Review Paper on Penetrating Brain Injury: Ethical Quandaries in the Trauma Bay and Beyond.

OBJECTIVE: The aim of this review was to review the ethical and multidisciplinary clinical challenges facing trauma surgeons when resuscitating patients presenting with penetrating brain injury (PBI) and multicavitary trauma. BACKGROUND: While there is a significant gap in the literature on managing PBI in patients presenting with multisystem trauma, recent data demonstrate that resuscitation and prognostic features for such patients remains poorly described, with trauma guidelines out of date in this field. METHODS: We reviewed a combination of recent multidisciplinary evidence-informed guidelines for PBI and coupled this with expert opinion from trauma, neurosurgery, neurocritical care, pediatric and transplant surgery, surgical ethics and importantly our community partners. RESULTS: Traditional prognostic signs utilized in traumatic brain injury may not be applicable to PBI with a multidisciplinary team approach suggested on a case-by-case basis. Even with no role for neurosurgical intervention, neurocritical care, and neurointerventional support may be warranted, in parallel to multicavitary operative intervention. Special considerations should be afforded for pediatric PBI. Ethical considerations center on providing the patient with the best chance of survival. Consideration of organ donation should be considered as part of the continuum of patient, proxy and family-centric support and care. Community input is crucial in guiding decision making or protocol establishment on an institutional level. CONCLUSIONS: Support of the patient after multicavitary PBI can be complex and is best addressed in a multidisciplinary fashion with extensive community involvement.

Practice Standards for the Use of Multimodality Neuromonitoring: A Delphi Consensus Process.

OBJECTIVES: To address areas in which there is no consensus for the technologies, effort, and training necessary to integrate and interpret information from multimodality neuromonitoring (MNM). DESIGN: A three-round Delphi consensus process. SETTING: Electronic surveys and virtual meeting. SUBJECTS: Participants with broad MNM expertise from adult and pediatric intensive care backgrounds. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two rounds of surveys were completed followed by a virtual meeting to resolve areas without consensus and a final survey to conclude the Delphi process. With 35 participants consensus was achieved on 49% statements concerning MNM. Neurologic impairment and the potential for MNM to guide management were important clinical considerations. Experts reached consensus for the use of MNM-both invasive and noninvasive-for patients in coma with traumatic brain injury, aneurysmal subarachnoid hemorrhage, and intracranial hemorrhage. There was consensus that effort to integrate and interpret MNM requires time independent of daily clinical duties, along with specific skills and expertise. Consensus was reached that training and educational platforms are necessary to develop this expertise and to provide clinical correlation. CONCLUSIONS: We provide expert consensus in the clinical considerations, minimum necessary technologies, implementation, and training/education to provide practice standards for the use of MNM to individualize clinical care.

Novel EEG Metric Correlates with Intracranial Pressure in an Animal Model.

BACKGROUND: Intracranial pressure (ICP) can be continuously and reliably measured using invasive monitoring through an external ventricular catheter or an intraparenchymal probe. We explore electroencephalography (EEG) to identify a reliable real-time noninvasive ICP correlate. METHODS: Using a previously described porcine model of intracranial hypertension, we examined the cross correlation between ICP time series and the slope of the EEG power spectral density as described by ϕ. We calculated ϕ as tan-1 (slope of power spectral density) and normalized it by π, where slope is that of the power-law fit (log frequency vs. log power) to the power spectral density of the EEG signal. Additionally, we explored the relationship between the ϕ time series and cerebral perfusion pressure. A total of 11 intracranial hypertension episodes across three different animals were studied. RESULTS: The mean correlation between ϕ angle and ICP was - 0.85 (0.15); the mean correlation with cerebral perfusion pressure was 0.92 (0.02). Significant correlation occurred at zero lag. In the absence of intracranial hypertension, the absolute value of the ϕ angle was greater than 0.9 (mean 0.936 radians). However, during extreme intracranial hypertension causing cerebral circulatory arrest, the ϕ angle is on average below 0.9 radians (mean 0.855 radians). CONCLUSIONS: EEG ϕ angle is a promising real-time noninvasive measure of ICP/cerebral perfusion using surface electroencephalography.

