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Dive into the research topics where Gretchen M. Brophy is active.

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Featured researches published by Gretchen M. Brophy.


Neurocritical Care | 2012

Guidelines for the Evaluation and Management of Status Epilepticus

Gretchen M. Brophy; Rodney Bell; Jan Claassen; Brian K. Alldredge; Thomas P. Bleck; Tracy A. Glauser; Suzette M. LaRoche; James J. Riviello; Lori Shutter; Michael R. Sperling; David M. Treiman; Paul Vespa

Status epilepticus (SE) treatment strategies vary substantially from one institution to another due to the lack of data to support one treatment over another. To provide guidance for the acute treatment of SE in critically ill patients, the Neurocritical Care Society organized a writing committee to evaluate the literature and develop an evidence-based and expert consensus practice guideline. Literature searches were conducted using PubMed and studies meeting the criteria established by the writing committee were evaluated. Recommendations were developed based on the literature using standardized assessment methods from the American Heart Association and Grading of Recommendations Assessment, Development, and Evaluation systems, as well as expert opinion when sufficient data were lacking.


Critical Care Medicine | 2010

Ubiquitin C-terminal hydrolase is a novel biomarker in humans for severe traumatic brain injury

Linda Papa; Linnet Akinyi; Ming Cheng Liu; Jose A. Pineda; Joseph J. Tepas; Monika W. Oli; Wenrong Zheng; Gillian Robinson; Steven A. Robicsek; Andrea Gabrielli; Shelley C. Heaton; H. Julia Hannay; Jason A. Demery; Gretchen M. Brophy; Joe Layon; Claudia S. Robertson; Ronald L. Hayes; Kevin K. W. Wang

Objective:Ubiquitin C-terminal hydrolase (UCH-L1), also called neuronal-specific protein gene product (PGP 9.3), is highly abundant in neurons. To assess the reliability of UCH-L1 as a potential biomarker for traumatic brain injury (TBI) this study compared cerebrospinal fluid (CSF) levels of UCH-L1 from adult patients with severe TBI to uninjured controls; and examined the relationship between levels with severity of injury, complications and functional outcome. Design:This study was designed as prospective case control study. Patients:This study enrolled 66 patients, 41 with severe TBI, defined by a Glasgow coma scale (GCS) score of ≤8, who underwent intraventricular intracranial pressure monitoring and 25 controls without TBI requiring CSF drainage for other medical reasons. Setting:Two hospital system level I trauma centers. Measurements and Main Results:Ventricular CSF was sampled from each patient at 6, 12, 24, 48, 72, 96, 120, 144, and 168 hrs following TBI and analyzed for UCH-L1. Injury severity was assessed by the GCS score, Marshall Classification on computed tomography and a complicated postinjury course. Mortality was assessed at 6 wks and long-term outcome was assessed using the Glasgow outcome score 6 months after injury. TBI patients had significantly elevated CSF levels of UCH-L1 at each time point after injury compared to uninjured controls. Overall mean levels of UCH-L1 in TBI patients was 44.2 ng/mL (±7.9) compared with 2.7 ng/mL (±0.7) in controls (p <.001). There were significantly higher levels of UCH-L1 in patients with a lower GCS score at 24 hrs, in those with postinjury complications, in those with 6-wk mortality, and in those with a poor 6-month dichotomized Glasgow outcome score. Conclusions:These data suggest that this novel biomarker has the potential to determine injury severity in TBI patients. Further studies are needed to validate these findings in a larger sample.


Annals of Emergency Medicine | 2012

Elevated Levels of Serum Glial Fibrillary Acidic Protein Breakdown Products in Mild and Moderate Traumatic Brain Injury Are Associated With Intracranial Lesions and Neurosurgical Intervention

Linda Papa; Lawrence M. Lewis; Jay L. Falk; Zhiqun Zhang; Salvatore Silvestri; Philip Giordano; Gretchen M. Brophy; Jason A. Demery; Neha K. Dixit; Ian Ferguson; Ming Cheng Liu; Jixiang Mo; Linnet Akinyi; Kara Schmid; Stefania Mondello; Claudia S. Robertson; Frank C. Tortella; Ronald L. Hayes; Kevin K. W. Wang

