Effects and Clinical Characteristics of Intracranial Pressure Monitoring-Targeted Management for Subsets of Traumatic Brain Injury: An Observational Multicenter Study

Intracranial pressure monitoring for severe traumatic brain injury: A retrospective study of 273 consecutive patients

Background

Intracranial pressure (ICP) monitoring is essential in severe traumatic brain injury (sTBI) cases; yet, the frequency of high ICP occurrences remains debated. This study presents a 9-year analysis of ICP monitoring using intraventricular catheters among sTBI patients.

Methods

A retrospective review of 1760 sTBI patients (Glasgow Coma Score <9) admitted between January 2011 and December 2019 was conducted. Of these, 280 patients meeting monitoring criteria were included based on Brain Trauma Foundation (BTF) Guidelines. ICP was monitored using intraventricular catheters through right frontal burr holes. Initial ICP readings were recorded intraoperatively, followed by continuous monitoring. Patients with ICP >20 mmHg for 10-15 min during 72 h were categorized with high ICP. Data collected included demographics, computed tomography (CT) findings, intra- and post-operative ICP, and complications.

Results

Of 273 patients, 228 were male and 45 females, aged 18-80 (71.30% aged 18-45). Traffic accidents were the primary cause (90.48%). Fifty-two-point seventy-five percent experienced high ICP, correlating significantly with subdural hematoma (P < 0.001), intraventricular hemorrhage (P < 0.013), and compressed basal cisterns (P = 0.046) on initial CT. Twenty patients (7.3%) developed meningitis. Lower mortality rates and improved outcomes were observed in the low ICP group across discharge 3-and 6-month follow-ups.

Conclusion

Adherence to BTF guidelines yielded a 52.75% high ICP rate. Significant correlations were found between high ICP and specific CT abnormalities. This study underscores the benefits of ICP monitoring in selected sTBI cases, suggesting a need to review criteria for initiating monitoring protocols.

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

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

Non-Invasive Assessment of Intracranial Hypertension in Patients with Traumatic Brain Injury Using Computed Tomography Radiomic Features: A Pilot Study

This study aimed to assess intracranial hypertension in patients with traumatic brain injury non-invasively using computed tomography (CT) radiomic features. Fifty patients from the primary cohort were enrolled in this study. The clinical data, pre-operative cranial CT images, and initial intracranial pressure readings were collected and used to develop a prediction model. Data of 20 patients from another hospital were used to validate the model. Clinical features including age, sex, midline shift, basilar cistern status, and ventriculocranial ratio were measured. Radiomic features-i.e., 18 first-order and 40 second-order features- were extracted from the CT images. LASSO method was used for features filtration. Multi-variate logistic regression was used to develop three prediction models with clinical (CF model), first-order (FO model), and second-order features (SO model). The SO model achieved the most robust ability to predict intracranial hypertension. Internal validation showed that the C-statistic of the model was 0.811 (95% confidence interval [CI]: 0.691-0.931) with the bootstrapping method. The Hosmer Lemeshow test and calibration curve also showed that the SO model had excellent performance. The external validation results showed a good discrimination with an area under the curve of 0.725 (95% CI: 0.500-0.951). Although the FO model was inferior to the SO model, it had better prediction ability than the CF model. The study shows that the radiomic features analysis, especially second-order features, can be used to evaluate intracranial hypertension non-invasively compared with conventional clinical features, given its potential for clinical practice and further research.

Decompressive Hemicraniectomies as a Damage Control Approach for Multilobar Firearm Projectile Injuries: A Single-Center Experience

BACKGROUND

While firearms projectile injuries to the head carry a high rate of morbidity and mortality, current literature in clinical management remains controversial. Decompressive hemicraniectomy (DHC) has been previously described in the neurosurgical literature for traumatic brain injuries, with positive results in the reduction of mortality. Here we aim to assess DHC as a damage control approach for multilobar firearm injuries to the head and compare our results with what is present in the literature.

METHODS

A retrospective review of patients who sustained multilobar firearm injuries to the head admitted to our center from January 2009 to April 2021 was performed. Exclusion criteria were a Glasgow Coma Scale (GCS) score <5, and/or brain stem dysfunction that persisted despite stabilization and medical therapy for intracranial hypertension.