Managing Severe Traumatic Brain Injury Across Resource Settings: Latin American Perspectives.

Severe traumatic brain injury (sTBI) is a condition of increasing epidemiologic concern worldwide. Outcomes are worse as observed in low- and middle-income countries (LMICs) versus high-income countries. Global targets are in place to address the surgical burden of disease. At the same time, most of the published literature and evidence on the clinical approach to sTBI comes from wealthy areas with an abundance of resources. The available paradigms, including the Brain Trauma Foundation guidelines, the Seattle International Severe Traumatic Brain Injury Consensus Conference, Consensus Revised Imaging and Clinical Examination, and multimodality approaches, may fit differently depending on local resources, expertise, and sociocultural factors. A first step toward addressing heterogeneity in practice is to consider comparative effectiveness approaches that can capture actual practice patterns and record short-term and long-term outcomes of interest. Decompressive craniectomy (DC) decreases intracranial pressure burden and can be lifesaving. Nevertheless, completed randomized controlled trials took place within high-income settings, leaving important questions unanswered and making extrapolations to LMICs questionable. The concept of preemptive DC specifically to address limited neuromonitoring resources may warrant further study to establish a benefit/risk profile for the procedure and its role within local protocols of care.

Machine Learning for Early Detection of Hypoxic-Ischemic Brain Injury After Cardiac Arrest.

BACKGROUND: Establishing whether a patient who survived a cardiac arrest has suffered hypoxic-ischemic brain injury (HIBI) shortly after return of spontaneous circulation (ROSC) can be of paramount importance for informing families and identifying patients who may benefit the most from neuroprotective therapies. We hypothesize that using deep transfer learning on normal-appearing findings on head computed tomography (HCT) scans performed after ROSC would allow us to identify early evidence of HIBI. METHODS: We analyzed 54 adult comatose survivors of cardiac arrest for whom both an initial HCT scan, done early after ROSC, and a follow-up HCT scan were available. The initial HCT scan of each included patient was read as normal by a board-certified neuroradiologist. Deep transfer learning was used to evaluate the initial HCT scan and predict progression of HIBI on the follow-up HCT scan. A naive set of 16 additional patients were used for external validation of the model. RESULTS: The median age (interquartile range) of our cohort was 61 (16) years, and 25 (46%) patients were female. Although findings of all initial HCT scans appeared normal, follow-up HCT scans showed signs of HIBI in 29 (54%) patients (computed tomography progression). Evaluating the first HCT scan with deep transfer learning accurately predicted progression to HIBI. The deep learning score was the most significant predictor of progression (area under the receiver operating characteristic curve = 0.96 [95% confidence interval 0.91-1.00]), with a deep learning score of 0.494 having a sensitivity of 1.00, specificity of 0.88, accuracy of 0.94, and positive predictive value of 0.91. An additional assessment of an independent test set confirmed high performance (area under the receiver operating characteristic curve = 0.90 [95% confidence interval 0.74-1.00]). CONCLUSIONS: Deep transfer learning used to evaluate normal-appearing findings on HCT scans obtained early after ROSC in comatose survivors of cardiac arrest accurately identifies patients who progress to show radiographic evidence of HIBI on follow-up HCT scans.

Frequency, Risk Factors, and Outcomes of Unplanned Readmission to the Neurological Intensive Care Unit after Spontaneous Intracerebral Hemorrhage.

