Traumatic acute subdural hematoma: major mortality reduction in comatose patients treated within four hours

Short- and Long-Term Geriatric Mortality After Acute Traumatic Subdural Hemorrhage

BACKGROUND

Acute subdural hemorrhage often occurs in those ≥65 years of age after trauma and tends to yield poor clinical outcomes. Previous studies have demonstrated a propensity toward high in-hospital mortality rates in this population; however, postdischarge mortality data are limited. The objective of the present study was to analyze short- and long-term mortality data after acute traumatic subdural hemorrhage in the geriatric population as well as review the impact of associated clinical variables including mechanism of injury, pre-morbid antithrombotic use, and need for surgical decompression on mortality rates.

METHODS

We retrospectively reviewed 455 patients who presented with an isolated traumatic acute subdural hemorrhage to our level-1 trauma center over a 5 year period using our data registry. Patients were then cross-referenced in the National Social Security Death Index for postdischarge mortality rates. United States life tables were used for peer-controlled actuarial comparisons.

RESULTS

Acute traumatic subdural hemorrhage is often a fatal injury in the geriatric population, especially if taking antithrombotics or requiring surgical decompression. Specifically, they have greater in-hospital mortality rates than adults with similar injuries and have significantly lower survival rates for several years following discharge compared with their peer-matched controls.

CONCLUSIONS

Here, we found that age is a significant predictor of both short- and long-term survival after acute traumatic subdural hemorrhage. Moreover, the present study corroborates that the need for surgical decompression or the use of pre-morbid antithrombotic medications is associated with increased overall mortality.

A descriptive study of trauma cases encountered in the Grand M'Bour Hospital Emergency Department in Senegal

Introduction

This study analyzed the trends of trauma cases that presented to the Emergency Department (ED) in the Grand M'Bour Hospital. We examined demographics of patients, mechanisms of trauma and types of injuries that result and times from injury to arrival.

Methods

This was a descriptive study using prospective ED trauma cases. Patients were selected for the study if their chief complaint was related to a traumatic injury. A trauma flow sheet was developed to obtain information. Data was collected from 6/22/16-7/13/16, with 105 cases recorded. Abstracted data included date, time of arrival, time of injury, age, gender, mechanism of injury, injury sustained and disposition.

Results

Patients presented to the ED for 13 different trauma-related reasons. 71% of the patients encountered had a mechanism of injury related to falls or motor vehicle accidents. The majority of patients who suffered from a fall-or motor vehicle-related injury were children, with ages 0-10 representing 31% and ages 11-20 representing 14% of the total patients. While 29% of patients were seen within 1 hour of the time of their injury, 10% of the patients were not seen until days after their injury.

Conclusion

We report that traumatic injuries are most commonly a result of fall-related and vehicle-related accidents. Children under the age of 20 years old are a vulnerable population for traumatic injuries. We observed that many patients were unable to seek care within a day of their injury. This was concerning that proper emergency transportation was not available, leading to potential complications or improper healing of injuries. Knowing these trends, an ED can be better prepared to treat these patients.

Risk factors associated with mortality and survival of acute subdural hematoma: A retrospective study

Background:

Acute subdural hematoma (ASDH) is mostly seen after head injury and is a major cause of morbidity and mortality. We studied the risk factors for ASDH and the effects of these factors on mortality as well as on survival with 100 cases from the rural area of Anatolia region.

Materials and Methods:

One-hundred cases of the ASDH that had been treated surgically between 2011 and 2014, at three different health-care centers from the rural area of Anatolia region, were retrospectively reviewed. Demographic data of patients, etiology, Glasgow Coma Scale (GCS) on admission, survival, presence of comorbid disease, unilaterality or bilaterality of the hematoma, and length of stay in the Intensive Care Unit (ICU) and/or neurosurgery clinic were recorded from the patients’ files.

Results:

The total mortality rate was 34%. Age, etiology, GCS on admission, and laterality of the hematoma (unilateral or bilateral) affected the mortality rates (P = 0.005, P = 0.001, P = 0.001, and P = 0.001, respectively). Advanced age, low GCS on admission, and bilaterality of the hematoma were related with high mortality rates (P = 0.005, P = 0.001, and P = 0.001, respectively). The presence of comorbid disease and gender had no effect on patient survival (P = 0.299 and P = 0.861).

Conclusion:

The most important factors affecting the mortality rate were GCS on admission, etiology, age, and laterality of the hematoma in this study. Advanced age, low GCS on admission, and bilaterality of the hematoma were related with high mortality rates. Etiology had an important role in mortality rates, especially in the pedestrian injury group.

Development of a Three-dimensional Printed Emergent Burr Hole and Craniotomy Simulator

Patients with a traumatic head injury (THI) require immediate surgical intervention, as rapidly expanding intracranial hematomas can be imminently life-threatening, not permitting transfer time to neurosurgical care in a tertiary care center. In rural and remote areas, where neurosurgeons may not be readily available, surgical intervention by Community General Surgeons (CGS) may be required. Currently, the CGS in Newfoundland and Labrador (NL) do not have access to, or have experience training with, an emergent burr hole/craniotomy (EBHC) simulator. One of the barriers is the availability of inexpensive and reliable simulators to practice these skills. Therefore, a low-cost, three-dimensional (3D) printed EBHC simulator was designed and 3D-printed by MUN Med 3D (St John's, NL).

The aim of this technical report is to assess the need for such simulator in rural and remote healthcare centers and report on the iterative development of the EBHC simulator. The 3D-printed EBHC simulator developed by MUN Med 3D was utilized during a general surgery workshop at the 26^th Annual Rural and Remote Medicine Conference in St. John’s, NL. A total of six 3D-printed EBHC simulators were provided for the hour and a half workshop. At the end of the workshop, 16 participants were asked to provide feedback on the need for this simulator in their rural or remote environment as well as feedback on the physical attributes. The feedback received from the participants was overall positive, informative, and supported the need for the 3D-printed EBHC simulator.

Risk Factors for Recurrent Hematoma After Surgery for Acute Traumatic Subdural Hematoma

OBJECTIVE

The development of postcraniotomy hematoma (PCH) after surgery for acute traumatic subdural hematoma (aSDH) has been associated with an increased risk of a poor outcome. The risk factors contributing to PCH remain poorly understood. Our aim was to study the potential risk factors for PCH in a consecutive series of surgically evacuated patients with aSDH.

METHODS

A total of 132 patients with aSDH treated at Turku University Hospital (Turku, Finland) from 2008 to 2012 were enrolled in the present retrospective cohort study. The demographic, clinical, laboratory, and imaging data were collected from the medical records. A comprehensive analysis of the data using 6 different univariate methods, including machine learning and multivariate analyses, was conducted to identify the factors related to PCH.