RESULTS

A total of 20 patients were analyzed, with an average GCS on admission of 8.35. The 60-day mortality rate for all 20 patients was 20% with a total of 4 deaths, 1 of which was due to pulmonary sepsis in the critical postoperative care unit. The mean hospital stay of surviving patients was 22 days.

CONCLUSIONS

DHC should be considered as a damage control strategy for young patients with multilobar firearm injuries and GCS >5, having yielded favorable results in this study when compared to current literature.

The Significance of Intracranial Pressure Monitoring for Reducing Mortality in Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

Background

Despite guidelines provided by the Brain Trauma Foundation (BTF) for treating patients with TBI, including advice to monitor intracranial pressure (ICP), the clinical application of ICP monitoring is far from universal. This laxity has been attributed to the relationship between mortality in TBI patients and ICP monitoring.

Objective

This systematic review and meta-analysis was aimed at determining the effect of intracranial pressure (ICP) monitoring on the mortality of patients with traumatic brain injury (TBI).

Method

A systematic search for articles was conducted on PubMed, Scopus, Cochrane Central Register of Control Trials (CENTRAL), and APA PsycNet for articles published from 1 January 2000 to 1 August 2022. Manager 5.4 was used to carry out statistical analysis.

Results

Article search yielded 1421 articles, but only 23 cohort studies were included in the systematic review and meta-analysis. The total number of study participants is 80,058. Seventeen studies reported unadjusted odds ratios (OR), and only 8 reported the adjusted odds ratio (OR). Nine out of seventeen studies reported an unadjusted OR of less than 1, and five out of eight studies reported an adjusted OR of less than 1. From this paper's analysis, the OR for in-hospital mortality was 1.01 [95% CI, 0.80, 1.28], with a p value of 0.92. OR for ICU mortality was 0.84 [95% CI, 0.52, 1.35], with a p value of 0.47.

Conclusion

But due to conflicting results, as evident above, it is unsatisfyingly challenging to draw any substantial conclusions from them. This paper thus calls for more research on this particular paper.

Brain Tissue Damage Induced by Multimodal Neuromonitoring In Situ during MRI after Severe Traumatic Brain Injury: Incidence and Clinical Relevance

Both neuromonitoring and early magnetic resonance imaging (MRI) provide crucial information for treatment management and prognosis in patients with severe traumatic brain injury (sTBI). So far, neuromonitoring in situ impedes the routine implementation of MRI due to safety concerns. We aimed to evaluate the brain tissue damage induced by inserted neuromonitoring devices and its clinical relevance. Nineteen patients with sTBI and being exposed to at least one MRI with neuromonitoring in situ and one follow-up MRI after neuromonitoring removal were analyzed. All MRIs were reviewed for specific tissue damage. Three females and sixteen males (aged 20–74 years, mean 42.8 years) with an initial median GCS of 5 (range 3–8) were analyzed. No lesion was observed in six patients (31.6%), whereas another six patients (31.6%) demonstrated a detectable probe trajectory. Probe-related tissue damage was visible in seven patients (36.8%) with the size of the lesion prone to further enlarge with increasing cumulative duration of MRI examinations. Upon interdisciplinary evaluation, the lesions were not considered clinically relevant. Neuromonitoring probes in situ during MRI examinations may cause local brain tissue damage, yet without any clinical implications if placed correctly. Therefore, indications must be strictly based on joint decision from all involved disciplines.

Intracranial Pressure Monitoring in Moderate Traumatic Brain Injury: A Systematic Review and Meta-Analysis

BACKGROUND

The principal aim of this study was to determine the prevalence of intracranial pressure (ICP) monitoring and intracranial hypertension (IHT) in patients treated for moderate traumatic brain injury (TBI). A secondary objective was to assess factors associated with ICP monitoring.

METHODS

We conducted a systematic review of the literature to identify studies that assessed ICP monitoring in moderate TBI. The meta-analysis was performed by using a random-effects model.