BACKGROUND: Unplanned readmission to the neurological intensive care unit (ICU) is an underinvestigated topic in patients admitted after spontaneous intracerebral hemorrhage (ICH). The purpose of this study is to investigate the frequency, clinical risk factors, and outcome of bounce back to the neurological ICU in a cohort of patients admitted after ICH. METHODS: This is a retrospective observational study inspecting bounce back to the neurological ICU in patients admitted with spontaneous ICH over an 8-year period. For each patient, demographics, medical history, clinical presentation, length of ICU stay, unplanned readmission to neurological ICU, cause of readmission, and mortality were reviewed. Bounce back to the neurological ICU was defined as an unplanned readmission to the neurological ICU from a general floor service during the same hospitalization. A multivariable analysis was used to define independent variables associated with bounce back to the neurological ICU as well as association between bounce back to the neurological ICU and mortality. The significance level was set at p < 0.05. RESULTS: A total of 221 patients were included. Among those, 20 (9%) had a bounce back to the neurological ICU. Respiratory complications (n = 11) was the most common reason for bounce back to the neurological ICU, followed by neurological (n = 5) and cardiological (n = 4) complications. In a multivariable logistic regression, location of hemorrhage in the basal ganglia (odds ratio [OR]: 3.0, 95% confidence interval [CI]: 1.0-8.9, p = 0.03) and dysphagia at the time of transfer (OR: 3.9, 95% CI: 1.0-15.4, p = 0.04) were significantly associated with bounce back to the neurological ICU. After we controlled for ICH score, readmission to the ICU was also independently associated with higher mortality (OR: 14.1, 95% CI: 2.8-71.7, p < 0.01). CONCLUSIONS: Bounce back to the neurological ICU is not an infrequent complication in patients with spontaneous ICH and is associated with higher hospital length of stay and mortality. We identified relevant and potentially modifiable risk factors associated with bounce back to the neurological ICU. Future prospective studies are necessary to develop patient-centered strategies that may improve transition from the neurological ICU to the general floor.

Defining Death Behind the Veil of Ignorance.

In this article I examine the question of how a liberal state should go about defining death. Plausible standards for a definition of death include a somatic one based on circulatory criteria, death by neurologic criteria (DNC), and higher brain death. I will argue that Rawlsian "burdens of judgment" apply in this process: that is, reasonable disagreement should be expected on important topics, and such disagreement ought not be resolved via the coercive powers of the state. Nevertheless, the state must legislate a definition of death, and in doing so faces a "neutralist dilemma," that is, when there are multiple reasonable ways to move forward, only one can be chosen. I will examine a possible way to exit this neutralist dilemma. Finally, I will argue for DNC as the normatively preferred default definition of death. To do this, I will employ the Rawlsian heuristic of the "original position" and offer public reasons in favor of using DNC as the preferred default definition of death.

Civilian Firearm-Inflicted Brain Injury: Coagulopathy, Vascular Injuries, and Triage.

PURPOSE OF REVIEW: Civilian firearm-inflicted penetrating brain injury (PBI) carries high morbidity and mortality. Concurrently, the evidence base guiding management decisions remains limited. Faced with large volume of PBI patients, we have made observations in relation to coagulopathy and cerebrovascular injuries. We here review this literature in addition to the question about early prognostication as it may inform neurosurgical decision-making. RECENT FINDINGS: The triad of coagulopathy, low motor score, and radiographic compression of basal cisterns comprises a phenotype of injury with exceedingly high mortality. PBI leads to high rates of cerebral arterial and venous injuries, and projectile trajectory is emerging as an independent predictor of outcome. The combination of coagulopathy with cerebrovascular injury creates a specific endophenotype. The nature and role of coagulopathy remain to be deciphered, and consideration to the use of tranexamic acid should be given. Prospective controlled trials are needed to create clinical evidence free of patient selection bias.

To Decompress or Not? An Expected Utility Inspired Approach To Shared decision-making For Supratentorial Ischemic Stroke.

