John S. Garrett M.D.

Hanley, D., L. S. Prichep, N. Badjatia, J. Bazarian, R. Chiacchierini, K. C. Curley, J. Garrett, E. Jones, R. Naunheim, B. O’Neil, J. O’Neill, D. W. Wright and J. S. Huff (2017). “A brain electrical activity (eeg)-based biomarker of functional impairment in traumatic brain injury: A multi-site validation trial.” J Neurotrauma: 2017 Sep [Epub ahead of print].

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The potential clinical utility of a novel quantitative electroencephalographic (EEG)-based Brain Function Index (BFI) as a measure of the presence and severity of functional brain injury was studied as part of an independent prospective validation trial. The BFI was derived using quantitative EEG (QEEG) features associated with functional brain impairment reflecting current consensus on the physiology of concussive injury. Seven hundred and twenty adult patients (18-85 years of age) evaluated within 72 h of sustaining a closed head injury were enrolled at 11 U.S. emergency departments (EDs). Glasgow Coma Scale (GCS) score was 15 in 97%. Standard clinical evaluations were conducted and 5 to 10 min of EEG acquired from frontal locations. Clinical utility of the BFI was assessed for raw scores and percentile values. A multinomial logistic regression analysis demonstrated that the odds ratios (computed against controls) of the mild and moderate functionally impaired groups were significantly different from the odds ratio of the computed tomography (CT) postive (CT+, structural injury visible on CT) group (p = 0.0009 and p = 0.0026, respectively). However, no significant differences were observed between the odds ratios of the mild and moderately functionally impaired groups. Analysis of variance (ANOVA) demonstrated significant differences in BFI among normal (16.8%), mild TBI (mTBI)/concussed with mild or moderate functional impairment, (61.3%), and CT+ (21.9%) patients (p < 0.0001). Regression slopes of the odds ratios for likelihood of group membership suggest a relationship between the BFI and severity of impairment. Findings support the BFI as a quantitative marker of brain function impairment, which scaled with severity of functional impairment in mTBI patients. When integrated into the clinical assessment, the BFI has the potential to aid in early diagnosis and thereby potential to impact the sequelae of TBI by providing an objective marker that is available at the point of care, hand-held, non-invasive, and rapid to obtain.

Hanley, D., L. S. Prichep, N. Badjatia, J. Bazarian, R. P. Chiacchierini, K. C. Curley, J. S. Garrett, E. B. Jones, R. Naunheim, B. J. O’Neil, J. O’Neill, W. David and J. S. Huff (2017). “A brain electrical activity (eeg) based biomarker of functional impairment in traumatic head injury: A multisite validation trial.” J Neurotrauma: 2017 Jun [Epub ahead of print].

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The potential clinical utility of a novel quantitative EEG-based Brain Function Index (BFI) as a measure of the presence and severity of functional brain injury was studied as part of an independent prospective validation trial. The BFI was derived using EEG features associated with functional brain impairment reflecting current consensus on the physiology of concussive injury. 720 adult patients (18-85 years) evaluated within 72 hours of sustaining a closed head injury were enrolled at 11 US Emergency Departments. Glasgow Coma Scale was 15 in 97%. Standard clinical evaluations were conducted and 5-10 minutes of EEG acquired from frontal locations. Clinical utility of the BFI was assessed for raw scores and percentile values. A multinomial logistic regression analysis demonstrated that both the odds ratio of mild functionally impaired group compared to uninjured as well as the odds ratio of the moderate functionally impaired group compared to uninjured, were significantly different from the CT+ (structural injury visible on CT) TBI group (p=0.0009 and p=0.0026, respectively). However, no significance differences in odds (ratios compared to uninjured) of the mild and moderately functionally impaired groups were obtained. ANOVAs demonstrated significant differences in BFI among normal (16.8%), mTBI/concussed (61.3%), and CT+ (21.9%) patients (p<0.0001). Regression slopes of the odds ratios for likelihood of group membership suggest a relationship between the BFI and severity of impairment. Findings support the BFI as a quantitative marker of brain function impairment, which scaled with severity of functional impairment in mTBI patients. When integrated into the clinical assessment, the BFI has the potential to aid in the early diagnosis and thereby potential to impact the sequelae of TBI by providing an objective marker available at the point of care, hand-held, non-invasive and rapid to obtain.