RESULTS

A total of 13 studies comprising 116,714 patients were pooled to estimate the overall prevalence of ICP monitoring and IHT (one episode or more of ICP > 20 mm Hg) after moderate TBI. The prevalence rate for ICP monitoring was 18.3% (95% confidence interval 8.1-36.1%), whereas the proportion of IHT was 44% (95% confidence interval 33.8-54.7%). Three studies were pooled to estimate the prevalence of ICP monitoring according to Glasgow Coma Scale (GCS) (≤ 10 vs. > 10). ICP monitoring was performed in 32.2% of patients with GCS ≤ 10 versus 15.2% of patients with GCS > 10 (p = 0.59). Both subgroups were highly heterogeneous. We found no other variables associated with ICP monitoring or IHT.

CONCLUSIONS

The prevalence of ICP monitoring in moderate TBI is low, but the prevalence of IHT is high among patients undergoing ICP monitoring. Current literature is limited in size and quality and does not identify factors associated with ICP monitoring or IHT. Further research is needed to guide the optimal use of ICP monitoring in moderate TBI.

Intracranial Pressure Monitoring in the Intensive Care Unit for Patients with Severe Traumatic Brain Injury: Analysis of the CENTER-TBI China Registry

BACKGROUND

Although the current guidelines recommend the use of intracranial pressure (ICP) monitoring in patients with severe traumatic brain injury (sTBI), the evidence indicating benefit is limited. The present study aims to evaluate the impact of ICP monitoring on patients with sTBI in the intensive care unit (ICU).

METHODS

The patient data were obtained from the Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury China Registry, a prospective, multicenter, longitudinal, observational, cohort study. Patients with sTBI who were admitted to 52 ICUs across China, managed with ICP monitoring or without, were analyzed in this study. Patients with missing information on discharge survival status, Glasgow Coma Scale score on admission to hospital, and record of ICP monitoring application were excluded from the analysis. Data on demographic characteristics, injury, clinical features, treatments, survival at discharge, discharge destination, and length of stay were collected and assessed. The primary end point was survival state at discharge, and death from any cause was considered the event of interest.

RESULTS

A total of 2029 patients with sTBI were admitted to the ICU; 737 patients (36.32%) underwent ICP monitoring, and 1292 (63.68%) were managed without ICP monitoring. There was a difference between management with and without ICP monitoring on in-hospital mortality in the unmatched cohort (18.86% vs. 26.63%, p < 0.001) and the propensity-score-matched cohort (19.82% vs. 26.83%, p = 0.003). Multivariate logistic regressions also indicated that increasing age, higher injury severity score, lower Glasgow Coma Scale score, unilateral and bilateral pupillary abnormalities, systemic hypotension (SBP ≤ 90 mm Hg), hypoxia (SpO2 < 95%) on arrival at the hospital, and management without ICP monitoring were associated with higher in-hospital mortality. However, the patients without ICP monitoring had a lower length of stay in the ICU (11.79 vs. 7.95 days, p < 0.001) and hospital (25.96 vs. 21.71 days, p < 0.001), and a higher proportion of survivors were discharged to the home with better recovery in self-care.

CONCLUSIONS

Although ICP monitoring was not widely used by all of the centers participating in this study, patients with sTBI managed with ICP monitoring show a better outcome in overall survival. Nevertheless, the use of ICP monitoring makes the management of sTBI more complex and increases the costs of medical care by prolonging the patient's stay in the ICU or hospital.

Intracranial pressure monitoring following traumatic brain injury: evaluation of indications, complications, and significance of follow-up imaging-an exploratory, retrospective study of consecutive patients at a level I trauma center

Background

Measurement of intracranial pressure (ICP) is an essential part of clinical management of severe traumatic brain injury (TBI). However, clinical utility and impact on clinical outcome of ICP monitoring remain controversial. Follow-up imaging using cranial computed tomography (CCT) is commonly performed in these patients. This retrospective cohort study reports on complication rates of ICP measurement in severe TBI patients, as well as on findings and clinical consequences of follow-up CCT.

Methods

We performed a retrospective clinical chart review of severe TBI patients with invasive ICP measurement treated at an urban level I trauma center between January 2007 and September 2017.