Patients with large territorial supratentorial infarctions are at high risk of cerebral edema, increased intracranial pressure, tissue herniation and death. There is strong evidence supporting prompt decompressive craniectomy after large hemispheric ischemic stroke as a means to reduce mortality. Nevertheless, functional outcomes can vary significantly. Clinical trials have traditionally judged these outcomes by a priori dichotomization without taking into account individual patient and caregiver preferences. If these are not incorporated into shared decision-making, there are significant risks in both directions, i.e. producing outcomes that may be judged as unacceptable to survivors, or not offering life-saving treatments to patients that according to their own values could be beneficial. In the absence of decision aids, we explore insights from decision theory and propose an expected utility-inspired approach as a supplementary navigating tool in the decision-making process. Four patient case scenarios are discussed as a demonstration of using individualized rankings of outcome preferences, and deriving expected utilities for interventions such as decompressive craniectomy versus medical therapy. The ultimate aim of the suggested approach is to assure that patient values are elicited and incorporated, and possible range and nature of outcomes are discussed, and by attempting to connect best available means to patient individualized ends.

Early Determinants of Neurocritical Care Unit Length of Stay in Patients with Spontaneous Intracerebral Hemorrhage.

BACKGROUND: The present study considers patients with spontaneous intracerebral hemorrhage (ICH) admitted to the neurocritical care unit (NCCU) through the Emergency Department (ED). It aims to identify patient-specific clinical variables that can be assessed on presentation and that are associated with prolonged NCCU length of stay (LOS). METHODS: A cross-sectional, single-center, retrospective analysis of ICH patients directly admitted from the ED to the NCCU over an 8-year period was performed. Patients' demographics, clinical exam characteristics, serum laboratory values, intubation status, and neurosurgical procedures at presentation were recorded. Head computed tomography scans obtained on presentation were reviewed. LOS was calculated based on the number of midnights spent in the NCCU. Prolonged LOS was determined using a change point analysis, adopting the method of Taylor which utilizes CUMSUM charts and bootstrap analysis. A decision tree model was trained and validated to identify reliable variables associated with prolonged LOS. RESULTS: Two hundred and five patients with ICH were analyzed. Prolonged LOS was calculated to be a stay that exceeds 8 days; 68 patients (33%) had a prolonged LOS in NCCU. Median LOS did not differ between survivors and patients who died in hospital. Clinical variables explored through the decision tree model were intubation status, neurosurgical intervention (EVD, decompression or evacuation within 24 h from presentation), and components of the ICH score: age, GCS, hematoma volume, the presence of intraventricular hemorrhage (IVH), and infratentorial location. The model accuracy was 0.8 and AUC was 0.83 (95% CI 0.78-0.89). CONCLUSION: We propose an ICH-LOS model based on neurosurgical intervention, intubation status and GCS at presentation to predict prolonged LOS in the NCCU in patients with ICH. This simple clinical tool, if prospectively validated, could help with medical planning, contribute to patient care-directed conversations, assist in optimizing hospital resource utilization, and, more importantly, motivating patient-specific interventions aimed at optimizing outcomes and decreasing LOS.

Cerebrovascular Complications in Early Survivors of Civilian Penetrating Brain Injury.

BACKGROUND: This study investigates the presence of cerebrovascular injuries in a large sample of civilian penetrating brain injury (PBI) patients, determining the prevalence, radiographic characteristics, and impact on short-term outcome. METHODS: We retrospectively reviewed patients with PBI admitted to our institution over a 2-year period. Computed tomography head scans, computer tomography angiograms and venograms of the intracranial vessels were evaluated to determine the wound trajectory, intracranial injury characteristics, and presence of arterial (AI) and venous sinus (VSI) injuries. Demographics, clinical presentation, and treatment were also reviewed. Discharge disposition was used as surrogate of short-term outcome. RESULTS: Seventy-two patients were included in the study. The mechanism of injury was gunshot wounds in 71 patients and stab wound in one. Forty-one of the 72 patients (60%) had at least one vascular injury. Twenty-six out of 72 patients suffered an AI (36%), mostly pseudoaneurysms and occlusions, involving the anterior and middle cerebral arteries. Of the 72 patients included, 45 had dedicated computed tomography venograms, and of those 22 had VSI (49%), mainly manifesting as superior sagittal sinus occlusion. In a multivariable regression model, intraventricular hemorrhage at presentation was associated with AI (OR 9.9, p = 0.004). The same was not true for VSI. CONCLUSION: Acute traumatic cerebrovascular injury is a prevalent complication in civilian PBI, frequently involving both the arterial and venous sinus systems. Although some radiographic features might be associated with presence of vascular injury, assessment of the intracranial vasculature in the acute phase of all PBI is essential for early diagnosis. Treatment of vascular injury remains variable depending on local practice.

