Mortality from traumatic brain injury

Electrical stimulation methods and protocols for the treatment of traumatic brain injury: a critical review of preclinical research

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of disabilities resulting from cognitive and neurological deficits, as well as psychological disorders. Only recently, preclinical research on electrical stimulation methods as a potential treatment of TBI sequelae has gained more traction. However, the underlying mechanisms of the anticipated improvements induced by these methods are still not fully understood. It remains unclear in which stage after TBI they are best applied to optimize the therapeutic outcome, preferably with persisting effects. Studies with animal models address these questions and investigate beneficial long- and short-term changes mediated by these novel modalities.

METHODS

In this review, we present the state-of-the-art in preclinical research on electrical stimulation methods used to treat TBI sequelae. We analyze publications on the most commonly used electrical stimulation methods, namely transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS) and vagus nerve stimulation (VNS), that aim to treat disabilities caused by TBI. We discuss applied stimulation parameters, such as the amplitude, frequency, and length of stimulation, as well as stimulation time frames, specifically the onset of stimulation, how often stimulation sessions were repeated and the total length of the treatment. These parameters are then analyzed in the context of injury severity, the disability under investigation and the stimulated location, and the resulting therapeutic effects are compared. We provide a comprehensive and critical review and discuss directions for future research. RESULTS AND CONCLUSION: We find that the parameters used in studies on each of these stimulation methods vary widely, making it difficult to draw direct comparisons between stimulation protocols and therapeutic outcome. Persisting beneficial effects and adverse consequences of electrical simulation are rarely investigated, leaving many questions about their suitability for clinical applications. Nevertheless, we conclude that the stimulation methods discussed here show promising results that could be further supported by additional research in this field.

Demographics, Causes, and Outcome of Traumatic Brain Injury among Trauma Cases in Cameroon: A Multi-Center Five Year's Retrospective Study

Traumatic brain injury (TBI) is a huge public health challenge worldwide. Epidemiological monitoring is important to inform healthcare policy. We aimed at determining the prevalence, outcome, and causes of TBI in Cameroon by conducting a 5-year retrospective study in three referral trauma centers. Data on demographics, causes, injury mechanisms, clinical aspects, and discharge status were recorded. Comparisons between two categorical variables were done using Pearson's chi-square test or Fisher's exact test. A total of 6248 cases of TBI were identified of 18,151 trauma cases, yielding a prevalence of 34%. The number of TBI cases increased across the years (915 in 2016, 1406 in 2020). Demographic data and causes of TBI were available for 6248 subjects and detailed data on clinical characteristics on 2178 subjects. Median age was 30.0 (24.0, 41.0) years. Males were more affected (80%). Road traffic incidents (RTIs; 75%) was the main cause of TBI, with professional bike riders being more affected (17%). Computed tomography (CT) imaging was performed in 67.7% of cases. Of the 597 (27.4%) cases who did not undergo neuroimaging, 311 (52.1%) did not have neuroimaging performed because of financial constraints, among which 7% were severe TBI cases. A total of 341 (19.6%) patients were discharged against medical advice, of which 83% had financial limitations. Mortality was 10.3% (225 of 2178) in the overall population, but disproportionately high in patients with severe TBI (55%) compared to those in high-income settings (27%). TBI occurrence is high in Cameroon, and RTIs are the main causes. Disparities in care provision were identified as attributable to financial constraints regarding CT scanning and continuation of care. The data presented can inform preventive interventions to improve care provision and transport policies. Implementation of a universal health insurance may be expected to improve hospital care and reduce the adverse effects of TBI among Cameroonians.

Brain Trauma, Glucocorticoids and Neuroinflammation: Dangerous Liaisons for the Hippocampus

Glucocorticoid-dependent mechanisms of inflammation-mediated distant hippocampal damage are discussed with a focus on the consequences of traumatic brain injury. The effects of glucocorticoids on specific neuronal populations in the hippocampus depend on their concentration, duration of exposure and cell type. Previous stress and elevated level of glucocorticoids prior to pro-inflammatory impact, as well as long-term though moderate elevation of glucocorticoids, may inflate pro-inflammatory effects. Glucocorticoid-mediated long-lasting neuronal circuit changes in the hippocampus after brain trauma are involved in late post-traumatic pathology development, such as epilepsy, depression and cognitive impairment. Complex and diverse actions of the hypothalamic–pituitary–adrenal axis on neuroinflammation may be essential for late post-traumatic pathology. These mechanisms are applicable to remote hippocampal damage occurring after other types of focal brain damage (stroke, epilepsy) or central nervous system diseases without obvious focal injury. Thus, the liaisons of excessive glucocorticoids/dysfunctional hypothalamic–pituitary–adrenal axis with neuroinflammation, dangerous to the hippocampus, may be crucial to distant hippocampal damage in many brain diseases. Taking into account that the hippocampus controls both the cognitive functions and the emotional state, further research on potential links between glucocorticoid signaling and inflammatory processes in the brain and respective mechanisms is vital.

Lactate Albumin Ratio Is Associated With Mortality in Patients With Moderate to Severe Traumatic Brain Injury

Background

Traumatic brain injury (TBI) is a serious public health issue all over the world. This study was designed to evaluate the prognostic value of lactate to albumin ratio (LAR) on patients with moderate to severe TBI.

Methods

Clinical data of 273 moderate to severe TBI patients hospitalized in West China Hospital between May 2015 and January 2018 were collected. Multivariate logistic regression analyses were used to explore risk factors and construct a prognostic model of in-hospital mortality in this cohort. A receiver operating characteristic (ROC) curve was drawn to evaluate the discriminative ability of this model.

Results

Non-survivors had higher LAR than survivors (1.09 vs. 0.53, p < 0.001). Results of multivariate logistic regression analysis showed that Glasgow Coma Scale (GCS; odds ratio [OR] = 0.743, p = 0.001), blood glucose (OR = 1.132, p = 0.005), LAR (OR = 1.698, p = 0.022), subdural hematoma (SDH; OR = 2.889, p = 0.006), intraparenchymal hemorrhage (IPH; OR = 2.395, p = 0.014), and diffuse axonal injury (DAI; OR = 2.183, p = 0.041) were independent risk factors of in-hospital mortality in included patients. These six factors were utilized to construct the prognostic model. The area under the ROC curve (AUC) values of single lactate, albumin, and LAR were 0.733 (95% Cl; 0.673–0.794), 0.740 (95% Cl; 0.683–0.797), and 0.780 (95% Cl; 0.725–0.835), respectively. The AUC value of the prognostic model was 0.857 (95%Cl; 0.812–0.901), which was higher than that of LAR (Z = 2.1250, p < 0.05).

Conclusions

Lactate to albumin ratio is a readily available prognostic marker of moderate to severe TBI patients. A prognostic model incorporating LAR is beneficial for clinicians to evaluate possible progression and make treatment decisions in TBI patients.

Correlation of Positive End-Expiratory and Intracranial Pressure Using the Ultrasonographic-Guided Measurement of Optic Nerve Sheath Diameter in Traumatic Brain Injury Patients

BACKGROUND

In brain injury patients, positive end-expiratory pressure (PEEP) may potentially increase the intracranial pressure (ICP). ICP can be noninvasively assessed from the sonographic measurement of the optic nerve sheath diameter (ONSD). Herein, we aim to evaluate the association between PEEP and ICP via measuring ONSD in traumatic brain injury (TBI) patients.

METHODS

TBI patients with age ≥18 years, severe brain injury (GCS 8 or less), receiving mechanical ventilation, initial PEEP ≤4 mmHg and no history of severe cardiopulmonary disease were included in this study. Patients with intracranial hypertension (defined as ICP >20 mmHg) and already receiving PEEP >15 cm H2O at enrollment were excluded from the study. ONSD measurement was performed when hemodynamic parameters were most stable. Variables included central venous pressure, invasive blood pressure, heart rate, saturation, and ventilator parameters.

RESULTS

The ONSD and ICP did not increase significantly while PEEP increased from 0-5 cm and 5-10 cm H2O. However, ONSD and ICP significantly increased when PEEP increased from 10-15 cm H2O. There was no significant difference noted while comparing measurements of optic nerve sheath (ONS) diameter in both eyes at all PEEP values in cases as well as control patients. Mean arterial pressure (MAP) decreased with an increase in PEEP value. Highly significant decrease occurred in MAP change from PEEP 10-15 in cases (P < 0.001) and control (P < 0.001).

CONCLUSIONS

The PEEP up to 10 cm H2O can be safely applied in patients with TBI. In addition, the increment of PEEP might further increase the oxygenation, at the cost of ICP accentuation.

Cerebral Microbleeds May Be Less Detectable by Susceptibility Weighted Imaging MRI From 24 to 72 Hours After Traumatic Brain Injury

Purpose: A former rodent study showed that cerebral traumatic microbleeds (TMBs) may temporarily become invisible shortly after injury when detected by susceptibility weighted imaging (SWI). The present study aims to validate this phenomenon in human SWI.

