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The field of human space travel is in the midst of a dramatic revolution. Upcoming missions are looking to push the boundaries of space travel, with plans to travel for longer distances and durations than ever before. Both the National Aeronautics and Space Administration (NASA) and several commercial space companies (e.g., Blue Origin, SpaceX, Virgin Galactic) have already started the process of preparing for long-distance, long-duration space exploration and currently plan to explore inner solar planets (e.g., Mars) by the 2030s. With the emergence of space tourism, space travel has materialized as a potential new, exciting frontier of business, hospitality, medicine, and technology in the coming years. However, current evidence regarding human health in space is very limited, particularly pertaining to short-term and long-term space travel. This review synthesizes developments across the continuum of space health including prior studies and unpublished data from NASA related to each individual organ system, and medical screening prior to space travel. We categorized the extraterrestrial environment into exogenous (e.g., space radiation and microgravity) and endogenous processes (e.g., alteration of humans' natural circadian rhythm and mental health due to confinement, isolation, immobilization, and lack of social interaction) and their various effects on human health. The aim of this review is to explore the potential health challenges associated with space travel and how they may be overcome in order to enable new paradigms for space health, as well as the use of emerging Artificial Intelligence based (AI) technology to propel future space health research. [ABSTRACT FROM AUTHOR]

Neuro-ocular changes during long-duration space flight are known as spaceflight-associated neuro-ocular syndrome (SANS). The ability to detect, monitor, and prevent SANS is a priority of current space medicine research efforts. Optic nerve sheath diameter (ONSD) measurement has been used both terrestrially and in microgravity as a proxy for measurements of elevated intracranial pressure. ONSD shows promise as a potential method of identifying and quantitating neuro-ocular changes during space flight. This review examines 13 studies measuring ONSD and its relationship to microgravity exposure or ground-based analogs, including head-down tilt, dry immersion, or animal models. The goal of this correspondence is to describe heterogeneity in the use of ONSD in the current SANS literature and make recommendations to reduce heterogeneity in future studies through standardization of imaging modalities, measurement techniques, and other aspects of study design. [ABSTRACT FROM AUTHOR]

Spaceflight associated neuro‐ocular syndrome (SANS) is hypothesized to develop as a consequence of the chronic headward fluid shift that occurs in sustained weightlessness. We exposed healthy subjects (n = 24) to strict 6° head‐down tilt bed rest (HDTBR), an analog of weightlessness that generates a sustained headward fluid shift, and we monitored for ocular changes similar to findings that develop in SANS. Two‐thirds of the subjects received a daily 30‐min exposure to artificial gravity (AG, 1 g at center of mass, ~0.3 g at eye level) during HDTBR by either continuous (cAG, n = 8) or intermittent (iAG, n = 8) short‐arm centrifugation to investigate whether this intervention would attenuate headward fluid shift‐induced ocular changes. Optical coherence tomography images were acquired to quantify changes in peripapillary total retinal thickness (TRT), retinal nerve fiber layer thickness, and choroidal thickness, and to detect chorioretinal folds. Intraocular pressure (IOP), optical biometry, and standard automated perimetry data were collected. TRT increased by 35.9 µm (95% CI, 19.9–51.9 µm, p < 0.0001), 36.5 µm (95% CI, 4.7–68.2 µm, p = 0.01), and 27.6 µm (95% CI, 8.8–46.3 µm, p = 0.0005) at HDTBR day 58 in the control, cAG, and iAG groups, respectively. Chorioretinal folds developed in six subjects across the groups, despite small increases in IOP. Visual function outcomes did not change. These findings validate strict HDTBR without elevated ambient CO2 as a model for investigating SANS and suggest that a fluid shift reversal of longer duration and/or greater magnitude at the eye may be required to prevent or mitigate SANS. [ABSTRACT FROM AUTHOR]

