Do Neuroprognostic Studies Account for Self-Fulfilling Prophecy Bias in Their Methodology? The SPIN Protocol for a Systematic Review.

Self-fulfilling prophecy bias occurs when a perceived prognosis leads to treatment decisions that inherently modify outcomes of a patient, and thus, overinflate the prediction performance of prognostic methods. The goal of this series of systematic reviews is to characterize the extent to which neuroprognostic studies account for the potential impact of self-fulfilling prophecy bias in their methodology by assessing their adequacy of disclosing factors relevant to this bias. Methods: Studies evaluating the prediction performance of neuroprognostic tools in cardiac arrest, malignant ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, and spontaneous intracerebral hemorrhage will be identified through PubMed, Cochrane, and Embase database searches. Two reviewers blinded to each other's assessment will perform screening and data extraction of included studies using Distiller SR and following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We will abstract data pertinent to the methodology of the studies relevant to self-fulfilling prophecy bias. Results: We will conduct a descriptive analysis of the data. We will summarize the reporting of mortality according to timing and mode of death, rates of exposure to withdrawal of life-sustaining therapy, reasoning behind limitations of supportive care, systematic use of standardized neuroprognostication algorithms and whether the tool being investigated is part of such assessments, and blinding of treatment team to results of neuroprognostic test being evaluated. CONCLUSIONS: We will identify if neuroprognostic studies have been transparent in their methodology to factors that affect the self-fulfilling prophecy bias. Our results will serve as the foundation for standardization of neuroprognostic study methodologies by refining the quality of the data derived from such studies.

5-Fluorouracil Neurotoxicity in the Absence of Dihydropyrimidine Dehydrogenase Deficiency Case Report.

5 fluorouracil (5-FU)-related neurotoxicity is a rare and severe complication of 5-FU administration. Dihydropyrimidine dehydrogenase (DPD) deficiency is associated with an increased risk of serious adverse reactions due to its role in 5-FU metabolism. We report a case of acute reversible neurotoxicity with global areas of diffusion restriction in a patient with colorectal adenocarcinoma being treated with leucovorin calcium, 5-fluorouracil, and oxaliplatin (FOLFOX) without DPD deficiency following uridine triacetate administration.

Pregabalin for Recurrent Seizures in Critical Illness: A Promising Adjunctive Therapy, Especially for cyclic Seizures.

BACKGROUND: Pregabalin (PGB) is an effective adjunctive treatment for focal epilepsy and acts by binding to the alpha2-delta subunit of voltage-gated calcium channels to reduce excitatory neurotransmitter release. Limited data exist on its use in the neurocritical care setting, including cyclic seizures-a pattern of recurrent seizures occurring at nearly regular intervals. Although the mechanism underpinning cyclic seizures remains elusive, spreading excitation linked to spreading depolarizations may play a role in seizure recurrence and periodicity. PGB has been shown to increase spreading depolarization threshold; hence, we hypothesized that the magnitude of antiseizure effect from PGB is more pronounced in patients with cyclic versus noncyclic seizures in a critically ill cohort with recurrent seizures. METHODS: We conducted a retrospective case series of adults admitted to two academic neurointensive care units between January 2017 and March 2019 who received PGB for treatment of seizures. Data collected included demographics, etiology of brain injury, antiseizure medications, and outcome. Continuous electroencephalogram recordings 48 hours before and after PGB administration were reviewed by electroencephalographers blinded to the administration of antiseizure medications to obtain granular data on electrographic seizure burden. Cyclic seizures were determined quantitatively (i.e., < 50% variation of interseizure intervals for at least 50% of consecutive seizures). Coprimary outcomes were decrease in hourly seizure burden in minutes and decrease in seizure frequency in the 48 hours after PGB initiation. We used nonparametric tests for comparison of seizure frequency and burden and segmented linear regression to assess PGB effect. RESULTS: We included 16 patients; the median age was 69 years, 11 (68.7%) were women, three (18.8%) had undergone a neurosurgical procedure, and five (31%) had underlying epilepsy. All seizures had focal onset; ten patients (62.5%) had cyclic seizures. The median hourly seizure burden over the 48 hours prior to PGB initiation was 1.87 min/hour (interquartile range 1.49-8.53), and the median seizure frequency was 1.96 seizures/hour (interquartile range 1.06-3.41). In the 48 hours following PGB (median daily dose 300 mg, range 75-300 mg), the median number of seizures per hour was reduced by 0.80 seizures/hour (95% confidence interval 0.19-1.40), whereas the median hourly seizure burden decreased by 1.71 min/hour (95% confidence interval 0.38-3.04). When we compared patients with cyclic versus noncyclic seizures, there was a relative decrease in hourly seizure frequency (- 86.7% versus - 2%, p = 0.04) and hourly seizure burden (- 89% versus - 7.8%, p = 0.03) at 48 hours. CONCLUSIONS: PGB was associated with a relative reduction in seizure burden in neurocritically ill patients with recurrent seizures, especially those with cyclic seizures, and may be considered in the therapeutic arsenal for refractory seizures. Whether this effect is mediated via modulation of spreading depolarization requires further study.

