Head-injured patients who talk and deteriorate into coma. Analysis of 211 cases studied with computerized tomography

A machine learning model to predict neurological deterioration after mild traumatic brain injury in older adults

Objective

Neurological deterioration after mild traumatic brain injury (TBI) has been recognized as a poor prognostic factor. Early detection of neurological deterioration would allow appropriate monitoring and timely therapeutic interventions to improve patient outcomes. In this study, we developed a machine learning model to predict the occurrence of neurological deterioration after mild TBI using information obtained on admission.

Methods

This was a retrospective cohort study of data from the Think FAST registry, a multicenter prospective observational study of elderly TBI patients in Japan. Patients with an admission Glasgow Coma Scale (GCS) score of 12 or below or who underwent surgical treatment immediately upon admission were excluded. Neurological deterioration was defined as a decrease of 2 or more points from a GCS score of 13 or more within 24 h of hospital admission. The model predictive accuracy was judged with the area under the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC), and the Youden index was used to determine the cutoff value.

Results

A total of 421 of 721 patients registered in the Think FAST registry between December 2019 and May 2021 were included in our study, among whom 25 demonstrated neurological deterioration. Among several machine learning algorithms, eXtreme Gradient Boosting (XGBoost) demonstrated the highest predictive accuracy in cross-validation, with an AUROC of 0.81 (±0.07) and an AUPRC of 0.33 (±0.08). Through SHapley Additive exPlanations (SHAP) analysis, five important features (D-dimer, fibrinogen, acute subdural hematoma thickness, cerebral contusion size, and systolic blood pressure) were identified and used to construct a better performing model (cross-validation AUROC of 0.84 and AUPRC of 0.34; testing data AUROC of 0.77 and AUPRC of 0.19). At the cutoff value from the Youden index, the model showed a sensitivity, specificity, and positive predictive value of 60, 96, and 38%, respectively. When neurosurgeons attempted to predict neurological deterioration using the same testing data, their values were 20, 94, and 19%, respectively.

Conclusion

In this study, our predictive model showed an acceptable performance in detecting neurological deterioration after mild TBI. Further validation through prospective studies is necessary to confirm these results.

Forensic Pathologist Testimony, Part 1: Common Questions and Considerations

Introduction

Forensic pathologists are the only medical specialists who routinely testify in courts of law as part of their occupation. As such, one element of their training involves learning how to testify responsibly and competently. Individuals qualified as experts are permitted to offer opinions in order to assist the triers of fact.

Results

We review the forensic pathologist's primary role as an expert witness which is to lay out concepts clearly, methodically, and objectively, in medicine, pathophysiology, toxicology, and injury, to convey these concepts with understandable, plain language, and to explain how certain evidence, physical, medical, and historical, supports their conclusions and/or presents limitations.

Discussion

We discuss various components about testifying in court, some common expert questions posed to the forensic pathologist, and what concepts and facts they might consider when answering them. We do not offer a prescription as to how one should answer these questions specifically, but rather we provide a single resource that summarizes some of the key issues that may arise in court for the forensic pathologist.

Usefulness of the Simple Coma Scale, a Simplified Version of the Glasgow Coma Scale

The Glasgow Coma Scale (GCS) is the most commonly used consciousness rating scale worldwide. Although it is a sensitive and accurate way of assessing a patient's level of consciousness, it is time-consuming and requires training. We designed the Simple Coma Scale (SCS) as a simplified version of the GCS. In this study, we examined whether the SCS could predict favorable neurogenic outcomes at discharge, survival, and GCS scores in patients with traumatic brain injury (TBI). We analyzed the data of 1,230 patients registered in the Japan Neurotrauma Data Bank (Project 2015) between April 2015 and March 2017. In the SCS, eye, verbal, and motor scores are given based on a 3-point scoring system, with similar wording ("Normal," "Something Wrong," and "None") used for all scores. The SCS is based on a 7-point scale. The Glasgow Outcome Scale was used to assess the outcomes. For the receiver operating characteristic (ROC) curves with the objective variable of good prognosis at discharge in the SCS and GCS, the area under the curve (AUC) for the SCS was 0.740 (95% confidence interval [CI]: 0.711-0.769), and that of the GCS was 0.757 (95% CI: 0.729-0.786). For ROC curves with survival as the objective variable, the AUC of the SCS was 0.751 (95% CI: 0.724-0.778), and that of the GCS was 0.764 (95% CI: 0.737-0.791). The SCS, similar to the GCS, may predict good prognosis and survival at discharge. Further analyses will continue to examine the usefulness and practicality of the SCS.

Moderate Traumatic Brain Injury in Adult Population: The Latin American Brain Injury Consortium Consensus for Definition and Categorization

Moderate traumatic brain injury (TBI) is a diagnosis that describes diverse patients with heterogeneity of primary injuries. Defined by a Glasgow Coma Scale between 9 and 12, this category includes patients who may neurologically worsen and require increasing intensive care resources and/or emergency neurosurgery. Despite the unique characteristics of these patients, there have not been specific guidelines published before this effort to support decision-making in these patients. A Delphi consensus group from the Latin American Brain Injury Consortium was established to generate recommendations related to the definition and categorization of moderate TBI. Before an in-person meeting, a systematic review of the literature was performed identifying evidence relevant to planned topics. Blinded voting assessed support for each recommendation. A priori the threshold for consensus was set at 80% agreement. Nine PICOT questions were generated by the panel, including definition, categorization, grouping, and diagnosis of moderate TBI. Here, we report the results of our work including relevant consensus statements and discussion for each question. Moderate TBI is an entity for which there is little published evidence available supporting definition, diagnosis, and management. Recommendations based on experts' opinion were informed by available evidence and aim to refine the definition and categorization of moderate TBI. Further studies evaluating the impact of these recommendations will be required.

The unmet global burden of cranial epidural hematomas: A systematic review and meta-analysis

OBJECTIVE

Approximately 69 million people suffer from traumatic brain injury (TBI) annually. Patients with isolated epidural hematomas (EDH) with access to timely surgical intervention often sustain favorable outcomes. Efforts to ensure safe, timely, and affordable access to EDH treatment may offer tremendous benefits.