Methods: In this retrospective study, 46 traumatic brain injury (TBI) patients in various forms of severity were included and willingly complied with our strict selection criteria. Clinical parameters potentially affecting TMB count, Rotterdam and Marshall CT score, Mayo Clinic Classification, contusion number, and total volume were registered. The precise time between trauma and MRI [5 h 19 min to 141 h 54 min, including SWI and fluid-attenuated inversion recovery (FLAIR)] was individually recorded; TMB and FLAIR lesion counts were assessed. Four groups were created based on elapsed time between the trauma and MRI: 0–24, 24–48, 48–72, and >72 h. Kruskal–Wallis, ANOVA, Chi-square, and Fisher’s exact tests were used to reveal differences among the groups within clinical and imaging parameters; statistical power was calculated retrospectively for each comparison.

Results: The Kruskal–Wallis ANOVA with Conover post hoc analysis showed significant (p = 0.01; 1−β > 0.9) median TMB number differences in the subacute period: 0–24 h = 4.00 (n = 11); 24–48 h = 1 (n = 14); 48–72 h = 1 (n = 11); and 72 h ≤ 7.5 (n = 10). Neither clinical parameters nor FLAIR lesions depicted significant differences among the groups.

Conclusion: Our results demonstrate that TMBs on SWI MRI may temporarily become less detectable at 24–72 h following TBI.

Neuroinflammation and Neuronal Loss in the Hippocampus Are Associated with Immediate Posttraumatic Seizures and Corticosterone Elevation in Rats

Hippocampal damage after traumatic brain injury (TBI) is associated with late posttraumatic conditions, such as depression, cognitive decline and epilepsy. Mechanisms of selective hippocampal damage after TBI are not well understood. In this study, using rat TBI model (lateral fluid percussion cortical injury), we assessed potential association of immediate posttraumatic seizures and changes in corticosterone (CS) levels with neuroinflammation and neuronal cell loss in the hippocampus. Indices of distant hippocampal damage (neurodegeneration and neuroinflammation) were assessed using histological analysis (Nissl staining, Iba-1 immunohistochemical staining) and ELISA (IL-1β and CS) 1, 3, 7 and 14 days after TBI or sham operation in male Wistar rats (n = 146). IL-1β was elevated only in the ipsilateral hippocampus on day 1 after trauma. CS peak was detected on day 3 in blood, the ipsilateral and contralateral hippocampus. Neuronal cell loss in the hippocampus was demonstrated bilaterally; in the ipsilateral hippocampus it started earlier than in the contralateral. Microglial activation was evident in the hippocampus bilaterally on day 7 after TBI. The duration of immediate seizures correlated with CS elevation, levels of IL-1β and neuronal loss in the hippocampus. The data suggest potential association of immediate post-traumatic seizures with CS-dependent neuroinflammation-mediated distant hippocampal damage.

Impact of nursing education and a monitoring tool on outcomes in traumatic brain injury

Introduction

Throughout the world, traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality. Low-and middle-income countries experience an especially high burden of TBI. While guidelines for TBI management exist in high income countries, little is known about the optimal management of TBI in low resource settings. Prevention of secondary injuries is feasible in these settings and has potential to improve mortality.

Methods

A pragmatic quasi-experimental study was conducted in the emergency centre (EC) of Mulago National Referral Hospital to evaluate the impact of TBI nursing education and use of a monitoring tool on mortality. Over 24 months, data was collected on 541 patients with moderate (GCS9-13) to severe (GCS≤8) TBI. The primary outcome was in-hospital mortality and secondary outcomes included time to imaging, time to surgical intervention, time to advanced airway, length of stay and number of vital signs recorded.

Results

Data were collected on 286 patients before the intervention and 255 after. Unadjusted mortality was higher in the post-intervention group but appeared to be related to severity of TBI, not the intervention itself. Apart from number of vital signs, secondary outcomes did not differ significantly between groups. In the post-intervention group, vital signs were recorded an average of 2.85 times compared to 0.49 in the pre-intervention group (95% CI 2.08-2.62, p ≤ 0.001). The median time interval between vital signs in the post-intervention group was 4.5 h (IQR 2.1-10.6).

Conclusion

Monitoring of vital signs in the EC improved with nursing education and use of a monitoring tool, however, there was no detectable impact on mortality. The high mortality among patients with TBI underscores the need for treatment strategies that can be implemented in low resource settings. Promising approaches include improved monitoring, organized trauma systems and protocols with an emphasis on early aggressive care and primary prevention.

Surgical Management of Trauma-Related Intracranial Hemorrhage-a Review

PURPOSE OF REVIEW

The surgical management of trauma-related intracranial hemorrhage is characterized by marked heterogeneity. Large prospective randomized trials have generally been prohibited by the ubiquity of concordant pathology, diversity of trauma systems, and paucity of clinical equipoise among providers.

RECENT FINDINGS

To date, the results of retrospective studies and surgeon preference have driven the indications, modality, extent, and timing of surgical intervention in the global neurosurgical community. With advances in our understanding of the pathophysiology of hemorrhagic TBI and the advent of novel surgical techniques, a reevaluation of surgical indication, timing, and approach is warranted. In this way, we can work to optimize surgical outcomes, achieving maximal functional recovery while minimizing surgical morbidity.

Crosstalk of Brain and Bone-Clinical Observations and Their Molecular Bases

As brain and bone disorders represent major health issues worldwide, substantial clinical investigations demonstrated a bidirectional crosstalk on several levels, mechanistically linking both apparently unrelated organs. While multiple stress, mood and neurodegenerative brain disorders are associated with osteoporosis, rare genetic skeletal diseases display impaired brain development and function. Along with brain and bone pathologies, particularly trauma events highlight the strong interaction of both organs. This review summarizes clinical and experimental observations reported for the crosstalk of brain and bone, followed by a detailed overview of their molecular bases. While brain-derived molecules affecting bone include central regulators, transmitters of the sympathetic, parasympathetic and sensory nervous system, bone-derived mediators altering brain function are released from bone cells and the bone marrow. Although the main pathways of the brain-bone crosstalk remain ‘efferent’, signaling from brain to bone, this review emphasizes the emergence of bone as a crucial ‘afferent’ regulator of cerebral development, function and pathophysiology. Therefore, unraveling the physiological and pathological bases of brain-bone interactions revealed promising pharmacologic targets and novel treatment strategies promoting concurrent brain and bone recovery.

Mitochondria as a target for neuroprotection: role of methylene blue and photobiomodulation

Mitochondrial dysfunction plays a central role in the formation of neuroinflammation and oxidative stress, which are important factors contributing to the development of brain disease. Ample evidence suggests mitochondria are a promising target for neuroprotection. Recently, methods targeting mitochondria have been considered as potential approaches for treatment of brain disease through the inhibition of inflammation and oxidative injury. This review will discuss two widely studied approaches for the improvement of brain mitochondrial respiration, methylene blue (MB) and photobiomodulation (PBM). MB is a widely studied drug with potential beneficial effects in animal models of brain disease, as well as limited human studies. Similarly, PBM is a non-invasive treatment that promotes energy production and reduces both oxidative stress and inflammation, and has garnered increasing attention in recent years. MB and PBM have similar beneficial effects on mitochondrial function, oxidative damage, inflammation, and subsequent behavioral symptoms. However, the mechanisms underlying the energy enhancing, antioxidant, and anti-inflammatory effects of MB and PBM differ. This review will focus on mitochondrial dysfunction in several different brain diseases and the pathological improvements following MB and PBM treatment.

Efficacy and Safety of Wendan Decoction for Acute Brain Injury: A Randomized Controlled Study

Objectives: Despite the remarkable advances in critical care management of acute brain injury for the past 20 years, the prognoses remain poor. However, numerous reports indicate the efficacy of Traditional Chinese Medicine (TCM) therapy in stroke rehabilitation. This study aimed to determine the efficacy and safety of integrated TCM (Wendan decoction [WDD]) in patients with acute brain injury as a combination therapy in the early stages. Design: Prospective randomized controlled trial. Setting: Single-center study. Subjects: Sixty patients diagnosed with acute brain injury were randomly assigned to intervention and control groups, equally, and 41 patients completed the study. Interventions: All patients were treated by conventional neurologic intensive care. The 23 patients in the intervention group were administered with an integrated WDD in the early stages three times daily; combination treatment was initiated within 14 days and lasted >1 month. Outcome measures: Duration of ventilator use, intensive care unit stays, Glasgow Coma Scale (GCS) scores, motor response, the best muscle power, disability rating scale (DRS) scores, modified Rankin scale (mRS) scores, and the mortality rate for the first month. The other outcome measures were GCS scores, motor response, the best muscle power, DRS, mRS, and Barthel index (BI) scores 6 months later. Results: There was no mortality in the intervention group, but the rate was 39% in the control group for first month. Comparisons between groups showed significant differences (p < 0.05) in GCS, DRS, mRS, and BI scores, indicating improvements in the intervention group after 6 months. Conclusions: In the early stages of acute brain injury, combination treatment with WDD was found to be safe. Furthermore, this treatment may improve neurologic functional outcomes after 6 months.

Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury

BACKGROUND

Increased intracranial pressure has been shown to be strongly associated with poor neurological outcomes and mortality for patients with acute traumatic brain injury. Currently, most efforts to treat these injuries focus on controlling the intracranial pressure. Hypertonic saline is a hyperosmolar therapy that is used in traumatic brain injury to reduce intracranial pressure. The effectiveness of hypertonic saline compared with other intracranial pressure-lowering agents in the management of acute traumatic brain injury is still debated, both in the short and the long term.

OBJECTIVES

To assess the comparative efficacy and safety of hypertonic saline versus other intracranial pressure-lowering agents in the management of acute traumatic brain injury.

SEARCH METHODS

We searched Cochrane Injuries' Specialised Register, CENTRAL, PubMed, Embase Classic+Embase, ISI Web of Science: Science Citation Index and Conference Proceedings Citation Index-Science, as well as trials registers, on 11 December 2019. We supplemented these searches with searches of four major Chinese databases on 19 September 2018. We also checked bibliographies, and contacted trial authors to identify additional trials.

SELECTION CRITERIA

We sought to identify all randomised controlled trials (RCTs) of hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury of any severity. We excluded cross-over trials as incompatible with assessing long-term outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results to identify potentially eligible trials and extracted data using a standard data extraction form. Outcome measures included: mortality at end of follow-up (all-cause); death or disability (as measured by the Glasgow Outcome Scale (GOS)); uncontrolled intracranial pressure (defined as failure to decrease the intracranial pressure to target and/or requiring additional intervention); and adverse events e.g. rebound phenomena; pulmonary oedema; acute renal failure during treatment).

MAIN RESULTS

Six trials, involving data from 287 people, met the inclusion criteria. The majority of participants (91%) had a diagnosis of severe traumatic brain injury. We had concerns about particular domains of risk of bias in each trial, as physicians were not reliably blinded to allocation, two trials contained participants with conditions other than traumatic brain injury and in one trial, we had concerns about missing data for important outcomes. The original protocol was available for only one trial and other trials (where registered) were registered retrospectively. Meta-analysis for both the primary outcome (mortality at final follow-up) and for 'poor outcome' as per conventionally dichotomised GOS criteria, was only possible for two trials. Synthesis of long-term outcomes was inhibited by the fact that two trials ceased data collection within two hours of a single bolus dose of an intracranial pressure-lowering agent and one at discharge from the intensive care unit (ICU). Only three trials collected data after participants were released from hospital, one of which did not report mortality and reported a 'poor outcome' by GOS criteria in an unconventional way. Substantial missing data in a key trial meant that in meta-analysis we report 'best-case' and 'worst-case' estimates alongside available case analysis. In no scenario did we discern a clear difference between treatments for either mortality or poor neurological outcome. Due to variation in modes of drug administration (including whether it followed or did not follow cerebrospinal fluid (CSF) drainage, as well as different follow-up times and ways of reporting changes in intracranial pressure, as well as no uniform definition of 'uncontrolled intracranial pressure', we did not perform meta-analysis for this outcome and report results narratively, by individual trial. Trials tended to report both treatments to be effective in reducing elevated intracranial pressure but that hypertonic saline had increased benefits, usually adding that pretreatment factors need to be considered (e.g. serum sodium and both system and brain haemodynamics). No trial provided data for our other outcomes of interest. We consider evidence quality for all outcomes to be very low, as assessed by GRADE; we downgraded all conclusions due to imprecision (small sample size), indirectness (due to choice of measurement and/or selection of participants without traumatic brain injury), and in some cases, risk of bias and inconsistency. Only one of the included trials reported data on adverse effects; a rebound phenomenon, which was present only in the comparator group (mannitol). None of the trials reported data on pulmonary oedema or acute renal failure during treatment. On the whole, trial authors do not seem to have rigorously sought to collect data on adverse events.

AUTHORS' CONCLUSIONS

This review set out to find trials comparing hypertonic saline to a potential range of other intracranial pressure-lowering agents, but only identified trials comparing it with mannitol or mannitol in combination with glycerol. Based on limited data, there is weak evidence to suggest that hypertonic saline is no better than mannitol in efficacy and safety in the long-term management of acute traumatic brain injury. Future research should be comprised of large, multi-site trials, prospectively registered, reported in accordance with current best practice. Trials should investigate issues such as the type of traumatic brain injury suffered by participants and concentration of infusion and length of time over which the infusion is given.

Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury

BACKGROUND

Increased intracranial pressure (ICP) has been shown to be strongly associated with poor neurological outcomes and mortality for patients with acute traumatic brain injury (TBI). Currently, most efforts to treat these injuries focus on controlling the ICP. Hypertonic saline (HTS) is a hyperosmolar therapy that is used in traumatic brain injury to reduce intracranial pressure. The effectiveness of HTS compared with other ICP-lowering agents in the management of acute TBI is still debated, both in the short and the long term.

OBJECTIVES

To assess the comparative efficacy and safety of hypertonic saline versus other ICP-lowering agents in the management of acute TBI.

SEARCH METHODS

We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library, PubMed, Embase Classic+Embase (OvidSP), ISI Web of Science: Science Citation Index and Conference Proceedings Citation Index-Science, as well as trials registers, on 11 December 2019. We supplemented these searches using four major Chinese databases on 19 September 2018. We also checked bibliographies, and contacted study authors to identify additional studies.

SELECTION CRITERIA

We sought to identify all randomised controlled trials (RCTs) of HTS versus other intracranial pressure-lowering agents for people with acute TBI of any severity. We excluded cross-over trials as incompatible with assessing long term outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results to identify potentially eligible trials and extracted data using a standard data extraction form. Outcome measures included: mortality at end of follow-up (all-cause); death or disability (as measured by the Glasgow Outcome Scale (GOS)); uncontrolled ICP (defined as failure to decrease the ICP to target and/or requiring additional intervention); and adverse events (AEs) (e.g. rebound phenomena; pulmonary oedema; acute renal failure during treatment).

MAIN RESULTS

Six trials, involving data from 295 people, met the inclusion criteria. The majority of participants (89%) had a diagnosis of severe TBI. We had concerns about particular domains of risk of bias in each trial, as physicians were not reliably blinded to allocation, two trials contained participants with conditions other than TBI and in one trial, there were concerns about missing data for important outcomes. The original protocol was available for only one study and other trials (where registered) were registered retrospectively. Meta-analysis for both the primary outcome (mortality at final follow up) and for 'poor outcome' as per conventionally dichotomised GOS criteria, was only possible for two studies. Synthesis of long-term outcomes was inhibited by the fact that two ceased data collection within two hours of a single bolus dose of an ICP-lowering agent and one at discharge from ICU. Only three studies collected data after release from hospital. Due to variation in modes of drug administration, follow-up times, and ways of reporting changes in ICP, as well as no uniform definition of 'uncontrolled ICP', we did not perform meta-analysis for this outcome and report results narratively, by individual trial. Trials tended to report both treatments to be effective in reducing elevated ICP but that HTS had increased benefits, usually adding that pretreatment factors need to be considered (e.g. serum sodium and both system and brain hemodynamics). No trial provided data for our other outcomes of interest. Evidence for all outcomes is considered very low, as assessed by GRADE. All conclusions were downgraded due to imprecision (small sample size), indirectness (due to choice of measurement and/or selection of patients without TBI), and in some cases, risk of bias and inconsistency. Only one of the included trials reported data on adverse effects (AEs) - a rebound phenomenon, which was present only in the comparator group (mannitol). No data were reported on pulmonary oedema or acute renal failure during treatment. On the whole, investigators do not seem to have rigorously sought to collect data on AEs.

AUTHORS' CONCLUSIONS

This review set out to find trials comparing HTS to a potential range of other ICP-lowering agents, but only identified trials comparing it with mannitol or mannitol in combination with glycerol. Based on limited data, there is weak evidence to suggest that HTS is no better than mannitol in efficacy and safety in the long-term management of acute TBI. Future research should be comprised of large, multi-site trials, prospectively registered, reported in accordance with current best practice. Issues such as the type of TBI suffered by participants and concentration of infusion and length of time over which the infusion is given should be investigated.

A Comparative Analysis Between Four-Quadrant Osteoplastic Decompressive Craniotomy versus Conventional Decompressive Craniectomy for Traumatic Brain Injury

OBJECTIVE

Primary decompressive craniectomy (DC) is indicated to evacuate the hematoma and reduce intracranial pressure in traumatic brain injury (TBI). However, there are a myriad of complications because of absence of the bone flap. A novel technique, four-quadrant osteoplastic decompressive craniotomy (FoQOsD) retains the bone flap while achieving adequate cerebral decompression.

METHODS

A single-center randomized controlled trial of 115 patients with TBI needing decompressive surgery was conducted. Of these patients, 59 underwent DC and 56 underwent FoQOsD. The primary outcome determined was functional status at 6 months using the Glasgow Outcome Scale-Extended.

