Clinical Epidemiology of Adults With Moderate Traumatic Brain Injury

PaCO2 Association with Outcomes of Patients with Traumatic Brain Injury at High Altitude: A Prospective Single-Center Cohort Study

BACKGROUND

Partial pressure of carbon dioxide (PaCO2) is generally known to influence outcome in patients with traumatic brain injury (TBI) at normal altitudes. Less is known about specific relationships of PaCO2 levels and clinical outcomes at high altitudes.

METHODS

This is a prospective single-center cohort of consecutive patients with TBI admitted to a trauma center located at 2600 m above sea level. An unfavorable outcome was defined as a Glasgow Outcome Scale-Extended (GOSE) score < 4 at the 6-month follow-up.

RESULTS

We had a total of 81 patients with complete data, 80% (65/81) were men, and the median (interquartile range) age was 36 (25-50) years. Median Glasgow Coma Scale (GCS) score on admission was 9 (6-14); 49% (40/81) of patients had severe TBI (GCS 3-8), 32% (26/81) had moderate TBI (GCS 12-9), and 18% (15/81) had mild TBI (GCS 13-15). The median (interquartile range) Abbreviated Injury Score of the head (AISh) was 3 (2-4). The frequency of an unfavorable outcome (GOSE < 4) was 30% (25/81), the median GOSE was 4 (2-5), and the median 6-month mortality rate was 24% (20/81). Comparison between patients with favorable and unfavorable outcomes revealed that those with unfavorable outcome were older, (median age 49 [30-72] vs. 29 [22-41] years, P < 0.01), had lower admission GCS scores (6 [4-8] vs. 13 [8-15], P < 0.01), had higher AISh scores (4 [4-4] vs. 3 [2-4], P < 0.01), had higher Acute Physiology and Chronic Health disease Classification System II scores (17 [15-23] vs. 10 [6-14], P < 0.01), had higher Charlson scores (0 [0-2] vs. 0 [0-0], P < 0.01), and had higher PaCO2 levels (mean 35 ± 8 vs. 32 ± 6 mm Hg, P < 0.01). In a multivariate analysis, age (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.1-1.30, P < 0.01), AISh (OR 4.7, 95% CI 1.55-21.0, P < 0.05), and PaCO2 levels (OR 1.23, 95% CI 1.10-1.53, P < 0.05) were significantly associated with the unfavorable outcomes. When applying the same analysis to the subgroup on mechanical ventilation, AISh (OR 5.4, 95% CI 1.61-28.5, P = 0.017) and PaCO2 levels (OR 1.36, 95% CI 1.13-1.78, P = 0.015) remained significantly associated with the unfavorable outcome.

CONCLUSIONS

Higher PaCO2 levels are associated with an unfavorable outcome in ventilated patients with TBI. These results underscore the importance of PaCO2 levels in patients with TBI and whether it should be adjusted for populations living at higher altitudes.

Rosiglitazone regulates astrocyte polarization and neuroinflammation in a PPAR-γ dependent manner after experimental traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of high mortality and disability worldwide. Overactivation of astrocytes and overexpression of inflammatory responses in the injured brain are characteristic pathological features of TBI. Rosiglitazone (ROS) is a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist known for its anti-inflammatory activity. However, the relationship between the inflammatory response involved in ROS treatment and astrocyte A1 polarization remains unclear.

OBJECTIVE

This study aimed to investigate whether ROS treatment improves dysfunction and astrocyte A1 polarization induced after TBI and to elucidate the underlying mechanisms of these functions.

METHODS

SD rats were randomly divided into sham operation group, TBI group, TBI+ROS group, and TBI+ PPAR-γ antagonist group (GW9662 + TBI). The rat TBI injury model was prepared by the CCI method; brain water content test and wire grip test scores suggested the prognosis; FJB staining showed the changes of ROS on the morphology and number of neurons in the peripheral area of cortical injury; ELISA, immunofluorescence staining, and western blotting analysis revealed the effects of ROS on inflammatory response and astrocyte activation with the degree of A1 polarization after TBI.

RESULTS

Brain water content, inflammatory factor expression, and astrocyte activation in the TBI group were higher than those in the sham-operated group (P < 0.05); compared with the TBI group, the expression of the above indexes in the ROS group was significantly lower (P < 0.05). Compared with the TBI group, PPAR-γ content was significantly higher and C3 content was considerably lower in the ROS group (P < 0.05); compared with the TBI group, PPAR-γ content was significantly lower and C3 content was substantially higher in the inhibitor group (P < 0.05).

CONCLUSION

ROS can exert neuroprotective effects by inhibiting astrocyte A1 polarization through the PPAR-γ pathway based on the reduction of inflammatory factors and astrocyte activation in the brain after TBI.

Guidelines for Neuroprognostication in Critically Ill Adults with Moderate-Severe Traumatic Brain Injury

BACKGROUND

Moderate-severe traumatic brain injury (msTBI) carries high morbidity and mortality worldwide. Accurate neuroprognostication is essential in guiding clinical decisions, including patient triage and transition to comfort measures. Here we provide recommendations regarding the reliability of major clinical predictors and prediction models commonly used in msTBI neuroprognostication, guiding clinicians in counseling surrogate decision-makers.

METHODS

Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology, we conducted a systematic narrative review of the most clinically relevant predictors and prediction models cited in the literature. The review involved framing specific population/intervention/comparator/outcome/timing/setting (PICOTS) questions and employing stringent full-text screening criteria to examine the literature, focusing on four GRADE criteria: quality of evidence, desirability of outcomes, values and preferences, and resource use. Moreover, good practice recommendations addressing the key principles of neuroprognostication were drafted.

RESULTS

After screening 8125 articles, 41 met our eligibility criteria. Ten clinical variables and nine grading scales were selected. Many articles varied in defining "poor" functional outcomes. For consistency, we treated "poor" as "unfavorable". Although many clinical variables are associated with poor outcome in msTBI, only the presence of bilateral pupillary nonreactivity on admission, conditional on accurate assessment without confounding from medications or injuries, was deemed moderately reliable for counseling surrogates regarding 6-month functional outcomes or in-hospital mortality. In terms of prediction models, the Corticosteroid Randomization After Significant Head Injury (CRASH)-basic, CRASH-CT (CRASH-basic extended by computed tomography features), International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT)-core, IMPACT-extended, and IMPACT-lab models were recommended as moderately reliable in predicting 14-day to 6-month mortality and functional outcomes at 6 months and beyond. When using "moderately reliable" predictors or prediction models, the clinician must acknowledge "substantial" uncertainty in the prognosis.

CONCLUSIONS

These guidelines provide recommendations to clinicians on the formal reliability of individual predictors and prediction models of poor outcome when counseling surrogates of patients with msTBI and suggest broad principles of neuroprognostication.

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.

PaCO2 Association with Traumatic Brain Injury Patients Outcomes at High Altitude: A Prospective Single-Center Cohort Study

Background

partial pressure of carbon dioxide (PaCO2) is generally known to influence outcome in patients with traumatic brain injury (TBI) at normal altitudes. Less is known about specific relationships of PaCO2 levels and clinical outcomes at high altitudes.