METHODS

A comprehensive literature search was conducted. A random-effects model was used to pool the outcomes. Studies were further categorized into groups by World Bank Income classification: high-income countries (HICs) and low- and middle-income countries (LMICs).

RESULTS

Forty-nine studies were included, including 36 from HICs, 12 from LMICs, and 1 from HIC / LMIC. Incidence of EDH amongst TBI patients 8.2 % (95 % CI: 5.9,11.2), including 9.2 % (95 %CI 6.4,13.2) in HICs and 5.8 % (95 % CI: 3.1,10.7) in LMICs (p = 0.20). The overall percent male was 73.7 % and 47.4 % were caused by road traffic accidents. Operative rate was 76.0 % (95 %CI: 67.9,82.6), with a numerically lower rate of 74.2 % (95 %CI: 64.0,81.8) in HICs than in LMICs 82.9 % (95 %CI: 65.4,92.5) (p = 0.33). This decreased to 55.5 % after adjustment for small study effect. The non-operative mortality (5.3 %, 95 %CI: 2.2,12.3) was lower than the operative mortality (8.3 %, 95 %CI: 4.6,14.6), with slightly higher rates in HICs than LMICs. This relationship remained after adjustment for small study effect, with 9.3 % operative mortality compared to 6.9 % non-operative mortality.

CONCLUSION

With an overall EDH incidence of 8.2 % and an operative rate of 55.5 %, 3.1 million people worldwide require surgery for traumatic EDH every year, most of whom are in prime working age. Given the favorable prognosis with treatment, traumatic EDH is a strong investment for neurosurgical capacity building.

A Prehospital Triage System to Detect Traumatic Intracranial Hemorrhage Using Machine Learning Algorithms

IMPORTANCE

An adequate system for triaging patients with head trauma in prehospital settings and choosing optimal medical institutions is essential for improving the prognosis of these patients. To our knowledge, there has been no established way to stratify these patients based on their head trauma severity that can be used by ambulance crews at an injury site.

OBJECTIVES

To develop a prehospital triage system to stratify patients with head trauma according to trauma severity by using several machine learning techniques and to evaluate the predictive accuracy of these techniques.

DESIGN, SETTING, AND PARTICIPANTS

This single-center retrospective cohort study was conducted by reviewing the electronic medical records of consecutive patients who were transported to Tokyo Medical and Dental University Hospital in Japan from April 1, 2018, to March 31, 2021. Patients younger than 16 years with cardiopulmonary arrest on arrival or with a significant amount of missing data were excluded.

MAIN OUTCOMES AND MEASURES

Machine learning-based prediction models to detect the presence of traumatic intracranial hemorrhage were constructed. The predictive accuracy of the models was evaluated with the area under the receiver operating curve (ROC-AUC), area under the precision recall curve (PR-AUC), sensitivity, specificity, and other representative statistics.

RESULTS

A total of 2123 patients (1527 male patients [71.9%]; mean [SD] age, 57.6 [19.8] years) with head trauma were enrolled in this study. Traumatic intracranial hemorrhage was detected in 258 patients (12.2%). Among several machine learning algorithms, extreme gradient boosting (XGBoost) achieved the mean (SD) highest ROC-AUC (0.78 [0.02]) and PR-AUC (0.46 [0.01]) in cross-validation studies. In the testing set, the ROC-AUC was 0.80, the sensitivity was 74.0% (95% CI, 59.7%-85.4%), and the specificity was 74.9% (95% CI, 70.2%-79.3%). The prediction model using the National Institute for Health and Care Excellence (NICE) guidelines, which was calculated after consultation with physicians, had a sensitivity of 72.0% (95% CI, 57.5%-83.8%) and a specificity of 73.3% (95% CI, 68.7%-77.7%). The McNemar test revealed no statistically significant differences between the XGBoost algorithm and the NICE guidelines for sensitivity or specificity (P = .80 and P = .55, respectively).

CONCLUSIONS AND RELEVANCE

In this cohort study, the prediction model achieved a comparatively accurate performance in detecting traumatic intracranial hemorrhage using only the simple pretransportation information from the patient. Further validation with a prospective multicenter data set is needed.

Coagulopathy and Traumatic Brain Injury: Overview of New Diagnostic and Therapeutic Strategies

Coagulopathy is a common sequela of traumatic brain injury. Consumptive coagulopathy and secondary hyperfibrinolysis are associated with hypercoagulability. In addition, fibrinolytic pathways are hyperactivated as a result of vascular endothelial cell damage in the injured brain. Coagulation and fibrinolytic parameters change dynamically to reflect these pathologies. Fibrinogen is consumed and degraded after injury, with fibrinogen concentrations at their lowest 3-6 h after injury. Hypercoagulability causes increased fibrinolytic activity, and plasma levels of D-dimer increase immediately after traumatic brain injury, reaching a maximum at 3 h. Owing to disseminated intravascular coagulation in the presence of fibrinolysis, the bleeding tendency is highest within the first 3 h after injury, and often a condition called “talk and deteriorate” occurs. In neurointensive care, it is necessary to measure coagulation and fibrinolytic parameters such as fibrinogen and D-dimer routinely to predict and prevent the development of coagulopathy and its negative outcomes. Currently, the only evidence-based treatment for traumatic brain injury with coagulopathy is tranexamic acid in the subset of patients with mild-to-moderate traumatic brain injury. Coagulation and fibrinolytic parameters should be closely monitored, and treatment should be considered on a patient-by-patient basis.

Final outcome trends in severe traumatic brain injury: a 25-year analysis of single center data

BACKGROUND

Evidence from the last 25 years indicates a modest reduction of mortality after severe traumatic head injury (sTBI). This study evaluates the variation over time of the whole Glasgow Outcome Scale (GOS) throughout those years.