Temporal Evolution and Outcomes of Non-Traumatic Intracerebral Hemorrhage in Hospitalized Patients.

OBJECTIVE: To investigate the radiographic features, temporal evolution, and outcome of patients who develop non-traumatic intracerebral hemorrhage (ICH) while hospitalized for other causes. METHODS: We retrospectively reviewed consecutive Emergency Department ICH (ED-ICH) and in-hospital ICH (IH-ICH) over an 8-year period. Variables including demographics, medical history, lab values, lead time to diagnosis, defined as time from last known well to first CT scan, and clinical characteristics, follow-up CT scan, as well as the frequency of withdrawal of life support were compared in the two groups. Mortality in correlation with ICH score was assessed. RESULTS: Sixty-One IH-ICH and 216 ED-ICH patients were compared. History of cardiac disease, cancer, coagulopathy and higher SOFA score at time of diagnosis were significantly higher in the IH-ICH group (all P< 0.01). Time from symptom onset to diagnosis was shorter in the IH-ICH group (median 95 versus 117 minutes, P=0.011). Thirty six percent of IH-ICH fell into a worse ICH category when recalculated 6 hours from initial scan time, compared to only 10% of the ED-ICH. ICH score was well calibrated in ED-ICH when assessed both at diagnosis and 6 hours later, but underestimated actual mortality in the IH-ICH, particularly at ICH scores 0 to 3. End of life measures were pursued in 69% of IH-ICH group compared to 19% in the ED-ICH group. CONCLUSIONS: IH-ICH, is associated with higher overall mortality rates and often times heralds withdrawal of life sustaining therapies in patients. In addition, IH-ICH in comparison to ED-ICH, significantly changes in severity metrics within the first 6 hours. ICH score is not accurate and not calibrated to reflect reasonable stratification of mortality in IH-ICH. Prospective validation and investigation of variables accounting for higher IH-ICH mortality are needed.

Inversion of T Waves on Admission is Associated with Mortality in Spontaneous Intracerebral Hemorrhage.

INTRODUCTION: Cardiac dysfunction directly caused by spontaneous intracerebral hemorrhage (ICH) is a poorly understood phenomenon, and its impact on outcome is still uncertain. The aim of this study is to investigate the relationship between electrocardiographic (EKG) abnormalities and mortality in ICH. METHODS: This is a retrospective study analyzing EKG patterns on admission in patients admitted with ICH at a tertiary care center over an eight-year period. For each patient, demographics, medical history, clinical presentation, EKG on admission and during hospitalization, and head CT at presentation were reviewed. Mortality was noted. RESULTS: A total of 301 ICH patients were included in the study. The most prevalent EKG abnormalities were QTc prolongation in 56% of patients (n = 168) followed by inversion of T waves (TWI) in 37% of patients (n = 110). QTc prolongation was associated with ganglionic location (p = 0.03) and intraventricular hemorrhage (IVH) (p = 0.01), TWIs were associated with ganglionic location (p = 0.02), and PR prolongation was associated with IVH (p = 0.01), while QRS prolongation was associated with lobar location (p < 0.01). Volume of ICH, hemispheric laterality, and involvement of insular cortex were not correlated with specific EKG patterns. In a logistic regression model, after correcting for ICH severity and prior cardiac history, presence of TWI was independently associated with mortality (OR: 3.04, CI:1.6-5.8, p < 0.01). Adding TWI to ICH score improved its prognostic accuracy (AUC 0.81, p = 0.04). Disappearance of TWI during hospitalization did not translate into improvement of survival (p = 0.5). CONCLUSION: Presence of TWI on admission is an independent and unmodifiable factor associated with mortality in ICH. Further research is needed to elucidate the pathophysiologic mechanisms underlying electrocardiographic changes after primary intracerebral hemorrhage.