RESULTS

The incidence of PCH after primary surgery for traumatic aSDH was 10.6%. The patients experiencing PCH were younger (P = 0.04). No difference was found in the use of anticoagulant or antiplatelet medication for the patients with and without PCH. Multivariate analyses identified alcohol inebriation at the time of injury (odds ratio [OR], 12.67; P = 0.041) and hypocapnia (OR, 26.09; P = 0.003) as independent risk factors for PCH. The patients with PCH had had hyponatremia (OR, 0.08; P = 0.018) less often, and their maximal systolic blood pressure was lower (OR, 0.94; P = 0.009). The area under the curve for the multivariate model was 0.96 (P = 0.049), with a Youden index of 0.88.

CONCLUSIONS

The results suggest that alcohol inebriation at the time of injury and hypocapnia during hospitalization are risk factors for the development of PCH.

Predictive Factors of Poor Prognosis After Surgical Management of Traumatic Acute Subdural Hematomas: A Single-Center Series

BACKGROUND

Traumatic acute subdural hematomas (ASDHs) showed the highest mortality of intracranial hematomas. The aim of the current study was to identify predictive factors of poor prognosis among patients who were operated on.

METHODS

This is a single-center retrospective cohort study of 82 patients who underwent surgical evacuation of a traumatic ASDH between January 2009 and December 2016. The epidemiologic, clinical, radiologic, and surgical features were recorded. Postoperative outcome were assessed by the Glasgow Outcome Scale (GOS) score at 6 months. Univariate and multivariate analysis and a classification and regression tree (CART) were performed.

RESULTS

At 6 months, 76% of patients achieved an unfavorable outcome (GOS score 1-3). The context of polytrauma (P = 0.03) and ASDH thickness ≥20 mm (P = 0.02) were significantly associated with poor outcome in the multivariate analysis. The CART algorithm isolated 3 subgroups of patients with an unfavorable prognosis: polytrauma (91%), isolated head injury (HI) featuring an ASDH thickness ≥20 mm (89%), or isolated HI featuring a thickness <20 mm in a patient older than 54 years (71%). Isolated patients with HI younger than 54 years harboring an ASDH <20 mm thick had the most promising results, with 53% with a GOS score of 4 or 5.

CONCLUSIONS

The context of polytrauma, ASDH thickness, and age were major predictive factors of poor prognosis in patients with surgically evacuated traumatic ASDH. The CART algorithm using these features isolated subgroups with decreasingly unfavorable outcome, providing a relevant statistical tool to apply to future studies of traumatic ASDH.

Injury-to-Admission Delay Beyond 4 Hours Is Associated with Worsening Outcomes for Traumatic Brain Injury in Cambodia

BACKGROUND

In Cambodia, the most common victims of traumatic brain injury (TBI) are men 20-30 years of age involved in motor vehicle collision. Secondary injury sustained by these patients occurs during the time period between initial insult and hospital admission. Strengthening prehospital systems for TBI in low- and middle-income countries (LMICs) such as Cambodia is therefore a key element of the development agenda for universal health equity. We report a retrospective analysis of the relationship between prehospital delays and TBI outcomes among patients from a large government hospital in Cambodia.

METHODS

Data were collected from 3476 patients with TBI admitted to a major government hospital in Phnom Penh, Cambodia, from June 2013 to June 2018. Patients with missing data or those admitted >8 hours postinjury were excluded. Statistical analyses examined associations between injury-to-admission delay (IAD) and outcomes such as Glasgow Outcome Scale (GOS) score and length of stay (LOS).

RESULTS

A total of 2125 patients with TBI (76.85% men) were included. The median age was 27 years (interquartile range, 22-37 years). Injury severity at presentation included 1406 mild (66%), 464 moderate (22%), and 240 severe cases (11%). No Glasgow Coma Scale (GCS) data were available for 15 patients (1%). We found an inverse relationship between IAD and GOS score, most evidently for mild and moderate TBI (n = 1870; 88%). Regression analysis revealed a marked decrease in GOS score at the IAD >4-hour threshold. Each 30-minute delay in IAD was correlated with >2-hour increase in LOS for mild (P < 0.001) and moderate TBI (P < 0.001).

CONCLUSIONS

In a retrospective cohort of >2000 patients with TBI from Cambodia, we found that increasing IAD was associated with worsening outcome, especially beyond the 4-hour threshold. These data should inform development of prehospital guidelines for TBI care in LMICs.

Early diagnosis of traumatic intracranial hematomas

Timing of the intervention for intracranial hematomas is critical for its success, specifically since expansion of the hemorrhage can result in debilitating and sometimes fatal outcomes. Led by Britton Chance, we and an extended team from University of Pennsylvania, Baylor and Drexel universities developed a handheld brain hematoma detector for early triage and diagnosis of head trauma victims. After obtaining de novo Food and Drug Administration clearance, over 200 systems are deployed in all Marine battalion aid stations around the world. Infrascanner, a handheld brain hematoma detection system, is based on the differential near-infrared light absorption of the injured versus the noninjured part of brain. About 12 independent studies have been conducted in the USA, Canada, Spain, Italy, the Netherlands, Germany, Russia, Poland, Afghanistan, India, China, and Turkey. Here, we outline the background and design of the device as well as clinical studies with a total of 1293 patients and 203 hematomas. Infrascanner demonstrates high sensitivity (adults: 92.5% and children: 93%) and specificity (adults: 82.9% and children: 86.5%) in detecting intracranial hematomas >3.5  mL in volume and <2.5  cm from the surface of the brain. Infrascanner is a clinically effective screening solution for head trauma patients in prehospital settings where timely triage is critical.

The Role of Decompressive Craniectomy in Traumatic Brain Injury: A Systematic Review and Meta-analysis

The objective is to evaluate the efficacy of early decompressive craniectomy (DC) versus standard medical management ± late DC in improving clinical outcome in patients with traumatic brain injury (TBI). Electronic databases and gray literature (unpublished articles) were searched under different MeSH terms from 1990 to present. Randomized control trials, case–control studies, and prospective cohort studies on DC in moderate and severe TBI. Clinical outcome measures included Glasgow Coma Outcome Scale (GCOS) and extended GCOS, and mortality. Data were extracted to Review Manager software. A total of 45 articles and abstracts that met the inclusion criteria were retrieved and analyzed. Ultimately, seven studies were included in our meta-analysis, which revealed that patients who had early DC had no statistically significant likelihood of having a favorable outcome at 6 months than those who had a standard medical care alone or with late DC (OR of favorable clinical outcome at 6 months: 1.00; 95% confidence interval (CI): 0.75–1.34; P = 0.99). The relative risk (RR) of mortality in early DC versus the standard medical care ± late DC at discharge or 6 months is 0.62; 95% CI: 0.40–0.94; P = 0.03. Subgroup analysis based on RR of mortality shows that the rate of mortality is reduced significantly in the early DC group as compared to the late DC. RR of Mortality is 0.43; 95% CI: 0.26–0.71; P = 0.0009. However, good clinical outcome is the same. Early DC saves lives in patients with TBI. However, further clinical trials are required to prove if early DC improve clinical outcome and to define the best early time frame in performing early DC in TBI population.