METHODS

The study is an observational cohort study of adults (≥ 15 years old) with closed sTBI (GCS ≤ 8) who were admitted within 48 h after injury. The final outcome was the 1-year GOS, which was divided as follows: (1) dead/vegetative, (2) severely disabled (dependent patients), and (3) good/moderate recovery (independent patients). Patients were treated uniformly according to international protocols in a dedicated ICU. We considered patient characteristics that were previously identified as important predictors and could be determined easily and reliably. The admission years were divided into three intervals (1987-1995, 1996-2004, and 2005-2012), and the following individual CT characteristics were noted: the presence of traumatic subarachnoid or intraventricular hemorrhage (tSAH, IVH), midline shift, cisternal status, and the volume of mass lesions (A × B × C/2). Ordinal logistic regression was performed to estimate associations between predictors and outcomes. The patients' estimated propensity scores were included as an independent variable in the ordinal logistic regression model (TWANG R package).

FINDINGS

The variables associated with the outcome were age, pupils, motor score, deterioration, shock, hypoxia, cistern status, IVH, tSAH, and epidural volume. When adjusting for those variables and the propensity score, we found a reduction in mortality from 55% (1987-1995) to 38% (2005-2012), but we discovered an increase in dependent patients from 10 to 21% and just a modest increase in independent patients of 6%.

CONCLUSIONS

This study covers 25 years of management of sTBI in a single neurosurgical center. The prognostic factors are similar to those in the literature. The improvement in mortality does not translate to better quality of life.

Brain Midline Shift Measurement and Its Automation: A Review of Techniques and Algorithms

Midline shift (MLS) of the brain is an important feature that can be measured using various imaging modalities including X-ray, ultrasound, computed tomography, and magnetic resonance imaging. Shift of midline intracranial structures helps diagnosing intracranial lesions, especially traumatic brain injury, stroke, brain tumor, and abscess. Being a sign of increased intracranial pressure, MLS is also an indicator of reduced brain perfusion caused by an intracranial mass or mass effect. We review studies that used the MLS to predict outcomes of patients with intracranial mass. In some studies, the MLS was also correlated to clinical features. Automated MLS measurement algorithms have significant potentials for assisting human experts in evaluating brain images. In symmetry-based algorithms, the deformed midline is detected and its distance from the ideal midline taken as the MLS. In landmark-based ones, MLS was measured following identification of specific anatomical landmarks. To validate these algorithms, measurements using these algorithms were compared to MLS measurements made by human experts. In addition to measuring the MLS on a given imaging study, there were newer applications of MLS that included comparing multiple MLS measurement before and after treatment and developing additional features to indicate mass effect. Suggestions for future research are provided.

Symptomatic Acute-on-Chronic Subdural Hematoma: A Clinicopathological Study

The pathophysiology of acute-on-chronic subdural hematoma (ACSDH) is complex and incompletely understood. Evidence to date indicates that the overall process is initiated by rotational force with movement of the brain inside the skull, which exerts tensile strain and rupture of bridging veins, leading in turn to acute hemorrhage in the subdural potential space. This is followed by the proliferation of mesenchymal elements with angiogenesis and inflammation, which in turn becomes a substrate for repeated hemorrhage and expansion of the lesion. Given the prevalence of traumatic subdural processes in the forensic setting and the importance of proper assessment of timing, etiology, risk factors, and clinicopathological correlation, we studied 47 patients presenting to the University of Maryland Shock Trauma Center, all of whom underwent craniotomy with resection of the outer membrane due to symptomatic ACSDH. The surgically resected tissue was examined for histopathologic features in all cases. Our findings highlight that ACSDH is a condition precipitated by trauma that affects middle-aged and older adults, is relatively indolent, is unilateral or asymmetric, and has a low in-hospital mortality rate. Pathological analysis demonstrates a substantial outer membrane in all cases with varying degrees of inflammation and organization that cannot be precisely dated as a function of clinical presentation. The extrapolation of adult ACSDH to mixed acute and chronic subdural hemorrhage in the pediatric setting is problematic due to substantial differences in clinical presentation, severity of underlying brain injury, gross and microscopic findings, and outcome.

Clinical Characteristics and Outcome in Elderly Patients with Traumatic Brain Injury: For Establishment of Management Strategy

In recent years, instances of neurotrauma in the elderly have been increasing. This article addresses the clinical characteristics, management strategy, and outcome in elderly patients with traumatic brain injury (TBI). Falls to the ground either from standing or from heights are the most common causes of TBI in the elderly, since both motor and physiological functions are degraded in the elderly. Subdural, contusional and intracerebral hematomas are more common in the elderly than the young as the acute traumatic intracranial lesion. High frequency of those lesions has been proposed to be associated with increased volume of the subdural space resulting from the atrophy of the brain in the elderly. The delayed aggravation of intracranial hematomas has been also explained by such anatomical and physiological changes present in the elderly. Delayed hyperemia/hyperperfusion may also be a characteristic of the elderly TBI, although its mechanisms are not fully understood. In addition, widely used pre-injury anticoagulant and antiplatelet therapies may be associated with delayed aggravation, making the management difficult for elderly TBI. It is an urgent issue to establish preventions and treatments for elderly TBI, since its outcome has been remained poor for more than 40 years.

Delayed Acute Subdural Hematoma Associated With Percutaneous Coronary Intervention

BACKGROUND

Delayed acute subdural hematoma (DASH) is a subdural hematoma which is detected later. An initial computed tomography (CT) does not reveal any intracranial hemorrhage at all. Few patients of DASH after mild traumatic brain injury associated with percutaneous coronary intervention (PCI) have been published.

PATIENT PRESENTATION

A 63-year-old woman presented with cardiac pulmonary arrest due to acute myocardial infarction and lethal arrhythmia. She had hit her head on the road. The initial CT did not reveal any hemorrhage in the intra-cranium. She fully recovered after PCI. However, 1 hour after PCI, she lost consciousness and immediate CT showed acute subdural hematoma and subarachnoid hemorrhage. The period from losing consciousness to brain herniation presenting as anisocoria was very short-only 30 minutes in our patient. Although emergent evacuation of hematoma and external decompression were performed, the patient died 1 day after the operation.