Results

Clinical records of 213 patients were analyzed. The mean Glasgow Coma Scale (GCS) on admission was 6 with an intra-hospital mortality of 20.7%. Overall, complications in 12 patients (5.6%) related to the invasive ICP-measurement were recorded of which 5 necessitated surgical intervention. Follow-up CCT scans were performed in 192 patients (89.7%). Indications for follow-up CCTs included routine imaging without clinical deterioration (n = 137, 64.3%), and increased ICP values and/or clinical deterioration (n = 55, 25.8%). Follow-up imaging based on clinical deterioration and increased ICP values were associated with significantly increased likelihoods of worsening of CCT findings compared to routinely performed CCT scans with an odds ratio of 5.524 (95% CI 1.625–18.773) and 6.977 (95% CI 3.262–14.926), respectively. Readings of follow-up CCT imaging resulted in subsequent surgical intervention in six patients (3.1%).

Conclusions

Invasive ICP-monitoring in severe TBI patients was safe in our study population with an acceptable complication rate. We found a high number of follow-up CCT. Our results indicate that CCT imaging in patients with invasive ICP monitoring should only be considered in patients with elevated ICP values and/or clinical deterioration.

Intracranial Pressure Monitoring-Aided Management Associated with Favorable Outcomes in Patients with Hypertension-Related Spontaneous Intracerebral Hemorrhage

To investigate the effect of intracranial pressure (ICP) monitoring on the functional outcome of patients with hypertension-related spontaneous intracerebral hemorrhage (ICH). We included 196 patients with Glasgow Coma Scale (GCS) scores of 3-12 in this observational study, of which 103 underwent ICP monitors. Binary and ordinal regression analyses were used to estimate the effect of ICP monitoring on the functional outcome. The rate of adverse events, blood pressure control, and length of hospitalization were compared between the two groups. ICP monitoring had a significant impact on the clinical outcome of patients by shifting the Extended Glasgow Outcome Scale (GOS-E) scores in a favorable direction (p = 0.027) and reducing mortality at discharge (p = 0.004) and 6 months later (p = 0.02). The rate of favorable outcome at 6 months was higher in the ICP-monitored group (p = 0.03). However, subgroup analysis showed that no relationship between ICP monitoring and clinical outcome was found for patients with GCS scores of 3-8. For patients with GCS scores of 9-12, the distribution of GOS-E scores at 6 months shifted in a favorable direction in the ICP-monitored group (p = 0.001). The rate of favorable outcome at 6 months was higher in the ICP-monitored group (p = 0.01). The mortality at discharge and 6 months later was also lower in the ICP-monitored group. Thus, our study supports the value of ICP monitoring in hypertension-related ICH patients with GCS scores of 3-12, especially those with GCS scores of 9-12.

First Intracranial Pressure Monitoring or First Operation: Which One Is Better?

BACKGROUND

For patients with TBI, traditional methods such as clinical examination and imaging data are the primary references used for deciding whether to operate or not. Intracranial pressure (ICP) monitoring based on lateral ventricles or parenchymal pressure is a more direct reflection of ICP. However, the research on whether the outcome results of ICP monitoring are better than results based on clinical signs and imaging is sparse. Therefore, we compared treatment results for patients with TBI based on ICP monitoring and traditional methods.

METHODS

This retrospective study included patients with TBI admitted to our collaborative hospitals between January 1, 2012, and December 31, 2013. All patients enrolled were divided into a traditional methods group and ICP monitoring group. Follow-up treatment was determined by ICP monitoring value or traditional methods in the 2 groups. Propensity matching scores were used to ensure that baseline characteristics of patients in the 2 groups were consistent.

RESULTS

A significant association was found between the initial ICP value and neurologic deterioration (odds ratio 1.24; P < 0.001), and nonlinear correlation achieved the best fit (R² = 0.547). Both 6-month good recovery rate and favorable outcome rate were higher in the ICP monitoring group than the traditional methods group by propensity score analysis (P < 0.05).

CONCLUSIONS

For patients with TBI with cerebral contusion volume >20 mL, both 6-month good recovery rate and favorable outcome rate were significantly higher in the ICP monitoring group than the traditional methods group.