RESULTS

No significant differences were identified in baseline characteristics between both groups. Mean Glasgow Outcome Scale-Extended score was comparable at 6 months (4.28 in DC vs. 4.38 in FoQOsD; P = 0.856). Further, 22 of 58 patients in the DC group had died (38%) compared with 25 of 55 patients in the FoQOsD group (44.6%) (odds ratio [OR], 1.19; 95% confidence interval [CI], 0.6-2.36; P = 0.6) (1 patient lost to follow-up in each group). A favorable outcome was seen in 56.8% of patients in the DC group versus 54.4% of patients in the FoQOsD group (P = 0.74). Presence of intraventricular hemorrhage and subarachnoid hemorrhage (OR, 7.17; 95% CI, 1.364-37.7; P = 0.020), opposite side contusions (OR, 3.838; 95% CI, 1.614-9.131; P = 0.002) and anisocoria (OR, 3.235; 95% CI, 1.490-7.026; P = 0.003) preoperatively were individual factors that played a significant role in final outcome.

CONCLUSIONS

FoQOsD is as efficacious as conventional DC with the added benefit of avoiding a second surgery. The procedure is associated with better cosmesis and fewer complications.

The Use of Computed Tomography Perfusion on Admission to Predict Outcomes in Surgical and Nonsurgical Traumatic Brain Injury Patients

Introduction: The objective of this study was to investigate if data obtained from a computed tomography (CT) perfusion study on admission could correlate to outcomes for the patient, including the patient’s length of stay in the hospital and their initial and final Glasgow Coma Scale (GCS), as well as the modified Rankin Scale (mRS) on discharge. We present an initial subset of patients fulfilling the inclusion criteria: over the age of 18 with mild, moderate, or severe traumatic brain injury (TBI). Patients admitted with a diagnosis of TBI had CT perfusion studies performed within 48 hours of admission. GCS, length of stay, mRS, and discharge location were tracked, along with the patient’s course of hospitalization. Initial results and discussion on the utility of CT perfusion for predicting outcomes are presented.

Methods: Patients exhibiting mild, moderate, or severe TBI were assessed using CT perfusion within 48 hours of admission from January to July 2019 at the Arrowhead Regional Medical Center (ARMC). The neurosurgery census and patient records were assessed for progression of outcomes. Data obtained from the perfusion scans were correlated to patient outcomes to evaluate the utility of CT perfusion in predicting outcomes in surgical and nonsurgical TBI patients.

Results: Preliminary data were obtained on six patients exhibiting TBI, ranging from mild to severe. The mean GCS of our patient cohort on admission was eight, with the most common mechanism of injury found to be falls (50%) and motor vehicle accidents (50%). Cerebral blood volume (CBV) seemed to increase with Rankin value (Pearson's correlations coefficient = 0.43 but was statistically insignificant (P = 0.21)). Cerebral blood flow (CBF) was found to be correlated with CBV, and both increased with Rankin score (Pearson's correlation coefficient = 0.56) but were statistically insignificant (P = 0.27). These results suggest that with a larger sample size, CBV and CBF may be correlated to patient outcome.

Conclusion: Although more data is needed, preliminary results suggest that with larger patient populations, CT perfusion may provide information that can be correlated clinically to patient outcomes. This study shows that CBF and CBV may serve as useful indicators for prognostication of TBI patients.

Traumatic brain injury and hazardous/harmful drinking: Concurrent and single associations with poor mental health and roadway aggression

This study describes the association among lifetime traumatic brain injury (TBI) and past year hazardous/harmful drinking, as well as their unique and synergistic effects, on mental health problems and roadway aggression among Canadian adults. A cross-sectional sample of 6074 Ontario adults aged 18 years or older were surveyed between 2011 and 2013. TBI was defined as trauma to the head resulting in loss of consciousness or overnight hospitalization. Past year hazardous/harmful drinking was assessed using the Alcohol Use Disorders Identification Test. An estimated 13.1% (95%CI:12.0,14.2) adults reported a prior TBI (no hazardous/harmful drinking), 2.7% (95%CI:2.2,3.3) reported a prior TBI while concurrently screening positive for past year hazardous/harmful drinking and 9.8% (95%CI:8.9,10.9) screened positive for hazardous/harmful drinking (no TBI). Men had significantly higher odds of exhibiting all three conditions compared to women, especially for the concurrent class. Younger adults had significantly greater odds of hazardous/harmful drinking, or the concurrent class compared to adults 55 years and older. Adults in any of the three conditions had greater odds for mental health problems and roadway aggression. Concordance of both conditions corresponded to a greater than additive effect and greater odds of mild roadway aggression, than either condition alone. Results show that singly and jointly, these conditions are associated with adverse health and behavioral impediments.

Disorders of carbohydrate metabolism in experimental brain injury

In experimental heavy closed brain injury (mortality infive days - 86%) it is shown that from the first hours the violations of carbohydrate metabolism in the form of triad were formed: the marked hyperglycemia (3.3-3.6 times), hyperinsulinemia (2.4-3.2 times) and insulin resistance (HOMA-indexes increased to 8.0-11.7 times). These changes were caused by a decrease in tissue sensitivity to insulin and were accompanied by decrease in functional activity of the pancreatic β-cells. In total it is possible to consider these changes as a pentad of the typical disorders of carbohydrate metabolism at brain injury.

Use of Diffusional Kurtosis Imaging and Dynamic Contrast-Enhanced MR Imaging to Predict Posttraumatic Epilepsy in Rabbits

BACKGROUND AND PURPOSE

Finding a reliable biomarker to thoroughly assess the brain structure changes in posttraumatic epilepsy is of great importance. Our aim was to explore the value of diffusional kurtosis imaging combined with dynamic contrast-enhanced MR imaging in the evaluation of posttraumatic epilepsy.

MATERIALS AND METHODS

A modified weight-drop device was used to induce traumatic brain injury. Rabbits were exposed to traumatic brain injury or sham injury. Diffusional kurtosis imaging and dynamic contrast-enhanced MR imaging were performed 1 day after injury. Posttraumatic epilepsy was investigated 3 months after injury. The traumatic brain injury group was further divided into 2 groups: the posttraumatic epilepsy and the non-posttraumatic epilepsy groups. Mean kurtosis and volume transfer coefficient values in the cortex, hippocampus, and thalamus were analyzed. After follow-up, the experimental animals were sacrificed for Nissl staining.

RESULTS

The posttraumatic epilepsy group comprised 8 rabbits. In the ipsilateral cortex, the volume transfer coefficient in the traumatic brain injury group was higher than that in the sham group; the volume transfer coefficient in the posttraumatic epilepsy group was higher than that in the non-posttraumatic epilepsy group. In the ipsilateral hippocampus, the volume transfer coefficient in the posttraumatic epilepsy group was higher than that in the non-posttraumatic epilepsy and sham groups. No difference was observed between the non-posttraumatic epilepsy and sham groups. In the ipsilateral cortex, mean kurtosis in the traumatic brain injury group was lower than that in the sham group, and mean kurtosis in the posttraumatic epilepsy group was lower than that in the non-posttraumatic epilepsy group. In the ipsilateral thalamus and hippocampus, mean kurtosis in the traumatic brain injury group was lower than that in the sham group, and mean kurtosis in the posttraumatic epilepsy group was lower than that in the non-posttraumatic epilepsy group. In the contralateral thalamus, mean kurtosis in the traumatic brain injury group was lower than that in the sham group; however, no difference was observed between the posttraumatic epilepsy and non-posttraumatic epilepsy groups.

CONCLUSIONS

Diffusional kurtosis imaging and dynamic contrast-enhanced MR imaging could be used to predict the occurrence of posttraumatic epilepsy in rabbits exposed to experimental traumatic brain injury.

Effect of Positive End-Expiratory Pressure on Optic Nerve Sheath Diameter in Pediatric Patients with Traumatic Brain Injury

Background:

The peak incidence of traumatic brain injury (TBI) has been reported in children and young adults. Intracranial pressure (ICP) as an important component can be measured with invasive technique, whereas noninvasive measurement of optic nerve sheath diameter (ONSD) is increasingly becoming popular. Positive end-expiratory pressure (PEEP) has been found to affect ICP. We aimed to compare the effect of different values of PEEP on ONSD and to obtain the correlation with ICP measurement.

Setting and Design:

Neurointensive Care Unit, Trauma Center, AIIMS, New Delhi.

Materials and Methods:

Pediatric patients with TBI, of either gender, between 1 and 18 years of age in whom ICP was measured using intraparenchymal Codman catheter admitted in neurointensive care unit were enrolled. For this crossover study, the sequence of PEEP (0 or 3 or 5 cm H₂O) was randomized and ONSD was measured. The mean of three ONSD values was taken as final value.

Statistical Method:

The ONSD, ICP, peak airway pressure, and hemodynamic parameters at various stages were compared using two-way repeated measures analysis of variance with Bonferroni correction. A P value of <0.05 was considered to be significant.

Results:

Ten patients (seven males, three females) participated in the study. There was no significant increase in ONSD values when PEEP was increased from 0 to 3 cm H₂O. However, increase in PEEP values from 3 to 5 cm H₂O showed significantly increased ONSD values.

Conclusion:

PEEP up to 3 cm H₂O can be safely applied in pediatric patients following TBI. Further increment of PEEP might accentuate the ICP values.

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.