Methods

This is a prospective single-center cohort of consecutive TBI patients admitted to a trauma center located at 2600 meter above sea level. An unfavorable outcome was defined as the Glasgow Outcome Scale-Extended (GOSE) < 4 at 6-month follow-up.

Results

81 patients with complete data, 80% (65/81) were men, and median (IQR) age was 36 (25-50) years). Median Glasgow Coma Scale (GCS) on admission was 9 (6-14), 49% (40/81) were severe (GCS: 3-8), 32% (26/81) moderate (GCS 12 - 9), and 18% (15/81) mild (GCS 13-15) TBI. The median (IQR) Abbreviated Injury Score of the Head (AISh) was 3 (2-4). Frequency of an unfavorable outcome (GOSE < 4) was 30% (25/81), median GOSE was 4 (2-5), and 6-month mortality was 24% (20/81). Comparison between patients with favorable and unfavorable outcomes revealed that those with unfavorable outcome were older, median [49 (30-72) vs. 29 (22-41), P < 0.01], had lower admission GCS [6 (4-8) vs. 13 (8-15), P < 0.01], higher AIS head [4 (4-4) vs. 3(2-4), p < 0.01], higher APACHE II score [17(15-23) vs 10 (6-14), < 0.01), higher Charlson score [0(0-2) vs. 0 (0-0), P < 0.01] and higher PaCO2 (mmHg), mean ± SD, 39 ± 9 vs. 32 ± 6, P < 0.01. In a multivariate analysis, age (OR 1.14 95% CI 1.1-1.30, P < 0.01), AISh (OR 4.7 95% CI 1.55-21.0, P < 0.05), and PaCO2 (OR 1.23 95% CI: 1.10-1.53, P < 0.05) were significantly associated with the unfavorable outcomes. When applying the same analysis to the subgroup on mechanical ventilation, AISh (OR 5.4 95% CI: 1.61-28.5, P = 0.017) and PaCO2 (OR 1.36 95% CI: 1.13-1.78, P = 0.015) remained significantly associated with the unfavorable outcome.

Conclusion

Higher PaCO2 levels are associated with an unfavorable outcome in ventilated TBI patients. These results underscore the importance of PaCO2 level in TBI patients and whether it should be adjusted for populations living at higher altitudes.

Secondary Neurologic Deterioration After Moderate Traumatic Brain Injury: Development of a Multivariable Prediction Model and Proposition of a Simple Triage Score

BACKGROUND

Identifying patients at risk of secondary neurologic deterioration (SND) after moderate traumatic brain injury (moTBI) is a challenge, as such patients will need specific care. No simple scoring system has been evaluated to date. This study aimed to determine clinical and radiological factors associated with SND after moTBI and to propose a triage score.

METHODS

All adults admitted in our academic trauma center between January 2016 and January 2019 for moTBI (Glasgow Coma Scale [GCS] score, 9-13) were eligible. SND during the first week was defined either by a decrease in GCS score of >2 points from the admission GCS in the absence of pharmacologic sedation or by a deterioration in neurologic status associated with an intervention, such as mechanical ventilation, sedation, osmotherapy, transfer to the intensive care unit (ICU), or neurosurgical intervention (for intracranial mass lesions or depressed skull fracture). Clinical, biological, and radiological independent predictors of SND were identified by logistic regression (LR). An internal validation was performed using a bootstrap technique. A weighted score was defined based on beta (β) coefficients of the LR.

RESULTS

A total of 142 patients were included. Forty-six patients (32%) showed SND, and 14-day mortality rate was 18.4%. Independent variables associated with SND were age above 60 years (odds ratio [OR], 3.45 [95% confidence interval {CI}, 1.45-8.48]; P = .005), brain frontal contusion (OR, 3.22 [95% CI, 1.31-8.49]; P = .01), prehospital or admission arterial hypotension (OR, 4.86 [95% CI, 2.03-12.60]; P = .006), and a Marshall computed tomography (CT) score of 6 (OR, 3.25 [95% CI, 1.31-8.20]; P = .01). The SND score was defined with a range from 0 to 10. The score included the following variables: age >60 years (3 points), prehospital or admission arterial hypotension (3 points), frontal contusion (2 points), and Marshall CT score of 6 (2 points). The score was able to detect patients at risk of SND, with an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI, 0.65-0.82). A score of 3 had a sensitivity of 85%, a specificity of 50%, a VPN of 87%, and a VPP of 44 % to predict SND.

CONCLUSIONS

In this study, we demonstrate that moTBI patients have a significant risk of SND. A simple weighted score at hospital admission could be able to detect patients at risk of SND. The use of the score may enable optimization of care resources for these patients.

Predictors of outcomes in geriatric patients with moderate traumatic brain injury after ground level falls

Introduction

The elderly population constitutes one of the fastest-growing demographic groups globally. Within this population, mild to moderate traumatic brain injuries (TBI) resulting from ground level falls (GLFs) are prevalent and pose significant challenges. Between 50 and 80% of TBIs in older individuals are due to GLFs. These incidents result in more severe outcomes and extended recovery periods for the elderly, even when controlling for injury severity. Given the increasing incidence of such injuries it becomes essential to identify the key factors that predict complications and in-hospital mortality. Therefore, the aim of this study was to pinpoint the top predictors of complications and in-hospital mortality in geriatric patients who have experienced a moderate TBI following a GLF.

Methods

Data were obtained from the American College of Surgeons' Trauma Quality Improvement Program database. A moderate TBI was defined as a head AIS ≤ 3 with a Glasgow Coma Scale (GCS) 9-13, and an AIS ≤ 2 in all other body regions. Potential predictors of complications and in-hospital mortality were included in a logistic regression model and ranked using the permutation importance method.

Results

A total of 7,489 patients with a moderate TBI were included in the final analyses. 6.5% suffered a complication and 6.2% died prior to discharge. The top five predictors of complications were the need for neurosurgical intervention, the Revised Cardiac Risk Index, coagulopathy, the spine abbreviated injury severity scale (AIS), and the injury severity score. The top five predictors of mortality were head AIS, age, GCS on admission, the need for neurosurgical intervention, and chronic obstructive pulmonary disease.

Conclusion

When predicting both complications and in-hospital mortality in geriatric patients who have suffered a moderate traumatic brain injury after a ground level fall, the most important factors to consider are the need for neurosurgical intervention, cardiac risk, and measures of injury severity. This may allow for better identification of at-risk patients, and at the same time resulting in a more equitable allocation of resources.

Which curve is better? A comparative analysis of trauma scoring systems in a South Asian country

Objectives

A diverse set of trauma scoring systems are used globally to predict outcomes and benchmark trauma systems. There is a significant potential benefit of using these scores in low and middle-income countries (LMICs); however, its standardized use based on type of injury is still limited. Our objective is to compare trauma scoring systems between neurotrauma and polytrauma patients to identify the better predictor of mortality in low-resource settings.

Methods

Data were extracted from a digital, multicenter trauma registry implemented in South Asia for a secondary analysis. Adult patients (≥18 years) presenting with a traumatic injury from December 2021 to December 2022 were included in this study. Injury Severity Score (ISS), Trauma and Injury Severity Score (TRISS), Revised Trauma Score (RTS), Mechanism/GCS/Age/Pressure score and GCS/Age/Pressure score were calculated for each patient to predict in-hospital mortality. We used receiver operating characteristic curves to derive sensitivity, specificity and area under the curve (AUC) for each score, including Glasgow Coma Scale (GCS).

