisa team’s synthesis, conducted under PRISMA 2020 reporting standards and published as Volume 273, article 644 of the Journal of Neurology, does not deliver a single magic number, and it deliberately refuses to invent one. Instead, it maps the terrain: duration matters most for functional recovery, less decisively for survival, and plausibly for refractoriness, but only when measured and modeled consistently. As continuous EEG monitoring spreads and machine-learning approaches to seizure detection mature, the raw material for precise duration measurement is finally becoming available at scale. The challenge now, the authors argue, is to agree on the rules of the game, so that the next systematic review can move beyond narrative synthesis and tell clinicians exactly how many minutes separate a good outcome from a devastating one.

Subject of Research: Association between duration of status epilepticus and mortality, functional outcome, and treatment refractoriness in adults

Article Title: Associations between duration of status epilepticus and clinical outcomes in adults: a systematic review

Article References: Iannaccone, F., Scarpitta, C., De Rossi, E., Milano, C., Turco, F., Bonanni, E., Fornai, F., Ceravolo, R., & Pizzanelli, C. (2026). Associations between duration of status epilepticus and clinical outcomes in adults: a systematic review. Journal of Neurology, 273(10), Article 644. https://doi.org/10.1007/s00415-026-14179-0

Image Credits: AI Generated

DOI: 10.1007/s00415-026-14179-0

Keywords: status epilepticus, seizure duration, mortality, functional outcome, refractory status epilepticus, prognosis, systematic review, neurology, epilepsy, electroencephalography, neurocritical care, excitotoxicity

The review, led by Táya Figueiredo de Oliveira Fiore and colleagues, prospectively registered in PROSPERO and conducted under the PRISMA 2020 and SWiM reporting frameworks, synthesized 20 reports encompassing 11,096 participant records with confirmed aSAH. The studies, published between 2015 and 2026, spanned Asia, Europe, South America, North America and Oceania, and compared clinical outcomes across different onset-to-treatment windows ranging from less than six hours to fifteen days or more. Eighteen of the studies were retrospective cohorts and two were post hoc analyses of randomized trial data — but crucially, in none of them was treatment timing actually randomized, making every comparison observational by nature.

The team’s central question was deceptively simple: does the interval between aneurysm rupture and definitive repair — whether by microsurgical clipping or endovascular coiling — independently determine mortality, functional recovery, and complications such as rebleeding, vasospasm, delayed cerebral ischemia, hydrocephalus, and length of hospital stay? To answer it, the reviewers weighted propensity-adjusted and comprehensively adjusted multivariable analyses far more heavily than crude or descriptive comparisons, and graded the certainty of evidence using the GRADE framework. For the timing-mortality association, certainty was downgraded to very low — the lowest possible category — because of serious risk of bias, inconsistency, and imprecision.

One finding stood out with relative clarity: earlier aneurysm securement genuinely reduces pretreatment rebleeding, the catastrophic rerupture that can occur while the aneurysm remains unsecured. Studies that included untreated or markedly delayed patients showed dramatic gradients. In one cohort, rebleeding occurred in seven percent of patients treated within 24 hours, ten percent treated at 24 to 72 hours, and 38 percent treated after 72 hours — with 16 percent of untreated patients also bleeding. Another study reported rebleeding in zero percent of patients clipped within six hours versus 49.1 percent of those never repaired. These comparisons align with classic data showing that ultra-early treatment within six hours cuts rebleeding risk dramatically, and they underpin the 2023 American Heart Association/American Stroke Association Class 1 recommendation to treat as early as feasible, ideally within 24 hours of onset.

Beyond rebleeding, however, the evidence became murky. Across 19 studies reporting functional outcome, eight favored earlier treatment, four favored later treatment, four found no independent association after adjustment, and three showed non-significant trends. The most methodologically robust analyses — those adjusting for baseline clinical severity measured on the WFNS and Hunt-Hess scales — were predominantly null. Significant adjusted associations favoring early repair tended to arise in studies plagued by treated-survivor selection, incomplete confounder control, or composite exposure definitions. Mortality data were similarly discordant: two analyses favored earlier treatment, three favored later treatment, and four found no difference at all.

The most provocative results came from the only two studies that modeled onset-to-treatment time as a continuous variable rather than forcing patients into arbitrary cutoffs like under or over 24 hours. Using flexible cubic spline models, one large multicenter analysis of 3,560 patients identified a statistically significant U-shaped relationship between treatment time and mortality, with the estimated risk lowest at approximately 32.6 hours. The other study found a similar but non-significant pattern with a nadir near 12.2 hours. These nonlinear curves may help reconcile the seemingly contradictory findings of decades of dichotomous timing studies — but the reviewers are emphatic that they are hypothesis-generating only, not a validated therapeutic window.