Temporal Delays Along the Neurosurgical Care Continuum for Traumatic Brain Injury Patients at a Tertiary Care Hospital in Kampala, Uganda

BACKGROUND

Significant care continuum delays between acute traumatic brain injury (TBI) and definitive surgery are associated with poor outcomes. Use of the "3 delays" model to evaluate TBI outcomes in low- and middle-income countries has not been performed.

OBJECTIVE

To describe the care continuum, using the 3 delays framework, and its association with TBI patient outcomes in Kampala, Uganda.

METHODS

Prospective data were collected for 563 TBI patients presenting to a tertiary hospital in Kampala from 1 June to 30 November 2016. Four time intervals were constructed along 5 time points: injury, hospital arrival, neurosurgical evaluation, computed tomography (CT) results, and definitive surgery. Time interval differences among mild, moderate, and severe TBI and their association with mortality were analyzed.

RESULTS

Significant care continuum differences were observed for interval 3 (neurosurgical evaluation to CT result) and 4 (CT result to surgery) between severe TBI patients (7 h for interval 3 and 24 h for interval 4) and mild TBI patients (19 h for interval 3 and 96 h for interval 4). These postarrival delays were associated with mortality for mild (P = .05) and moderate TBI (P = .03) patients. Significant hospital arrival delays for moderate TBI patients were associated with mortality (P = .04).

CONCLUSION

Delays for mild and moderate TBI patients were associated with mortality, suggesting that quality improvement interventions could target current triage practices. Future research should aim to understand the contributors to delays along the care continuum, opportunities for more effective resource allocation, and the need to improve prehospital logistical referral systems.

Overview of Monitoring of Cerebral Blood Flow and Metabolism after Severe Head Injury

The relationships between cerebral blood flow (CBF), cerebral metabolism (cerebral metabolic rate of oxygen, CMRO2) and cerebral oxygen extraction (arteriovenous difference of oxygen, AVDO2) are discussed, using the formula CMRO2 = CBF × AVDO2. Metabolic autoregulation, pressure autoregulation and viscosity autoregulation can all be explained by the strong tendency of the brain to keep AVDO2 constant. Monitoring of CBF, CMRO2 or AVDO2 very early after injury is impractical, but the available data indicate that cerebral ischemia plays a considerable role at this stage. It can best be avoided by not "treating" arterial hypertension and not using too much hyperventilation, while generous use of mannitol is probably beneficial. Once in the ICU, treatment can most practically be guided by monitoring of jugular bulb venous oxygen saturation. If saturation drops below 50%, the reason for this must be found (high intracranial pressure, blood pressure not high enough, too vigorous hyperventilation, arterial hypoxia, anemia) and must be treated accordingly.

Comparative Effectiveness of Surgery for Traumatic Acute Subdural Hematoma in an Aging Population

There is uncertainty as to the optimal initial management of patients with traumatic acute subdural hematoma, leading to regional variation in surgical policy. This can be exploited to compare the effect of various management strategies and determine best practices. This article reports such a comparative effectiveness analysis of a retrospective observational cohort of traumatic acute subdural hematoma patients in two geographically distinct neurosurgical departments chosen for their - a-priori defined - diverging treatment preferences. Region A favored a strategy focused on surgical hematoma evacuation, whereas region B employed a more conservative approach, performing primary surgery less often. Region was used as a proxy for preferred treatment strategy to compare outcomes between groups, adjusted for potential confounders using multivariable logistic regression with imputation of missing data. In total, 190 patients were included: 108 from region A and 82 from region B. There were 104 males (54.7%). Matching current epidemiological developments, the median age was relatively high at 68 years (interquartile range [IQR], 54-76). Baseline characteristics were comparable between regions. Primary evacuation was performed in 84% of patients in region A and in 65% of patients in region B (p < 0.01). Mortality was lower in region A (37% vs. 45%, p = 0.29), as was unfavorable outcome (53% vs. 62%, p = 0.23). The strategy favoring surgical evacuation was associated with significantly lower odds of mortality (odds ratio [OR]: 0.43; 95% confidence interval [CI]: 0.21-0.88) and unfavorable outcome (OR: 0.53; 95% CI: 0.27-1.02) 3-9 months post-injury. Therefore, in the aging population of patients with acute subdural hematoma, a treatment strategy favoring emergency hematoma evacuation might be associated with lower odds of mortality and unfavorable outcome.

Automatic Estimation of the Optic Nerve Sheath Diameter from Ultrasound Images

We present an algorithm to automatically estimate the diameter of the optic nerve sheath from ocular ultrasound images. The optic nerve sheath diameter provides a proxy for measuring intracranial pressure, a life threating condition frequently associated with head trauma. Early treatment of elevated intracranial pressures greatly improves outcomes and drastically reduces the mortality rate. We demonstrate that the proposed algorithm combined with a portable ultrasound device presents a viable path for early detection of elevated intracranial pressure in remote locations and without access to trained medical imaging experts.

Does time from diagnostic CT until surgical evacuation affect outcome in patients with chronic subdural hematoma?

Background

Chronic subdural hematoma (CSDH) is one of the most common neurosurgical conditions. Patients diagnosed with CSDH’s are often planned for subacute surgery. This means that time from diagnostic CT scan until actual surgery might often be prolonged. There are no previous studies that highlight the effect of delayed intervention in this population.

Method

Patients that underwent surgical evacuation for a CSDH at Skåne University Hospital between 1 January 2015 and 31 December 2016 were included in this retrospective cohort study (n = 179). The primary aim was to determine if time from initial diagnosis by head-CT until surgical evacuation had a significant effect on outcome. The following was assessed by mortality, re-operation, number of days spent in hospital, discharge to home/institution, and functional outcome assessed by GOS. Secondary aims were to evaluate the effect of NOAC, vitamin K antagonists, and antiplatelet drugs on time from CT to surgery and re-operation frequency.