The Value of Managing Severe Traumatic Brain Injury During the Perioperative Period Using Intracranial Pressure Monitoring

This study aimed to investigate the clinical efficacy of intracranial pressure (ICP) monitoring regarding the perioperative management of patients with severe traumatic brain injury (sTBI). This was a cohort study performed between Jan 2013 and Jan 2016 and included all patients with sTBI. All patients were split into ICP monitoring and non-ICP monitoring groups. The primary outcomes were in-hospital mortality and Glasgow Outcome Scale (GOS) scores 6 months after injury, whereas the secondary outcomes include rate of successful nonsurgical treatment, rate of decompression craniotomy (DC), the length of stay in the ICU, and the hospital and medical expenses. This retrospective analysis included 246 ICP monitoring sTBI patients and 695 without ICP monitoring sTBI patients. No significant difference between groups regarding patient demographics. All patients underwent a GOS assessment 6 months after surgery. Compared to the non-ICP monitoring group, a lower in-hospital mortality (20.3% vs 30.2%, P < 0.01) and better GOS scores after 6 months (3.3 ± 1.6 vs 2.9 ± 1.6, P < 0.05) with ICP monitoring. In addition, patients in the ICP monitoring group had a lower craniotomy rate (41.1% vs 50.9%, P < 0.01) and a lower DC rate (41.6% vs 55.9%, P < 0.05) than those in the non-ICP monitoring group. ICU length of stay (12.4 ± 4.0 days vs 10.2 ± 4.8 days, P < 0.01) was shorter in the non-ICP monitoring group, but it had no difference between 2 groups on total length of hospital stay (22.9 ± 13.6 days vs 24.6 ± 13.6 days, P = 0.108); Furthermore, the medical expenses were significantly higher in the non-ICP monitoring group than the ICP monitoring group (11.5 ± 7.2 vs 13.3 ± 9.1, P < 0.01). Intracranial pressure monitoring has beneficial effects for sTBI during the perioperative period. It can reduce the in-hospital mortality and DC rate and also can improve the 6-month outcomes. However, this was a single institution and observational study, well-designed, multicenter, randomized control trials are needed to evaluate the effects of ICP monitoring for perioperative sTBI patients.

Traumatic brain injury in China

China has more patients with traumatic brain injury (TBI) than most other countries in the world, making this condition a major public health concern. Population-based mortality of TBI in China is estimated to be approximately 13 cases per 100 000 people, which is similar to the rates reported in other countries. The implementation of various measures, such as safety legislation for road traffic, establishment of specialised neurosurgical intensive care units, and the development of evidence-based guidelines, have contributed to advancing prevention and care of patients with TBI in China. However, many challenges remain, which are augmented further by regional differences in TBI care. High-level care, such as intracranial pressure monitoring, is not universally available yet. In the past 30 years, the quality of TBI research in China has substantially improved, as evidenced by an increasing number of clinical trials done. The large number of patients with TBI and specialised trauma centres offer unique opportunities for TBI research in China. Furthermore, the formation and development of research collaborations between China and international groups are considered essential to advancing the quality of TBI care and research in China, and to improve quality of life in patients with this condition.

Twenty-Five Years of Intracranial Pressure Monitoring After Severe Traumatic Brain Injury: A Retrospective, Single-Center Analysis

BACKGROUND

Intracranial pressure (ICP) is a clinically important variable after severe traumatic brain injury (TBI) and has been monitored, along with clinical outcome, for over 25 yr in Addenbrooke's hospital, Cambridge, United Kingdom. This time period has also seen changes in management strategies with the implementation of protocolled specialist neurocritical care, expansion of neuromonitoring techniques, and adjustments of clinical treatment targets.

OBJECTIVE

To describe the changes in intracranial monitoring variables over the past 25 yr.

METHODS

Data from 1146 TBI patients requiring ICP monitoring were analyzed. Monitored variables included ICP, cerebral perfusion pressure (CPP), and the cerebral pressure reactivity index (PRx). Data were stratified into 5-yr epochs spanning the 25 yr from 1992 to 2017.

RESULTS

CPP increased sharply with specialist neurocritical care management (P &lt; 0.0001) (introduction of a specific TBI management algorithm) before stabilizing from 2000 onwards. ICP decreased significantly over the 25 yr of monitoring from an average of 19 to 12 mmHg (P &lt; 0.0001) but PRx remained unchanged. The mean number of ICP plateau waves and the number of patients developing refractory intracranial hypertension both decreased significantly. Mortality did not significantly change in the cohort (22%).

CONCLUSION

We demonstrate the evolving trends in neurophysiological monitoring over the past 25 yr from a single, academic neurocritical care unit. ICP and CPP were responsive to the introduction of an ICP/CPP protocol while PRx has remained unchanged.