Why would a mid-range interval appear optimal? The answer lies in two insidious statistical traps. The first is confounding by indication: the sickest patients, those with the worst WFNS and Hunt-Hess grades, are treated most urgently, making early treatment appear spuriously harmful in unadjusted comparisons. The second is survivor bias: a patient can only appear in a delayed-treatment group if they survive long enough to reach it, making later treatment appear spuriously beneficial. Neither bias can be fully corrected in retrospective analyses, no matter how sophisticated the propensity matching. Strikingly, in one trial analysis, the apparent excess risk of ultra-early treatment attenuated almost entirely once patients who rebled early were reclassified or excluded.

The review also examined whether the choice of repair technique modifies the timing effect. Of three studies that formally tested a modality-timing interaction, only one — the same large continuous-time analysis — found a significant interaction for mortality, with the U-shaped curve more pronounced in the microsurgical group and more gradual in the endovascular group. The other two found nothing, and stratified analyses showed no consistent modality-specific pattern. Direct clipping-versus-coiling comparisons across the included studies were heterogeneous and outcome-specific, with no consistent independent advantage for either technique after adjustment, echoing the broader randomized evidence that favors coiling in suitable patients but shows convergence in risk-adjusted contemporary cohorts.

For the secondary outcomes, the timing signal essentially vanished. Neither continuous-time analysis found any association between treatment time and delayed cerebral ischemia or postoperative cerebral ischemia. Hydrocephalus showed no reproducible link, with one unadjusted finding of more shunt-dependent hydrocephalus after early treatment likely reflecting the simple fact that sicker patients get treated sooner. Length of stay was underexplored and discordant. Isolated subgroup findings — such as higher infarction risk with treatment beyond 24 hours in moderate-grade patients, or increased procedural risk when operating during the vasospasm phase — were not reproduced across overall populations.

The reviewers conclude that current guidelines remain firmly supported: aneurysms should be secured as early as feasible, and nothing in the evidence justifies intentional delay or a specific alternative timing target. But they also issue a clear call to arms for the field. Future research must model treatment time as a continuous exposure using restricted cubic splines, rigorously adjust for clinical severity and age, stratify by modality with formal interaction testing, and — critically — include patients who die before treatment, whose absence from nearly every existing cohort distorts the entire evidence base. The review also cautions that its findings, generated predominantly in high-volume centers in Asia and Europe, may not translate to settings where patients arrive days after onset; cohorts in middle-income countries have reported median ictus-to-treatment intervals of four to nine days. Until prospective multicenter registries with standardized definitions deliver cleaner data, the race against the clock continues — guided by the one outcome where speed undeniably matters: stopping the aneurysm before it bleeds again.

Subject of Research: The association between onset-to-treatment time and clinical outcomes after aneurysmal subarachnoid hemorrhage

Article Title: Timing of aneurysm repair and clinical outcomes after aneurysmal subarachnoid hemorrhage: a systematic review

Article References: Fiore, T. F. D. O., Vieira, Â. M. A., Magalhães, F. D. F., de Souza, C. G., Alves Filho, C. A. F., & Barboza, T. (2026). Timing of aneurysm repair and clinical outcomes after aneurysmal subarachnoid hemorrhage: a systematic review. Journal of Neurology, 273(10), Article 582. https://doi.org/10.1007/s00415-026-14063-x

Image Credits: AI Generated

DOI: 10.1007/s00415-026-14063-x

Keywords: aneurysmal subarachnoid hemorrhage, aneurysm repair timing, rebleeding, microsurgical clipping, endovascular coiling, mortality, functional outcome, confounding by indication, survivor bias, delayed cerebral ischemia, systematic review, neurocritical care

The study, led by Alexis Carriere and Stephane Legriel of the Centre Hospitalier de Versailles together with a broad network of French intensivists, set out to answer a deceptively simple question: does fever developing within the first 24 hours after the onset of convulsive status epilepticus independently worsen neurological recovery? To find out, the researchers turned to the ICTAL Registry, a prospective, multicenter observational database that has become one of the richest sources of real-world evidence on this devastating neurological emergency. Their analysis encompassed 952 adults admitted to 23 French intensive care units, making it one of the largest efforts to date to disentangle the prognostic meaning of hyperthermia in this population.