Does intrathecal nicardipine for cerebral vasospasm following subarachnoid hemorrhage correlate with reduced delayed cerebral ischemia? A retrospective propensity score-based analysis.

OBJECTIVE: Cerebral vasospasm and delayed cerebral ischemia (DCI) contribute to poor outcome following subarachnoid hemorrhage (SAH). With the paucity of effective treatments, the authors describe their experience with intrathecal (IT) nicardipine for this indication. METHODS: Patients admitted to the Emory University Hospital neuroscience ICU between 2012 and 2017 with nontraumatic SAH, either aneurysmal or idiopathic, were included in the analysis. Using a propensity-score model, this patient cohort was compared to patients in the Subarachnoid Hemorrhage International Trialists (SAHIT) repository who did not receive IT nicardipine. The primary outcome was DCI. Secondary outcomes were long-term functional outcome and adverse events. RESULTS: The analysis included 1351 patients, 422 of whom were diagnosed with cerebral vasospasm and treated with IT nicardipine. When compared with patients with no vasospasm (n = 859), the treated group was significantly younger (mean age 51.1 ± 12.4 years vs 56.7 ± 14.1 years, p < 0.001), had a higher World Federation of Neurosurgical Societies score and modified Fisher grade, and were more likely to undergo clipping of the ruptured aneurysm as compared to endovascular treatment (30.3% vs 11.3%, p < 0.001). Treatment with IT nicardipine decreased the daily mean transcranial Doppler velocities in 77.3% of the treated patients. When compared to patients not receiving IT nicardipine, treatment was not associated with an increased rate of bacterial ventriculitis (3.1% vs 2.7%, p > 0.1), yet higher rates of ventriculoperitoneal shunting were noted (19.9% vs 8.8%, p < 0.01). In a propensity score comparison to the SAHIT database, the odds ratio (OR) to develop DCI with IT nicardipine treatment was 0.61 (95% confidence interval [CI] 0.44-0.84), and the OR to have a favorable functional outcome (modified Rankin Scale score ≤ 2) was 2.17 (95% CI 1.61-2.91). CONCLUSIONS: IT nicardipine was associated with improved outcome and reduced DCI compared with propensity-matched controls. There was an increased need for permanent CSF diversion but no other safety issues. These data should be considered when selecting medications and treatments to study in future randomized controlled clinical trials for SAH.

The Modified Early Warning Score: A Useful Marker of Neurological Worsening but Unreliable Predictor of Sepsis in the Neurocritically Ill-A Retrospective Cohort Study.

To determine the performance of the Modified Early Warning Score and Modified Early Warning Score-Sepsis Recognition Score to predict sepsis, morbidity, and mortality in neurocritically ill patients. DESIGN: Retrospective cohort study. SETTING: Single tertiary-care academic medical center. PATIENTS: Consecutive adult patients admitted to the neuro-ICU from January 2013 to December 2016. INTERVENTIONS: Observational study. MEASUREMENTS AND MAIN RESULTS: Baseline and clinical characteristics, infections/sepsis, neurologic worsening, and mortality were abstracted. Primary outcomes included new infection/sepsis, escalation of care, and mortality. Patients with Modified Early Warning Score-Sepsis Recognition Score/Modified Early Warning Score greater than or equal to 5 were compared with those with scores less than 5. 5. Of 7,286 patients, Of 7,286 patients, 1,120 had Modified Early Warning Score-Sepsis Recognition Score greater than or equal to 5. Of those, mean age was 58.9 years; 50.2% were male. Inhospitality mortality was 22.1% for patients (248/1,120) with Modified Early Warning Score-Sepsis Recognition Score greater than or equal to 5, compared with 6.1% (379/6,166) with Modified Early Warning Score-Sepsis Recognition Score less than 5. Sepsis was present in 5.6% (345/6,166) when Modified Early Warning Score-Sepsis Recognition Score less than 5 versus 14.3% (160/1,120) when greater than or equal to 5, and Modified Early Warning Score elevation led to a new sepsis diagnosis in 5.5% (62/1,120). Three-hundred forty-three patients (30.6%) had neurologic worsening at the time of Modified Early Warning Score-Sepsis Recognition Score elevation. Utilizing the original Modified Early Warning Score, results were similar, with less score thresholds met (836/7,286) and slightly weaker associations. CONCLUSIONS: In neurocritical ill patients, Modified Early Warning Score-Sepsis Recognition Score and Modified Early Warning Score are associated with higher inhospital mortality and are preferentially triggered in setting of neurologic worsening. They are less reliable in identifying new infection or sepsis in this patient population. Population-specific adjustment of early warning scores may be necessary for the neurocritically ill patient population.