Results

Mean time from diagnostic CT scan until surgery was 76 h. No significant relationship was found between time from CT to surgical evacuation and number of days spent in hospital, discharge to own home/institution, 1-year mortality, or outcome assessed by GOS at discharge from hospital. The clear majority (95.5%) of the patients were GCS ≥ 13 pre-operatively. No correlation could be seen between use of NOAC, vitamin K antagonists, or antiplatelet drugs regarding the risk for reoperation within 6 months, and no correlation between the use of these agents and time from CT to surgery. The 30-day mortality was too low to draw any statistically significant conclusions (n = 4).

Conclusion

In this retrospective cohort study, we could conclude that a delay from initial diagnosis confirming a CSDH to surgical evacuation had no negative effect on outcome when surgery was performed within the time frames and on patients with pre-operatively favorable GCS scores (≥ 13) outlined in our study.

Adjusting for confounding by indication in observational studies: a case study in traumatic brain injury

INTRODUCTION

Observational studies of interventions are at risk for confounding by indication. The objective of the current study was to define the circumstances for the validity of methods to adjust for confounding by indication in observational studies.

PATIENTS AND METHODS

We performed post hoc analyses of data prospectively collected from three European and North American traumatic brain injury studies including 1,725 patients. The effects of three interventions (intracranial pressure [ICP] monitoring, intracranial operation and primary referral) were estimated in a proportional odds regression model with the Glasgow Outcome Scale as ordinal outcome variable. Three analytical methods were compared: classical covariate adjustment, propensity score matching and instrumental variable (IV) analysis in which the percentage exposed to an intervention in each hospital was added as an independent variable, together with a random intercept for each hospital. In addition, a simulation study was performed in which the effect of a hypothetical beneficial intervention (OR 1.65) was simulated for scenarios with and without unmeasured confounders.

RESULTS

For all three interventions, covariate adjustment and propensity score matching resulted in negative estimates of the treatment effect (OR ranging from 0.80 to 0.92), whereas the IV approach indicated that both ICP monitoring and intracranial operation might be beneficial (OR per 10% change 1.17, 95% CI 1.01-1.42 and 1.42, 95% CI 0.95-1.97). In our simulation study, we found that covariate adjustment and propensity score matching resulted in an invalid estimate of the treatment effect in case of unmeasured confounders (OR ranging from 0.90 to 1.03). The IV approach provided an estimate in the similar direction as the simulated effect (OR per 10% change 1.04-1.05) but was statistically inefficient.

CONCLUSION

The effect estimation of interventions in observational studies strongly depends on the analytical method used. When unobserved confounding and practice variation are expected in observational multicenter studies, IV analysis should be considered.

Effect of the Hybrid Emergency Room System on Functional Outcome in Patients with Severe Traumatic Brain Injury

OBJECTIVE

The timely treatment of severe traumatic brain injury (TBI) is essential for limiting the effects of damage; however, there is no consensus regarding an effective method for early intervention. In August 2011, our hospital launched a novel trauma workflow using the hybrid emergency room (ER), consisting of an interventional radiology-computed tomography (CT) unit installed in the trauma resuscitation room to facilitate early interventions. The aim of this study was to evaluate effects of the hybrid ER system on functional outcomes in patients with severe TBI.

METHODS

We conducted a retrospective historical control study of patients with severe TBI (Glasgow Coma Scale score ≤8) who received conventional treatment (August 2007-July 2011) or treatment in the hybrid ER (August 2011-July 2015). The primary end point was unfavorable outcome at 6 months after injury (death, vegetative state, or lower severe disability) as evaluated by the Glasgow Outcome Scale-Extended. Secondary end points included time from arrival to the start of CT examination and emergency intracranial operation. Potential confounders were adjusted with multivariable logistic regressions.

RESULTS

Among 158 included patients, 88 were in the conventional group and 70 were in the hybrid ER group. After model adjustment, the hybrid ER group was significantly associated with a reduction in unfavorable outcomes. Times to CT examination and intracranial operation were significantly shorter in the hybrid ER group than that in the conventional group.

CONCLUSIONS

The hybrid ER system is useful for realizing immediate CT examination and emergency surgery and improving functional outcomes in patients with severe TBI.

Case report on the spontaneous resolution of a traumatic intracranial acute subdural haematoma: evaluation of the guidelines

Rapid spontaneous resolution of traumatic acute subdural haematomas (ASDH) can occur but is rare. We present an 88-year-old female who presents with a large left acute subdural haematoma (ASDH) measuring 18 mm in thickness with midline shift of 10.7 mm. We managed her conservatively based upon good consciousness level and absent neurological deficits. Repeat computed tomography (CT) the following day demonstrated near complete resolution of the ASDH and midline shift regression; a further CT confirmed resolution. Most patients with large ASDH require surgical evacuation; however, in rare cases, they can resolve spontaneously with extreme rapidity. Conservative management can be a valid option in carefully selected cases.

Clinical Outcome of Epidural Hematoma Treated Surgically in the Era of Modern Resuscitation and Trauma Care

OBJECTIVE

Patients from contemporary populations with traumatic brain injury (TBI) resulting from epidural hematoma (EDH) may differ regarding age, comorbidities, and coagulation status. We therefore analyzed predictors for the clinical outcome of patients with EDH treated surgically regarding modern approaches to resuscitation and trauma care.

METHODS

A retrospective observational analysis was carried out. All patients included underwent surgery. The indication for surgery followed international guidelines. Retrospective data evaluation considered data reflecting the effectiveness of trauma care, baseline characteristics, and radiologic findings. In this analysis, we divided patients into 2 groups (isolated EDH vs. EDH plus other intracranial traumatic injuries). The neurologic outcome was assessed at discharge using the Glasgow Outcome Scale.

RESULTS

Two hundred and sixty-eight patients with epidural hematoma, of whom 131 underwent surgery, were treated between January 1997 and December 2012 in our level-1 trauma center. The overall mortality was 6.8% (mortality for patients with Glasgow Outcome Scale score <9, 15%). As expected, factors with a highly significant (P < 0.01) impact on outcome were concomitant with other intracranial injuries, brain midline shift, and higher Injury Severity Score. Alcohol intoxication was a significant (P < 0.05) predictor of an unfavorable outcome. Anticoagulants and Glasgow Coma Scale score at admission had no significant impact on the outcome.

CONCLUSIONS

The outcome for EDH is more favorable than decades ago, most probably reflecting a well-established chain of trauma care. Therefore, EDH is a treatable disease with a high probability of a favorable outcome.