The technical definition matters here. Fever was defined as a core temperature of at least 38 degrees Celsius, measured during the first 24 hours following seizure onset. The outcome of interest was equally concrete: a favorable neurological outcome at 90 days, operationalized as a score of 4 or 5 on the Glasgow Outcome Scale, which ranges from death and persistent vegetative states at the bottom to good recovery and moderate disability with independence at the top. This 90-day functional endpoint is widely regarded as the gold standard in neurocritical care trials because it captures what actually matters to patients and families—whether a person can think, move, and live independently after a catastrophic brain event.

What the team found was striking in its prevalence. Of the 952 patients, 382—41.2 percent—developed fever within the first 24 hours of their intensive care stay. That figure alone underscores how common this physiological disturbance is in the immediate aftermath of prolonged convulsive seizures. But the origins of that fever proved to be decidedly multifactorial. Some patients had infectious causes directly related to the status epilepticus itself, including systemic infections or infections of the central nervous system such as encephalitis or meningitis. Others developed early aspiration pneumonia, a well-known complication when consciousness is lost and airway protective reflexes fail. And a third contributor emerged that is less obvious to outsiders: the sheer intensity of the convulsive activity, which generates massive heat and triggers inflammatory cascades throughout the body.

To isolate which of these factors truly drove fever, the investigators employed sophisticated statistical machinery, including multivariable logistic regression and matching techniques designed to balance the fever and non-fever groups on measurable characteristics. After matching, a revealing pattern emerged: only the intensity of convulsive activity remained associated with the occurrence of fever. In other words, the harder and longer the brain seized, the more likely the body was to run hot. The infectious contributors, while clinically important in their own right, did not stand out as independent drivers of early fever once the analysis accounted for other variables—a finding that reframes early hyperthermia in status epilepticus as a signal of seizure severity rather than a standalone disease process.

The prognostic verdict, however, was the study’s headline result. In multivariable analyses adjusting for the full panel of potential confounders, early fever was not independently associated with 90-day functional outcome. Instead, the familiar determinants of recovery reasserted themselves. Patients younger than 60 years and those with a Charlson Comorbidity Index below 3—indicating a lighter burden of chronic illness—had significantly better odds of favorable neurological outcome. Conversely, two factors predicted poor recovery: when the underlying cause of the status epilepticus was a cerebral insult, such as a stroke or other structural brain injury, and when the episode proved refractory, meaning seizures persisted despite adequate doses of first- and second-line anticonvulsant drugs. These predictors align with decades of literature on status epilepticus outcomes, reinforcing that etiology, age, comorbidity, and treatment resistance remain the pillars of prognosis.

The biological backdrop to this question is worth unpacking. In many acute brain injuries, fever is genuinely harmful: elevated brain temperature accelerates excitotoxic neurotransmitter release, worsens metabolic supply-demand mismatch, promotes blood-brain barrier breakdown, and amplifies inflammatory signaling. Consensus guidelines for intracerebral hemorrhage, subarachnoid hemorrhage, and ischemic stroke accordingly recommend aggressive temperature control. Experimental work in epilepsy has also shown that inflammatory mediators such as cytokines can lower seizure thresholds and perpetuate epileptic activity, creating a plausible loop in which fever and seizures feed each other. It was precisely this mechanistic plausibility that made the ICTAL findings surprising—and important. If fever in status epilepticus were an independent toxin, one would expect it to survive statistical adjustment. It did not.

The authors are careful, appropriately, not to overclaim. Their conclusions note that early fever is highly prevalent and appears to reflect seizure intensity rather than overall disease severity, that it showed no independent association with 90-day neurological outcome, and that no major prognostic impact is suggested—although they explicitly acknowledge that a modest association cannot be excluded. This caution is scientifically warranted. An observational registry, however large and well-adjusted, cannot fully eliminate confounding by indication: patients who seize violently enough to become febrile are also patients whose illness is intrinsically more severe, and no statistical model can perfectly separate the heat from the fire. The researchers also stress that their findings do not permit conclusions about whether actively cooling patients—targeted temperature management—would help or harm in status epilepticus. That question was tested in a previous randomized trial by the same group, published in the New England Journal of Medicine in 2016, which found that induced hypothermia did not improve outcomes in convulsive status epilepticus, and the current results neither revive nor bury the idea of temperature intervention.

For clinicians at the bedside, the practical message is nuanced but actionable. A fever in the first day of status epilepticus should still trigger a diligent hunt for its cause—blood cultures, chest imaging, lumbar puncture when infection of the central nervous system is suspected—because treatable infections matter regardless of whether the fever itself is prognostically neutral. Aspiration pneumonia, in particular, demands vigilance and early antibiotic therapy. But the new evidence suggests that the number on the thermometer, in isolation, should not be read as a sentence on the patient’s future. The stronger prognostic signals remain the ones clinicians already know: the patient’s age, their chronic health burden, the cause of the seizures, and whether the seizures yield to treatment.