Alterations in nitric oxide homeostasis during traumatic brain injury

Changes in nitric oxide (NO) levels have been often associated with various forms of trauma, including secondary damage after traumatic brain injury (TBI). Several studies demonstrate the upregulation of NO synthase (NOS) enzymes, and concomitant increases in brain NO levels, which contribute to the TBI-associated glutamate cytotoxicity, including the pathogenesis of mitochondrial dysfunction. TBI is also associated with elevated NO levels in remote organs, indicating that TBI can induce systemic changes in NO regulation, which can be either beneficial or detrimental. Here we review the possible mechanisms responsible for changes in NO metabolism during TBI. Better understanding of the changes in NO homeostasis in TBI will be necessary to design rational therapeutic approaches for TBI. This article is part of a Special Issue entitled: Immune and Metabolic Alterations in Trauma and Sepsis edited by Dr. Raghavan Raju.

Effects of fentanyl on pain and motor behaviors following a collagenase-induced intracerebral hemorrhage in rats

Purpose

Intracerebral hemorrhage (IH) and cephalalgia are common consequences of traumatic brain injury. One of the primary obstacles for patient recovery is the paucity of treatments to support an appropriate analgesic protocol. The present study aimed to assess pain and motor behaviors following different doses of fentanyl on a rat model of IH.

Methods

Twenty-one male Sprague Dawley rats underwent a stereotaxic surgery to produce a collagenase-induced IH in the right caudoputamen nucleus. The control group (n=6) received saline subcutaneously (SC), and experimental groups received either 5 (n=6), 10 (n=6), or 20 (n=3) µg/kg of fentanyl SC, 2 hours following surgery and on 2 subsequent days. Only 3 animals received 20 µg/kg because this dose caused catalepsy for 15–20 minutes following the injection. The rat grimace scale, a neurological examination, balance beam test, and rotarod test were performed for 5 consecutive days postoperatively to evaluate pain and motor performance. At the end of the experimentation, the brains were evaluated to determine hematoma volume, and the number of reactive astrocytes and necrotic neurons.

Results

When compared to controls, the grimace scale showed that 5 µg/kg fentanyl significantly alleviated pain on day 2 only (P<0.01) and that 10 µg/kg alleviated pain on days 1 (P<0.01), 2 (P<0.001), and 3 (P<0.01). For the rotarod test, only the 10 µg/kg group showed significant decreases in performance on days 5 (P<0.05) and 6 (P<0.02). The neurological examination was not significantly different between the groups, but only the hopping test showed poor recuperation for the 5 and 10 µg/kg fentanyl group when compared to saline (P<0.01). No differences were found between the groups for the balance beam test, the histopathological results.

Conclusion

Fentanyl, at a dose of 10 µg/kg SC, provides substantial analgesia following a collagenase-induced IH in rats; however, it can alter motor performance following analgesic treatments.

Fluid Biomarkers of Traumatic Brain Injury and Intended Context of Use

Traumatic brain injury (TBI) is one of the leading causes of death and disability around the world. The lack of validated biomarkers for TBI is a major impediment to developing effective therapies and improving clinical practice, as well as stimulating much work in this area. In this review, we focus on different settings of TBI management where blood or cerebrospinal fluid (CSF) biomarkers could be utilized for predicting clinically-relevant consequences and guiding management decisions. Requirements that the biomarker must fulfill differ based on the intended context of use (CoU). Specifically, we focus on fluid biomarkers in order to: (1) identify patients who may require acute neuroimaging (cranial computerized tomography (CT) or magnetic resonance imaging (MRI); (2) select patients at risk for secondary brain injury processes; (3) aid in counseling patients about their symptoms at discharge; (4) identify patients at risk for developing postconcussive syndrome (PCS), posttraumatic epilepsy (PTE) or chronic traumatic encephalopathy (CTE); (5) predict outcomes with respect to poor or good recovery; (6) inform counseling as to return to work (RTW) or to play. Despite significant advances already made from biomarker-based studies of TBI, there is an immediate need for further large-scale studies focused on identifying and innovating sensitive and reliable TBI biomarkers. These studies should be designed with the intended CoU in mind.

Through the looking glass: early non-invasive imaging in TBI predicts the need for interventions

Background

Early diagnosis and treatment of traumatic brain injury (TBI) lead to better outcomes. It is difficult to predict which patients benefit from specialised centres, leading to over triage or delay in definitive care. We propose that a non-invasive test comprising optic nerve sheath ultrasound, transcranial Doppler and quantitative papillary reactivity is feasible, correlates with CT findings and may allow for accurate early identification of TBI.

Methods

A 1-year, prospective observation study evaluated a low-risk, non-invasive method of assessing brain injury. Patients underwent a non-invasive neurological examination for trauma, including the above assessments. Data from the three examinations were collected within 6 hours of injury and at 24 hours, and were analysed. Demographics, haemodynamic data, imaging results and short-term outcomes/interventions were recorded.

Results

Trauma patients over the age of 18 years, with a Glascow coma scale (GCS) of <12 or CT evidence of TBI, and intubated were included (N=100). These were divided into +CT (n=49) and −CT groups (n=51) according to the Marshall CT classification of TBI. The +CT group was older, with worse GCS and higher lactate (p=0.008, p=0.001 and p=0.01) but were otherwise well matched. The +CT group included all TBI types, with 96% of the patients having more than one type of TBI. Pulsatility index and neurologic pupillary index were predictive of a +CT (p=0.04, p=0.02). Area under the receiver-operating curve for the logistic regression model for the prediction of positive radiographic findings was r=0.718. Finally, we suggest a preliminary scoring heuristic for predicting a positive radiological finding in a patient with TBI.

Conclusions

The proposed examination is a feasible, non-invasive tool that may have clinical utility in the early prediction of TBI. If validated, it may improve trauma triage for the brain-injured patient. Further studies are warranted to validate this model.

Methylene blue exerts a neuroprotective effect against traumatic brain injury by promoting autophagy and inhibiting microglial activation

Traumatic brain injury (TBI) leads to permanent neurological impairment, and methylene blue (MB) exerts central nervous system neuroprotective effects. However, only one previous study has investigated the effectiveness of MB in a controlled cortical impact injury model of TBI. In addition, the specific mechanisms underlying the effect of MB against TBI remain to be elucidated. Therefore, the present study investigated the neuroprotective effect of MB on TBI and the possible mechanisms involved. In a mouse model of TBI, the animals were randomly divided into sham, vehicle (normal saline) or MB groups. The treatment time-points were 24 and 72 h (acute phase of TBI), and 14 days (chronic phase of TBI) post-TBI. The brain water content (BWC), and levels of neuronal death, and autophagy were determined during the acute phase, and neurological deficit, injury volume and microglial activation were assessed at all time-points. The injured hemisphere BWC was significantly increased 24 h post-TBI, and this was attenuated following treatment with MB. There was a significantly higher number of surviving neurons in the MB group, compared with the Vehicle group at 24 and 72 h post-TBI. In the acute phase, the MB-treated animals exhibited significantly upregulated expression of Beclin 1 and increased LC3-II to LC3-I ratios, compared with the vehicle group, indicating an increased rate of autophagy. Neurological functional deficits, measured using the modified neurological severity score, were significantly lower in the acute phase in the MB-treated animals and cerebral lesion volumes in the MB-treated animals were significantly lower, compared with the other groups at all time-points. Microglia were activated 24 h after TBI, peaked at 72 h and persisted until 14 days after TBI. Although the number of Iba-1-positive cells in the vehicle and MB groups 24 h post-TBI were not significantly different, marked microglial inhibition was observed in the MB group 72 h and 14 days after-TBI. These results indicated that MB exerts a neuroprotective effect by increasing autophagy, decreasing brain edema and inhibiting microglial activation.

Epidemiology of traumatic brain injury in Europe

Background

Traumatic brain injury (TBI) is a critical public health and socio-economic problem throughout the world, making epidemiological monitoring of incidence, prevalence and outcome of TBI necessary. We aimed to describe the epidemiology of traumatic brain injury in Europe and to evaluate the methodology of incidence studies.

Method

We performed a systematic review and meta-analyses of articles describing the epidemiology of TBI in European countries. A search was conducted in the PubMed electronic database using the terms: epidemiology, incidence, brain injur*, head injur* and Europe. Only articles published in English and reporting on data collected in Europe between 1990 and 2014 were included.

Results

In total, 28 epidemiological studies on TBI from 16 European countries were identified in the literature. A great variation was found in case definitions and case ascertainment between studies. Falls and road traffic accidents (RTA) were the two most frequent causes of TBI, with falls being reported more frequently than RTA. In most of the studies a peak TBI incidence was seen in the oldest age groups. In the meta-analysis, an overall incidence rate of 262 per 100,000 for admitted TBI was derived.

Conclusions

Interpretation of published epidemiologic studies is confounded by differences in inclusion criteria and case ascertainment. Nevertheless, changes in epidemiological patterns are found: falls are now the most common cause of TBI, most notably in elderly patients. Improvement of the quality of standardised data collection for TBI is mandatory for reliable monitoring of epidemiological trends and to inform appropriate targeting of prevention campaigns.

Electronic supplementary material

The online version of this article (doi:10.1007/s00701-015-2512-7) contains supplementary material, which is available to authorised users.

