Serum ethanol levels: predictor of survival after severe traumatic brain injury

Alcohol is not associated with increased mortality in adolescent traumatic brain injury patients

PURPOSE

Compared to adults, there is a paucity of data regarding the association of a positive alcohol screen (PAS) and outcomes in adolescent patients with traumatic brain injury (TBI). We hypothesize adolescent TBI patients with a PAS on admission to have increased mortality compared to patients with a negative alcohol screen.

METHODS

The 2017 Trauma Quality Improvement Program database was queried for patients aged 13-17 years presenting with a TBI and serum alcohol screen. Patients with missing information regarding midline shift on imaging and Glasgow Coma Scale (GCS) score were excluded. A multivariable logistic regression analysis for mortality was performed.

RESULTS

From 2553 adolescent TBI patients with an alcohol screen, 220 (8.6%) had a PAS. Median injury severity scores and rates of penetrating trauma (all p > 0.05) were similar between alcohol positive and negative patients. Patients with a PAS had a similar mortality rate (13.2% vs. 12.1%, p = 0.64) compared to patients with a negative screen. Multivariate logistic regression controlling for risk factors associated with mortality revealed a PAS to confer a similar risk of mortality compared to alcohol negative patients (p = 0.40).

CONCLUSION

Adolescent TBI patients with a PAS had similar associated risk of mortality compared to patients with a negative alcohol screen.

Alcohol and trauma: the influence of blood alcohol levels on the severity of injuries and outcome of trauma patients - a retrospective analysis of 6268 patients of the TraumaRegister DGU®

Background

Blood alcohol level (BAL) has previously been considered as a factor influencing the outcome of injured patients. Despite the well-known positive correlation between alcohol-influenced traffic participation and the risk of accidents, there is still no clear evidence of a positive correlation between blood alcohol levels and severity of injury. The aim of the study was to analyze data of the TraumaRegister DGU^® (TR-DGU), to find out whether the blood alcohol level has an influence on the type and severity of injuries as well as on the outcome of multiple-trauma patients.

Methods

Datasets from 11,842 trauma patients of the TR-DGU from the years 2015 and 2016 were analyzed retrospectively and 6268 patients with a full dataset and an AIS ≥ 3 could be used for evaluation. Two groups were formed for data analysis. A control group with a BAL = 0 ‰ (BAL negative) was compared to an alcohol group with a BAL of ≥0.3‰ to < 4.0‰ (BAL positive). Patients with a BAL >  0‰ and <  0.3‰ were excluded. They were compared with regard to various preclinical, clinical and physiological parameters. Additionally, a subgroup analysis with a focus on patients with a traumatic brain injury (TBI) was performed.

A total of 5271 cases were assigned to the control group and 832 cases to the BAL positive group. 70.3% (3704) of the patients in the control group were male. The collective of the control group was on average 5.7 years older than the patients in the BAL positive group (p < .001). The control group showed a mean ISS of 20.3 and the alcohol group of 18.9 (p = .007). In terms of the injury severity of head, the BAL positive group was significantly higher on average than the control group (p <  0.001), whereas the control group showed a higher AIS to thorax and extremities (p <  0.001). The mean Glasgow Coma Scale (GCS) was 10.8 in the BAL positive group and 12.0 in the control group (p <  0.001). Physiological parameters such as base excess (BE) and International Normalized Ratio (INR) showed reduced values ​​for the BAL positive group. However, neither the 24-h mortality nor the overall mortality showed a significant difference in either group (p = 0.19, p = 0.14). In a subgroup analysis, we found that patients with a relevant head injury (AIS: Abbreviated Injury Scale head ≥3) and positive BAL displayed a higher survival rate compared to patients in the control group with isolated TBI (p < 0.001).

Conclusions

This retrospective study analyzed the influence of the blood alcohol level in severely injured patients in a large national dataset. BAL positive patients showed worse results with regard to head injuries, the GCS and to some other physiological parameters. Finally, neither the 24-h mortality nor the overall mortality showed a significant difference in either group. Only in a subgroup analysis the mortality rate in BAL negative patients with TBI was significantly higher than the mortality rate of BAL positive patients with TBI. This mechanism is not yet fully understood and is discussed controversially in the literature.