Results

The mean age of 2007 patients included in this study was 41.2±17.8 years, with 49.1% patients presenting with neurotrauma. The overall in-hospital mortality rate was 17.2%. GCS and RTS proved to be the best predictors of in-hospital mortality for neurotrauma (AUC: 0.885 and 0.874, respectively), while TRISS and ISS were better predictors for polytrauma patients (AUC: 0.729 and 0.722, respectively).

Conclusion

Trauma scoring systems show differing predictability for in-hospital mortality depending on the type of trauma. Therefore, it is vital to take into account the region of body injury for provision of quality trauma care. Furthermore, context-specific and injury-specific use of these scores in LMICs can enable strengthening of their trauma systems.

Level of evidence

Level III.

Inherent Susceptibility to Acquired Epilepsy in Selectively Bred Rats Influences the Acute Response to Traumatic Brain Injury

Traumatic brain injury (TBI) often causes seizures associated with a neuroinflammatory response and neurodegeneration. TBI responses may be influenced by differences between individuals at a genetic level, yet this concept remains understudied. Here, we asked whether inherent differences in one's vulnerability to acquired epilepsy would determine acute physiological and neuroinflammatory responses acutely after experimental TBI, by comparing selectively bred "seizure-prone" (FAST) rats with "seizure-resistant" (SLOW) rats, as well as control parental strains (Long Evans and Wistar rats). Eleven-week-old male rats received a moderate-to-severe lateral fluid percussion injury (LFPI) or sham surgery. Rats were assessed for acute injury indicators and neuromotor performance, and blood was serially collected. At 7 days post-injury, brains were collected for quantification of tissue atrophy by cresyl violet (CV) histology, and immunofluorescent staining of activated inflammatory cells. FAST rats showed an exacerbated physiological response acutely post-injury, with a 100% seizure rate and mortality within 24 h. Conversely, SLOW rats showed no acute seizures and a more rapid neuromotor recovery compared with controls. Brains from SLOW rats also showed only modest immunoreactivity for microglia/macrophages and astrocytes in the injured hemisphere compared with controls. Further, group differences were apparent between the control strains, with greater neuromotor deficits observed in Long Evans rats compared with Wistars post-TBI. Brain-injured Long Evans rats also showed the most pronounced inflammatory response to TBI across multiple brain regions, whereas Wistar rats showed the greatest extent of regional brain atrophy. These findings indicate that differential genetic predisposition to develop acquired epilepsy (i.e., FAST vs. SLOW rat strains) determines acute responses after experimental TBI. Differences in the neuropathological response to TBI between commonly used control rat strains is also a novel finding, and an important consideration for future study design. Our results support further investigation into whether genetic predisposition to acute seizures predicts the chronic outcomes after TBI, including the development of post-traumatic epilepsy.

Intracranial lesion features in moderate-to-severe traumatic brain injury: relation to neurointensive care variables and clinical outcome

BACKGROUND

The primary aim was to determine the association of intracranial hemorrhage lesion type, size, mass effect, and evolution with the clinical course during neurointensive care and long-term outcome after traumatic brain injury (TBI).

METHODS

In this observational, retrospective study, 385 TBI patients treated at the neurointensive care unit at Uppsala University Hospital, Sweden, were included. The lesion type, size, mass effect, and evolution (progression on the follow-up CT) were assessed and analyzed in relation to the percentage of secondary insults with intracranial pressure > 20 mmHg, cerebral perfusion pressure < 60 mmHg, and cerebral pressure autoregulatory status (PRx) and in relation to Glasgow Outcome Scale-Extended.

RESULTS

A larger epidural hematoma (p < 0.05) and acute subdural hematoma (p < 0.001) volume, greater midline shift (p < 0.001), and compressed basal cisterns (p < 0.001) correlated with craniotomy surgery. In multiple regressions, presence of traumatic subarachnoid hemorrhage (p < 0.001) and intracranial hemorrhage progression on the follow-up CT (p < 0.01) were associated with more intracranial pressure-insults above 20 mmHg. In similar regressions, obliterated basal cisterns (p < 0.001) were independently associated with higher PRx. In a multiple regression, greater acute subdural hematoma (p < 0.05) and contusion (p < 0.05) volume, presence of traumatic subarachnoid hemorrhage (p < 0.01), and obliterated basal cisterns (p < 0.01) were independently associated with a lower rate of favorable outcome.

CONCLUSIONS

The intracranial lesion type, size, mass effect, and evolution were associated with the clinical course, cerebral pathophysiology, and outcome following TBI. Future efforts should integrate such granular data into more sophisticated machine learning models to aid the clinician to better anticipate emerging secondary insults and to predict clinical outcome.

Dynamic predictors of in-hospital and 3-year mortality after traumatic brain injury: A retrospective cohort study

BACKGROUND

Mortality risks after Traumatic Brain Injury (TBI) are understudied in critical illness. We sought to identify risks of mortality in critically ill patients with TBI using time-varying covariates.

METHODS

This single-center, six-year (2006-2012), retrospective cohort study measured demographics, injury characteristics, and daily data of acute TBI patients in the Intensive Care Unit (ICU). Time-varying Cox proportional hazards models assessed in-hospital and 3-year mortality.

RESULTS

Post-TBI ICU patients (n = 2664) experienced 20% in-hospital mortality (n = 529) and 27% (n = 706) 3-year mortality. Glasgow Coma Scale motor subscore (hazard ratio (HR) 0.58, p < 0.001), pupil reactivity (HR 3.17, p < 0.001), minimum glucose (HR 1.44, p < 0.001), mSOFA score (HR 1.81, p < 0.001), coma (HR 2.26, p < 0.001), and benzodiazepines (HR 1.38, p < 0.001) were associated with in-hospital mortality. At three years, public insurance (HR 1.78, p = 0.011) and discharge disposition (HR 4.48, p < 0.001) were associated with death.

CONCLUSIONS

Time-varying characteristics influenced in-hospital mortality post-TBI. Socioeconomic factors primarily affect three-year mortality.

A Long Short-Term Memory Network Using Resting-State Electroencephalogram to Predict Outcomes Following Moderate Traumatic Brain Injury

Although traumatic brain injury (TBI) is a global public health issue, not all injuries necessitate additional hospitalisation. Thinking, memory, attention, personality, and movement can all be negatively impacted by TBI. However, only a small proportion of nonsevere TBIs necessitate prolonged observation. Clinicians would benefit from an electroencephalography (EEG)-based computational intelligence model for outcome prediction by having access to an evidence-based analysis that would allow them to securely discharge patients who are at minimal risk of TBI-related mortality. Despite the increasing popularity of EEG-based deep learning research to create predictive models with breakthrough performance, particularly in epilepsy prediction, its use in clinical decision making for the diagnosis and prognosis of TBI has not been as widely exploited. Therefore, utilising 60s segments of unprocessed resting-state EEG data as input, we suggest a long short-term memory (LSTM) network that can distinguish between improved and unimproved outcomes in moderate TBI patients. Complex feature extraction and selection are avoided in this architecture. The experimental results show that, with a classification accuracy of 87.50 ± 0.05%, the proposed prognostic model outperforms three related works. The results suggest that the proposed methodology is an efficient and reliable strategy to assist clinicians in creating an automated tool for predicting treatment outcomes from EEG signals.