STUDY OBJECTIVE This study examines whether serum levels of glial fibrillary acidic protein breakdown products (GFAP-BDP) are elevated in patients with mild and moderate traumatic brain injury compared with controls and whether they are associated with traumatic intracranial lesions on computed tomography (CT) scan (positive CT result) and with having a neurosurgical intervention. METHODS This prospective cohort study enrolled adult patients presenting to 3 Level I trauma centers after blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale (GCS) score of 9 to 15. Control groups included normal uninjured controls and trauma controls presenting to the emergency department with orthopedic injuries or a motor vehicle crash without traumatic brain injury. Blood samples were obtained in all patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for GFAP-BDP (nanograms/milliliter). RESULTS Of the 307 patients enrolled, 108 were patients with traumatic brain injury (97 with GCS score 13 to 15 and 11 with GCS score 9 to 12) and 199 were controls (176 normal controls and 16 motor vehicle crash controls and 7 orthopedic controls). Receiver operating characteristic curves demonstrated that early GFAP-BDP levels were able to distinguish patients with traumatic brain injury from uninjured controls with an area under the curve of 0.90 (95% confidence interval [CI] 0.86 to 0.94) and differentiated traumatic brain injury with a GCS score of 15 with an area under the curve of 0.88 (95% CI 0.82 to 0.93). Thirty-two patients with traumatic brain injury (30%) had lesions on CT. The area under these curves for discriminating patients with CT lesions versus those without CT lesions was 0.79 (95% CI 0.69 to 0.89). Moreover, the receiver operating characteristic curve for distinguishing neurosurgical intervention from no neurosurgical intervention yielded an area under the curve of 0.87 (95% CI 0.77 to 0.96). CONCLUSION GFAP-BDP is detectable in serum within an hour of injury and is associated with measures of injury severity, including the GCS score, CT lesions, and neurosurgical intervention. Further study is required to validate these findings before clinical application.


Journal of Neurotrauma | 2010

αII-Spectrin Breakdown Products (SBDPs): Diagnosis and Outcome in Severe Traumatic Brain Injury Patients

Stefania Mondello; Steven A. Robicsek; Andrea Gabrielli; Gretchen M. Brophy; Linda Papa; Joseph J. Tepas; Claudia S. Robertson; András Büki; Dancia Scharf; Mo Jixiang; Linnet Akinyi; Uwe Muller; Kevin K. W. Wang; Ronald L. Hayes

In this study we assessed the clinical utility of quantitative assessments of alphaII-spectrin breakdown products (SBDP145 produced by calpain, and SBDP120 produced by caspase-3) in cerebrospinal fluid (CSF) as markers of brain damage and outcome after severe traumatic brain injury (TBI). We analyzed 40 adult patients with severe TBI (Glasgow Coma Scale [GCS] score <or=8) who underwent ventriculostomy. Patients requiring CSF drainage for other medical reasons served as controls. CSF samples were taken at admission and every 6 h thereafter for a maximum of 7 days and assessed using novel quantitative fragment-specific ELISAs for SBDPs. Outcome was assessed using the 3-month Glasgow Outcome Scale. Mean CSF levels of SBDPs were significantly higher in TBI patients than in controls at all time points examined. Different temporal release patterns of CSF SBDP145 and SBDP120 were observed. SBDP145 provided accurate diagnoses at all time points examined, while SBDP120 release was more accurate 24 h after injury. Within 24 h after injury, SBDP145 CSF concentrations significantly correlated with GCS scores, while SBDP120 levels correlated with age. SBDP levels were significantly higher in patients who died than in those who survived. SBDP145 levels (>6 ng/mL) and SBDP120 levels (>17.55 ng/mL) strongly predicted death (odds ratio 5.9 for SBDP145, and 18.34 for SBDP120). The time course of SBDPs in nonsurvivors also differed from that of survivors. These results suggest that CSF SBDP levels can predict injury severity and mortality after severe TBI, and can be useful complements to clinical assessment.