Predicting secondary insults after severe traumatic brain injury

BACKGROUND

Secondary insults such as hypotension, hypoxia, cerebral hypoperfusion, and intracranial hypertension are associated with poor outcome following severe traumatic brain injury (TBI). Preventing and minimizing the effect of secondary insults are essential in the management of severe TBI. At present, clinicians have no way to predict the development of these events, limiting their ability to plan appropriate timing of interventions. We hypothesized that processing continuous vital signs (VS) data using machine learning methods could predict the development of future intracranial hypertension.

METHODS

Continuous VS including intracranial pressure (ICP), heart rate, systolic blood pressure, and mean arterial pressure data were collected from adult patients admitted to a single Level I trauma center requiring an ICP monitor. We tested the ability of Nearest Neighbor Regression (NNR) to predict changes in ICP by algorithmically learning from the patients' past physiology.

RESULTS

Continuous VS were collected on 132 adult patients over a minimum of 3 hours per patient (5,466 hours total; 65,600 data points). Bland-Altman plots show that NNR provides good agreement in predicting actual ICP with a bias of 0.02 (±2 SD = 4 mm Hg) for the subsequent 5 minutes and -0.02 (±2 SD = 10 mm Hg) for the subsequent 2 hours.

CONCLUSION

We have demonstrated that with the use of physiologic data, it is possible to predict with reasonable accuracy future ICP levels following severe TBI. NNR predicts ICP changes in clinically useful time frames. This ability to predict events may allow clinicians to make better decisions about the timing of necessary interventions, and this method could support the future development of minimally invasive ICP monitoring systems, which may lead to better overall clinical outcomes after severe TBI.

LEVEL OF EVIDENCE

Prognostic study, level III.

Serum substance P levels are associated with severity and mortality in patients with severe traumatic brain injury

INTRODUCTION

Substance P (SP) is a member of the tachykinin family of neuropeptides, which are widely distributed throughout the central nervous system (CNS) and actively involved in inflammatory processes. SP is released early following acute injury to the CNS, promoting a neurogenic inflammatory response characterized by an increase in the permeability of the blood-brain barrier and the development of vasogenic edema. High levels of SP could lead to an exacerbated inflammatory response that could be fatal for patients with traumatic brain injury (TBI). Thus, the main goal of the present study was to determine whether serum SP levels are associated with injury severity and mortality in patients with severe TBI.

METHODS

This multicenter, observational, prospective study was carried out in six Spanish intensive care units and included patients with Glasgow Coma Scale (GCS) scores ≤ 8. Patients with an Injury Severity Score ≥ 10 in non-cranial aspects were excluded. Blood samples were collected on day 1 of TBI to measure serum SP levels. The endpoint was 30-day mortality.

RESULTS

We found higher serum SP levels (P = 0.002) in non-surviving patients (n = 27) than in surviving patients (n = 73). The area under the curve for serum SP levels with regard to predicting 30-day mortality was 0.70 (95% confidence interval (CI), 0.60 to 0.79; P < 0.001). Survival analysis showed that patients with serum SP levels >299 pg/ml had higher 30-day mortality than patients with lower levels (hazard ratio = 3.7; 95% CI, 1.75 to 7.94; P < 0.001). Multiple binomial logistic regression analysis showed that serum SP levels >299 pg/ml were associated with 30-day mortality when we controlled for APACHE II score and Marshall computed tomography lesion classification (odds ratio (OR) = 5.97; 95% CI, 1.432 to 24.851; P = 0.01) and for GCS score and age (OR = 5.71; 95% CI, 1.461 to 22.280; P = 0.01). We found a negative association between serum SP levels and GCS score (Spearman's ρ = -0.22; P = 0.03).

CONCLUSIONS

We report, for the first time to our knowledge, that serum SP levels were associated with injury severity and mortality in patients with severe TBI. These results open the possibility that SP antagonists may be useful in the treatment of patients with severe TBI.

Temporal trends in surgical intervention for severe traumatic brain injury caused by extra-axial hemorrhage, 1995 to 2012

BACKGROUND

Surgical intervention for severe traumatic brain injury (TBI) caused by extra-axial hemorrhage has declined in recent decades. The effect of this change on patient outcomes is unknown.

OBJECTIVE

To determine the change over time in surgical intervention in this population and to assess changes in patient outcomes.

METHODS

In this retrospective cohort study, the Washington State Trauma Registry was queried from 1995 to 2012 for patients with extra-axial hemorrhage and head Abbreviated Injury Scale score of 3 to 5. Data were linked to the state-wide death registry to analyze long-term mortality. The primary outcome was inpatient mortality. Secondary outcomes included 6- and 12-month mortality and modified Functional Independence Measure at discharge. Multivariable analyses were completed for all outcomes.

RESULTS

A total of 22974 patients met inclusion criteria. Over the study period, surgical intervention for severe TBI declined from 36% to 7%. There was a decline in case fatality from 22% to 12%. In 2012, the relative risk of inpatient mortality was 23% lower compared with 1995 (adjusted mortality risk ratio, 0.77; 95% confidence interval, 0.63-0.94). Changes in 6- and 12-month adjusted mortality and modified Functional Independence Measure were not statistically significant.

CONCLUSION

The decline in surgical intervention for severe TBI caused by extra-axial hemorrhage in Washington State was ubiquitous across regional, demographic, and injury characteristic strata. There was concurrently a reduction in inpatient mortality in this population. Functional status and long-term mortality, however, have remained the same. Future studies are needed to better identify modifiable risk factors for improvement in functional status and long-term mortality in this population.

Preventable deaths in patients with traumatic brain injury

OBJECTIVE

The objective of this study is to evaluate the rate of and etiology for preventable deaths in patients with traumatic brain injuries (TBIs).

METHODS

We conducted a retrospective, multicenter review of patients with TBIs who died within 7 days of their traumatic event from June 2008 to May 2009. Three board certified emergency physicians independently reviewed every case using a structured survey format. Cases were considered preventable deaths only if all physicians independently agreed the death was preventable. Management errors contributing to the preventable death were determined.

RESULTS

Forty-one patients who died from TBI were eligible. Preventable deaths were identified in nine (22%; 95% confidence interval [CI], 11 to 28) cases. Fifty-six management errors were identified including 36 (64%; 95% CI, 50 to 77) in the emergency department and 13 (23%; 95% CI, 13 to 36) in the prehospital phase. Thirty (54%; 95% CI, 40 to 67) management errors were process-related, and 26 (46%; 95% CI, 33 to 60) were structure-related.

CONCLUSION

An important and measurable rate of preventable mortality occurs in the initial care of TBI patients. Errors were common and most occurred in the emergency department. In addition, errors were common in the prehospital phase but did not always lead to mortality. When analyzed by type of problem, both process-related and structure-related errors occurred in similar proportions.

Acute alcohol intoxication and long-term outcome in patients with traumatic brain injury

The effect of blood alcohol concentration (BAC) on outcome after traumatic brain injury (TBI) is controversial. We sought to assess the independent effect of positive BAC on long-term outcome in patients with TBI treated in the intensive care unit (ICU). We performed a retrospective analysis of 405 patients with TBI, admitted to the ICU of a large urban Level 1 trauma center between January 2009 and December 2012. Outcome was six-month mortality and unfavorable neurological outcome (defined as a Glasgow Outcome Scale score of 1 [death], 2, [vegetative state], or 3 [severe disability]). Patients were categorized by admission BAC into: no BAC (0.0‰; n=99), low BAC (<2.3‰; n=140) and high BAC (≥2.3‰; n=166). Logistic regression analysis, adjusting for baseline risk and severity of illness, was used to assess the independent effect of BAC on outcome (using the no BAC group as the reference). Overall six-month mortality was 25% and unfavorable outcome was 46%. Multivariate analysis showed low BAC to independently reduce risk of six-month mortality compared with no BAC (low BAC adjusted odds ratio [AOR] 0.41, 95% confidence interval [CI] 0.19-0.88, p=0.021) and high BAC (AOR 0.58, 95% CI 0.29-1.15, p=0.120). Furthermore, a trend towards reduced risk of six-month unfavorable neurological outcome for patients with positive BAC, compared to patients with negative BAC, was noted, although this did not reach statistical significance (low BAC AOR 0.65, 95% CI 0.34-1.22, p=0.178, and high BAC AOR 0.59, 95% CI 0.32-1.09, p=0.089). In conclusion, low admission BAC (<2.3‰) was found to independently reduce risk of six-month mortality for patients with TBI, and a trend towards improved long-term neurological outcome was found for BAC-positive patients. The role of alcohol as a neuroprotective agent warrants further studies.

Pharmacologic Treatment Reduces Pressure Times Time Dose and Relative Duration of Intracranial Hypertension

INTRODUCTION

Past work has shown the importance of the "pressure times time dose" (PTD) of intracranial hypertension (intracranial pressure [ICP] > 19 mm Hg) in predicting outcome after severe traumatic brain injury. We used automated data collection to measure the effect of common medications on the duration and dose of intracranial hypertension.