For the field of neurocritical care, the study exemplifies the value of large, prospective, disease-specific registries. The ICTAL Registry, registered with ClinicalTrials.gov and coordinated through the IctalGroup Research Network based at Versailles, has previously yielded insights ranging from early electrocardiographic changes in status epilepticus to health-related quality of life in survivors. By demonstrating that one of the most feared secondary brain insults may be a marker rather than a mechanism of poor outcome in this specific condition, the current analysis sharpens the research agenda: future work should focus on modulating seizure intensity itself and on rigorously testing temperature-control strategies in properly designed trials, rather than assuming that fever behaves identically across all forms of acute brain injury. In medicine, as this study elegantly shows, even the most intuitive assumptions deserve to be tested against data.

Subject of Research: The prognostic significance of early fever in adult convulsive status epilepticus

Article Title: Prognostic Significance of Early Fever in Convulsive Status Epilepticus: Insights from the ICTAL Registry

Article References: Carriere, A., Chelly, J., Quenot, J.-P., Lascarrou, J.-B., Bernard, C., Lesieur, O., Monchi, M., Beuret, P., Sigaud, F., Sboui, G., Bailly, P., Chambon, R., Fontaine, C., Mongardon, N., Cerf, C., Bruel, C., Pichon, N., Argaud, L., Desmeulles, I., … Legriel, S. (2026). Prognostic Significance of Early Fever in Convulsive Status Epilepticus: Insights from the ICTAL Registry. Neurocritical Care. https://doi.org/10.1007/s12028-026-02673-2

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02673-2

Keywords: status epilepticus, fever, hyperthermia, ICTAL Registry, neurocritical care, intensive care, prognosis, seizures, secondary brain injury, Glasgow Outcome Scale, temperature management, epilepsy

Traumatic brain injury remains one of the leading causes of death and long-term disability worldwide, and for patients whose injuries require surgical intervention, such as evacuation of an intracranial hematoma, the prognosis is often grim. Neurosurgeons can relieve pressure on the brain and remove life-threatening collections of blood, but the secondary injury cascade that follows the initial trauma, involving inflammation, swelling, oxidative stress, and progressive damage to the blood-brain barrier, continues to unfold in the hours and days after the operation. Decades of clinical trials have failed to produce a pharmacological therapy that reliably improves outcomes after severe brain trauma, leaving supportive and surgical care as the mainstays of treatment. Against that backdrop, any signal that an existing, widely prescribed drug class might improve survival is bound to attract intense attention.

GLP-1 receptor agonists, which include drugs such as liraglutide and semaglutide, mimic the action of the gut hormone glucagon-like peptide-1, enhancing insulin secretion, suppressing appetite, and slowing gastric emptying. Their clinical success in metabolic disease has been extraordinary, but researchers have increasingly recognized that the GLP-1 receptor is not confined to the pancreas and the gut. Receptors for the hormone are found throughout the body, including in the brain, where they participate in insulin signaling, neuroinflammation, and neuronal survival pathways. This widespread expression has fueled speculation that GLP-1-based therapies could have effects far beyond glucose control, with investigations underway in conditions ranging from Parkinson’s disease and Alzheimer’s disease to stroke.

The biological rationale for a neuroprotective role in brain injury is substantial. A 2024 review in Signal Transduction and Targeted Therapy catalogued the mechanisms and therapeutic advances surrounding the GLP-1 receptor, highlighting its involvement in anti-inflammatory and cytoprotective signaling. The brain itself is an insulin-sensitive metabolic organ, as researchers Milstein and Ferris argued in Molecular Metabolism in 2021, meaning that metabolic hormones can directly influence neuronal function and resilience. In the context of trauma, this matters because the injured brain undergoes profound metabolic disruption: glucose metabolism becomes dysregulated, mitochondrial function falters, and the energy demands of repair collide with a compromised supply. Drugs that modulate insulin signaling and cellular stress responses could, in principle, tip the balance toward recovery rather than deterioration.

Laboratory studies have lent concrete support to that idea. In work published in PLOS ONE in 2015, Hakon and colleagues showed that liraglutide, a long-acting GLP-1 analogue, preserved the blood-brain barrier and protected cortical neuronal tissue after experimental traumatic brain injury in animal models. The blood-brain barrier is a critical structure that normally shields the brain from circulating blood components, and its breakdown after trauma is a central driver of cerebral edema, or swelling, which can be lethal. A companion study by Li and colleagues in the Journal of Neurochemistry the same year found that liraglutide was neurotrophic and neuroprotective in neuronal cultures and mitigated mild traumatic brain injury in mice, promoting neuronal survival and repair. An accompanying commentary by Combs asked directly whether GLP-1 receptor agonists might be useful against traumatic brain injury, capturing the excitement that these findings generated in the neurotrauma community.