C-Reactive Protein and D-dimer as Prognostic Markers for Clinical Outcomes in Patients with Mild Traumatic Brain Injury: A Cross-Sectional Study

Objective

To investigate the use of prognostic markers such as C-reactive protein (CRP) and D-dimer for clinical outcomes in patients with mild traumatic brain injury (TBI).

Methods

This cross-sectional study was conducted on patients with mild head trauma who were admitted to the Emergency Department of Imam Khomeini Hospital (Sari, Iran). Data were collected from 2018 to 2019. Age, sex, the time of injury hospitalization, length of hospitalization, length of unconsciousness, blood pressure, heart rate, respiratory rate, and concomitant symptoms were all recorded using a pre-designed checklist. The patient's Glasgow Coma Scale (GCS), CRP, and D-dimer were also measured. Moreover, all patients underwent CT scan.

Results

This study included 74 patients with TBI. The mean age of the participants was 36.92±3.54. The mean CRP and D-dimer values were 5.69±0.77 and 0.58±0.11 in these patients, respectively. At the cut-off point of 11.50 for CRP, the sensitivity and specificity to detect the pathological lesions in CT scan were 75% and 95.50%, respectively (p<0.001). Additionally, with a D-dimer cut-off point of 0.90, the sensitivity and specificity for diagnosing pathological lesions in CT scan were 100% and 98.50%, respectively (p<0.001).

Conclusion

In general, the CRP and D-dimer levels of patients with mild TBI (GCS≥13) can be assessed to protect against CT-induced radiation exposure and subsequent disorders; if they do not exhibit clinical signs to increase the risk of adverse brain damage, such as reduced level of consciousness, drowsiness, and prolonged periods of unconsciousness.

Intracranial-Pressure-Monitoring-Assisted Management Associated with Favorable Outcomes in Moderate Traumatic Brain Injury Patients with a GCS of 9-11

Objective: With a mortality rate of 10−30%, a moderate traumatic brain injury (mTBI) is one of the most variable traumas. The indications for intracranial pressure (ICP) monitoring in patients with mTBI and the effects of ICP on patients’ outcomes are uncertain. The purpose of this study was to examine the indications of ICP monitoring (ICPm) and its effects on the long-term functional outcomes of mTBI patients. Methods: Patients with Glasgow Coma Scale (GCS) scores of 9−11 at Tangdu hospital, between January 2015 and December 2021, were enrolled and treated in this retrospective cohort study. We assessed practice variations in ICP interventions using the therapy intensity level (TIL). Six-month mortality and a Glasgow Outcome Scale Extended (GOS-E) score were the main outcomes. The secondary outcome was neurological deterioration (ND) events. The indication and the estimated impact of ICPm on the functional outcome were investigated by using binary regression analyses. Results: Of the 350 patients, 145 underwent ICP monitoring-assisted management, and the other 205 patients received a standard control based on imaging or clinical examinations. A GCS ≤ 10 (OR 1.751 (95% CI 1.216−3.023), p = 0.003), midline shift (mm) ≥ 2.5 (OR 3.916 (95% CI 2.076−7.386) p < 0.001), and SDH (OR 1.772 (95% CI 1.065−2.949) p = 0.028) were predictors of ICP. Patients who had ICPm (14/145 (9.7%)) had a decreased 6-month mortality rate compared to those who were not monitored (40/205 (19.5%), p = 0.011). ICPm was linked to both improved neurological outcomes at 6 months (OR 0.815 (95% CI 0.712−0.933), p = 0.003) and a lower ND rate (2 = 11.375, p = 0.010). A higher mean ICP (17.32 ± 3.52, t = −6.047, p < 0.001) and a more significant number of ICP > 15 mmHg (27 (9−45.5), Z = −5.406, p < 0.001) or ICP > 20 mmHg (5 (0−23), Z = −4.635, p < 0.001) 72 h after injury were associated with unfavorable outcomes. The best unfavorable GOS-E cutoff value of different ICP characteristics showed that the mean ICP was >15.8 mmHg (AUC 0.698; 95% CI, 0.606−0.789, p < 0.001), the number of ICP > 15 mmHg was >25.5 (AUC 0.681; 95% CI, 0.587−0.774, p < 0.001), and the number of ICP > 20 mmHg was >6 (AUC 0.660; 95% CI, 0.561−0.759, p < 0.001). The total TIL score during the first 72 h post-injury in the non-ICP group (9 (8, 11)) was lower than that of the ICP group (13 (9, 17), Z = −8.388, p < 0.001), and was associated with unfavorable outcomes. Conclusion: ICPm-assisted management was associated with better clinical outcomes six months after discharge and lower incidences of ND for seven days post-injury. A mean ICP > 15.8 mmHg, the number of ICP > 15 mmHg > 25.5, or the number of ICP > 20 mmHg > 6 implicate an unfavorable long-term prognosis after 72 h of an mTBI.

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.

The Wolfson Assessment Matrix: a potential tool to support clinicians in establishing access to specialized neuro rehabilitation by capturing important prognostic factors. Sharing more equitable and transparent criteria

BACKGROUND

Specialized Rehabilitation Services (SRSs) are designed to offer intensive multidisciplinary rehabilitation to patients with complex needs, who are expected to make significant functional gains in their ADLs over a relatively limited period of time. Although national guidelines offer a guidance on how to band patients by complexity, there is no consensus on how to screen patients with regard to rehabilitation prognosis.

AIM

The aim of this study was to improve the selection of patients admitted to an SRS, defining transparent and equitable prognostic criteria to guide clinicians' decision making.

DESIGN

This is a retrospective observational study SETTING: an SRS in the UK.

POPULATION

We included 121 patients affected by a neurological condition consecutively admitted for multidisciplinary rehabilitation.

METHODS

Rehabilitation Complexity Scale Extended is used to describe rehabilitation complexity. A short list of potential barriers to rehabilitation was analysed to predict the functional outcome measured by the Functional Independent Measure and the Barthel Index.

RESULTS

Older age, a heavier burden of co-morbidities, pre-morbid cognitive difficulties or dementia and a lower function level at admission were the most important variables to predict a lower functional gain.

CONCLUSIONS

We have used this list of barriers to create the Wolfson Assessment Matrix as a potential support tool to guide clinicians navigating through the different rehabilitation service options when assessing complex patients for eligibility to an SRS.

CLINICAL REHABILITATION IMPACT

SRSs are highly expensive services representing a possible step along the rehabilitation pathway for patients with complex needs. A tool such as the Wolfson Assessment Matrix would represent a step forward to help consistency in decision making regarding appropriateness for SRSs. It would also help to set realistic long-term goals with patients and families and support Health Services in the further development of alternative rehabilitation settings.