METHODS

Patients >17 years old, admitted and requiring ICP monitoring between 2008 and 2010 at a single, large urban tertiary care facility, were retrospectively enrolled. Timing and dose of ICP-directed therapy were recorded from paper and electronic medical records. The ICP data were collected automatically at 6-second intervals and averaged over 5 minutes. The percentage of time of intracranial hypertension (PTI) and PTD (mm Hg h) were calculated.

RESULTS

A total of 98 patients with 664 treatment instances were identified. Baseline PTD ranged from 27 (before administration of propofol and fentanyl) to 150 mm Hg h (before mannitol). A "small" dose of hypertonic saline (HTS; ≤250 mL 3%) reduced PTD by 38% in the first hour and 37% in the second hour and reduced the time with ICP >19 by 38% and 39% after 1 and 2 hours, respectively. A "large" dose of HTS reduced PTD by 40% in the first hour and 63% in the second (PTI reduction of 36% and 50%, respectively). An increased dose of propofol or fentanyl infusion failed to decrease PTD but reduced PTI between 14% (propofol alone) and 30% (combined increase in propofol and fentanyl, after 2 hours). Barbiturates failed to decrease PTD but decreased PTI by 30% up to 2 hours after administration. All reductions reported are significantly changed from baseline, P < .05.

CONCLUSION

Baseline PTD values before drug administration reflects varied patient criticality, with much higher values seen before the use of mannitol or barbiturates. Treatment with HTS reduced PTD and PTI burden significantly more than escalation of sedation or pain management, and this effect remained significant at 2 hours after administration.

Traumatic Brain Injury pathophysiology and treatments: early, intermediate, and late phases post-injury

Traumatic Brain Injury (TBI) affects a large proportion and extensive array of individuals in the population. While precise pathological mechanisms are lacking, the growing base of knowledge concerning TBI has put increased emphasis on its understanding and treatment. Most treatments of TBI are aimed at ameliorating secondary insults arising from the injury; these insults can be characterized with respect to time post-injury, including early, intermediate, and late pathological changes. Early pathological responses are due to energy depletion and cell death secondary to excitotoxicity, the intermediate phase is characterized by neuroinflammation and the late stage by increased susceptibility to seizures and epilepsy. Current treatments of TBI have been tailored to these distinct pathological stages with some overlap. Many prophylactic, pharmacologic, and surgical treatments are used post-TBI to halt the progression of these pathologic reactions. In the present review, we discuss the mechanisms of the pathological hallmarks of TBI and both current and novel treatments which target the respective pathways.

Risk taking in hospitalized patients with acute and severe traumatic brain injury

Rehabilitation can improve cognitive deficits observed in patients with traumatic brain injury (TBI). However, despite rehabilitation, the ability of making a choice often remains impaired. Risk taking is a daily activity involving numerous cognitive processes subserved by a complex neural network. In this work we investigated risk taking using the Balloon Analogue Risk Task (BART) in patients with acute TBI and healthy controls. We hypothesized that individuals with TBI will take less risk at the BART as compared to healthy individuals. We also predicted that within the TBI group factors such as the number of days since the injury, severity of the injury, and sites of the lesion will play a role in risk taking as assessed with the BART. Main findings revealed that participants with TBI displayed abnormally cautious risk taking at the BART as compared to healthy subjects. Moreover, healthy individuals showed increased risk taking throughout the task which is in line with previous work. However, individuals with TBI did not show this increased risk taking during the task. We also investigated the influence of three patients’ characteristics on their performance at the BART: Number of days post injury, Severity of the head injury, and Status of the frontal lobe. Results indicate that performance at the BART was influenced by the number of days post injury and the status of the frontal lobe, but not by the severity of the head injury. Reported findings are encouraging for risk taking seems to naturally improve with time postinjury. They support the need of conducting longitudinal prospective studies to ultimately identify impaired and intact cognitive skills that should be trained postinjury.

[Urgency of neurosurgical interventions for severe traumatic brain injury]

BACKGROUND

The aim of this study was to assess whether the time interval between accident and neurosurgical intervention has an influence on functional neurological outcome and mortality in severe traumatic brain injury (sTBI) or whether the further clinical course has already been determined by the initial severity of the injury.

METHODS

Data were derived from the Trauma Registry of the German Society of Trauma Surgery. A total of 770 patients were identified who had undergone decompressive surgery, had an ISS ≥ 9 and for whom time of accident and start of surgery had been documented. To evaluate the possible influence of the time factor on outcome and mortality, these patients were subdivided into five groups according to time until decompression (I: < 2 h, II: 2-3 h, III: 3-6 h, IV: 6-24 h and V: > 24 h). Aside from mortality we analysed AIS, GCS, age and ISS in survivors and non-survivors.

RESULTS

Complete data were available for 770 patients with sTBI (AIS skull ≥3). The average age was 39.9 years and 71.6% were male. The average overall injury severity was reflected by an ISS score of 31.3 and the average AIS head score was 4.51. Of the 570 who underwent surgery in less than 6 h (groups 1-III), 33% died (188/570). Of the remaining 200 patients 40 died (20%). Mortality decreased throughout the groups (49 to 14%), as did the severity of the head injury (AIS 4.66 to 4.23); GCS on the other hand increased with the time between accident and surgery (5.9 to 8.8).

CONCLUSION

We could not substantiate that reducing the time between accident and neurosurgical decompression could decrease mortality. It rather seems that the initial magnitude of brain damage determines prognosis and outcome after sTBI. The interval between the appearance of neurological symptoms (e.g. anisocoria) and neurosurgical intervention plays an important role and should be kept as short as possible.

Head trauma in China

OBJECTIVE

The Chinese Head Trauma Data Bank (CHTDB) has been established, which includes 7,145 hospitalised cases with acute head trauma patients in 47 hospitals.

METHODS

We explored factors that might affect the outcome of acute traumatic brain injury.

RESULTS

There was no statistical difference in the mortality rate between male (7.5%) and female (7.2%) patients (P>0.05). The mortality rate in children (<18 years), adults (18-65 years) and elderly (>65 years) was 7.3%, 7.2% and 9.0%, respectively (P>0.05). The mortality rate of patients with mild (2.7%), moderate (5.0%) and severe (21.8%) head trauma was significantly different (P<0.001). The mortality rate of patients with unilateral tentorial herniation, bilateral tentorial herniation and tonsillar herniation was 24.2%, 60.2% and 78.8% respectively (P<0.001). The mortality rate of patients with intracranial pressure (ICP)<20 mm Hg, 20-40 mm Hg and >40 mm Hg was 6.3%, 21.4% and 93.1%, respectively (P<0.001). The mortality rate of patients with no cerebral contusion, single cerebral contusion and multiple cerebral contusions was 3.9%, 7.8% and 14.8%, respectively (P<0.001). The mortality rate of patients with and without traumatic subarachnoid haemorrhage (tSAH) was 9.5% and 5.4%, respectively (P<0.001). The mortality rate of patients with no intracranial haematomas, single intracranial haematoma and multiple intracranial haematomas was 5.8%, 8.4% and 20.6%, respectively (P<0.001).

CONCLUSION

The CHTDB, the first head trauma data bank in China, has one of the largest numbers of cases of any head trauma data bank in the world. Our major findings on mortality may be helpful to neurosurgeons for predicting the outcome of acute head trauma patients.

Improving survival rates after civilian gunshot wounds to the brain

BACKGROUND

Gunshot wounds to the brain are the most lethal of all firearm injuries, with reported survival rates of 10% to 15%. The aim of this study was to determine outcomes in patients with gunshot wounds to the brain, presenting to our institution over time. We hypothesized that aggressive management can increase survival and the rate of organ donation in patients with gunshot wounds to the brain.

STUDY DESIGN

We analyzed all patients with gunshot wounds to the brain presenting to our level 1 trauma center over a 5-year period. Aggressive management was defined as resuscitation with blood products, hyperosmolar therapy, and/or prothrombin complex concentrate (PCC). The primary outcome was survival and the secondary outcome was organ donation.

RESULTS

There were 132 patients with gunshot wounds to the brain, and the survival rates increased incrementally every year, from 10% in 2008 to 46% in 2011, with the adoption of aggressive management. Among survivors, 40% (16 of 40) of the patients had bi-hemispheric injuries. Aggressive management with blood products (p = 0.02) and hyperosmolar therapy (p = 0.01) was independently associated with survival. Of the survivors, 20% had a Glasgow Coma Scale score ≥ 13 at hospital discharge. In patients who died (n = 92), 56% patients were eligible for organ donation, and they donated 60 organs.

CONCLUSIONS

Aggressive management is associated with significant improvement in survival and organ procurement in patients with gunshot wounds to the brain. The bias of resource use can no longer be used to preclude trauma surgeons from abandoning aggressive attempts to save patients with gunshot wound to the brain.

Patients with severe traumatic brain injury transferred to a Level I or II trauma center: United States, 2007 to 2009

BACKGROUND

Patients with severe traumatic brain injury (TBI), head Abbreviated Injury Scale (AIS) score of 3 or greater, who are indirectly transported from the scene of injury to a nontrauma center can experience delays to definitive neurosurgical management. Transport to a hospital with appropriate initial emergency department treatment and rapid admission has been shown to reduce mortality in a state's trauma system. This study was conducted to see if the same finding holds with a nationally representative sample of patients with severe TBI seen at Level I and II trauma centers.