CONCLUSION

The authors encountered a patient of DASH after PCI that resulted in death. Clinicians should be aware that subdural hemorrhage can occur after PCI if no hemorrhage is noted in the initial head CT, and the operation should be performed as soon as possible when the consciousness level decreases.

Measurement of Bone Flap Surface Area and Midline Shift to Predict Overall Survival After Decompressive Craniectomy

BACKGROUND

There is uncertainty about the optimal method for measuring the decompressive craniectomy (DC) surface area and how large the DC should be.

METHODS

A radiological technique for measuring the surface area of removed bone flaps in a series of 73 DCs was developed. Preoperative and early postoperative computed tomography scans of each patient were evaluated. Midline shift (MLS) was considered the key factor for successful DC and was assigned to either normal (0-4 mm) or pathological (≥5 mm) ranges. The association between postoperative MLS and patient survival at 12 months was assessed.

RESULTS

Measurements of all removed bone flaps yielded a mean surface area of 7759 mm². The surface area of the removed bone flap did not influence survival (surviving 7643 mm² vs. deceased 7372 mm²). The only factor associated with survival was reduced postoperative MLS (P < 0.034). Risk of death was 14.4 (3.0-70.1)-fold greater in patients with postoperative shift ≥5 mm (P < 0.001).

CONCLUSION

The ideal surface area for "large" square bone flaps should result in an MLS of <5 mm. Enlargement of the craniectomy edges should be considered for patients in whom MLS ≥5 mm persists according to early postoperative computed tomography scans.

A tale of two acute extradural hematomas

Background:

In much of the Western hemisphere, mortality from traumatic acute extradural hematomas (AEDH) has been drastically brought down toward 0%. This is still not the case however in most developing countries.

Case Description:

This report represents a tragi-comic tale of two cases of traumatic AEDH managed by an academic neurosurgeon in a neurosurgically ill-resourced private health facility during a nationwide industrial strike action preventing clinical-surgical care in the principal author's University Teaching Hospital. A young man presented with altered consciousness, Glasgow Coma Score (GCS) 14/15, following a road accident. The cranial computed tomography (CT) scan was obtained only 9 h after its request, long after the man had actually deteriorated to GCS 7/15 with pupillary changes. The neurosurgeon, summoned from the nearby University Teaching Hospital for the operative care of this man, arrived on-site and was about moving the patient into the operative room when he took the final breaths and died, all within 2 h of the belated neuroimaging. This scenario repeated itself in the same health facility just 24 h later with another young man who presented GCS 7/15 and another identical CT evidence of traumatic AEDH. With more financially able relations, the diagnostic/surgical care of this second patient was much more prompt. He made a very brisk recovery from neurosurgical operative intervention. He is alive and well, 5-month postoperative.

Conclusions:

In most low-resourced health systems of the developing countries, a significant proportion of potentially salvageable cases of AEDH still perish from this disease condition.

Time Course of Coagulation and Fibrinolytic Parameters in Patients with Traumatic Brain Injury

Traumatic brain injury (TBI) has long been associated with coagulopathy; however, the time course of coagulation/fibrinolytic parameters in the acute phase of TBI remains unclear. The purpose of the study was to analyze the time course of coagulation/fibrinolytic parameters in the acute phase of TBI and to elucidate parameter relationships to prognosis. We retrospectively evaluated 234 patients with severe isolated TBI with initial blood samples obtained no more than 1 h after injury. Platelet count, prothrombin time, activated partial thromboplastin time (aPTT), plasma levels of fibrinogen, and D-dimer were measured on arrival in the emergency department and 3, 6, and 12 h after injury. Multivariate logistic regression analysis was performed to identify risk factors for poor prognosis at each time point. From hospital admission to 12 h after injury, an elevated D-dimer level was a significant negative prognostic indicator (admission: p < 0.0001; 3 h after injury: p = 0.0005; 6 h after injury: p = 0.005; 12 h after injury: p = 0.0009). An upward trend of aPTT on admission and 3 h after injury was also a significant negative prognostic indicator (admission: p = 0.0011; 3 h after injury: p = 0.013). On multivariate logistic regression analysis, which included all initial variables, independent risk factors for poor prognosis included older age (p = 0.0005), low Glasgow Coma Scale score (p < 0.0001), high Abbreviated Injury Score (p = 0.015), aPTT >30.2 sec (p = 0.019), and elevated D-dimer level (p = 0.0005). We concluded that D-dimer is the best coagulation/fibrinolytic parameter to monitor for prediction of outcome.

Neuroanatomical predictors of awakening in acutely comatose patients

OBJECTIVE

Lateral brain displacement has been associated with loss of consciousness and poor outcome in a range of acute neurologic disorders. We studied the association between lateral brain displacement and awakening from acute coma.

METHODS

This prospective observational study included all new onset coma patients admitted to the Neurosciences Critical Care Unit (NCCU) over 12 consecutive months. Head computed tomography (CT) scans were analyzed independently at coma onset, after awakening, and at follow-up. Primary outcome measure was awakening, defined as the ability to follow commands before hospital discharge. Secondary outcome measures were discharge Glasgow Coma Scale (GCS), modified Rankin Scale, Glasgow Outcome Scale, and hospital and NCCU lengths of stay.

RESULTS

Of the 85 patients studied, the mean age was 58 ± 16 years, 51% were female, and 78% had cerebrovascular etiology of coma. Fifty-one percent of patients had midline shift on head CT at coma onset and 43 (51%) patients awakened. In a multivariate analysis, independent predictors of awakening were younger age (odds ratio [OR] = 1.039, 95% confidence interval [CI] = 1.002-1.079, p = 0.040), higher GCS score at coma onset (OR = 1.455, 95% CI = 1.157-1.831, p = 0.001), nontraumatic coma etiology (OR = 4.464, 95% CI = 1.011-19.608, p = 0.048), lesser pineal shift on follow-up CT (OR = 1.316, 95% CI = 1.073-1.615, p = 0.009), and reduction or no increase in pineal shift on follow-up CT (OR = 11.628, 95% CI = 2.207-62.500, p = 0.004).