Nationwide improvements in geriatric mortality due to traumatic brain injury in Japan

BACKGROUND

Traumatic brain injury (TBI), both isolated and in combination with extracranial lesions, is a global health problem associated with high mortality. Among various risk factors for poor clinical outcomes, age is the most important independent predictor of mortality in patients with TBI. TBI-related mortality is expected to increase as the society ages. However, in a super-aged society such as Japan, little is known about the trend of TBI-related mortality among older adults. Herein, we assessed the nationwide trend of the incidence and clinical outcomes of geriatric patients with TBI in Japan using the national Japanese Trauma Data Bank (JTDB) registry.

METHODS

In this retrospective cohort study, cases of TBI (aged ≥65 years) in hospitals registered with the JTDB database between January 2004 and December 2018 were included. In-hospital mortality was the primary outcome, and mortality in the emergency department was the secondary outcome. The odds ratios (ORs) and 95% confidence intervals (CIs) for in-hospital deaths with respect to 3-year periods were assessed using multivariable analysis after adjusting for potential confounders.

RESULTS

The main cause of TBI in older individuals was falls. The proportion of patients who died after hospitalization during the study period decreased markedly from 29.5% (194/657) during 2004-2006 to 14.2% (1309/9240) during 2016-2018 in the isolated TBI group (adjusted OR = 0.42, 95% CI: 0.33-0.53) and from 48.0% (119/248) during 2004-2006 to 21.7% (689/3172) during 2016-2018 in the multiple trauma group (adjusted OR = 0.32, 95% CI: 0.23-0.45). The adjusted ORs for the 3-year increment were 0.84 (95% CI: 0.81-0.88) and 0.78 (95% CI: 0.75-0.83) for the isolated TBI and multiple trauma groups, respectively.

CONCLUSIONS

Using the national JTDB registry, we demonstrated a nationwide reduction in TBI-related mortality. Our findings in the super-aged society of Japan may provide insight for the treatment of geriatric patients with TBI worldwide.

Predicting Neurological Deterioration after Moderate Traumatic Brain Injury: Development and Validation of a Prediction Model Based on Data Collected on Admission

Moderate traumatic brain injury (mTBI) is a heterogeneous entity that poorly defined in the literature. mTBI patients suffer from a high rate of neurological deterioration (ND), which is usually accompanied with poor prognosis and no definitive methods to predict. The purpose of this study is to develop and validate a prediction model that estimates the ND risk in mTBI patients using data collected on admission. Retrospectively collected 479 mTBI patients' data in our department were analyzed by logistic regression models. Bivariable logistic regression identified variables with a p-value<0.05. Multivariable logistic regression modeling with backward stepwise elimination was used to determine reduced parameters and establish a prediction model. The discrimination efficacy, calibration efficacy, and clinical utility of the prediction model were evaluated. The prediction model was validated using 176 patients' data collected from another hospital. Eight independent prognostic factors were identified: hypertension, Marshall's scale (types III and IV), subdural hemorrhage (SDH), location of contusion (LOC) (frontal and temporal contusions), Injury Severity Score (ISS) >13, D-dimer level >11.4 mg/L, Glasgow Coma Scale (GCS) score ≤10, and platelet (PLT) count ≤152×109/L. A prediction model was established and was shown as a nomogram. Using bootstrapping, internal validation showed that the C-statistic of the prediction model was 0.881 (95% confidence interval (CI): 0.849-0.909). The results of external validation showed that the nomogram could predict ND with an area under the curve (AUC) of 0.827 (95% CI: 0763.-0.880). The present model, based on simple parameters collected on admission, can predict the risk of ND in mTBI patients accurately. The high discriminative ability indicates the potential of this model for classifying mTBI patients according to ND risk.

Clinical Deterioration and Neurocritical Care Utilization in Pediatric Patients With Glasgow Coma Scale Score of 9-13 After Traumatic Brain Injury: Associations With Patient and Injury Characteristics

OBJECTIVES

To define the clinical characteristics of hospitalized children with moderate traumatic brain injury and identify factors associated with deterioration to severe traumatic brain injury.

DESIGN

Retrospective cohort study.

SETTING

Tertiary Children's Hospital with Level 1 Trauma Center designation.

PATIENTS

Inpatient children less than 18 years old with an International Classification of Diseases code for traumatic brain injury and an admission Glasgow Coma Scale score of 9-13.

MEASUREMENTS AND RESULTS

We queried the National Trauma Data Bank for our institutional data and identified 177 patients with moderate traumatic brain injury from 2010 to 2017. These patients were then linked to the electronic health record to obtain baseline and injury characteristics, laboratory data, serial Glasgow Coma Scale scores, CT findings, and neurocritical care interventions. Clinical deterioration was defined as greater than or equal to 2 recorded values of Glasgow Coma Scale scores less than or equal to 8 during the first 48 hours of hospitalization. Thirty-seven patients experienced deterioration. Children who deteriorated were more likely to require intubation (73% vs 26%), have generalized edema, subdural hematoma, or contusion on CT scan (30% vs 8%, 57% vs 37%, 35% vs 16%, respectively), receive hypertonic saline (38% vs 7%), undergo intracranial pressure monitoring (24% vs 0%), were more likely to be transferred to inpatient rehabilitation following hospital discharge (32% vs 5%), and incur greater costs of care ($25,568 vs $10,724) (all p < 0.01). There was no mortality in this cohort. Multivariable regression demonstrated that a higher Injury Severity Score, a higher initial international normalized ratio, and a lower admission Glasgow Coma Scale score were associated with deterioration to severe traumatic brain injury in the first 48 hours (p < 0.05 for all).

CONCLUSIONS

A substantial subset of children (21%) presenting with moderate traumatic brain injury at a Level 1 pediatric trauma center experienced deterioration in the first 48 hours, requiring additional resource utilization associated with increased cost of care. Deterioration was independently associated with an increased international normalized ratio higher Injury Severity Score, and a lower admission Glasgow Coma Scale score.

Investigating the Association between Orthopedic Fractures and Head Injury due to Road Traffic Accidents

BACKGROUND

Traumatic head injury (THI) due to road traffic accidents (RTAs) is a global health problem. Studies exploring the association between RTA-related THI and concurrent orthopedic fractures are lacking. We aim to provide a detailed analysis of this association and its impact on inhospital outcomes.

METHODS

Retrospective analysis of RTA-related THI associated with orthopedic fractures admitted to a large tertiary center, Southwest, Saudi Arabia, over ten years. Descriptive statistics for participant demographics and clinical outcomes were represented by percentages. The associations between head injury diagnosis or orthopedic fractures region and patient demographics are analyzed using the Chi-square test. Post hoc analysis for the significant Chi-square values was carried out by calculating the significant adjusted residuals. Adjust p value was obtained by using the Benjamini-Hochberg procedure to control for multiplicity testing. A p value less than 0.05 was considered statistically significant.

RESULTS

Concurrent orthopedic fractures are present in one-tenth of RTA-related THI. The cohort was dominated by young males, with 46.5% of the population between 18 and 29 years old. There was a significant association between the head injury diagnosis and the region of orthopedic fracture (p = 0.028). The type of head injury had significant associations with mortality and duration of hospital stay (p = 0.039 and p = 0.037, respectively). The region of orthopedic fracture significantly (p = 0.018) affected the duration of hospital stay, with fractures in the clavicle/shoulder region significantly (p = 0.035) having a short course of hospital admission.