Comparing Plasma Phospho Tau, Total Tau, and Phospho Tau-Total Tau Ratio as Acute and Chronic Traumatic Brain Injury Biomarkers

Importance

Annually in the United States, at least 3.5 million people seek medical attention for traumatic brain injury (TBI). The development of therapies for TBI is limited by the absence of diagnostic and prognostic biomarkers. Microtubule-associated protein tau is an axonal phosphoprotein. To date, the presence of the hypophosphorylated tau protein (P-tau) in plasma from patients with acute TBI and chronic TBI has not been investigated.

Objective

To examine the associations between plasma P-tau and total-tau (T-tau) levels and injury presence, severity, type of pathoanatomic lesion (neuroimaging), and patient outcomes in acute and chronic TBI.

Design, Setting, and Participants

In the TRACK-TBI Pilot study, plasma was collected at a single time point from 196 patients with acute TBI admitted to 3 level I trauma centers (<24 hours after injury) and 21 patients with TBI admitted to inpatient rehabilitation units (mean [SD], 176.4 [44.5] days after injury). Control samples were purchased from a commercial vendor. The TRACK-TBI Pilot study was conducted from April 1, 2010, to June 30, 2012. Data analysis for the current investigation was performed from August 1, 2015, to March 13, 2017.

Main Outcomes and Measures

Plasma samples were assayed for P-tau (using an antibody that specifically recognizes phosphothreonine-231) and T-tau using ultra-high sensitivity laser-based immunoassay multi-arrayed fiberoptics conjugated with rolling circle amplification.

Results

In the 217 patients with TBI, 161 (74.2%) were men; mean (SD) age was 42.5 (18.1) years. The P-tau and T-tau levels and P-tau-T-tau ratio in patients with acute TBI were higher than those in healthy controls. Receiver operating characteristic analysis for the 3 tau indices demonstrated accuracy with area under the curve (AUC) of 1.000, 0.916, and 1.000, respectively, for discriminating mild TBI (Glasgow Coma Scale [GCS] score, 13-15, n = 162) from healthy controls. The P-tau level and P-tau-T-tau ratio were higher in individuals with more severe TBI (GCS, ≤12 vs 13-15). The P-tau level and P-tau-T-tau ratio outperformed the T-tau level in distinguishing cranial computed tomography-positive from -negative cases (AUC = 0.921, 0.923, and 0.646, respectively). Acute P-tau levels and P-tau-T-tau ratio weakly distinguished patients with TBI who had good outcomes (Glasgow Outcome Scale-Extended GOS-E, 7-8) (AUC = 0.663 and 0.658, respectively) and identified those with poor outcomes (GOS-E, ≤4 vs >4) (AUC = 0.771 and 0.777, respectively). Plasma samples from patients with chronic TBI also showed elevated P-tau levels and a P-tau-T-tau ratio significantly higher than that of healthy controls, with both P-tau indices strongly discriminating patients with chronic TBI from healthy controls (AUC = 1.000 and 0.963, respectively).

Conclusions and Relevance

Plasma P-tau levels and P-tau-T-tau ratio outperformed T-tau level as diagnostic and prognostic biomarkers for acute TBI. Compared with T-tau levels alone, P-tau levels and P-tau-T-tau ratios show more robust and sustained elevations among patients with chronic TBI.

Dramatic increases in blood glutamate concentrations are closely related to traumatic brain injury-induced acute lung injury

Traumatic brain injury-induced acute lung injury (TBI-ALI) is a serious complication after brain injury for which predictive factors are lacking. In this study, we found significantly elevated blood glutamate concentrations in patients with TBI or multiple peripheral trauma (MPT), and patients with more severe injuries showed higher blood glutamate concentrations and longer durations of elevated levels. Although the increase in amplitude was similar between the two groups, the duration was longer in the patients with TBI. There were no significant differences in blood glutamate concentrations in the patients with MPT with regard to ALI status, but the blood glutamate levels were significantly higher in the patients with TBI-ALI than in those without ALI. Moreover, compared to patients without ALI, patients with TBI showed a clearly enhanced inflammatory response that was closely correlated with the blood glutamate levels. The blood glutamate concentration was also found to be a risk factor (adjusted odds ratio, 2.229; 95% CI, 1.082–2.634) and was a better predictor of TBI-ALI than the Glasgow Coma Scale (GCS) score. These results indicated that dramatically increased blood glutamate concentrations were closely related to the occurrence of TBI-ALI and could be used as a predictive marker for “at-risk” patients.