INTERPRETATION

Reversal and/or limitation of lateral brain displacement are associated with acute awakening in comatose patients. These findings suggest objective parameters to guide prognosis and treatment in patients with acute onset of coma.

Assessment of brain midline shift using sonography in neurosurgical ICU patients

Introduction

Brain midline shift (MLS) is a life-threatening condition that requires urgent diagnosis and treatment. We aimed to validate bedside assessment of MLS with Transcranial Sonography (TCS) in neurosurgical ICU patients by comparing it to CT.

Methods

In this prospective single centre study, patients who underwent a head CT were included and a concomitant TCS performed. TCS MLS was determined by measuring the difference between the distance from skull to the third ventricle on both sides, using a 2 to 4 MHz probe through the temporal window. CT MLS was measured as the difference between the ideal midline and the septum pellucidum. A significant MLS was defined on head CT as >0.5 cm.

Results

A total of 52 neurosurgical ICU patients were included. The MLS (mean ± SD) was 0.32 ± 0.36 cm using TCS and 0.47 ± 0.67 cm using CT. The Pearson’s correlation coefficient (r²) between TCS and CT scan was 0.65 (P <0.001). The bias was 0.09 cm and the limits of agreements were 1.10 and -0.92 cm. The area under the ROC curve for detecting a significant MLS with TCS was 0.86 (95% CI =0.74 to 0.94), and, using 0.35 cm as a cut-off, the sensitivity was 84.2%, the specificity 84.8% and the positive likelihood ratio was 5.56.

Conclusions

This study suggests that TCS could detect MLS with reasonable accuracy in neurosurgical ICU patients and that it could serve as a bedside tool to facilitate early diagnosis and treatment for patients with a significant intracranial mass effect.

Delayed neurological deterioration after mild head injury: cause, temporal course, and outcomes

BACKGROUND

Mild head injury (MHI) complicated by an intracranial hemorrhage (ICH) is a common cause of hospital admission after head trauma. Most patients are treated nonoperatively, remain neurologically stable, and are discharged uneventfully. However, a small percentage of patients suffer delayed neurological deterioration (DND). Little is known about the characteristics of DND after an MHI complicated by ICH.

OBJECTIVE

To identify the cause, temporal course, and outcomes of patients who deteriorated neurologically after presenting with MHI and ICH.

METHODS

A retrospective review was performed of all adult patients presenting over 54 consecutive months with MHI and ICH. Patients who were treated nonoperatively after initial head computed tomography and had a subsequent DND (Glasgow Coma Scale score decrease ≥2) were identified. Demographics, neurological status, clinical course, radiographic findings, and outcome data were collected.

RESULTS

Over 54 months, 757 patients with MHI plus ICH were admitted for observation; of these, 31 (4.1%) experienced DND. Eighty-seven percent of patients deteriorated within 24 hours after admission. Twenty-one patients (68%) deteriorated as a result of progressive intracranial hemorrhage, and 10 patients (32%) deteriorated as a result of medical causes. Seven patients (23%) died. Variables significantly associated with mortality included age > 60 years, coagulopathy, and change in Marshall computed tomography classification.

CONCLUSION

The incidence of delayed neurological deterioration after MHI with ICH is low and usually occurs within 24 hours after admission. It results in significant morbidity and mortality if it is the result of progressive intracranial hemorrhage. Further research is needed to identify risk factors that can allow early detection and improve outcomes in these patients.

The impact of time to surgery on outcomes in patients with traumatic brain injury: a literature review

AIM

To review the relationship between the time interval to surgery and outcomes in patients with traumatic brain injury (TBI).

METHODS

A literature review was conducted by employing several search strategies, including electronic database searches and footnote chasing. The quality of the selected studies was assessed in terms of internal and external validity. Data regarding authors, publication year, sample size, surgical procedure, time interval to surgery, and outcome was extracted.

RESULTS

Among 16 finally selected studies, five studies (31.3%) found that patient outcome was significantly affected by the timing of surgery and 11 (68.7%) did not. The impact of time to surgery on outcomes was not significant in most (75%) of the studies targeting patients with severe TBI. The effect of time to surgery on outcome showed different findings depending on the type of surgical procedure. A significant effect of time to surgery on outcome was reported in one (14.2%) of the seven studies targeting patients who underwent haematoma evacuation and in four (44.4%) of the nine studies on patients who underwent decompressive craniectomy.

CONCLUSION

This review shows that current opinion is still divided regarding when to operate. Despite this discrepancy, most authors agree that the timing of decompression is crucial to outcome.

A case of traumatic hematoma in the basal ganglia that showed deterioration after arrival at the hospital

A case of traumatic hematoma in the basal ganglia that showed deterioration after arrival at the hospital was reported. A 65-year-old man crashed into the wall while riding a motorcycle. His Glasgow coma scale was E3V4M6 and showed retrograde amnesia and slight right motor weakness. Because head CT in the secondary trauma survey showed subarachnoid hemorrhage in the right Sylvian fissure and multiple gliding contusions in the left frontal and parietal lobe, he was entered into the intensive care unit for diagnosis of diffuse brain injury. He showed complete muscle weakness of left upper and lower limbs 5 h after the accident. Head CT newly showed hematoma, 2 cm in diameter, in the right basal ganglia. The patient vomited following the CT scan, and so his consciousness suddenly deteriorated into a stupor. We performed head CT again. The hematoma had enlarged to 5 cm at the same lesion and partially expanded into midbrain. The patient died on the 13th day of trauma. Based on retrospective interpretation, we conclude that clinical examinations, follow-up CT scans and blood examinations should be performed frequently as part of ICU management for all TBI patients in the early phase after trauma.

Structural brain injury in sports-related concussion

Object

Sports-related concussions (SRCs) represent a significant and growing public health concern. The vast majority of SRCs produce mild symptoms that resolve within 1–2 weeks and are not associated with imaging-documented changes. On occasion, however, structural brain injury occurs, and neurosurgical management and intervention is appropriate.