Effect of ethanol in carbon monoxide poisoning and delayed neurologic sequelae: A prospective observational study

Objectives

Carbon monoxide (CO) is one of the most common poisoning substances, which causes mortality and morbidity worldwide. Delayed neurologic sequelae (DNS) have been reported to occur from several days to months after exposure to CO. Thus, there is a need for prevention, recognition, and treatment of DNS. Patients with CO poisoning as a component of intentional suicide often also consume ethanol, but there is debate regarding its role in DNS. We explored whether ethanol has a neuroprotective effect in CO poisoning.

Methods

This prospective observational study included patients who visited the emergency department from August 2016 to August 2019 due to CO poisoning. After treatment of acute CO poisoning, patients were interviewed by telephone to ascertain whether DNS had occurred within 2 weeks, 1 month, and 3 months from the time of CO exposure.

Results

During the study period, 171 patients were enrolled. 28 patients (16.37%) developed DNS. The initial Glasgow Coma Scale (GCS) scores were 15 (10.5–15) for the non-DNS group and 10 (7–15) for the DNS group (p = 0.002). The ethanol levels were 11.01 ± 17.58 mg/dL and 1.49 ± 2.63 mg/dL for each group (p < 0.001). In multivariate logistic regression analysis, the GCS score had an odds ratio of 0.770 (p < 0.001) and the ethanol level had 0.882 (p < 0.030) for onset of DNS.

Conclusions

Higher ethanol level and higher initial GCS score were associated with lower incidence of DNS. Ethanol could have a neuroprotective effect on the occurrence of DNS in CO poisoning patients.

Does Alcohol Intoxication Protect Patients from Severe Injury and Reduce Hospital Mortality? The Association of Alcohol Consumption with the Severity of Injury and Survival in Trauma Patients

Alcohol-related motor vehicle collisions are a major cause of mortality in trauma patients. This prospective observational study investigated the influence of antecedent alcohol use on outcomes in trauma patients who survived to reach the hospital. From 2005 to 2011, all patients who were older than 18 years and were admitted as a result of motor vehicle crashes were included. Blood alcohol concentration (BAC) was routinely measured for each patient on admission. Patients were divided into four groups based on their BAC level, which included nondrinking, BAC less than 100, BAC 100 to 200, and BAC 200 mg/dL or greater. Patient demographics, physical status and injury severity on admission, length of hospital stay, and outcome were compared between the groups. Odds ratios of having a severe injury, prolonged hospital stay, and mortality were estimated. Patients with a positive BAC had an increased risk of sustaining craniofacial and thoracoabdominal injuries. Odds ratios of having severe injuries (Injury Severity Score [ISS] 16 or greater) and a prolonged hospital stay were also increased. However, for those patients whose ISS was 16 or greater and who also had a brain injury, risk of fatality was significantly reduced if they were intoxicated (BAC 200 mg/dL or greater) before injury. Alcohol consumption does not protect patients from sustaining severe injuries nor does it shorten the length of hospital stay. However, there were potential survival benefits related to alcohol consumption for patients with brain injuries but not for those without brain injuries. Additional research is required to investigate the mechanism of this association further.

The Effect of Alcohol Consumption on Geriatric Trauma Outcomes

BACKGROUND

There is little consensus in the literature regarding the effect of ethanol intoxication on trauma outcomes. Data on its effect in the elderly are even sparser. Our aim was to better define the impact of alcohol use in the geriatric trauma population.

MATERIALS AND METHODS

We conducted a retrospective review at a level I trauma center looking at admissions from January 2015 through December 2018. Patients were grouped by age: 15-64 y old (YOUNG) versus ≥ 65 y old (OLD). Blood alcohol content (BAC) ≤0.10 g/dL was ETOH (-), and BAC >0.10 g/dL was ETOH (+). These were then propensity matched by injury severity score and mechanism of injury. Fisher's exact test and linear regression were applied as appropriate. Significance was defined as P < 0.05.

RESULTS

There were 8754 patients admitted during the study time frame. A total of 6106 patients were YOUNG and 2647 were OLD. A total of 146 (5.5%) OLD patients were ETOH (+), whereas 1488 (24.4%) YOUNG patients were ETOH (+) (P < 0.0001). To assess the impact of alcohol between the two age groups, 285 OLD patients were propensity matched with 285 YOUNG patients. Mortality was significantly higher in the OLD (11.9%) group than that in the YOUNG (3.5%) group (P < 0.001). Morbidity was also higher in OLD versus YOUNG patients overall (P < 0.05). The presence of ethanol did not significantly impact morbidity or mortality in YOUNG or OLD patients.