Background: Rapid diagnosis and proper management of intracerebral hemorrhage (ICH) play a crucial role in the outcome. Prediction of the outcome with a high degree of accuracy based on admission data including imaging information can potentially influence clinical decision-making practice.Methods: We conducted a retrospective multicenter study of consecutive ICH patients admitted between 2012-2017. Medical history, admission data, and initial head computed tomography (CT) scan were collected. CT scans were semiautomatically segmented for hematoma volume, hematoma density histograms, and sphericity index (SI). Discharge unfavorable outcomes were defined as death or severe disability (modified Rankin Scores 4-6). We compared (1) hematoma volume alone; (2) multiparameter imaging data including hematoma volume, location, density heterogeneity, SI, and midline shift; and (3) multiparameter imaging data with clinical information available on admission for ICH outcome prediction. Multivariate analysis and predictive modeling were used to determine the significance of hematoma characteristics on the outcome.Results: We included 430 subjects in this analysis. Models using automated hematoma segmentation showed incremental predictive accuracies for in-hospital mortality using hematoma volume only: area under the curve (AUC): 0.85 [0.76-0.93], multiparameter imaging data (hematoma volume, location, CT density, SI, and midline shift): AUC: 0.91 [0.86-0.97], and multiparameter imaging data plus clinical information on admission (Glasgow Coma Scale (GCS) score and age): AUC: 0.94 [0.89-0.99]. Similarly, severe disability predictive accuracy varied from AUC: 0.84 [0.76-0.93] for volume-only model to AUC: 0.88 [0.80-0.95] for imaging data models and AUC: 0.92 [0.86-0.98] for imaging plus clinical predictors.Conclusions: Multiparameter models combining imaging and admission clinical data show high accuracy for predicting discharge unfavorable outcome after ICH. [ABSTRACT FROM AUTHOR]

Spontaneous intracerebral hemorrhage (ICH) is a devastating form of stroke, with a high rate of mortality and morbidity. Even with the best current medical or surgical interventions, outcomes remain poor. The location and initial hematoma volume are strong predictors of mortality. Hematoma expansion (HE) is a further marker of poor prognosis that may be at least partly preventable. Several risk factors for HE have been identified, including baseline ICH volume, anticoagulation, and computed tomography angiography spot signs. Recent studies have shown the correlation of serum calcium (Ca++) levels on admission with HE. Low serum Ca++ level has been associated with larger hematoma volume at the time of presentation, HE, and worse outcome. Although the causal and mechanistic links between low serum Ca++ level and HE are not well understood, several mechanisms have been proposed including coagulopathy, platelet dysfunction, and higher blood pressure (BP) in the context of low serum Ca++ level. However, low serum Ca++ level might be only a biomarker of the adaptive response due to acute inflammatory response following acute ICH. The purpose of the current review is to discuss the evidence regarding the possible role of low serum Ca++ level on HE in acute ICH. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is a need to develop noninvasive methods to monitor intracranial pressure (ICP). Pupillary reactivity decreases in patients with elevated ICP with demonstrated cerebral edema. We sought to determine whether pupillary reactivity is affected when ICP is elevated in the absence of brain edema. METHODS: Healthy subjects and individuals with idiopathic intracranial hypertension (IIH) underwent pupillometry in different positions (upright, supine, and head-down tilt) and during different physiological maneuvers. A separate group of healthy subjects were tested in the upright resting position only. The pupillary dynamics were measured with a pupillometer. RESULTS: Healthy and IIH subjects were enrolled. In the healthy subjects the change from upright to head-down tilt led to a Neurological Pupil Index (NPI) decrease from 4.30 to 4.12, while maximum pupil size and minimum pupil size increased from 4.74 to 5.19 and 3.04 to 3.44, respectively. In the IIH group the maximum pupil size, minimum pupil size, and latency increased in magnitude with a decline in head tilt. The mean NPI of IIH subjects, 4.37, was greater than the healthy mean, 4.25. Also, the mean IIH Max and Min, 5.02 and 3.25, were greater than the healthy mean, 4.62 and 2.92. DISCUSSION: We observed changes in the pupillary reactivity in all subjects based on changes in position and task. There were also differences between the healthy and IIH subjects. This is consistent with our hypothesis that elevated intracranial pressure may result in decreased pupillary reactivity even in the absence of brain edema. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to examine the incidence of the oculocardiac reflex during a non-invasive intracranial pressure measurement when gradual external pressure was applied to the orbital tissues and eye. Methods: Patients (n = 101) and healthy volunteers (n = 56) aged 20–75 years who underwent a non-invasive intracranial pressure measurement were included in this retrospective oculocardiac reflex analysis. Prespecified thresholds greater than a 10% or 20% decrease in the heart rate from baseline were used to determine the incidence of the oculocardiac reflex. Results: None of the subjects had a greater than 20% decrease in heart rate from baseline. Four subjects had a greater than 10% decrease in heart rate from baseline, representing 0.9% of the total pressure steps. Three of these subjects were healthy volunteers, and one was a glaucoma patient. Conclusion: The incidence of the oculocardiac reflex during a non-invasive intracranial pressure measurement procedure was very low and not associated with any clinically relevant effects. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cerebral hemodynamics and venous outflow from the brain may be altered during exposure to microgravity or head-down tilt (HDT), an analog of microgravity, as well as by increased ambient CO2 exposure as experienced on the International Space Station. METHODS: Six healthy subjects underwent baseline tilt table testing at 0°, 6°, 12°, 18°, 24°, and 30° HDT. The right internal jugular (IJ) vein cross-sectional area (CSA) was measured at four intervals from the submandibular to the clavicular level and IJ volume was calculated. Further measurements of the IJ vein were made after ~26 h of 12° HDT bed rest with either ambient air or 0.5% CO2 exposure, and plasma and blood volume were assessed after 4 h, 24 h, and 28.5 h HDT. RESULTS: IJ vein CSA and volume increased with progressively steeper HDT angles during baseline tilt table testing, with more prominent filling of the IJ vein at levels closer to the clavicle. Exposure to 26 h of 12° HDT bed rest with or without increased CO2, however, had little additional effect on the IJ vein. Further, bed rest resulted in a decrease in plasma volume and blood volume, although changes did not depend on atmospheric conditioning or correlate directly with changes in IJ vein CSA or volume. DISCUSSION: The hydrostatic effects of HDT can be clearly determined through measurement of the IJ vein CSA and volume; however, IJ vein dimensions may not be a reliable indicator of systemic fluid status during bed rest. [ABSTRACT FROM AUTHOR]