Intensive Care Medicine | 2014

Consensus summary statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care: A statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Peter Le Roux; David K. Menon; Giuseppe Citerio; Paul Vespa; Mary Kay Bader; Gretchen M. Brophy; Michael N. Diringer; Nino Stocchetti; Walter Videtta; Rocco Armonda; Neeraj Badjatia; Julian Böesel; Randall M. Chesnut; Sherry Chou; Jan Claassen; Marek Czosnyka; Michael De Georgia; Anthony A. Figaji; Jennifer E. Fugate; Raimund Helbok; David Horowitz; Peter J. Hutchinson; Monisha A. Kumar; Molly McNett; Chad Miller; Andrew M. Naidech; Mauro Oddo; DaiWai M. Olson; Kristine O'Phelan; J. Javier Provencio

Neurocritical care depends, in part, on careful patient monitoring but as yet there are little data on what processes are the most important to monitor, how these should be monitored, and whether monitoring these processes is cost-effective and impacts outcome. At the same time, bioinformatics is a rapidly emerging field in critical care but as yet there is little agreement or standardization on what information is important and how it should be displayed and analyzed. The Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine, and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to begin to address these needs. International experts from neurosurgery, neurocritical care, neurology, critical care, neuroanesthesiology, nursing, pharmacy, and informatics were recruited on the basis of their research, publication record, and expertise. They undertook a systematic literature review to develop recommendations about specific topics on physiologic processes important to the care of patients with disorders that require neurocritical care. This review does not make recommendations about treatment, imaging, and intraoperative monitoring. A multidisciplinary jury, selected for their expertise in clinical investigation and development of practice guidelines, guided this process. The GRADE system was used to develop recommendations based on literature review, discussion, integrating the literature with the participants’ collective experience, and critical review by an impartial jury. Emphasis was placed on the principle that recommendations should be based on both data quality and on trade-offs and translation into clinical practice. Strong consideration was given to providing pragmatic guidance and recommendations for bedside neuromonitoring, even in the absence of high quality data.


Journal of Trauma-injury Infection and Critical Care | 2012

Serum levels of ubiquitin C-terminal hydrolase distinguish mild traumatic brain injury from trauma controls and are elevated in mild and moderate traumatic brain injury patients with intracranial lesions and neurosurgical intervention.

Linda Papa; Lawrence M. Lewis; Salvatore Silvestri; Jay L. Falk; Philip Giordano; Gretchen M. Brophy; Jason A. Demery; Ming Cheng Liu; Jixiang Mo; Linnet Akinyi; Stefania Mondello; Kara Schmid; Claudia S. Robertson; Frank C. Tortella; Ronald L. Hayes; Kevin K. W. Wang

BACKGROUND: This study compared early serum levels of ubiquitin C-terminal hydrolase (UCH-L1) from patients with mild and moderate traumatic brain injury (TBI) with uninjured and injured controls and examined their association with traumatic intracranial lesions on computed tomography (CT) scan (CT positive) and the need for neurosurgical intervention (NSI). METHODS: This prospective cohort study enrolled adult patients presenting to three tertiary care Level I trauma centers after blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale (GCS) score 9 to 15. Control groups included normal uninjured controls and nonhead injured trauma controls presenting to the emergency department with orthopedic injuries or motor vehicle crash without TBI. Blood samples were obtained in all trauma patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for UCH-L1 (ng/mL ± standard error of the mean). RESULTS: There were 295 patients enrolled, 96 TBI patients (86 with GCS score 13–15 and 10 with GCS score 9–12), and 199 controls (176 uninjured, 16 motor vehicle crash controls, and 7 orthopedic controls). The AUC for distinguishing TBI from uninjured controls was 0.87 (95% confidence interval [CI], 0.82–0.92) and for distinguishing those TBIs with GCS score 15 from controls was AUC 0.87 (95% CI, 0.81–0.93). Mean UCH-L1 levels in patients with CT negative versus CT positive were 0.620 (±0.254) and 1.618 (±0.474), respectively (p < 0.001), and the AUC was 0.73 (95% CI, 0.62–0.84). For patients without and with NSI, levels were 0.627 (0.218) versus 2.568 (0.854; p < 0.001), and the AUC was 0.85 (95% CI, 0.76–0.94). CONCLUSION: UCH-L1 is detectable in serum within an hour of injury and is associated with measures of injury severity including the GCS score, CT lesions, and NSI. Further study is required to validate these findings before clinical application. LEVEL OF EVIDENCE: II, prognostic study.