CONCLUSION

Orthopedic fractures concomitant with RTA-related THI are common. The associations between the two injuries tend to happen in specific patterns. The inhospital stay duration and mortality significantly correlated with the site of the head or orthopedic injury. Knowledge of these patterns improves the care of THI victims, triaging, and resource allocations.

Ability of neutrophil-to-lymphocyte ratio to predict secondary neurological impairment in patients with mild to moderate head injury. A retrospective study

BACKGROUND

The main objective was to assess the performance of the neutrophil-lymphocyte ratio (NLR) for early prediction of delayed neurological impairment and cerebral contusion worsening in patients with mild-to-moderate traumatic brain injury (TBI).

METHODS

Over a 3-year period, every adult patient triaged to our level 1 trauma center with brain contusion and Glasgow Coma Scale (GCS) of 10 or greater were retrospectively included. The main study outcome was the occurrence of delayed clinical deterioration, defined as a GCS < 10 and/or a secondary need for mechanical ventilation, within 5 days after TBI. The performance of NLR for prediction of delayed clinical deterioration was assessed by receiver operating characteristic (ROC) curve.

RESULTS

Overall, 115 patients were included and 16 (14%) presented a delayed clinical deterioration. Overall, the NLR at ED admission was higher in patients who developed a delayed clinical deterioration (18 [12-29] vs 8 [5-13], p = 0.0003). The area under the ROC curves for NLR at ED admission in predicting delayed clinical deterioration was 0.79 [0.65-0.93] and NLR > 15 was found to be independently associated with the occurrence of delayed clinical deterioration (adjusted OR = 10.1 [95%CI: 2.3-45.6]).

CONCLUSION

The NLR at ED admission was independently associated with the occurrence of delayed clinical deterioration, although limited by a poor discriminative value by itself. Further studies are needed to test the predictive value of composite scoring systems including NLR for prevention of under-triage of patients with mild-to-moderate TBI.

Effect of Continuous Infusion of Hypertonic Saline vs Standard Care on 6-Month Neurological Outcomes in Patients With Traumatic Brain Injury: The COBI Randomized Clinical Trial

IMPORTANCE

Fluid therapy is an important component of care for patients with traumatic brain injury, but whether it modulates clinical outcomes remains unclear.

OBJECTIVE

To determine whether continuous infusion of hypertonic saline solution improves neurological outcome at 6 months in patients with traumatic brain injury.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter randomized clinical trial conducted in 9 intensive care units in France, including 370 patients with moderate to severe traumatic brain injury who were recruited from October 2017 to August 2019. Follow-up was completed in February 2020.

INTERVENTIONS

Adult patients with moderate to severe traumatic brain injury were randomly assigned to receive continuous infusion of 20% hypertonic saline solution plus standard care (n = 185) or standard care alone (controls; n = 185). The 20% hypertonic saline solution was administered for 48 hours or longer if patients remained at risk of intracranial hypertension.

MAIN OUTCOMES AND MEASURES

The primary outcome was Extended Glasgow Outcome Scale (GOS-E) score (range, 1-8, with lower scores indicating worse functional outcome) at 6 months, obtained centrally by blinded assessors and analyzed with ordinal logistic regression adjusted for prespecified prognostic factors (with a common odds ratio [OR] >1.0 favoring intervention). There were 12 secondary outcomes measured at multiple time points, including development of intracranial hypertension and 6-month mortality.

RESULTS

Among 370 patients who were randomized (median age, 44 [interquartile range, 27-59] years; 77 [20.2%] women), 359 (97%) completed the trial. The adjusted common OR for the GOS-E score at 6 months was 1.02 (95% CI, 0.71-1.47; P = .92). Of the 12 secondary outcomes, 10 were not significantly different. Intracranial hypertension developed in 62 (33.7%) patients in the intervention group and 66 (36.3%) patients in the control group (absolute difference, -2.6% [95% CI, -12.3% to 7.2%]; OR, 0.80 [95% CI, 0.51-1.26]). There was no significant difference in 6-month mortality (29 [15.9%] in the intervention group vs 37 [20.8%] in the control group; absolute difference, -4.9% [95% CI, -12.8% to 3.1%]; hazard ratio, 0.79 [95% CI, 0.48-1.28]).

CONCLUSIONS AND RELEVANCE

Among patients with moderate to severe traumatic brain injury, treatment with continuous infusion of 20% hypertonic saline compared with standard care did not result in a significantly better neurological status at 6 months. However, confidence intervals for the findings were wide, and the study may have had limited power to detect a clinically important difference.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03143751.

The impact of delayed time to first CT head on functional outcomes after blunt head trauma with moderately depressed GCS

Purpose

Recent work suggests patients with moderately depressed Glasgow Coma Scale (GCS) score in the Emergency Department (ED) who do not undergo immediate head CT (CTH) have delayed neurosurgical intervention and longer ED stay. The present study objective was to determine the impact of time to first CTH on functional neurologic outcomes in this patient population.

Methods

Blunt trauma patients presenting to our Level I trauma center (11/2015–10/2019) with first ED GCS 9–12 were retrospectively identified and included. Transfers and those with extracranial AIS ≥ 3 were excluded. The study population was stratified into Immediate (≤ 1 h) and Delayed (1–6 h) CTH groups based on time from ED arrival to first CTH. Outcomes included functional outcomes at hospital discharge based on the Modified Rankin Scale (mRS).

Results

After exclusions, 564 patients were included: 414 (73%) with Immediate CTH and 150 (27%) Delayed CTH. Both groups arrived with median GCS 11 and alcohol/drug intoxication did not differ (p > 0.05). AIS Head/Neck was comparable (3[3–4] vs. 3[3–3], p = 0.349). Time to ED disposition decision and ED exit were significantly shorter after Immediate CTH (2.8[1.5–5.3] vs. 5.2[3.6–7.5]h, p < 0.001 and 5.5[3.3–8.9] vs. 8.1[5.2–11.7]h, p < 0.001). Functional outcomes were slightly worse after Immediate CTH (mRS 2[1–4] vs. 2[1–3], p = 0.002). Subgroup analysis of patients requiring neurosurgical intervention demonstrated a greater proportion of moderately disabled patients with a lower proportion of severely disabled or dead patients after Immediate CTH as compared to Delayed CTH (51 vs. 20%, p = 0.063 and 35 vs. 60%, p = 0.122).

Conclusions

Immediate CTH shortened time to disposition decision out of the ED and ED exit. Patients requiring neurosurgical intervention after Immediate CTH had improved functional outcomes when compared to those undergoing Delayed CTH. These differences did not reach statistical significance in this single-center study and, therefore, a large, multicenter study is the next step in demonstrating the potential functional outcomes benefit of Immediate CTH after blunt head trauma.

Cause of Death after Traumatic Brain Injury: A Population-Based Health Record Review Analysis Referenced for Nonhead Trauma

INTRODUCTION

Traumatic brain injury (TBI) is a leading cause of disability and is associated with decreased survival. Although it is generally accepted that TBI increases risk of death in acute and postacute periods after injury, causes of premature death after TBI in the long term are less clear.