What has been missing is human evidence. Animal models of brain injury have a notoriously poor track record of translating into effective treatments for patients, with numerous once-promising neuroprotective agents failing in clinical trials. The new study from the Taiwanese team therefore represents an important step in the translational chain, moving from rodent experiments to the analysis of real-world outcomes in surgically treated patients. By examining whether patients who were taking GLP-1 receptor agonists around the time of their brain injury surgery fared differently from those who were not, the researchers sought to test whether the laboratory promise of these drugs survives contact with clinical reality.

The study’s focus on surgically treated patients is notable for several reasons. First, this population represents a severe end of the traumatic brain injury spectrum, in which the injury burden is high enough to warrant operative management, and mortality risk is correspondingly elevated. Second, surgical patients are a relatively well-defined cohort, with clear timestamps for intervention, which helps researchers anchor their analyses. Third, as a TRACK-TBI study published in JAMA Surgery in 2024 by Roberts and colleagues demonstrated, exposure to extracranial surgery and the systemic effects of trauma and operations can significantly shape outcomes after brain injury, underscoring the importance of accounting for the overall clinical context when evaluating any potential therapeutic association. The new analysis, approved by an institutional review board and conducted without specific external funding, was published as a brief communication, a format typically reserved for concise, focused findings rather than large definitive trials.

The authors report an association between GLP-1 receptor agonist use and survival in this surgical population, a finding that, if confirmed, would suggest that the neuroprotective effects observed in the laboratory extend to humans. The researchers are careful to frame the work as an association study rather than a demonstration of causation. Patients who take GLP-1 receptor agonists are, by definition, a selected group, most commonly individuals with type 2 diabetes or obesity, and their underlying health profiles, comorbidities, and medical management differ in many ways from those of patients not taking the drugs. Disentangling whether any survival advantage stems from the drug itself, from better metabolic control, from differences in baseline health, or from some combination of these factors requires the kind of rigorous controlled comparison that only prospective randomized trials can provide. The authors declare no competing financial interests, and artificial intelligence was not used in the preparation of the manuscript.

Nevertheless, the implications of the finding are considerable. GLP-1 receptor agonists are among the most widely used medications in the world, with tens of millions of patients taking them for diabetes, obesity, and increasingly for cardiovascular and kidney protection. If even a modest survival benefit after traumatic brain injury were confirmed, the public health impact could be substantial, given the enormous global burden of head trauma from falls, road traffic collisions, and violence. The finding would also add to a rapidly expanding list of potential indications for this drug class, which researchers are already exploring in neurodegenerative disease, addiction, and other areas of neuroscience. The convergence of metabolic and neurological medicine, once a niche intersection, is becoming one of the most active frontiers in drug repurposing.

The path forward will likely involve several parallel efforts. Larger retrospective analyses across independent patient cohorts could test whether the association holds in different populations and health systems. Prospective studies could examine whether pre-injury GLP-1 receptor agonist use correlates with reduced cerebral edema, improved imaging markers, or altered inflammatory profiles in the acute phase of injury. Ultimately, randomized trials testing GLP-1-based therapy after brain injury, whether in patients already taking the drugs or as a new therapeutic intervention, would be needed to establish causation and define optimal timing, dosing, and patient selection. For now, the study stands as a compelling early signal that a drug class designed to treat metabolic disease may also help the injured brain survive, a possibility that laboratory scientists anticipated a decade ago and that clinical researchers are only now beginning to test in patients.

Subject of Research: Association between GLP-1 receptor agonist use and survival in surgically treated traumatic brain injury patients

Article Title: Association Between GLP-1 RECEPTOR Agonist use and Survival in Surgically Treated Patients with Traumatic Brain Injury

Article References: Khor, W.-T., Chi, K.-Y., Chang, Y., Perng, P.-S., Lin, H.-M., Huang, Y.-T., & Huang, C.-Y. (2026). Association Between GLP-1 RECEPTOR Agonist use and Survival in Surgically Treated Patients with Traumatic Brain Injury. Neurocritical Care. https://doi.org/10.1007/s12028-026-02676-z

Image Credits: AI Generated

DOI: 10.1007/s12028-026-02676-z

Keywords: GLP-1 receptor agonists, traumatic brain injury, neuroprotection, survival, neurocritical care, liraglutide, blood-brain barrier, type 2 diabetes, neuroinflammation, drug repurposing, brain surgery, insulin signaling