Management of Subdural Hematomas: Part I. Medical Management of Subdural Hematomas

PURPOSE OF REVIEW

Subdural hematomas (SDH) represent common neurosurgical problem associated with significant morbidity, mortality, and high recurrence rates. SDH incidence increases with age; numbers of patients affected by SDH continue to rise with our aging population and increasing number of people taking antiplatelet agents or anticoagulation. Medical and surgical SDH management remains a subject of investigation.

RECENT FINDINGS

Initial management of patients with concern for altered mental status with or without trauma starts with Emergency Neurological Life Support (ENLS) guidelines, with a focus on maintaining ICP < 22 mmHg, CPP > 60 mmHg, MAP 80-110 mmHg, and PaO₂ > 60 mmHg, followed by rapid sequence intubation if necessary, and expedited acquisition of imaging to identify a space-occupying lesion. Patients are administered anti-seizure medications, and their antiplatelet medications or anticoagulation may be reversed if neurosurgical interventions are anticipated, or until hemorrhage is stabilized on imaging. Medical SDH care focuses on (a) management of intracranial hypertension; (b) maintenance of adequate cerebral perfusion; (c) seizure prevention and treatment; (d) maintenance of normothermia, eucarbia, euglycemia, and euvolemia; and (e) early initiation of enteral feeding, mobilization, and physical therapy. Post-operatively, SDH patients require ICU level care and are co-managed by neurointensivists with expertise in treating increased intracranial pressure, seizures, and status epilepticus, as well as medical complications of critical illness. Here, we review various aspects of medical management with a brief overview of pertinent literature and clinical trials for patients diagnosed with SDH.

Efficacy of the All-in-One Therapeutic Strategy for Severe Traumatic Brain Injury: Preliminary Outcome and Limitation

Objective

Despite recent advances in medicine, no significant improvement has been achieved in therapeutic outcomes for severe traumatic brain injury (TBI). In the treatment of severe multiple traumas, accurate judgment and prompt action corresponding to rapid pathophysiological changes are required. Therefore, we developed the “All-in-One” therapeutic strategy for severe TBI. In this report, we present the therapeutic concept and discuss its efficacy and limitations.

Methods

From April 2007 to December 2015, 439 patients diagnosed as having traumatic intracranial injuries were treated at our institution. Among them, 158 patients were treated surgically. The “All-in-One” therapeutic strategy was adopted to enforce all selectable treatments for these patients at the initial stages. The outline of this strategy is as follows: first, prompt trepanation surgery in the emergency room (ER); second, extensive decompression craniotomy (DC) in the operating room (OR); and finally, combined mild hypothermia and moderate barbiturate (H-B) therapy for 3 to 5 days. We performed these approaches on a regular basis rather than stepwise rule. If necessary, internal ecompression surgery and external ventricular drainage were performed in cases in which intracranial pressure could not be controlled.

Results

Trepanation surgery in the ER was performed in 97 cases; among these cases, 46 had hematoma removal surgery and also underwent DC in the OR. Craniotomy was not enforced unless the consciousness level and pupil findings did not improve after previous treatments. H-B therapy was administered in 56 cases. Internal decompression surgery, including evacuation of traumatic intracerebral hematoma, was additionally performed in 12 cases. Three months after injury, the Glasgow Outcome Scale (GOS) score yielded the following results: good recovery in 25 cases (16%), mild disability in 28 (18%), severe disability in 33 (21%), persistent vegetative state in 9 (6%), and death in 63 (40%). Furthermore, 27 (36%) of the 76 most severe patients who had an abnormal response of bilateral eye pupils were life-saving. Because many cases of a GOS score of ≤5 are included in this study, this result must be satisfactory.

Conclusion

This therapeutic strategy without any lose in the appropriate treatment timing can improve the outcomes of the most severe TBI cases. We think that the breakthrough in the treatment of severe TBI will depend on the shift in the treatment policy.

Mechanism for the Rapid Spontaneous Resolution of an Acute Subdural Hematoma and Transformation into a Subdural Hygroma

BACKGROUND

Spontaneous resolution of acute subdural hematomas (SDHs), occurring as the result of a traumatic injury, is well reported in the literature and rapidly resolving SDHs have been reported as well. Although the mechanism behind the rapid resolution of a SDH has not been well understood, there are postulated mechanisms for this phenomenon. The aim of this report is to present a patient who experienced the rapid resolution of a traumatic SDH, which was replaced by a subdural hygroma.

CASE DESCRIPTION

This 25-year-old man presented to the hospital with an acute left-sided SDH after a head-on motor vehicle collision. At the time of presentation, the patient had an acute SDH with 11 mm of midline shift. The hematoma resolved spontaneously within 48 hours and was replaced by a thin subdural hygroma.

CONCLUSIONS

Rapidly resolving SDHs represent a phenomenon that has been well described, although is not entirely understood. The imaging findings of this patient suggest that cerebrospinal fluid washout is a mechanism that promotes acute SDH resolution.

Prehospital and Intrahospital Temporal Intervals in Patients Requiring Emergent Trauma Craniotomy. A 6-Year Observational Study in a Level 1 Trauma Center

OBJECTIVE

According to level 2 evidence, earlier evacuation of acute subdural or epidural hematomas necessitating surgery is associated with better outcome. Hence, guidelines recommend performing these procedures immediately. Literature on the extent and causes of prehospital and intrahospital intervals in patients with trauma requiring emergent craniotomies is almost completely lacking. Studies delineating and refining the interval before thrombolytic agent administration in ischemic stroke have dramatically reduced the door-to-needle time. A similar exercise for trauma-to-decompression time might result in comparable reductions. We aim to map intervals in emergent trauma craniotomies in our level 1 trauma center, screen for associated factors, and propose possible ways to reduce these intervals.

METHODS

We analyzed patients who were primarily referred (1R; n = 45) and secondarily referred (after computed tomography imaging in a community hospital [2R; n = 22]) to our emergency department (ED) and underwent emergent trauma craniotomies between 2010 and 2016.

RESULTS

Median prehospital interval (between emergency call and arrival at the ED) was 42 minutes for 1R patients. Median intrahospital interval (between initial ED arrival and skin incision [SI]) was 140 minutes and 268 minutes for 1R and 2R patients, respectively. In 1R patients, ED-SI interval was positively correlated with Glasgow Coma Scale score (ρ=.49; P < 0.001), but not with age, time of ED arrival, or extended Glasgow Outcome Scale score at 6 months. Based on outlier analysis, we propose prehospital and intrahospital measures to improve performance.

CONCLUSIONS

This is the first report on emergency call-SI interval in emergent trauma craniotomy, with a median of 174 minutes and >297 minutes for 1R and 2R patients, respectively, in our center.