Methods

A literature review was performed to address the epidemiology of SRC with a targeted focus on structural brain injury in the last half decade. MEDLINE and PubMed databases were searched to identify all studies pertaining to structural head injury in sports-related head injuries.

Results

The literature review yielded a variety of case reports, several small series, and no prospective cohort studies.

Conclusions

The authors conclude that reliable incidence and prevalence data related to structural brain injuries in SRC cannot be offered at present. A prospective registry collecting incidence, management, and follow-up data after structural brain injuries in the setting of SRC would be of great benefit to the neurosurgical community.

[Non-invasive evaluation of intracranial pressure: how and for whom?]

The invasive monitoring of intracranial pressure is useful in circumstances associated with high-risk of raised intracranial pressure. However the placement of intracranial probe is not always possible and non-invasive assessment of intracranial pressure may be useful, particularly in case of emergencies. Transcranial Doppler measurements allow the estimation of perfusion pressure with the pulsatility index. Recently, new ultrasonographic methods of cerebral monitoring have been developed: the diameter of the optic nerve sheath diameter, a surrogate marker of raised intracranial pressure and the estimation of median shift line deviation.

Transcranial Doppler to screen on admission patients with mild to moderate traumatic brain injury

BACKGROUND

Detecting patients at risk for secondary neurological deterioration (SND) after mild to moderate traumatic brain injury is challenging.

OBJECTIVE

To assess the diagnostic accuracy of transcranial Doppler (TCD) on admission in screening these patients.

METHODS

This prospective, observational cohort study enrolled 98 traumatic brain injury patients with an initial Glasgow Coma Scale score of 9 to 15 whose initial computed tomography (CT) scan showed either absent or mild lesions according to the Trauma Coma Data Bank (TCDB) classification, ie, TCDB I and TCDB II, respectively. TCD measurements of the 2 middle cerebral arteries were obtained on admission under stable conditions in all patients. Neurological outcome was reassessed on day 7.

RESULTS

Of the 98 patients, 21 showed SND, ie, a decrease of ≥ 2 points from the initial Glasgow Coma Scale or requiring any treatment for neurological deterioration. Diastolic cerebral blood flow velocities and pulsatility index measurements were different between patients with SND and patients with no SND. Using receiver-operating characteristic analysis, we found the best threshold limits to be 25 cm/s (sensitivity, 92%; specificity, 76%; area under curve, 0.93) for diastolic cerebral blood flow velocity and 1.25 (sensitivity, 90%; specificity, 91%; area under curve, 0.95) for pulsatility index. According to a recursive-partitioning analysis, TCDB classification and TCD measurements were the most discriminative among variables to detect patients at risk for SND.

CONCLUSION

In patients with no severe brain lesions on CT after mild to moderate traumatic brain injury, TCD on admission, in complement with brain CT scan, could accurately screen patients at risk for SND.

Prognostic predictors of outcome in an operative series in traumatic brain injury patients

BACKGROUND

Although several prognostic factors for traumatic brain injury (TBI) have been evaluated, a useful predictive scoring model for outcome has yet to be developed for TBI patients. The aim of this study was to determine independent predictors and develop a multivariate logistic regression equation to determine prognosis in TBI patients.

METHODS

A total of 13 different variables were evaluated. All 84 patients in this study were retrospectively evaluated between October 2003 and January 2008 and all underwent craniectomy or craniotomy for hematoma removal and were fitted with intracranial pressure (ICP) microsensor monitors. By using univariate, multiple logistic regression and prognostic regression scoring equations it was possible to draw Receiver-Operating Characteristic curves (ROC) to predict Glasgow Outcome Scale (GOS) 6 months after TBI.

RESULTS

We found that patients over 40 years of age (p < 0.001), unresponsive pre-op pupil reaction (p =0.001), pre-op midline shift (p =0.008), higher injury severity score (ISS; p=0.007), and craniectomy (p < 0.05) were associated with poor outcome in patients with TBI. Using ROC curve to predict the probability of unfavorable outcome, the sensitivity was 97.5% and the specificity was 90.7%.

CONCLUSION

In our preliminary findings, five variables to predict poor outcomes 6 months after TBI were useful. These sensitive variables can be used as a referential guideline in our daily practice to decide whether or not to perform advanced management or avoid decompressive craniectomy.

Fluid resuscitation in multiple trauma patients

PURPOSE OF REVIEW

Fluid resuscitation in trauma patients with hemorrhagic shock is controversially discussed in the literature. The coincidence of brain injury complicates management of these patients. This article summarizes the current knowledge on nonblood component fluid resuscitation and choice of fluids in patients with multiple trauma.

RECENT FINDINGS

Whereas current evidence suggests the efficacy of fluid therapy in hemorrhagic shock without active bleeding, experimental and clinical data demonstrate that aggressive volume challenge may be futile or even deleterious in the setting of uncontrolled hemorrhage. Large amounts of isotonic crystalloids may be associated with hypothermia, acidosis and inflammation. In patients with traumatic brain injury hypertonic solutions may positively influence inflammation and intracranial pressure without affecting neurologic outcome or mortality.

SUMMARY

To date no large-scale clinical studies exist to either support or refute the use of nonblood component fluid resuscitation of hemorrhagic shock in trauma patients. The optimal choice of fluid remains to be determined, but existing evidence suggests avoiding crystalloids in favor of hypertonic solutions. The role of modern, iso-oncotic colloids in the treatment of hemorrhagic shock has not yet been sufficiently defined. In patients with concomitant brain injury, arterial hypotension must be avoided and infusion of hypotonic solutions is obsolete, whereas administration of hypertonic solutions may exert beneficial effects beyond hemodynamic stabilization.

Low rate of delayed deterioration requiring surgical treatment in patients transferred to a tertiary care center for mild traumatic brain injury

OBJECT

Patients with mild traumatic brain injury (mTBI) only rarely need neurosurgical intervention; however, there is a subset of patients whose condition will deteriorate. Given the high resource utilization required for interhospital transfer and the relative infrequency of the need for intervention, this study was undertaken to determine how often patients who were transferred required intervention and if there were factors that could predict that need.