METHODS

This study is based on adult (≥18 years), severe TBI patients treated in a nationally representative sample of Level I and II trauma centers, submitting data to the National Trauma Databank National Sample Program from 2007 to 2009. We analyzed independent variables including age, sex, primary payer, race, ethnicity, mode of transport, injury type (blunt vs. penetrating), mechanism of injury, trauma center level, head AIS, initial Glasgow Coma Scale (GCS), Injury Severity Score (ISS), and systolic blood pressure by transfer status. The primary outcome variable was inpatient death, with discharge disposition, neurosurgical procedures, and mean hospital, intensive care unit, and ventilator days serving as secondary outcomes.

RESULTS

After exclusion criteria were applied (ISS < 16; age < 18 years; GCS motor score = 6; non-head AIS score ≥ 3; head AIS < 3; patients with missing transfer status, and death on arrival), a weighted sample of 51,300 (16%) patients was eligible for analysis. In bivariate analyses, transferred patients were older (≥60 years), white, insured, less severely injured (head AIS score ≤ 4, ISS ≤ 25), and less likely to have sustained penetrating trauma (p < 0.001). After controlling for all variables, direct transport, 1 or more comorbidities, advanced age, head AIS score, intracranial hemorrhage, and firearm injury remained significant predictors of death. Being transferred (adjusted odds ratio, 0.79; 95% confidence interval, 0.64-0.96) lowered the risk of death.

CONCLUSION

Patients with severe TBI who were transferred to a Level I or II trauma center had lower injury severity, including less penetrating trauma, and, as a result, were less likely to die compared with patients who were directly admitted to a Level I or II trauma center. The results may demonstrate adherence with the current Guidelines for Prehospital Management of Traumatic Brain Injury and Guidelines for Field Triage of Injured Patients, which recommend the direct transport of patients with severe TBI to the highest level trauma center. Patients with severe TBI who cannot be taken to a trauma center should be stabilized at a nontrauma center and then transferred to a Level I or II trauma center. Regional and national trauma databases should consider collecting information on patient outcomes at referral facilities and total transport time after injury, to better address the outcomes of patient triage decisions.

LEVEL OF EVIDENCE

Prognostic study, level III; therapeutic study, level IV.

Early predictors of functional disability after spine trauma: a level 1 trauma center study

STUDY DESIGN

Retrospective review on prospective cohort and explicit chart review.

OBJECTIVE

To identify early spine trauma predictors of functional disability and to assess management compliance to established spine trauma treatment algorithms.

SUMMARY OF BACKGROUND DATA

Identification of early (within 48 hours) spine trauma predictors of functional disability is novel and may assist in the management of patients with trauma. Also, with significant global variation, spine trauma treatment algorithms are essential.

METHODS

Analysis was performed on patients with spine trauma from May 1, 2009, to January 1, 2011. Functional outcomes were determined using the Glasgow Outcome Scale (GOS) at 1 year. Univariate and multivariate regressions were applied to investigate the effects of the injury severity score, age, blood sugar level, vital signs, traumatic brain injury, comorbidities, coagulation profile, neurology, and spine injury characteristics. A compliance study was performed using the SLIC and TLICS spine trauma algorithms.

RESULTS

The completion rate for the GOS was 58.8%. The completed GOS cohort was 4.2 years younger in terms of mean age, had more number of patients with severe polytrauma, but less number of patients with severe spinal cord injuries (ASIA [American Spinal Injury Association] A, B, and C) in comparison with the uncompleted GOS cohort. Multivariate logistic regression revealed 3 independent early spine trauma predictors of functional disability with statistical significance (P < 0.05). They were (1) hypotension (OR [odds ratio] = 1.98; CI [confidence interval] = 1.13-3.49), (2) hyperglycemia (OR = 1.67; CI = 1.09-2.56), and (3) moderate/severe traumatic brain injury (OR = 5.88; CI = 1.71-20.16). There were 305 patients with subaxial cervical spine injuries and 653 patients with thoracolumbar spine injuries. The subaxial cervical spine injury classification and thoracolumbar injury classification and severity score compliance studies returned agreements of 96.1% and 98.9%, respectively.

CONCLUSION

Early independent spine trauma predictors of functional disability identified in a level 1 trauma center with high compliance to the subaxial cervical spine injury classification and thoracolumbar injury classification and severity score algorithms were hypotension, hyperglycemia, and moderate or severe traumatic brain injury. Spine trauma injury variables alone were shown not to be predictive of functional disability.

LEVEL OF EVIDENCE

3.

Novel methods to predict increased intracranial pressure during intensive care and long-term neurologic outcome after traumatic brain injury: development and validation in a multicenter dataset

OBJECTIVE

Intracranial pressure monitoring is standard of care after severe traumatic brain injury. Episodes of increased intracranial pressure are secondary injuries associated with poor outcome. We developed a model to predict increased intracranial pressure episodes 30 mins in advance, by using the dynamic characteristics of continuous intracranial pressure and mean arterial pressure monitoring. In addition, we hypothesized that performance of current models to predict long-term neurologic outcome could be substantially improved by adding dynamic characteristics of continuous intracranial pressure and mean arterial pressure monitoring during the first 24 hrs in the ICU.

DESIGN

Prognostic modeling. Noninterventional, observational, retrospective study.

SETTING AND PATIENTS

The Brain Monitoring with Information Technology dataset consisted of 264 traumatic brain injury patients admitted to 22 neuro-ICUs from 11 European countries.

INTERVENTIONS

None.

MEASUREMENTS

Predictive models were built with multivariate logistic regression and Gaussian processes, a machine learning technique. Predictive attributes were Corticosteroid Randomisation After Significant Head Injury-basic and International Mission for Prognosis and Clinical Trial design in TBI-core predictors, together with time-series summary statistics of minute-by-minute mean arterial pressure and intracranial pressure.

MAIN RESULTS

Increased intracranial pressure episodes could be predicted 30 mins ahead with good calibration (Hosmer-Lemeshow p value 0.12, calibration slope 1.02, calibration-in-the-large -0.02) and discrimination (area under the receiver operating curve = 0.87) on an external validation dataset. Models for prediction of poor neurologic outcome at six months (Glasgow Outcome Score 1-2) based only on static admission data had 0.72 area under the receiver operating curve; adding dynamic information of intracranial pressure and mean arterial pressure during the first 24 hrs increased performance to 0.90. Similarly, prediction of Glasgow Outcome Score 1-3 was improved from 0.68 to 0.87 when including dynamic information.

CONCLUSION

The dynamic information in continuous mean arterial pressure and intracranial pressure monitoring allows to accurately predict increased intracranial pressure in the neuro-ICU. Adding information of the first 24 hrs of intracranial pressure and mean arterial pressure monitoring to known baseline risk factors allows very accurate prediction of long-term neurologic outcome at 6 months.

Early predictors of mortality after spine trauma: a level 1 Australian trauma center study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To identify early independent mortality predictors after spine trauma.

SUMMARY OF BACKGROUND DATA

Spine trauma consists of spinal cord and spine column injury. The ability to identify early (within 24 hours) risk factors predictive of mortality in spine trauma has the potential to reduce mortality and improve spine trauma management.

METHODS

Analysis was performed on 215 spine column and/or spinal cord injured patients from July 2008 to August 2011. Univariate and multivariate logistic regression models were applied to investigate the effects of the Injury Severity Score, age, mechanism of injury, blood glucose level, vital signs, brain trauma severity, morbidity before trauma, coagulation profile, neurological status, and spine injuries on the risk of in-hospital death.

RESULTS

Applying a multivariate logistic regression model, there were 7 independent early predictive factors for mortality after spine injury. They were (1) Injury Severity Score more than 15 (odds ratio [OR] = 3.67; P = 0.009), (2) abnormal coagulation profile (OR = 6; P < 0.0001), (3) patients 65 years or older (OR = 3.49; P = 0.007), (4) hypotension (OR = 2.9; P = 0.033), (5) tachycardia (OR = 4.04; P = 0.005), (6) hypoxia (OR = 2.9; P = 0.033), and (7) multiple comorbidities (OR = 3.49; P = 0.007). Severe traumatic brain injury was also associated with mortality but was excluded from multivariate analysis because there were no patients with this variable in the comparison group.

CONCLUSION

Mortality predictors for spine trauma patients are similar to those for general trauma patients. Spine injury variables were shown not to be independent predictors of spine trauma mortality.

Early management of severe traumatic brain injury

Severe traumatic brain injury remains a major health-care problem worldwide. Although major progress has been made in understanding of the pathophysiology of this injury, this has not yet led to substantial improvements in outcome. In this report, we address present knowledge and its limitations, research innovations, and clinical implications. Improved outcomes for patients with severe traumatic brain injury could result from progress in pharmacological and other treatments, neural repair and regeneration, optimisation of surgical indications and techniques, and combination and individually targeted treatments. Expanded classification of traumatic brain injury and innovations in research design will underpin these advances. We are optimistic that further gains in outcome for patients with severe traumatic brain injury will be achieved in the next decade.