Roden-Foreman, J. W., M. M. Bennett, E. E. Rainey, J. S. Garrett, M. B. Powers and A. M. Warren (2017). “Secondary traumatic stress in emergency medicine clinicians.” Cogn Behav Ther: 1-11.

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Previously called Secondary Traumatic Stress (STS), secondary exposure to trauma is now considered a valid DSM-5 Criterion A stressor for posttraumatic stress disorder (PTSD). Previous studies have found high rates of STS in clinicians who treat traumatically injured patients. However, little research has examined STS among Emergency Medicine (EM) physicians and advanced practice providers (APPs). The current study enrolled EM providers (N = 118) working in one of 10 hospitals to examine risk factors, protective factors, and the prevalence of STS in this understudied population. Most of the participants were physicians (72.9%), Caucasian (85.6%), and male (70.3%) with mean age of 39.7 (SD = 8.9). Overall, 12.7% of the sample screened positive for STS with clinical levels of intrusion, arousal, and avoidance symptom clusters, and 33.9% had at least one symptom cluster at clinical levels. Low resilience and a history of personal trauma were positively associated with positive STS screens and STS severity scores. Borderline significance suggested that female gender and spending >/=10% of one’s time with trauma patients could be additional risk factors. Findings suggest that resilience-building interventions may be beneficial.

Hanley, D., L. S. Prichep, J. Bazarian, J. S. Huff, R. Naunheim, J. Garrett, E. Jones, D. Wright, J. O’Neill, N. Badjatia, D. Gandhi, K. C. Curley, R. Chiacchierini, B. O’Neil and D. C. Hack (2017). “Emergency department triage of traumatic head injury using brain electrical activity biomarkers: A multisite prospective observational validation trial.” Acad Emerg Med: 2017 Feb [Epub ahead of print].

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OBJECTIVES: A brain electrical activity biomarker for identifying traumatic brain injury (TBI) in Emergency Department (ED) patients presenting with high GCS after sustaining a head injury has shown promise for objective, rapid, triage. The main objective of this study was to prospectively evaluate the efficacy of an automated classification algorithm to determine the likelihood of being CT positive, in high functioning TBI patients in the acute state. METHODS: Adult patients admitted to the ED for evaluation within 72 hours of sustaining a closed head injury with GCS 12-15were candidates for study. 720 patients (18-85 years) meeting inclusion/exclusion criteria were enrolled in this observational, prospective validation trial, at 11 US Emergency Departments. Glasgow Coma Scale was 15 in 97%, with the first and third quartile being 15 (IQR=0) in the study population at the time of the evaluation. Standard clinical evaluations were conducted and 5-10 minutes of EEG was acquired from frontal and frontal-temporal scalp locations. Using an a priori derived EEG based classification algorithm developed on an independent population and applied to this validation population prospectively, the likelihood of each subject being CT+ was determined, and performance metrics were computed relative to adjudicated CT findings. RESULTS: Sensitivity of the binary classifier (CT+ or CT-) was 92.3% (87.8%, 95.5%) for detection of any intracranial injury visible on CT (CT+), with specificity of 51.6% (48.1%, 55.1%) and negative predictive value of 96.0% (93.2%, 97.9%). Using ternary classification (CT+, Equivocal, CT-) demonstrated enhanced sensitivity to traumatic hematomas (>/=1cc of blood), 98.6% (92.6%, 100.0%) and negative predictive value of 98.2% (95.5%, 99.5%). CONCLUSIONS: Using an EEG-based biomarker high accuracy of predicting the likelihood of being CT+ was obtained, with high NPV and sensitivity to any traumatic bleeding and to hematomas. Specificity was significantly higher than standard CT decision rules. The short time to acquire results and the ease of use in the ED environment suggests that EEG based classifier algorithms have potential to impact triage and clinical management of head injured patients.