METHODS

The authors performed a retrospective review of cases involving patients who were transferred to the University of New Mexico Level 1 trauma center for evaluation of mTBI between January 2005 and December 2009. Information including demographic data, lesion type, need for neurosurgical intervention, and short-term outcome was recorded.

RESULTS

During the 4-year study period, 292 patients (age range newborn to 92 years) were transferred for evaluation of mTBI. Of these 292 patients, 182 (62.3%) had an acute traumatic finding of some kind; 110 (60.4%) of these had a follow-up CT to evaluate progression, whereas 60 (33.0%) did not require a follow-up CT. In 15 cases (5.1% overall), the patients were taken immediately to the operating room (either before or after the first CT). Only 4 patients (1.5% overall) had either clinical or radiographic deterioration requiring delayed surgical intervention after the second CT scan. Epidural hematoma (EDH) and subdural hematoma (SDH) were both found to be significantly associated with the need for surgery (OR 29.5 for EDH, 95% CI 6.6-131.8; OR 9.7 for SDH, 95% CI 2.4-39.1). There were no in-hospital deaths in the series, and 97% of patients were discharged with a Glasgow Coma Scale score of 15.

CONCLUSIONS

Most patients who are transferred with mTBI who need neurosurgical intervention have a surgical lesion initially. Only a very small percentage will have a delayed deterioration requiring surgery, with EDH and SDH being more concerning lesions. In most cases of mTBI, triage can be performed by a neurosurgeon and the patient can be observed without interhospital transfer.

Emergency department skull trephination for epidural hematoma in patients who are awake but deteriorate rapidly

BACKGROUND

Blunt head trauma patients who have been alert but are deteriorating (talk and deteriorate [T&D]) due to a rapidly expanding epidural hematoma (EDH) usually have poor outcome if they must wait for hospital transfer for evacuation. We therefore have continued to teach skull trephination to emergency physicians (EPs). We are unaware of any literature on EP trephination for EDH in the age of computed tomography (CT) scanning.

METHODS

Patients with EDH from blunt trauma, either in our institution or known to our graduate network, who were T&D with anisocoria despite intubation plus medical therapy, and who had pre-transfer EP trephination, were compared to those who were transferred without trephination.

RESULTS

There were 5 patients with blunt trauma and CT-proven EDH who were T&D with anisocoria who underwent Emergency Department (ED) trephination at outlying hospitals before transfer. All 5 had improvement in condition and good outcomes. Three had complete recovery without disability and 2 others had mild disability with good cognitive function. None had complications. Two patients with T&D and anisocoria were transferred without trephination. Both had good neurologic outcomes. The mean time to pressure relief in the trephination group vs. transfer group was 55 vs. 207 min, respectively.

CONCLUSION

In T&D patients with CT-proven EDH and anisocoria, ED skull trephination before transfer resulted in uniformly good outcomes without complications. Time to relief of intracranial pressure was significantly shorter with trephination. Neurologic outcomes were not different.

Fatal head injury in children younger than 2 years in New York City and an overview of the shaken baby syndrome

CONTEXT

Shaken baby syndrome is a controversial topic in forensic pathology. Some forensic pathologists state that shaking alone is insufficient to explain death and that an impact must have occurred even if there is no impact site on the head.

OBJECTIVE

To examine a large cohort of fatal, pediatric head injuries for patterns of specific autopsy findings and circumstances that would support or dispute pure shaking as the cause of death.

DESIGN

We retrospectively reviewed 59 deaths due to head injuries in children younger than 2 years certified in our office during a 9 year period (1998-2006). The review included autopsy, toxicology, microscopy, neuropathology, and police and investigators' reports.

RESULTS

There were 46 homicides, 8 accidents, and 1 undetermined death from blunt-impact injury of the head. In 10 (22%) of the homicides, there was no impact injury to the head, and the cause of death was certified as whiplash shaking. In 4 (40%) of these 10 deaths, there was a history of shaking. In 5 (83%) of the other 6, there was no history of any purported accidental or homicidal injury. All 8 accidental deaths had impact sites. Of the 59 deaths, 4 (6.7%) had only remote injuries (chronic subdural hematomas, remote long bone fractures) that were certified as undetermined cause and manner. These 4 deaths were excluded from the study.

CONCLUSIONS

We describe a subset of fatal, nonaccidental head-injury deaths in infants without an impact to the head. The autopsy findings and circumstances are diagnostic of a nonimpact, shaking mechanism as the cause of death. Fatal, accidental head injuries in children younger than 2 years are rare.

[Can serum protein S100beta predict neurological deterioration after moderate or minor traumatic brain injury?]

INTRODUCTION

Patients with moderate traumatic brain injury (TBI) (Glasgow Coma Scale, GCS, 9-13) or minor TBI (GCS 14-15) are at risk for subsequent neurological deterioration. Serum protein S-100 is believed to reflect brain damage following TBI. In patients with normal or minor CT scan abnormalities on admission, we tested whether the determination of serum protein S-100 beta could predict secondary neurological deterioration.

METHODS

Sixty-seven patients with moderate or minor TBI were prospectively studied. Serum samples were collected on admission within 12 hours postinjury to measure serum protein S-100 levels. Neurological outcome was assessed up to seven days after trauma. Secondary neurological deterioration was defined as two points or more decrease from the initial GCS, or any treatment for neurological deterioration.

RESULTS

Nine patients had a secondary neurological deterioration after trauma. No differences in serum levels of protein S-100 were found between these patients and those without neurological aggravation (n=58 patients): 0.93 microg/l (0.14-4.85) vs 0.39 microg/l (0.04-6.40), respectively. The proportion of patients with abnormal levels of serum protein S-100 at admission according to two admitted cut-off levels (>0.1 and >0.5 microg/l) was comparable between the two groups of patients. Elevated serum levels of protein S-100 were found in patients with Injury Severity Score (ISS) of more than 16 (n=23 patients): 1.26 microg/l (0.14-6.40) vs 0.22 microg/l (0.04-6.20) in patients with ISS less than 16 (n=44 patients).