Microgravity and elevated levels of CO2 are two common environmental stressors in spaceflight that may affect cognitive performance of astronauts. In this randomized, double-blind, crossover trial (SPACECOT), 6 healthy males (mean ± SD age: 41 ± 5 yr) were exposed to 0.04% (ambient air) and 0.5% CO2 concentrations during 26.5-h periods of 12° head-down tilt (HDT) bed rest with a 1-wk washout period between exposures. Subjects performed the 10 tests of the Cognition Test Battery before and on average 0.1, 5.2, and 21.0 h after the initiation of HDT bed rest. HDT in ambient air induced a change in response strategy, with increased response speed (+0.19 SD; P = 0.0254) at the expense of accuracy (-0.19 SD; P = 0.2867), resulting in comparable cognitive efficiency. The observed effects were small and statistically significant for cognitive speed only. However, even small declines in accuracy can potentially cause errors during mission-critical tasks in spaceflight. Unexpectedly, exposure to 0.5% CO2 reversed the response strategy changes observed under HDT in ambient air. This was possibly related to hypercapnia-induced cerebrovascular reactivity that favors cortical regions in general and the frontal cortex in particular, or to the CNS arousing properties of mildly to moderately increased CO2 levels. There were no statistically significant time-in-CO2 effects for any cognitive outcome. The small sample size and the small effect sizes are major limitations of this study and its findings. The results should not be generalized beyond the group of investigated subjects until they are confirmed by adequately powered follow-up studies. NEW & NOTEWORTHY Simulating microgravity with exposure to 21 h of 12° head-down tilt bed rest caused a change in response strategy on a range of cognitive tests, with a statistically significant increase in response speed at the expense of accuracy. Cognitive efficiency was not affected. The observed speed-accuracy tradeoff was small but may nevertheless be important for mission-critical tasks in spaceflight. Importantly, the change in response strategy was reversed by increasing CO2 concentrations to 0.5%. [ABSTRACT FROM AUTHOR]

Background: Cerebral edema, which is associated with increased intracranial fluid, is often a complication of many acute neurological conditions. There is currently no accepted method for real-time monitoring of intracranial fluid volume at the bedside. We evaluated a novel noninvasive technique called "Volumetric Integral Phase-shift Spectroscopy (VIPS)" for detecting intracranial fluid shifts during hemodialysis.Methods: Subjects receiving scheduled hemodialysis for end-stage renal disease and without a history of major neurological conditions were enrolled. VIPS monitoring was performed during hemodialysis. Serum osmolarity, electrolytes, and cognitive function with mini-mental state examination (MMSE) were assessed.Results: Twenty-one monitoring sessions from 14 subjects (4 women), mean group age 50 (SD 12.6), were analyzed. The serum osmolarity decreased by a mean of 6.4 mOsm/L (SD 6.6) from pre- to post-dialysis and correlated with an increase in the VIPS edema index (E-Dex) of 9.7% (SD 12.9) (Pearson's correlation r = 0.46, p = 0.037). Of the individual determinants of serum osmolarity, changes in serum sodium level correlated best with the VIPS edema index (Pearson's correlation, r = 0.46, p = 0.034). MMSE scores did not change from pre- to post-dialysis.Conclusions: We detected an increase in the VIPS edema index during hemodialysis that correlated with decreased serum osmolarity, mainly reflected by changes in serum sodium suggesting shifts in intracranial fluids. [ABSTRACT FROM AUTHOR]