Journal of Neurotrauma | 2011

Biokinetic Analysis of Ubiquitin C-Terminal Hydrolase-L1 (UCH-L1) in Severe Traumatic Brain Injury Patient Biofluids

Gretchen M. Brophy; Stefania Mondello; Linda Papa; Steven A. Robicsek; Andrea Gabrielli; Joseph J. Tepas; András Büki; Claudia S. Robertson; Frank C. Tortella; Ronald L. Hayes; Kevin K. W. Wang

Ubiquitin C-terminal hydrolase-L1 (UCH-L1) is a neuron-specific enzyme that has been identified as a potential biomarker of traumatic brain injury (TBI). The study objectives were to determine UCH-L1 exposure and kinetic metrics, determine correlations between biofluids, and assess outcome correlations in severe TBI patients. Data were analyzed from a prospective, multicenter study of severe TBI (Glasgow Coma Scale [GCS] score ≤ 8). Cerebrospinal fluid (CSF) and serum data from samples taken every 6 h after injury were analyzed by enzyme-linked immunosorbent assay (ELISA). UCH-L1 CSF and serum data from 59 patients were used to determine biofluid correlations. Serum samples from 86 patients and CSF from 59 patients were used to determine outcome correlations. Exposure and kinetic metrics were evaluated acutely and up to 7 days post-injury and compared to mortality at 3 months. There were significant correlations between UCH-L1 CSF and serum median concentrations (r(s)=0.59, p<0.001), AUC (r(s)=0.3, p=0.027), Tmax (r(s)=0.68, p<0.001), and MRT (r(s)=0.65, p<0.001). Outcome analysis showed significant increases in median serum AUC (2016 versus 265 ng/mL*min, p=0.006), and Cmax (2 versus 0.4 ng/mL, p=0.003), and a shorter Tmax (8 versus 19 h, p=0.04) in those who died versus those who survived, respectively. In the first 24 h after injury, there was a statistically significant acute increase in CSF and serum median Cmax((0-24h)) in those who died. This study shows a significant correlation between UCH-L1 CSF and serum median concentrations and biokinetics in severe TBI patients, and relationships with clinical outcome were detected.


Journal of Neurotrauma | 2009

αII-Spectrin Breakdown Product Cerebrospinal Fluid Exposure Metrics Suggest Differences in Cellular Injury Mechanisms after Severe Traumatic Brain Injury

Gretchen M. Brophy; Jose A. Pineda; Linda Papa; Stephen B. Lewis; Alex B. Valadka; H. Julia Hannay; Shelley C. Heaton; Jason A. Demery; Ming Cheng Liu; Joseph J. Tepas; Andrea Gabrielli; Steven A. Robicsek; Kevin K. W. Wang; Claudia S. Robertson; Ronald L. Hayes

Traumatic brain injury (TBI) produces alphaII-spectrin breakdown products (SBDPs) that are potential biomarkers for TBI. To further understand these biomarkers, the present study examined (1) the exposure and kinetic characteristics of SBDPs in cerebrospinal fluid (CSF) of adults with severe TBI, and (2) the relationship between these exposure and kinetic metrics and severity of injury. This clinical database study analyzed CSF concentrations of 150-, 145-, and 120-kDa SBDPs in 38 severe TBI patients. Area under the curve (AUC), mean residence time (MRT), maximum concentration (C(max)), time to maximum concentration (T(max)), and half-life (t(1/2)) were determined for each SBDP. Markers of calpain proteolysis (SBDP150 and SBDP145) had a greater median AUC and C(max) and a shorter MRT than SBDP120, produced by caspase-3 proteolysis in the CSF in TBI patients ( p < 0.001). AUC and MRT for SBDP150 and SBDP15 were significantly greater in patients with worse Glasgow Coma Scale (GCS) scores at 24 h after injury compared to those whose GCS scores improved (AUC p=0.013, MRT p=0.001; AUC p=0.009, MRT p=0.021, respectively). A positive correlation was found between patients with longer elevations in intracranial pressure (ICP) measurements of 25mmHg or higher and those with a greater AUC and MRT for all three biomarkers. This is the first study to show that the biomarkers of proteolysis differentially associated with calpain and caspase-3 activity have distinct CSF exposure profiles following TBI that suggest a prominent role for calpain activity. Further studies are being conducted to determine if exposure and kinetic metrics for biofluid-based biomarkers can predict clinical outcome.