CONCLUSIONS

Higher mortality and morbidity is unsurprising in geriatric trauma patients; however, alcohol does not appear to play a significant role in these outcomes.

Traumatic brain injury and alcohol intoxication: effects on injury patterns and short-term outcome

Purpose

A significant number of patients with traumatic brain injuries (TBI) are diagnosed with elevated blood alcohol concentration (BAC). Recent literature suggests a neuroprotective effect of alcohol on TBI, possibly associated with less morbidity and mortality. Our goal is to analyze the association of different levels of BAC with TBI characteristics and outcome.

Methods

Adult patients with moderate to severe TBI (AIS ≥ 2) and measured BAC admitted to the Trauma Centre West (TCW), during the period 2010–2015, were retrospectively analyzed. Data included injury severity (AIS), length of hospitalization, admittance to the Intensive Care Unit (ICU) and in-hospital mortality. The association of BAC with ICU admittance and in-hospital mortality was analyzed using multivariable logistic regression analysis with correction for potentially confounding variables.

Results

BACs were available in 2,686 patients of whom 42% had high, 26% moderate, 6% low and 26% had normal levels. Patients with high BAC’s were predominantly male, were younger, had lower ISS scores, lower AIS-head scores and less concomitant injuries compared to patients in the other BAC subgroups. High BACs were associated with a lower risk for in-hospital mortality (AOR 0.36, 95% CI 0.14–0.97). Also, patients with moderate and high BACs were less often admitted to the ICU (respectively, AOR 0.36, 95% CI 0.25–0.52 and AOR 0.40, 95% CI 0.29–0.57).

Conclusion

The current study suggests that in patients with moderate to severe TBI, increasing BACs are associated with less severe TBI, less ICU admissions and a higher survival. Further research into the pathophysiological mechanism is necessary to help explain these findings.

Predicting mortality in traumatic intracranial hemorrhage

OBJECTIVE

Traumatic intracranial hemorrhage (tICH) is a significant source of morbidity and mortality in trauma patients. While prognostic models for tICH outcomes may assist in alerting clinicians to high-risk patients, previously developed models face limitations, including low accuracy, poor generalizability, and the use of more prognostic variables than is practical. This study aimed to construct a simpler and more accurate method of risk stratification for all tICH patients.

METHODS

The authors retrospectively identified a consecutive series of 4110 patients admitted to their institution's level 1 trauma center between 2003 and 2013. For each admission, they collected the patient's sex, age, systolic blood pressure, blood alcohol concentration, antiplatelet/anticoagulant use, Glasgow Coma Scale (GCS) score, Injury Severity Score, presence of epidural hemorrhage, presence of subdural hemorrhage, presence of subarachnoid hemorrhage, and presence of intraparenchymal hemorrhage. The final study population comprised 3564 patients following exclusion of records with missing data. The dependent variable under study was patient death. A k-fold cross-validation was carried out with the best models selected via the Akaike Information Criterion. These models risk stratified the study partitions into grade I (< 1% predicted mortality), grade II (1%-10% predicted mortality), grade III (10%-40% predicted mortality), or grade IV (> 40% predicted mortality) tICH. Predicted mortalities were compared with actual mortalities within grades to assess calibration. Concordance was also evaluated. A final model was constructed using the entire data set. Subgroup analysis was conducted for each hemorrhage type.

RESULTS

Cross-validation demonstrated good calibration (p < 0.001 for all grades) with a mean concordance of 0.881 (95% CI 0.865-0.898). In the authors' final model, older age, lower blood alcohol concentration, antiplatelet/anticoagulant use, lower GCS score, and higher Injury Severity Score were all associated with greater mortality. Subgroup analysis showed successful stratification for subarachnoid, intraparenchymal, grade II-IV subdural, and grade I epidural hemorrhages.

CONCLUSIONS

The authors developed a risk stratification model for tICH of any GCS score with concordance comparable to prior models and excellent calibration. These findings are applicable to multiple hemorrhage subtypes and can assist in identifying low-risk patients for more efficient resource allocation, facilitate family conversations regarding goals of care, and stratify patients for research purposes. Future work will include testing of more variables, validation of this model across institutions, as well as creation of a simplified model whose outputs can be calculated mentally.