The Optimal Operative Timing of Traumatic Intracranial Acute Subdural Hematoma Correlated with Outcome

Objective

Acute subdural hematoma (ASDH) has been associated with mortality in traumatic brain injury. The timing of surgical evacuation for ASDH has still been controversial. The object of this study was to determine the temporal and clinical factors associated with outcome following surgery for ASDH.

Materials and Methods

The study retrospectively viewed medical records and neuroimaging studies of ASDH patients who underwent surgical evacuation. Surgical outcomes were dichotomized into favorable and unfavorable outcomes, and operative times compared between the groups.

Results

The records of 145 ASDH patients who underwent surgery were reviewed. Almost two-thirds of the patients were admitted for surgical evacuation, of whom 71% underwent a decompressive operation. The temporal variables were as follows: mean time from scene of accident to emergency department (ED) was 70 (Standard deviation [SD] 256.0) min, mean time from ED to obtaining CT of the brain was 45.6 (SD 38.9) min, mean time from brain computed tomographic to operating room arrival was 68.6 (SD 50.0) min, and mean time from ED arrival to skin incision was 160.1 (SD 88.1) min. The mean time from ED arrival to skin incision was significantly shorter in the unfavorable outcome group. Because of this reverse association between time from ED to surgery, multivariate analysis was applied to adjust the timing factors with other clinical factors, and the results indicated that temporal factors were not associated with functional outcome, as features such as increased intracranial pressure due to obliterated basal cistern and brain herniation were significantly associated with functional outcome.

Conclusions

The optimal times for surgical evacuation of ASDH are challenging to estimate because compressed brainstem signs are more important than time factors. ASDH patients with compressed brainstem should have surgery as soon as possible.

The Outcome of Severe Traumatic Brain Injury in Latin America

BACKGROUND

Traumatic brain injury (TBI) disproportionately affects lower- and middle-income countries (LMIC). The factors influencing outcomes in LMIC have not been examined as rigorously as in higher-income countries.

METHODS

This study was conducted to examine clinical and demographic factors influencing TBI outcomes in Latin American LMIC. Data were prospectively collected during a randomized trial of intracranial pressure monitoring in severe TBI and a companion observational study. Participants were aged ≥13 years and admitted to study hospitals with Glasgow Coma Scale score ≤8. The primary outcome was Glasgow Outcome Scale, Extended (GOS-E) score at 6 months. Predictors were analyzed using a multivariable proportional odds model created by forward stepwise selection.

RESULTS

A total of 550 patients were identified. Six-month outcomes were available for 88%, of whom 37% had died and 44% had achieved a GOS-E score of 5-8. In multivariable proportional odds modeling, higher Glasgow Coma Scale motor score (odds ratio [OR], 1.41 per point; 95% confidence interval [CI], 1.23-1.61) and epidural hematoma (OR, 1.83; 95% CI, 1.17-2.86) were significant predictors of higher GOS-E score, whereas advanced age (OR, 0.65 per 10 years; 95% CI, 0.57-0.73) and cisternal effacement (P < 0.001) were associated with lower GOS-E score. Study site (P < 0.001) and race (P = 0.004) significantly predicted outcome, outweighing clinical variables such as hypotension and pupillary examination.

CONCLUSIONS

Mortality from severe TBI is high in Latin American LMIC, although the rate of favorable recovery is similar to that of high-income countries. Demographic factors such as race and study site played an outsized role in predicting outcome; further research is required to understand these associations.

Efficacy of decompressive craniectomy in the management of intracranial pressure in severe traumatic brain injury

Traumatic brain injury (TBI) is a common cause of permanent disability for which clinical management remains suboptimal. Elevated intracranial pressure (ICP) is a common sequela following TBI leading to death and permanent disability if not properly managed. While clinicians often employ stepwise acute care algorithms to reduce ICP, a number of patients will fail medical management and may be considered for surgical decompression. Decompressive craniectomy (DC) involves removing a component of the bony skull to allow cerebral tissue expansion in order to reduce ICP. However, the impact of DC, which is performed in the setting of neurological instability, ongoing secondary injury, and patient resuscitation, has been challenging to study and outcomes are not well understood. This review summarizes historical and recent studies to elucidate indications for DC and the nuances, risks and complications in its application. The pathophysiology driving ICP elevation, and the corresponding medical interventions for their temporization and treatment, are thoroughly described. The current state of DC - including appropriate injury classification, surgical techniques, concurrent medical therapies, mortality and functional outcomes - is presented. We also report on the recent updates from large randomized controlled trials in severe TBI (Decompressive Craniectomy [DECRA] and Randomized Evaluation of Surgery with Craniectomy for Uncontrollable Elevation of ICP [RESCUEicp]), and recommendations for early DC to treat refractory ICP elevations in malignant middle cerebral artery syndrome. Limitations for DC, such as the equipoise between immediate reduction in ICP and clinically meaningful functional outcomes, are discussed in support of future investigations.

Brainstem Monitoring in the Neurocritical Care Unit: A Rationale for Real-Time, Automated Neurophysiological Monitoring

Patients with severe traumatic brain injury or large intracranial space-occupying lesions (spontaneous cerebral hemorrhage, infarction, or tumor) commonly present to the neurocritical care unit with an altered mental status. Many experience progressive stupor and coma from mass effects and transtentorial brain herniation compromising the ascending arousal (reticular activating) system. Yet, little progress has been made in the practicality of bedside, noninvasive, real-time, automated, neurophysiological brainstem, or cerebral hemispheric monitoring. In this critical review, we discuss the ascending arousal system, brain herniation, and shortcomings of our current management including the neurological exam, intracranial pressure monitoring, and neuroimaging. We present a rationale for the development of nurse-friendly-continuous, automated, and alarmed-evoked potential monitoring, based upon the clinical and experimental literature, advances in the prognostication of cerebral anoxia, and intraoperative neurophysiological monitoring.

Decompressive Craniectomy in Patients with Traumatic Brain Injury: Are the Usual Indications Congruent with Those Evaluated in Clinical Trials?

BACKGROUND

In patients with traumatic brain injury (TBI), multicenter randomized controlled trials have assessed decompressive craniectomy (DC) exclusively as treatment for refractory elevation of intracranial pressure (ICP). DC reliably lowers ICP but does not necessarily improve outcomes. However, some patients undergo DC as treatment for impending or established transtentorial herniation, irrespective of ICP.

METHODS

We performed a population-based cohort study assessing consecutive patients with moderate-severe TBI. Indications for DC were compared with enrollment criteria for the DECRA and RESCUE-ICP trials.