Effects of Intracranial Pressure Monitoring on Mortality in Patients with Severe Traumatic Brain Injury: A Meta-Analysis

BACKGROUND

The Brain Trauma Foundation (BTF) guidelines published in 2007 suggest some indications for intracranial pressure (ICP) monitoring in severe traumatic brain injury (TBI). However, some studies had not shown clinical benefit in patients with severe TBI; several studies had even reported that ICP monitoring was associated with an increased mortality rate. The effect of ICP monitoring has remained controversial, regardless of the ICP monitoring guidelines. Here we performed a meta-analysis of published studies to assess the effects of ICP monitoring in patients with severe TBI.

METHODS

We searched three comprehensive databases, the Cochrane Library, PUBMED, and EMBASE, for studies without limitations published up to September 2015. Mortality, ICU LOS, and hospital LOS were analyzed with Review Manager software according to data from the included studies.

RESULTS

Eighteen eligible studies involving 25229 patients with severe TBI were included in our meta-analysis. The results indicated no significant reduction in the ICP monitored group in mortality (hospitalized before 2007), hospital mortality (hospitalized before 2007), mortality in randomized controlled trials. However, overall mortality, mortality (hospitalized after 2007), hospital mortality (hospitalized after 2007), mortality in observational studies (hospitalized after 2007), 2-week mortality, 6-month mortality, were reduced in ICP monitored group. Patients with an increased ICP were more likely to require ICP monitoring.

CONCLUSION

Superior survival was observed in severe TBI patients with ICP monitoring since the third edition of "Guidelines for the Management of Severe Traumatic Brain Injury," which included "Indications for intracranial pressure monitoring," was published in 2007.

Intraventricular intracranial pressure monitoring improves the outcome of older adults with severe traumatic brain injury: an observational, prospective study

BACKGROUND

Intracranial pressure (ICP) monitoring is widely used in the management of patients with severe traumatic brain injury (TBI). However, there is limited evidence about the efficacy of ICP monitoring in older subjects (aged ≥65 years). This study evaluated the effect of intraventricular ICP monitoring on the outcome of older adults suffering from a severe TBI.

METHODS

This prospective, observational study included 166 older TBI patients (aged ≥65 years) with Glasgow Coma scale (GCS) scores lower than 9 at admission. The study cohort was divided into two groups, intraventricular ICP monitoring and non-ICP monitoring. The primary outcome was in-hospital mortality. The secondary outcomes included the Glasgow Outcome Scale (GOS) score 6 months after injury, the ICU and total hospital lengths of stay, and mechanical ventilation days.

RESULTS

There were 80 patients in the intraventricular ICP monitoring group and 86 patients in non-ICP monitoring group. There was no statistical difference between groups in demographics and severity of head injury. Patients treated with intraventricular ICP monitoring had lower in-hospital mortality (33.8 % vs 51.2 %, P < 0.05), a higher 6-month GOS score (3.0 ± 1.4 vs 2.5 ± 1.2 P < 0.05), and a lower dosage (514 ± 246 g vs 840 ± 323 g, P < 0.0001) and shorter duration (7.2 ± 3.6 days vs 8.4 ± 4.3 days, P < 0.01) of mannitol use. However, the ICU length of stay (14.3 ± 6.4 days vs 11.6 ± 5.8 days, P < 0.01) and mechanical ventilation days (6.7 ± 3.5 days vs 5.6 ± 2.4 days, P < 0.05) were longer in the ICP monitoring group. The total length of hospital stay did not differ between the two groups (28.5 ± 12.1 days vs 26.1 ± 13.5 days, P = 0.23).

CONCLUSIONS

Intraventricular ICP monitoring may have beneficial effects on the decreased in-hospital mortality and improved 6-month outcome of older patients with severe TBI. However, given that this was an observational study conducted in a single institution, further well-designed randomized control trials are needed to evaluate the effect of intraventricular ICP monitoring on the outcome of older severe TBI patients.