Astronauts aboard the International Space Station (ISS) have exhibited hyperopic shifts, posterior eye globe flattening, dilated optic nerve sheaths, and even optic disk swelling from spaceflight. Elevated intracranial pressure (ICP) consequent to cephalad fluid shifts is commonly hypothesized as contributing to these ocular changes. Head-down tilt (HDT) is frequently utilized as an Earth-based analog to study similar fluid shifts. Sealed environments like the ISS also exhibit elevated CO2, a potent arteriolar vasodilator that could further affect cerebral blood volume (CBV) and cerebral blood flow, intracranial compliance, and ICP. A collaborative pilot study between the National Space Biomedical Research Institute and the German Aerospace Center tested the hypotheses that 1) HDT and elevated CO2 physiologically interact and 2) cerebrovascular pulsatility is related to HDT and/or elevated CO2. In a doubleblind crossover study (n = 6), we measured CBV pulsatility via near-infrared spectroscopy, alongside noninvasive ICP and intraocular pressure (IOP) during 28-h -12° HDT at both nominal (0.04%) and elevated (0.5%) ambient CO2. In our cohort, CBV pulsatility increased significantly over time at cardiac frequencies (0.031 ± 0.009 μM/h increase in total hemoglobin concentration pulsatility amplitude) and Mayer wave frequencies (0.019 ± 0.005 μM/h increase). The HDT-CO2 interaction on pulsatility was not robust but rather driven by one individual. Significant differences between atmospheres were not detected in ICP or IOP. Further work is needed to determine whether individual differences in pulsatility responses to CO2 relate to visual changes in space. [ABSTRACT FROM AUTHOR]

Exposure to the microgravity environment results in various adaptive and maladaptive physiological changes in the human body, with notable ophthalmic abnormalities developing during 6-mo missions on the International Space Station (ISS). These findings have led to the hypothesis that the loss of gravity induces a cephalad fluid shift, decreased cerebral venous outflow, and increased intracranial pressure, which may be further exacerbated by increased ambient carbon dioxide (CO2) levels on the ISS. Here we describe the SPACECOT study (studying the physiological and anatomical cerebral effects of CO2 during head-down tilt), a randomized, doubleblind crossover design study with two conditions: 29 h of 12° head-down tilt (HDT) with ambient air and 29 h of 12° HDT with 0.5% CO2. The internationally collaborative SPACECOT study utilized an innovative approach to study the effects of headward fluid shifting induced by 12° HDT and increased ambient CO2 as well as their interaction with a focus on cerebral and ocular anatomy and physiology. Here we provide an in-depth overview of this new approach including the subjects, study design, and implementation, as well as the standardization plan for nutritional intake, environmental parameters, and bed rest procedures. NEW & NOTEWORTHY A new approach for investigating the combined effects of cephalad fluid shifting and increased ambient carbon dioxide (CO2) is presented. This may be useful for studying the neuroophthalmic and cerebral effects of spaceflight where cephalad fluid shifts occur in an elevated CO2 environment. [ABSTRACT FROM AUTHOR]