RESULTS

Of 644 consecutive patients, 51 (8 %) were treated with DC. All patients undergoing DC had compressed basal cisterns, 82 % had at least temporary preoperative loss of ≥1 pupillary light reflex (PLR), and 80 % had >5 mm of midline shift. Most DC procedures (67 %) were "primary," having been performed concomitantly with evacuation of a space-occupying lesion. ICP measurements influenced the decision to perform DC in 18 % of patients. Only 10 and 16 % of patients, respectively, would have been eligible for the DECRA and RESCUE-ICP trials. DC improved basal cistern compression in 76 %, and midline shift in 94 % of patients. Among patients with ≥1 absent PLR at admission, DC was associated with lower mortality (46 vs. 68 %, p = 0.03), especially when the admission Marshall CT score was 3-4 (p = 0.0005). No patients treated with DC progressed to brain death. Variables predictive of poor outcome following DC included loss of PLR(s), poor motor score, midline shift ≥11 mm, and development of perioperative cerebral infarcts.

CONCLUSIONS

DC is most often performed for clinical and radiographic evidence of herniation, rather than for refractory ICP elevation. Results of previously completed randomized trials do not directly apply to a large proportion of patients undergoing DC in practice.

Acute Management of Traumatic Brain Injury

Traumatic brain injury (TBI) is a leading cause of death and disability in patients with trauma. Management strategies must focus on preventing secondary injury by avoiding hypotension and hypoxia and maintaining appropriate cerebral perfusion pressure (CPP), which is a surrogate for cerebral blood flow. CPP can be maintained by increasing mean arterial pressure, decreasing intracranial pressure, or both. The goal should be euvolemia and avoidance of hypotension. Other factors that deserve important consideration in the acute management of patients with TBI are venous thromboembolism, stress ulcer, and seizure prophylaxis, as well as nutritional and metabolic optimization.

Epidemiology, Management, and Functional Outcomes of Traumatic Brain Injury in Sub-Saharan Africa

BACKGROUND

Trauma accounts for 4.7 million deaths each year, with an estimated 90% of these occurring in low- and middle-income countries (LMICs). Approximately half of trauma-related deaths are caused by central nervous system injury. Because a thorough understanding of traumatic brain injury (TBI) in LMICs is essential to mitigate TBI-related mortality, we established a clinical and radiographic database to characterize TBI in our low-income setting.

METHODS

This is a review of prospectively collected data from Kamuzu Central Hospital, a tertiary care center in the capital of Malawi. All patients admitted from October 2016 through May 2017 with a history of head trauma, altered consciousness, and/or radiographic evidence TBI were included. We performed descriptive statistics, a Cox regression analysis, and a survival analysis.

RESULTS

There were 280 patients who met inclusion criteria; of these, 80.5% were men. The mean age was 28.8 ± 16.3 years. Median Glasgow Coma Scale (GCS) score was 12 (interquartile range, 8-15). Road traffic crashes constituted the most common injury mechanism (60.7%). There were 148 (52.3%) patients who received a computed tomography scan, with the most common findings being contusions (26.1%). Of the patients, 88 (33.0%) had severe TBI, defined as a GCS score ≤8, of whom 27.6% were intubated and 10.3% received tracheostomies. Overall mortality was 30.9%. Of patients who survived, 80.1% made a good recovery. Female sex was protective, and the only significant predictor of poor functional outcome was presence of severe TBI (hazard ratio, 2.98; 95% confidence interval, 1.79-4.95).

CONCLUSIONS

TBI represents a significant part of the global neurosurgical burden of disease. Implementation of proven in-hospital interventions for these patients is critical to attenuate TBI-related morbidity and mortality.

Severe Traumatic Brain Injury at a Tertiary Referral Center in Tanzania: Epidemiology and Adherence to Brain Trauma Foundation Guidelines

BACKGROUND

Severe traumatic brain injury (TBI) is a major cause of death and disability worldwide. Prospective TBI data from sub-Saharan Africa are sparse. This study examines epidemiology and explores management of patients with severe TBI and adherence to Brain Trauma Foundation Guidelines at a tertiary care referral hospital in Tanzania.

METHODS

Patients with severe TBI hospitalized at Bugando Medical Centre were recorded in a prospective registry including epidemiologic, clinical, treatment, and outcome data.

RESULTS

Between September 2013 and October 2015, 371 patients with TBI were admitted; 33% (115/371) had severe TBI. Mean age was 32.0 years ± 20.1, and most patients were male (80.0%). Vehicular injuries were the most common cause of injury (65.2%). Approximately half of the patients (47.8%) were hospitalized on the day of injury. Computed tomography of the brain was performed in 49.6% of patients, and 58.3% were admitted to the intensive care unit. Continuous arterial blood pressure monitoring and intracranial pressure monitoring were not performed in any patient. Of patients with severe TBI, 38.3% received hyperosmolar therapy, and 35.7% underwent craniotomy. The 2-week mortality was 34.8%.

CONCLUSIONS

Mortality of patients with severe TBI at Bugando Medical Centre, Tanzania, is approximately twice that in high-income countries. Intensive care unit care, computed tomography imaging, and continuous arterial blood pressure and intracranial pressure monitoring are underused or unavailable in the tertiary referral hospital setting. Improving outcomes after severe TBI will require concerted investment in prehospital care and improvement in availability of intensive care unit resources, computed tomography, and expertise in multidisciplinary care.

Outcomes Following Exploratory Burr Holes for Traumatic Brain Injury in a Resource Poor Setting

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. The incidence of TBI in low- and middle-income countries (LMICs) is disproportionately high, with an associated increased risk of mortality from TBI relative to high-income countries. Although computed tomography is the diagnostic method of choice, this is often unavailable in LMICs. Exploratory burr holes may provide a suitable choice for diagnosis and treatment of TBI.

METHODS

We performed a retrospective review of prospectively collected data at KCH, a tertiary care center in Lilongwe, Malawi. All trauma patients presenting between June 2012 and July 2015 with a deteriorating level of consciousness and localizing signs and who underwent exploratory burr holes were included. Additionally, we included all patients admitted with TBI, requiring higher-level care during 2011. No patients underwent exploratory burr hole during this time. We performed logistic regression to identify predictors of mortality in the total population of TBI patients.

RESULTS

Among the 241 patients who presented to KCH with TBI requiring higher-level care, the total mortality was 16.4%. More than half (163, or 68%) underwent exploratory burr hole with a mortality of 6.8%. Mortality in patients who did not undergo exploratory burr hole was 43.9%. Upon adjusted logistic regression, not undergoing exploratory burr hole significantly increased the odds of mortality (odds ratio = 12.0, P = 0.000, 95% confidence interval = 4.48-31.9).