Evaluation and Management of Seizures and Status Epilepticus.

Seizures are frequently triggered by an inciting event and result from uninhibited excitation and/or decreased inhibition of a pool of neurons. If physiologic seizure abortive mechanisms fail, the ensuing unrestrained synchronization of neurons-status epilepticus-can be life-threatening and is associated with the potential for marked morbidity in survivors and high medical care costs. Prognosis is intimately related to etiology and its response to therapeutic measures. Timely implementation of pharmacologic therapy while concurrently performing a stepwise workup for etiology are paramount. Neurodiagnostic testing should guide titration of pharmacologic therapies, and help determine if there is a role for immune modulation.

Role of vasopressin and its antagonism in stroke related edema.

Although many approaches have been tried in the attempt to reduce the devastating impact of stroke, tissue plasminogen activator for thromboembolic stroke is the only proved, effective acute stroke treatment to date. Vasopressin, an acute-phase reactant, is released after brain injury and is partially responsible for the subsequent inflammatory response via activation of divergent pathways. Recently there has been increasing interest in vasopressin because it is implicated in inflammation, cerebral edema, increased intracerebral pressure, and cerebral ion and neurotransmitter dysfunctions after cerebral ischemia. Additionally, copeptin, a byproduct of vasopressin production, may serve as a promising independent marker of tissue damage and prognosis after stroke, thereby corroborating the role of vasopressin in acute brain injury. Thus, vasopressin antagonists have a potential role in early stroke intervention, an effect thought to be mediated via interactions with aquaporin receptors, specifically aquaporin-4. Despite some ambiguity, vasopressin V1a receptor antagonism has been consistently associated with attenuated secondary brain injury and edema in experimental stroke models. The role of the vasopressin V2 receptor remains unclear, but perhaps it is involved in a positive feedback loop for vasopressin expression. Despite the encouraging initial findings we report here, future research is required to characterize further the utility of vasopressin antagonists in treatment of stroke.

Effect of acetazolamide on aquaporin-1 and fluid flow in cultured choroid plexus.

Acetazolamide (AZA), used in treatment of early or infantile hydrocephalus, is effective in some cases, while its effect on the choroid plexus (CP) remains ill-defined. The drug reversibly inhibits aquaporin-4 (AQP4), the most ubiquitous "water pore" in the brain, and perhaps modulation of AQP1 (located apically on CP cells) by AZA may reduce cerebrospinal fluid (CSF) production. We sought to elucidate the effect of AZA on AQP1 and fluid flow in CP cell cultures.CP tissue culture from 10-day Sprague-Dawley rats and a TRCSF-B cell line were grown on Transwell permeable supports and treated with 100 µM AZA. Fluid assays to assess direction and extent of fluid flow, and AQP1 expression patterns by immunoblot, Immuncytochemistry (ICC), and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) were performed.Immunoblots and ICC analyses showed a decrease in AQP1 protein shortly after AZA treatment (lowest at 12 h), with transient AQP1 reduction mediated by mRNA expression (lowest at 6 h). Transwell fluid assays indicated a fluid shift at 2 h, before significant changes in AQP1 mRNA or protein levels.Timing of AZA effect on AQP1 suggests the drug alters protein transcription, while affecting fluid flow by a concomitant method. It is plausible that other mechanisms account for these phenomena, as the processes may occur independently.