STAT6 mediates the effect of ethanol on neuroinflammatory response in TBI

Traumatic brain injury (TBI) and ethanol intoxication (EI) frequently coincide, particularly in young subjects. However, the mechanisms of their interaction remain poorly understood. Among other pathogenic pathways, TBI induces glial activation and neuroinflammation in the hippocampus, resulting in acute and chronic hippocampal dysfunction. In this regard, we investigated the role of EI affecting these responses unfolding after TBI. We used a blunt, weight-drop approach to model TBI in mice. Male mice were pre-administered with ethanol or vehicle to simulate EI. The neuroinflammatory response in the hippocampus was assessed by monitoring the expression levels of >20 cytokines, the phosphorylation status of transcription factors and the phenotype of microglia and astrocytes. We used AS1517499, a brain-permeable STAT6 inhibitor, to elucidate the role of this pathway in the EI/TBI interaction. We showed that TBI causes the elevation of IL-33, IL-1β, IL-38, TNF-α, IFN-α, IL-19 in the hippocampus at 3 h time point and concomitant EI results in the dose-dependent downregulation of IL-33, IL-1β, IL-38, TNF-α and IL-19 (but not of IFN-α) and in the selective upregulation of IL-13 and IL-12. EI is associated with the phosphorylation of STAT6 and the transcription of STAT6-controlled genes. Moreover, ethanol-induced STAT6 phosphorylation and transcriptional activation can be recapitulated in vitro by concomitant exposure of neurons to ethanol, depolarization and inflammatory stimuli (simulating the acute trauma). Acute STAT6 inhibition prevents the effects of EI on IL-33 and TNF-α, but not on IL-13 and negates acute EI beneficial effects on TBI-associated neurological impairment. Additionally, EI is associated with reduced microglial activation and astrogliosis as well as preserved synaptic density and baseline neuronal activity 7 days after TBI and all these effects are prevented by acute administration of the STAT6 inhibitor concomitant to EI. EI concomitant to TBI exerts significant immunomodulatory effects on cytokine induction and microglial activation, largely through the activation of STAT6 pathway, ultimately with beneficial outcomes.

Alcohol protects the CNS by activating HSF1 and inducing the heat shock proteins

Although alcohol abuse and dependence have profound negative health consequences, emerging evidence suggests that exposure to low/moderate concentrations of ethanol protects multiple organs and systems. In the CNS, moderate drinking decreases the risk of dementia and Alzheimer's disease. This neuroprotection correlates with an increased expression of the heat shock proteins (HSPs). Multiple epidemiological studies revealed an inverse association between ethanol intoxication and traumatic brain injury mortality. In this case, ethanol-induced HSPs limit the inflammatory immune response diminishing cell death and improving the neurobehavioural outcome. Ethanol also protects the brain against ischemic injuries via the HSPs. In our laboratory, we demonstrated that ethanol increased the expression of several HSP genes in neurons and astrocytes by activating the transcription factor, heat shock factor 1 (HSF1). HSF1 induces HSPs that target misfolded proteins for refolding or degradation, increasing the survival chances of the cells. These data indicate that ethanol neuroprotection is mediated by the activation HSF1 and the induction of HSPs.

Alcohol in Traumatic Brain Injury: Toxic or Therapeutic?

BACKGROUND

Alcohol (EtOH) poses a challenge in traumatic brain injuries (TBIs) given its metabolic and neurologic impact. Studies have had opposing results regarding mortality and complication rates in the intoxicated TBI patient. We hypothesized that trauma mechanism, brain injury severity, and blood alcohol concentration (BAC) would influence the impact of EtOH on mortality in TBI.

METHODS

We performed a single-institution retrospective review of consecutive adult trauma patients tested for EtOH and a diagnosis of TBI. The primary outcome was mortality, and secondary outcomes included infectious complications. The primary analysis included univariate and multivariate regression comparing mortality between intoxicated and sober patients, at different values of BAC, different brain injury severities, and among mechanisms of trauma.