To improve the pathophysiological understanding of visual changes observed in astronauts, we aimed to use quantitative MRI to measure anatomic and physiological responses during a ground-based spaceflight analog (head-down tilt, HDT) combined with increased ambient carbon dioxide (CO2). Six healthy, male subjects participated in the double-blinded, randomized crossover design study with two conditions: 26.5 h of −12° HDT with ambient air and with 0.5% CO2, both followed by 2.5-h exposure to 3% CO2. Volume and mean diffusivity quantification of the lateral ventricle and phase-contrast flow sequences of the internal carotid arteries and cerebral aqueduct were acquired at 3 T. Compared with supine baseline, HDT (ambient air) resulted in an increase in lateral ventricular volume (P = 0.03). Cerebral blood flow, however, decreased with HDT in the presence of either ambient air or 0.5% CO2 (P = 0.002 and P = 0.01, respectively); this was partially reversed by acute 3% CO2 exposure. Following HDT (ambient air), exposure to 3% CO2 increased aqueductal cerebral spinal fluid velocity amplitude (P = 0.01) and lateral ventricle cerebrospinal fluid (CSF) mean diffusivity (P = 0.001). We concluded that HDT causes alterations in cranial anatomy and physiology that are associated with decreased craniospinal compliance. Brief exposure to 3% CO2 augments CSF pulsatility within the cerebral aqueduct and lateral ventricles. NEW & NOTEWORTHY Head-down tilt causes increased lateral ventricular volume and decreased cerebrovascular flow after 26.5 h. Additional short exposure to 3% ambient carbon dioxide levels causes increased cerebrovascular flow associated with increased cerebrospinal fluid pulsatility at the cerebral aqueduct. Head-down tilt with chronically elevated 0.5% ambient carbon dioxide and acutely elevated 3% ambient carbon dioxide causes increased mean diffusivity of cerebral spinal fluid within the lateral ventricles. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis To determine the degree to which balance is impaired by fatigue in postcall medical residents and to assess the validity of posturography in quantifying that impairment. Study Design Prospective study. Methods Medical residents underwent the following tests before and immediately after overnight call: 1) computerized dynamic posturography (CDP) using the Equitest force platform (Natus Medical Inc., Clackamas, OR); 2) Clinical Test of Sensory Interaction and Balance, in which the residents stood on a compliant foam mat with closed eyes and flexed and extended their necks; 3) a computerized reaction time test (available at ). All tests were performed before and after call at approximately the same time of day to exclude circadian rhythm influence on fatigue. The residents also completed questionnaires, including the Stanford Sleepiness Scale, describing their level of fatigue before and after call. Results A statistically significant difference was found between a resident's pre- and postcall test with regard to reaction time ( P = .01), Stanford Sleepiness Scale score ( P = .001), and preference for the visual system as measured by CDP ( P = .05). Linear regression analysis showed a statistically significant relationship between sleep deprivation and multiple performance variables measured by CDP. Conclusions With the growing attention paid to resident duty hours, there is an increasing need for research involving fatigue and practical ways to measure it. This study shows that residents who are measurably fatigued (both objectively and subjectively) may have difficulty utilizing vestibular input during quiet standing but can compensate by means of somatosensory and visual input. Level of Evidence NA Laryngoscope, 125:337-341, 2015 [ABSTRACT FROM AUTHOR]

Abstract: The SILK flow diverter (SFD; Balt Extrusion, Montmorency, France) is a flow diverting stent used in the endovascular treatment of intracranial aneurysms. It works on the principle of redirecting flow away from the aneurysm sac, leading to occlusion over time. We present a systematic review on the clinical outcomes and complications of the SFD. A literature search for English language articles were conducted on PubMed, Medline and EMBASE for articles on the treatment of intracranial aneurysms with the SILK flow diverter. The inclusion criteria were n>10, use of SFD only, data on complications and aneurysm occlusion rate (AOR). Eight studies with 285 patients and 317 intracranial aneurysms were included. The mean age was 52.7years and nearly 80% were women. In terms of angiographic distribution, 86.8% of aneurysms were located in the anterior circulation and 13.2% in the posterior circulation. As for the aneurysm size, 37.9% were classed as small, 44.4% as large and 17.7% as giant. Ischemic complications and parent artery occlusion each occurred in 10% of patients. Aneurysm rupture rate was 3.5%, while the cumulative mortality was 4.9%. The main outcome measure, 12month AOR, was 81.8% with complete occlusion in 216 out of 264 aneurysms. Use of flow diverters for the treatment of intracranial aneurysm with complex morphologies has gained in popularity over the last few years. Our review suggests that SFD achieves comparable AOR to its contemporary, the Pipeline Embolization Device (ev3 Endovascular, Plymouth, MN, USA) but has a higher rate of higher rate of ischemic complications, aneurysm rupture and mortality. [Copyright &y& Elsevier]