Journal of Neurotrauma | 2014

GFAP out-performs S100β in detecting traumatic intracranial lesions on computed tomography in trauma patients with mild traumatic brain injury and those with extracranial lesions.

Linda Papa; Salvatore Silvestri; Gretchen M. Brophy; Philip Giordano; Jay L. Falk; Carolina F. Braga; Ciara N. Tan; Neema J. Ameli; Jason A. Demery; Neha K. Dixit; Matthew E. Mendes; Ronald L. Hayes; Kevin K. W. Wang; Claudia S. Robertson

Both glial fibrillary acidic protein (GFAP) and S100β are found in glial cells and are released into serum following a traumatic brain injury (TBI), however, the clinical utility of S100β as a biomarker has been questioned because of its release from bone. This study examined the ability of GFAP and S100β to detect intracranial lesions on computed tomography (CT) in trauma patients and also assessed biomarker performance in patients with fractures and extracranial injuries on head CT. This prospective cohort study enrolled a convenience sample of adult trauma patients at a Level I trauma center with and without mild or moderate traumatic brain injury (MMTBI). Serum samples were obtained within 4 h of injury. The primary outcome was the presence of traumatic intracranial lesions on CT scan. There were 397 general trauma patients enrolled: 209 (53%) had a MMTBI and 188 (47%) had trauma without MMTBI. Of the 262 patients with a head CT, 20 (8%) had intracranial lesions. There were 137 (35%) trauma patients who sustained extracranial fractures below the head to the torso and extremities. Levels of S100β were significantly higher in patients with fractures, compared with those without fractures (p<0.001) whether MMTBI was present or not. However, GFAP levels were not significantly affected by the presence of fractures (p>0.05). The area under the receiver operating characteristics curve (AUC) for predicting intracranial lesions on CT for GFAP was 0.84 (0.73-0.95) and for S100β was 0.78 (0.67-0.89). However, in the presence of extracranial fractures, the AUC for GFAP increased to 0.93 (0.86-1.00) and for S100β decreased to 0.75 (0.61-0.88). In a general trauma population, GFAP out-performed S100β in detecting intracranial CT lesions, particularly in the setting of extracranial fractures.


Journal of Neurotrauma | 2009

Safety and tolerability of cyclosporin a in severe traumatic brain injury patients: results from a prospective randomized trial.

Anna Mazzeo; Gretchen M. Brophy; Charlotte Gilman; Óscar Luís Alves; Jaime R. Robles; Ronald L. Hayes; John T. Povlishock; M. Ross Bullock

Cyclosporin A (CsA) has recently been proposed for use in the early phase after traumatic brain injury (TBI), for its ability to preserve mitochondrial integrity in experimental brain injury models, and thereby provide improved behavioral outcomes as well as significant histological protection. The aim of this prospective, randomized, double-blind, dual-center, placebo-controlled trial was to evaluate the safety, tolerability, and pharmacokinetics of a single intravenous infusion of CsA in patients with severe TBI. Fifty adult severe TBI patients were enrolled over a 22-month period. Within 12 h of the injury patients received 5 mg/kg of CsA infused over 24 h, or placebo. Blood urea nitrogen (BUN), creatinine, hemoglobin, platelets, white blood cell count (WBC), and a hepatic panel were monitored on admission, and at 12, 24, 36, and 48 h, and on days 4 and 7. Potential adverse events (AEs) were also recorded. Neurological outcome was recorded at 3 and 6 months after injury. This study revealed only transient differences in BUN levels at 24 and 48 h and for WBC counts at 24 h between the CsA and placebo patients. These modest differences were not clinically significant in that they did not negatively impact on patient course. Both BUN and creatinine values, markers of renal function, remained within their normal limits over the entire monitoring period. There were no significant differences in other mean laboratory values, or in the incidence of AEs at any other measured time point. Also, no significant difference was demonstrated for neurological outcome. Based on these results, we report a good safety profile of CsA infusion when given at the chosen dose of 5 mg/kg, infused over 24 h, during the early phase after severe head injury in humans, with the aim of neuroprotection.

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Linda Papa

Orlando Regional Medical Center

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Paul Vespa

University of California

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