METHODS

A cohort sample of Olmsted County, Minnesota, residents with confirmed TBI from January 1987 through December 1999 was identified. Each case was assigned an age- and sex-matched non-TBI referent case, called regular referent. Confirmed TBI cases with simultaneous nonhead injuries were identified, labeled special cases. These were assigned 2 age- and sex-matched special referents with nonhead injuries of similar severity. Underlying causes of death in each case were categorized using death certificates, International Classification of Diseases, Ninth Revision, International Statistical Classification of Diseases, Tenth Revision, and manual health record review. Comparisons were made over the study period and among 6-month survivors.

RESULTS

Case-regular referent pairs (n = 1,257) were identified over the study period, and 221 were special cases. In total, 237 deaths occurred among these pairs. A statistically significant difference was observed between total number of deaths among all cases (n = 139, 11%) and regular referents (n = 98, 8%) (p = 0.006) over the entire period. This outcome was not true for special cases (32/221, 14%) and special referents (61/441, 14%) (p = 0.81). A greater proportion of deaths by external cause than all other causes was observed in all cases (52/139, 37%) versus regular referents (3/98, 3%) and in special cases (13/32, 41%) versus special referents (5/61, 8%) (p < 0.001 for both). Among all case-referent pairs surviving 6 months, no difference was found between total number of deaths (p = 0.82). The underlying cause of death between these 2 groups was significantly different for external causes only (p < 0.01). For special cases surviving 6 months versus special referents, no difference was observed in total number of deaths (p = 0.24) or underlying causes of death (p = 1.00) between groups.

DISCUSSION/CONCLUSION

This population-based case-matched referent study showed that increased risk of death after TBI existed only during the first 6 months after injury, and the difference was due to external causes.

Comorbidity in traumatic brain injury and functional outcomes: a systematic review

INTRODUCTION

Comorbidities in people with traumatic brain injury (TBI) may negatively impact injury recovery course and result in long-term disability. Despite the high prevalence of several categories of comorbidities in TBI, little is known about their association with patients' functional outcomes. We aimed to systematically review the current evidence to identify comorbidities that affect functional outcomes in adults with TBI.

EVIDENCE ACQUISITION

A systematic search of Medline, Cochrane Central Register of Controlled Trials, Embase and PsycINFO was conducted from 1997 to 2020 for prospective and retrospective longitudinal studies published in English. Three researchers independently screened and assessed articles for fulfillment of the inclusion criteria. Quality assessment followed the Quality in Prognosis Studies tool and the Scottish Intercollegiate Guidelines Network methodology recommendations.

EVIDENCE SYNTHESIS

Twenty-two studies of moderate quality discussed effects of comorbidities on functional outcomes of patients with TBI. Cognitive and physical functioning were negatively affected by comorbidities, although the strength of association, even within the same categories of comorbidity and functional outcome, differed from study to study. Severity of TBI, sex/gender, and age were important factors in the relationship. Due to methodological heterogeneity between studies, meta-analyses were not performed.

CONCLUSIONS

Emerging evidence highlights the adverse effect of comorbidities on functional outcome in patients with TBI, so clinical attention to this topic is timely. Future research on the topic should emphasize time of comorbidity onset in relation to the TBI event, to support prevention, treatment, and rehabilitation. PROSPERO registration (CRD 42017070033).

Association of Hyperchloremia and Acute Kidney Injury in Patients With Traumatic Brain Injury

Introduction:

Hypertonic saline is often used to treat patients with traumatic brain injury. It carries the undesired side effect of hyperchloremia, which has been linked to acute kidney injury (AKI). We sought to evaluate the relationship of hyperchloremia and AKI in this population and whether the absolute exposure to hyperchloremia, including maximal hyperchloremia and duration of hyperchloremia were associated with AKI.

Methods:

A retrospective study of severe traumatic brain injury patients who received hypertonic saline at a single academic institution. Demographics, head abbreviated injury scale, development of hyperchloremia (Cl ≥ 115), duration of hyperchloremia, highest chloride level, duration of hypertonic saline use, admission GFR, and administration of nephrotoxic medications were abstracted. The outcome of interest was the association between renal function and hyperchloremia.

Results:

A total of 123 patients were included in the study. Multivariable logistic regression analysis demonstrated that only duration of hyperchloremia ( p = 0.014) and GFR on admission ( p = 0.004) were independently associated with development of AKI. The number of days of hypertonic saline infusion ( p = 0.79) without the persistence of hyperchloremia and highest serum chloride levels ( p = 0.23) were not predictive of AKI development.

Discussion:

In patients with traumatic brain injury, admission GFR and prolonged hyperchloremia rather than the highest chloride level or the duration of hypertonic saline infusion were associated with the development of AKI.

Effects of hospital-acquired pneumonia on long-term recovery and hospital resource utilization following moderate to severe traumatic brain injury

BACKGROUND

Individuals with traumatic brain injury (TBI) have extended inpatient hospital stays that include prolonged mechanical ventilation, increasing risk for infections, including pneumonia. Studies show the negative short-term effects of hospital-acquired pneumonia (HAP) on hospital-based outcomes; however, little is known of its long-term effects.

METHODS

A prospective cohort study was conducted. National Trauma Databank and Traumatic Brain Injury Model Systems were merged to derive a cohort of 3,717 adults with moderate-to-severe TBI. Exposure data were gathered from the National Trauma Databank, and outcomes were gathered from the Traumatic Brain Injury Model Systems. The primary outcome was the Glasgow Outcome Scale-Extended (GOS-E), which was collected at 1, 2, and 5 years postinjury. The GOS-E was categorized as favorable (>5) or unfavorable (≤5) outcomes. A generalized estimating equation model was fitted estimating the effects of HAP on GOS-E over the first 5 years post-TBI, adjusting for age, race, ventilation status, brain injury severity, injury severity score, thoracic Abbreviated Injury Scale score of 3 or greater, mechanism of injury, intraventricular hemorrhage, and subarachnoid hemorrhage.

RESULTS

Individuals with HAP had a 34% (odds ratio, 1.34; 95% confidence interval, 1.15-1.56) increased odds for unfavorable GOS-E over the first 5 years post-TBI compared with individuals without HAP, after adjustment for covariates. There was a significant interaction between HAP and follow-up, such that the effect of HAP on GOS-E declined over time. Sensitivity analyses that weighted for nonresponse bias and adjusted for differences across trauma facilities did not appreciably change the results. Individuals with HAP spent 10.1 days longer in acute care and 4.8 days longer in inpatient rehabilitation and had less efficient functional improvement during inpatient rehabilitation.

CONCLUSION

Individuals with HAP during acute hospitalization have worse long-term prognosis and greater hospital resource utilization. Preventing HAP may be cost-effective and improve long-term recovery for individuals with TBI. Future studies should compare the effectiveness of different prophylaxis methods to prevent HAP.

LEVEL OF EVIDENCE

Prospective cohort study, level III.