DISCUSSION

The dosage of serum protein S-100 on admission failed to predict patients at risk for neurological deterioration after minor or moderate TBI. Extracranial injuries can increase serum protein S-100 levels, then limiting the usefulness of this dosage in this clinical setting.

Hemostatic and neuroprotective effects of human recombinant activated factor VII therapy after traumatic brain injury in pigs

Human recombinant activated factor-VII (rFVIIa) has been used successfully in the treatment of spontaneous intracerebral hemorrhage. In addition, there is increasing interest in its use to treat uncontrolled bleeding of other origins, including trauma. The aim of this study was to evaluate the safety and potential effectiveness of rFVIIa to mitigate bleeding using a clinically relevant model of traumatic brain injury (TBI) in the pig. A double injury model was chosen consisting of (1) an expanding cerebral contusion induced by the application of negative pressure to the exposed cortical surface and (2) a rapid rotational acceleration of the head to induce diffuse axonal injury (DAI). Injuries were performed on 10 anesthetized pigs. Five minutes after injury, 720 microg/kg rFVIIa (n=5) or vehicle control (n=5) was administered intravenously. Magnetic resonance imaging (MRI) studies were performed within 30 min and at 3 days post-TBI to determine the temporal expansion of the cerebral contusion. Euthanasia and histopathologic analysis were performed at day 3. This included observations for hippocampal neuronal degeneration, axonal pathology and microclot formation. The expansion of contusion volume over the 3 days post-injury period was reduced significantly in animals treated with rFVIIa compared to vehicle controls. Surprisingly, immunohistochemical analysis demonstrated that the number of dead/dying hippocampal neurons and axonal pathology was reduced substantially by rFVIIa treatment compared to vehicle. In addition, there was no difference in the extent of microthrombi between groups. rFVIIa treatment after TBI in the pig reduced expansion of hemorrhagic cerebral contusion volume without exacerbating the severity of microclot formation. Finally, rFVIIa treatment provided a surprising neuroprotective effect by reducing hippocampal neuron degeneration as well as the extent of DAI.

[Prognostic capacity of brain herniation signs in patients with structural neurological injury]

OBJECTIVE

To determine whether the usual mortality prediction systems (APACHE and SAPS) can be complemented by cranial computed tomography (CT) brain herniation findings in patients with structural neurological involvement.

DESIGN

Prospective cohort study.

SETTING

Trauma ICU in university hospital.

PATIENTS

One hundred and fifty five patients admitted to ICU in 2003 with cranial trauma or acute stroke.

MAIN VARIABLES OF INTEREST

Data were collected on age, diagnosis, mortality, admission cranial CT findings and on APACHE II, APACHE III and SAPS II scores.

RESULTS

Mean age was 47.8 +/- 19.4 years; APACHE II, 17.1 +/- 7.2 points; SAPS II, 43.7 +/- 17.7 points; and APACHE III, 55.8 +/- 29.7 points. Hospital mortality was 36% and mortality predicted by SAPS II was 38%, by APACHE II 30% and by APACHE III 36%. The 56 non-survivors showed greater midline shift on cranial CT scan versus survivors (4.2 +/- 5.5 vs. 1.6 +/- 3.22 mm, p = 0.002) and higher severity as assessed by SAPS II, APACHE II and APACHE III. The mortality rate was significantly higher in patients with subfalcial herniation (61% vs. 30%, p < 0.001). In the multivariate logistic regression analysis, hospital mortality was associated with the likelihood of death according to APACHE III (OR 1.07; 95% CI: 1.05-1.09) and with presence of subfalcial herniation (OR 3.15; 95% CI: 1.07-9.25).

CONCLUSIONS

In critical care patients with structural neurological involvement, cranial CT signs of subfalcial herniation complement the prognostic information given by the usual severity indexes.

Quand faut-il décider d'un transfert en milieu neurochirurgical spécialisé?

The annual incidence of severe head injury lies between 9 and 25/100000 inhabitants, depending on the criteria used for its definition. In most countries, the shortage in neurosurgical ICU beds makes it impossible to take in charge all patients with a severe brain injury. But the beneficial effect of a specialized neurosurgical ICU on outcome after brain injury has been demonstrated in several retrospective studies. Ideally, the best strategy is to admit the patients with a severe head injury directly in a neurosurgical centre. When this is not possible, the appropriate decision of a secondary transfer relies on the quality of the relationships between physicians in the community and the neurosurgical hospitals. Teleradiology is the best method to avoid unnecessary transportation or deleterious delays before transfer. In an era of decreasing medical budgets, technical improvements to enhance medical cooperation should be encouraged.

Correlation of a high D-dimer level with poor outcome in traumatic intracranial hemorrhage

The correlations between D-dimer and Glasgow Coma Scale (GCS), pupillary light reflex, distance of midline shift on brain computed tomography (CT), and Glasgow Outcome Score (GOS) in patients with trauma/non-trauma intracranial hemorrhage (ICH) are not consistent in studies. Ninety-eight traumatic and 59 non-traumatic ICH patients were studied. Pre-existing venous thrombosis, recent surgery, drug use (aspirin or coumadin), or malignancy, were excluded. D-dimer level was estimated within hours after acute insult, and statistical analyses were used for comparisons between groups. Traumatic ICH patients had higher D-dimer levels than controls (2984 vs. 256 microg/l; P = 0.001). The GCS, midline shift on brain CT, pupillary reflex, and GOS at 3 months were significantly correlated with high D-dimer value in traumatic patients (individual P < 0.001), but not in the non-traumatic group. Using receiver-operating characteristic curve (ROC), the cutoff point was 1496 microg/l, with sensitivity and specificity of 100% and 83%, respectively. D-dimer > or =1496 microg/l predicted a poor outcome [adjusted odds ratio (OR) 14.44, 95% CI 1.16-179.27; P = 0.038]. A high D-dimer level is associated with a poor outcome in patients with traumatic ICH. It can be used in addition to neurological assessment to predict the outcome.