CONCLUSION

Exploratory burr holes remain an important diagnostic and therapeutic procedure for TBI in LMICs. Exploratory burr hole technique should be integrated into general surgery education to attenuate TBI-related mortality.

Emergency Trepanation as an Initial Treatment for Acute Subdural Hemorrhage: A Multicenter Retrospective Cohort Study

BACKGROUND

Rapid decompression with trepanation and drainage in an emergency room has been proposed as a potentially effective initial intervention for early-stage acute subdural hemorrhage; however, the actual safety and efficacy of the procedure remain unclear. The aim of this study was to evaluate the feasibility of emergency trepanation as an initial treatment for acute subdural hemorrhage.

METHODS

We investigated patients with thick subdural hemorrhages who had undergone craniotomy between 2004 and 2015 in Japan using a nationwide trauma registry (the Japan Trauma Data Bank). The endpoint was survival at discharge. We compared patients who underwent trepanation in an emergency room with those who did not undergo trepanation, and adjusted for potential confounders using a multivariate logistic regression model.

RESULTS

During the study period, 236,698 patients were registered in the Japan Trauma Data Bank. Of the 1391 patients who were eligible for analysis, 305 had undergone trepanation in an emergency room. The survival rate was 37.7% in patients who had undergone emergency trepanation and 59.3% in those who had not. Performing emergency trepanation was significantly associated with decreased survival even after adjusting for possible confounders (adjusted odds ratio, 0.55; 95% confidence interval, 0.40-0.76; P < 0.001).

CONCLUSIONS

Our results indicate that performing trepanation in an emergency room is associated with a decreased survival rate.

A novel methodology to characterize interfacility transfer strategies in a trauma transfer network

BACKGROUND

More than half of severely injured patients are initially transported from the scene of injury to nontrauma centers (NTCs), with many requiring subsequent transfer to trauma center (TC) care. Definitive care in the setting of severe injury is time sensitive. However, transferring severely injured patients from an NTC is a complex process often fraught with delays. Selection of the receiving TC and the mode of interfacility transport both strongly influence total transfer time and are highly amenable to quality improvement initiatives.

METHODS

We analyzed transfer strategies, defined as the pairing of a destination and mode of transport (land vs. rotary wing vs. fixed wing), for severely injured adult patients. Existing transfer strategies at each NTC were derived from trauma registry data. Geographic Information Systems network analysis was used to identify the strategy that minimized transfer times the most as well as alternate strategies (+15 or +30 minutes) for each NTC. Transfer network efficiency was characterized based on optimality and stability.

RESULTS

We identified 7,702 severely injured adult patients transferred from 146 NTCs to 9 TCs. Nontrauma centers transferred severely injured patients to a median of 3 (interquartile range, 1-4) different TCs and utilized a median of 4 (interquartile range, 2-6) different transfer strategies. After allowing for the use of alternate transfer strategies, 73.1% of severely injured patients were transported using optimal/alternate strategies, and only 40.4% of NTCs transferred more than 90% of patients using an optimal/alternate transfer strategy. Three quarters (75.5%) of transfers occurred between NTCs and their most common receiving TC.

CONCLUSION

More than a quarter of patients with severe traumatic injuries undergoing interfacility transport to a TC in Ontario are consistently transported using a nonoptimal combination of destination and mode of transport. Our novel analytic approach can be easily adapted to different system configurations and provides actionable data that can be provided to NTCs and other stakeholders.

LEVEL OF EVIDENCE

Therapeutic study, level IV.

Aspects on the Physiological and Biochemical Foundations of Neurocritical Care

Neurocritical care (NCC) is a branch of intensive care medicine characterized by specific physiological and biochemical monitoring techniques necessary for identifying cerebral adverse events and for evaluating specific therapies. Information is primarily obtained from physiological variables related to intracranial pressure (ICP) and cerebral blood flow (CBF) and from physiological and biochemical variables related to cerebral energy metabolism. Non-surgical therapies developed for treating increased ICP are based on knowledge regarding transport of water across the intact and injured blood-brain barrier (BBB) and the regulation of CBF. Brain volume is strictly controlled as the BBB permeability to crystalloids is very low restricting net transport of water across the capillary wall. Cerebral pressure autoregulation prevents changes in intracranial blood volume and intracapillary hydrostatic pressure at variations in arterial blood pressure. Information regarding cerebral oxidative metabolism is obtained from measurements of brain tissue oxygen tension (PbtO2) and biochemical data obtained from intracerebral microdialysis. As interstitial lactate/pyruvate (LP) ratio instantaneously reflects shifts in intracellular cytoplasmatic redox state, it is an important indicator of compromised cerebral oxidative metabolism. The combined information obtained from PbtO2, LP ratio, and the pattern of biochemical variables reveals whether impaired oxidative metabolism is due to insufficient perfusion (ischemia) or mitochondrial dysfunction. Intracerebral microdialysis and PbtO2 give information from a very small volume of tissue. Accordingly, clinical interpretation of the data must be based on information of the probe location in relation to focal brain damage. Attempts to evaluate global cerebral energy state from microdialysis of intraventricular fluid and from the LP ratio of the draining venous blood have recently been presented. To be of clinical relevance, the information from all monitoring techniques should be presented bedside online. Accordingly, in the future, the chemical variables obtained from microdialysis will probably be analyzed by biochemical sensors.

Clinical Evaluation of a Microwave-Based Device for Detection of Traumatic Intracranial Hemorrhage

Traumatic brain injury (TBI) is the leading cause of death and disability among young persons. A key to improve outcome for patients with TBI is to reduce the time from injury to definitive care by achieving high triage accuracy. Microwave technology (MWT) allows for a portable device to be used in the pre-hospital setting for detection of intracranial hematomas at the scene of injury, thereby enhancing early triage and allowing for more adequate early care. MWT has previously been evaluated for medical applications including the ability to differentiate between hemorrhagic and ischemic stroke. The purpose of this study was to test whether MWT in conjunction with a diagnostic mathematical algorithm could be used as a medical screening tool to differentiate patients with traumatic intracranial hematomas, chronic subdural hematomas (cSDH), from a healthy control (HC) group. Twenty patients with cSDH and 20 HC were measured with a MWT device. The accuracy of the diagnostic algorithm was assessed using a leave-one-out analysis. At 100% sensitivity, the specificity was 75%—i.e., all hematomas were detected at the cost of 25% false positives (patients who would be overtriaged). Considering the need for methods to identify patients with intracranial hematomas in the pre-hospital setting, MWT shows promise as a tool to improve triage accuracy. Further studies are under way to evaluate MWT in patients with other intracranial hemorrhages.