Neuroprotective Effects of Serpina3k in Traumatic Brain Injury

Traumatic brain injury (TBI) is a major cause of disability and mortality worldwide, in part resulting from secondary apoptosis of neurons in peri-contusion areas. Serpina3k, a serine protease inhibitor, has been shown to inhibit apoptosis in injury models. In this study, we investigated the anti-apoptotic function of serpina3k in vivo using a mouse model of TBI, as well as the underlying neuroprotective mechanism in vitro using the SH-SY5Y human neuroblastoma cell line. TBI was induced in adult male C57BL/6 mice using controlled cortical impact. Serpina3k protein was intravenously administered at a concentration of 0.5 mg/kg twice daily for up to 14 days. SH-SY5Y cells were subjected to biaxial stretch injury and then treated with different concentrations of serpina3k. We found that endogenous serpina3k protein levels were elevated in peri-contusion areas of the mouse brain following TBI. Serpina3k-treated mice had fewer apoptotic neurons, lower levels of oxidative stress, and showed greater recovery of neurological deficits relative to vehicle-treated mice. Meanwhile, in the SH-SY5Y cell injury model, serpina3k at an optimal concentration (150 nM) inhibited the generation of intracellular reactive oxygen species, abrogated changes of the mitochondrial membrane potential, and reduced the phospho-extracellular regulated protein kinases (p-ERK)/ERK, phospho-P38 (p-P38)/P38, B cell lymphoma (Bcl)-2-associated X protein/Bcl-2, and cleaved caspase-3/caspase-3 ratios, thereby reducing the apoptosis rate. These results demonstrate that serpina3k exerts a neuroprotective function following TBI and thus has therapeutic potential.

Injury, Sleep, and Functional Outcome in Hospital Patients With Traumatic Brain Injury

PROBLEM

Uninterrupted nighttime sleep is associated with better cognition and functional outcomes in healthy adults, but the relationship between sleep and functional outcome in individuals hospitalized with severe traumatic brain injury (TBI) remains to be clarified.

OBJECTIVE

The aims of this study were to (1) describe nighttime rest-activity variables-wake bouts (counts), total wake time (minutes), and sleep efficiency (SE) (percentage; time asleep/time in bed)-in people on a neuroscience step-down unit (NSDU) post-TBI and (2) describe the association between injury and nighttime rest-activity on post-TBI functional outcome (using Functional Independence Measure [FIM] at discharge from inpatient care).

METHODS

This study is a cross-sectional, descriptive pilot study. We recruited participants from the NSDU (n = 17 [age: mean (SD), 63.4 (17.9)]; 82% male, 94% white) who wore wrist actigraphy (source of nighttime rest-activity variables) for up to 5 nights. For injury variables, we used Glasgow Coma Scale (GCS) score and Injury Severity Score (ISS). We used Spearman ρ and regression to measure associations.

RESULTS

Glasgow Coma Scale mean (SD) score was 8.8 (4.9), ISS mean (SD) score was 23.6 (6.7), and FIM mean (SD) score was 48 (14.5). Averages of nighttime rest-activity variables (8 PM-7 AM) were as follows: SE, 73% (SD, 16); wake bouts, 41 counts (SD, 18); total wake time, 74 minutes (SD, 47). Correlations showed significance between FIM and GCS (P = .005) and between SE and GCS (P = .015). GCS was the only statistically significant variable associated with FIM (P = .013); we eliminated other variables from the model as nonsignificant (P > .10). Sleep efficiency and FIM association was nonsignificant (P = .40). In a separate model (ISS, GCS, and SE [dependent variable]), GCS was significant (P = .04), but ISS was not (P = .25).

CONCLUSION

Patients with severe TBI on the NSDU have poor actigraphic sleep at night. GCS has a stronger association to functional outcome than nighttime rest-activity variables.

Mild, moderate and severe: terminology implications for clinical and experimental traumatic brain injury

PURPOSE OF REVIEW

When describing clinical or experimental traumatic brain injury (TBI), the adjectives 'mild,' 'moderate' and 'severe' are misleading. 'Mild' clinical TBI frequently results in long-term disability. 'Severe' rodent TBI actually resembles mild or complicated mild clinical TBI.

RECENT FINDINGS

Many mild TBI patients appear to have recovered completely but have postconcussive symptoms, deficits in cognitive and executive function and reduced cerebral blood flow. After moderate TBI, 31.8% of patients died or were discharged to skilled nursing or hospice. Among survivors of moderate and severe TBI, 44% were unable to return to work. On MRI, 88% of mild TBI patients have evidence of white matter damage, based on measurements of fractional anisotropy and mean diffusivity/apparent diffusion coefficient. After sports concussion, clinically recovered patients have abnormalities in functional connectivity on functional MRI. Methylphenidate improved fatigue and cognitive impairment and, combined with cognitive rehabilitation, improved memory and executive functioning. In comparison to clinical TB, because the entire spectrum of experimental rodent TBI, although defined as moderate or severe, more closely resembles mild or complicated mild clinical TBI.

SUMMARY

Many patients after mild or moderate TBI suffer long-term sequelae and should be considered a major target for translational research. Treatments that improve outcome in rodent TBI, even when the experimental injuries are defined as severe, might be most applicable to mild or moderate TBI.

Neuronavigation as a minimally invasive tool in the treatment of intracranial gunshot injuries

Gunshot injury is the most common cause of penetrating brain injury. The in-hospital mortality for civilians with penetrating craniocerebral injury is 52-95%. There are many surgical techniques suitable for the treatment of survivors. We report a surgical technique consisting of neuronavigation guidance for wound treatment with smaller incisions and craniotomies, followed by bullet removal if feasible. We report case of a 15 year old male patient who sustained an accidental firearm injury to the occipital region, submitted to surgical treatment that consisted in a minimally invasive approach guided by neuronavigation. Immediate neurological examination showed inferior homonymous quadrantanopsia alone as a clinical finding. Patient was discharged after one week, and no complications arised in follow-up. We conclude that using neuronavigation as a tool was effective in the reported case and that minimally invasive neurosurgical techniques may be a safe and efficient option for the treatment of traumatic brain injuries caused by firearm projectiles.

The Importance of Inter-Species Variation in Traumatic Brain Injury-Induced Alterations of Microglial-Axonal Interactions

Interactions between microglia and neuronal components are important for normal CNS function. They are also associated with neuroinflammation and many pathological processes and several studies have explored these interactions in terms of phagocytic engulfment. Much progress has also been made in understanding the consequences of chronic neuroinflammatory changes following trauma. However, little is known about acute alterations to these physical non-phagocytic microglial-neuronal interactions following traumatic brain injury (TBI), and particularly to what degree these post-injury interactions may be influenced by the animal species utilized in pre-clinical models of TBI. To investigate these problems, we evaluated the physical interactions between microglia and injured axons acutely (6 h and 1 day) following central fluid percussion injury (cFPI) in both rats and micro pigs. The physical interactions between Iba-1+ microglia and either normal MBP+ myelinated fibers or APP+ injured axonal swellings in the thalamus were assessed following injury or sham via quantitative image analysis of 3D confocal micrographs. The results indicated that the physical interactions between microglia and injured axonal swellings decreased by nearly half in rats 6 h following cFPI but was consistent with sham control at 1 day post-cFPI. This reduction was also observed in non-injured intact fibers at both timepoints following TBI in the rat. Microglial process interactions with injured axons in the micro pig, however, increased nearly 2-fold compared to interactions with intact axonal segments 1 day post-cFPI. This study shows that the species utilized for in vivo pre-clinical studies influences the manner in which microglial-axonal interactions change following TBI. These species differences can be leveraged to further our understanding of the mechanisms involved in microglial process convergence and how these neuro-immune interactions alter the progression of axonal injury following TBI.