Post-Trial Enhanced Deployment and Technical Performance with the MISTIE Procedure per Lessons Learned.

OBJECTIVE: We hypothesize that procedure deployment rates and technical performance with minimally invasive surgery and thrombolysis for intracerebral hemorrhage (ICH) evacuation (MISTIE) can be enhanced in post-trial clinical practice, per Phase III trial results and lessons learned. MATERIALS AND METHODS: We identified ICH patients and those who underwent MISTIE procedure between 2017-2021 at a single site, after completed enrollments in the Phase III trial. Deployment rates, complications and technical outcomes were compared to those observed in the trial. Initial and final hematoma volume were compared between site measurements using ABC/2, MISTIE trial reading center utilizing manual segmentation, and a novel Artificial Intelligence (AI) based volume assessment. RESULTS: Nineteen of 286 patients were eligible for MISTIE. All 19 received the procedure (6.6% enrollment to screening rate 6.6% compared to 1.6% at our center in the trial; p=0.0018). Sixteen patients (84%) achieved evaculation target < 15 mL residual ICH or > 70% removal, compared to 59.7% in the trial surgical cohort (p=0.034). No poor catheter placement occurred and no surgical protocol deviations. Limitations of ICH volume assessments using the ABC/2 method were shown, while AI based methodology of ICH volume assessments had excellent correlation with manual segmentation by experienced reading centers. CONCLUSIONS: Greater procedure deployment and higher technical success rates can be achieved in post-trial clinical practice than in the MISTIE III trial. AI based measurements can be deployed to enhance clinician estimated ICH volume. Clinical outcome implications of this enhanced technical performance cannot be surmised, and will need assessment in future trials.

Defining Death: Reasonableness and Legitimacy.

The recently published World Brain Death Project aims in alleviating inconsistencies in clinical guidelines and practice in the determination of death by neurologic criteria. However, critics have taken issue with a number of epistemic and metaphysical assertions that critics argue are either false, ad hoc, or confused. In this commentary, I discuss the nature of a definition of death; the plausibility of neurologic criteria as a sensible social, medical, and legal policy; and within a Rawlsian liberal framework, reasons for personal choice or accommodation among neurologic and circulatory definitions. Declaration of human death cannot rest on contested metaphysics or unmeasurable standards, instead it should be regarded as a plausible and widely accepted social construct that conforms to best available and pragmatic medical science and practice. The definition(s) and criteria should be transparent, publicly justifiable, and potentially allow for the accommodation of reasonable choice. This is an approach that situates the definition of death as a political matter. The approach anticipates that no conceptualization of death can claim universal validity, since this is a question that cannot be settled solely on biologic or scientific grounds, rather it is a matter of normative preference, socially constructed and historically contingent.

Withdrawal of Life-Sustaining Treatments in Perceived Devastating Brain Injury: The Key Role of Uncertainty.

BACKGROUND: Withdrawal of life-sustaining treatment (WOLST) is the leading proximate cause of death in patients with perceived devastating brain injury (PDBI). There are reasons to believe that a potentially significant proportion of WOLST decisions, in this setting, are premature and guided by a number of assumptions that falsely confer a sense of certainty. METHOD: This manuscript proposes that these assumptions face serious challenges, and that we should replace unwarranted certainty with an appreciation for the great degree of multi-dimensional uncertainty involved. The article proceeds by offering a taxonomy of uncertainty in PDBI and explores the key role that uncertainty as a cognitive state, may play into how WOLST decisions are reached. CONCLUSION: In order to properly share decision-making with families and surrogates of patients with PDBI, we will have to acknowledge, understand, and be able to communicate the great degree of uncertainty involved.