Abstract: The pipeline embolization device (PED; ev3 Endovascular, Plymouth, MN, USA) is a flow-diverter used in the endovascular treatment of intracranial aneurysms, particularly those with unfavorable configurations. It causes progressive flow redirection leading to aneurysm thrombosis. This study aimed to present a systematic review of the published literature on the clinical outcomes of PED. A Medline search of the English language literature was performed using the keywords “intracranial aneurysms” and “pipeline embolization device” or “flow diverters”. The inclusion criteria were: n>10 patients; unruptured aneurysms; documentation of complications; and at least 3months of follow-up. A total of 13 studies, with 905 patients and 1043 aneurysms, were included. The mean age was 53.8years, with women comprising 76.3% of patients. The mean aneurysm diameter was 11.1mm with 37% classed as large aneurysms and 10% classed as giant. The cumulative mortality rate was 2.3%. Seventeen patients had a stroke (1.9%), while 19 (2.0%) had a transient ischemic attack and 21 patients (2.3%) had an intracranial hemorrhage. The two outcome measures were the cumulative event rate (16.7%) and the 6 month aneurysm occlusion rate (79.7%). A funnel plot with study size plotted against the two outcome measures revealed publication bias. Data from recent studies suggest that complication and mortality rates associated with PED may be similar to other contemporary endovascular techniques, with a better 6 month aneurysm occlusion rate. More prospective clinical trials are warranted to further validate these results. [Copyright &y& Elsevier]

Thrombolytic therapy has revolutionized acute ischemic stroke (AIS) treatment; however it is clear that intravenous (IV) thrombolytic therapy has certain limitations, including a short-time window for use, poor specificity for the site of arterial occlusion, and suboptimal recanalization rates. Some of these problems may be circumvented by using intra-arterial (IA) thrombolysis. In this article, we will discuss the various thrombolytic agents being used in AIS, their mechanisms of actions and doses, and the rationale for use of IA therapy as opposed to IV thrombolysis, and review the clinical trials using IA thrombolysis. We will also discuss other approaches to IA thrombolysis, including mechanical and other endovascular techniques. [ABSTRACT FROM AUTHOR]

Status epilepticus (SE) in adults is a state of continuous seizures lasting more than 5 minutes, or rapidly recurrent seizures without regaining consciousness. The overall US and European estimated crude incidence rate of SE ranges from 6.8 to 41/100,000/yr. The etiologies of SE include primary central nervous system pathologies and systemic disorders. The two basic mechanisms involved in the genesis of SE are an excess of excitatory activity and a loss of normal inhibitory neurotransmission. Mortality associated with SE can be as high as 26% for the average adult. Early recognition and treatment are important for improving the chances for a good out- come. The first line of treatment is an intravenous benzodiazepine, with lorazepam being the current preferred agent. All patients with SE who remain with altered awareness 20 to 30 minutes after cessation of clinical seizures should undergo electroencephalographic studies, because up to 20% of patients without clinical evidence of seizures after initial treatment can have nonconvulsive SE. [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is an autoimmune disorder resulting from the production of antibodies against acetylcholine receptors leading to the destruction of the postsynaptic membrane at the neuromuscular junction. In the US there are about 18,000 people with MG. Myasthenia gravis crisis (MGC) is defined as any MG exacerbation necessitating mechanical ventilation. Most patients presenting with MGC have an identifiable risk factor. The diagnosis of MGC should be suspected in all patients with respiratory failure, particularly those with unclear etiology. Acute management of MGC requires supportive general and ventilatory therapy and institution of measures to improve the neuromuscular blockade. The latter, includes plasma exchange or IV immunoglobulin, and removal of the offending trigger. The outcome of patients with MGC has improved significantly and the current mortality rate is about 4 to 8%. [ABSTRACT FROM AUTHOR]

Objective: The logistics involved in administration of IV tPA for acute ischemic stroke patients are complex, and may contribute to variability in door-to-needle times between different hospitals. We sought to identify practice patterns in stroke centers related to IV tPA use. We hypothesized that there would be significant variability in logistics related to ancillary staff (i.e. nursing, pharmacists) processes in the emergency room setting. Methods: A 21 question survey was distributed to attendees of the AHA/ASA Southwest Affiliate Stroke Coordinators Conference to evaluate potential barriers and delays with regards to thrombolysis for acute strokes patients in the Emergency Department setting. Answers were anonymous and aggregated to examine trends in responses. Results: Responses were obtained from 37 of 67 (55%) stroke centers, which were located mainly in the Southwest United States. Logistical processes differed between facilities. Nursing and pharmacy carried stroke pagers in only 19% of the centers, and pharmacy responded to stroke alerts only one-third of centers. Insertion of Foley catheters and nasogastric tubes prior to tPA was routine in some of the sites. Other barriers to IV tPA administration included physician reluctance and inadequate communication between health care providers. Conclusion: Practices regarding logistics for giving IV tPA may be variable amongst different stroke centers. Given this potential variability, prospective evaluation to confirm these preliminary findings is warranted. [ABSTRACT FROM AUTHOR]