RESULTS

Admission EtOH was assessed in 583 patients with TBI, with 256 testing positive for EtOH and 327 testing negative. Overall, EtOH was associated with lower mortality on univariate analysis (4.7% versus 8.9%, P = 0.05) but not on multivariate analysis (P = 0.21). There was no effect of EtOH on mortality when patients were stratified by brain injury severity or among penetrating trauma victims. However, EtOH was associated with lower overall infectious complications on univariate and multivariate regression. Finally, EtOH was predictive of mortality with an area under the receiver operator characteristic curve of 0.83.

CONCLUSIONS

We found that EtOH is not associated with mortality in the patient with TBI, suggesting no causative effect. However, EtOH showed some predictability of mortality based on a receiver operator characteristic analysis. Interestingly, EtOH was associated with lower infectious complications, suggesting an immunomodulatory effect of EtOH in TBI.

Exposing the bidirectional effects of alcohol on coagulation in trauma: Impaired clot formation and decreased fibrinolysis in rotational thromboelastometry

BACKGROUND

Alcohol has been associated with altered viscoelastic testing in trauma, indicative of impaired coagulation. Such alterations, however, show no correlation to coagulopathy-related outcomes. Other data suggest that alcohol may inhibit fibrinolysis. We sought to clarify these mechanisms after traumatic injury using thromboelastometry (ROTEM), hypothesizing that alcohol-related clot formation impairment may be counter-balanced by inhibited fibrinolysis.

METHODS

Laboratory, demographic, clinical, and outcome data were prospectively collected from 406 critically injured trauma patients at a Level I trauma center. ROTEM and standard coagulation measures were conducted in parallel. Univariate comparisons were performed by alcohol level (EtOH), with subsequent regression analysis.

RESULTS

Among 274 (58%) patients with detectable EtOH, median EtOH was 229 mg/dL. These patients were primarily bluntly injured and had lower GCS (p < 0.05) than EtOH-negative patients, but had similar admission pH and injury severity (p = NS). EtOH-positive patients had prolonged ROTEM clotting time and rate of clot formation time (CFT/α); they also had decreased fibrinolysis (max lysis %; all p < 0.05). In linear regression, for every 100 mg/dL increase in EtOH, clotting time increased by 13 seconds and fibrinolysis decreased by 1.5% (both p < 0.05). However, EtOH was not an independent predictor of transfusion requirements or mortality. In high-EtOH patients with coagulopathic ROTEM tracings, transfusion rates were significantly lower than expected, relative to EtOH-negative patients with similar ROTEM findings.

CONCLUSION

As assayed by ROTEM, alcohol appears to have a bidirectional effect on coagulation in trauma, both impairing initial clot formation and inhibiting fibrinolysis. This balancing of mechanisms may explain lack of correlation between altered ROTEM and coagulopathy-related outcomes. Viscoelastic testing should be used with caution in intoxicated trauma patients.

LEVEL OF EVIDENCE

Epidemiological study, level III.

The Neuroprotective Effect of Ethanol Intoxication in Traumatic Brain Injury Is Associated with the Suppression of ErbB Signaling in Parvalbumin-Positive Interneurons

Ethanol intoxication (EI) is a frequent comorbidity of traumatic brain injury (TBI), but the impact of EI on TBI pathogenic cascades and prognosis is unclear. Although clinical evidence suggests that EI may have neuroprotective effects, experimental support is, to date, inconclusive. We aimed at elucidating the impact of EI on TBI-associated neurological deficits, signaling pathways, and pathogenic cascades in order to identify new modifiers of TBI pathophysiology. We have shown that ethanol administration (5 g/kg) before trauma enhances behavioral recovery in a weight-drop TBI model. Neuronal survival in the injured somatosensory cortex was also enhanced by EI. We have used phospho-receptor tyrosine kinase (RTK) arrays to screen the impact of ethanol on TBI-induced activation of RTK in somatosensory cortex, identifying ErbB2/ErbB3 among the RTKs activated by TBI and suppressed by ethanol. Phosphorylation of ErbB2/3/4 RTKs were upregulated in vGlut2⁺ excitatory synapses in the injured cortex, including excitatory synapses located on parvalbumin (PV)-positive interneurons. Administration of selective ErbB inhibitors was able to recapitulate, to a significant extent, the neuroprotective effects of ethanol both in sensorimotor performance and structural integrity. Further, suppression of PV interneurons in somatosensory cortex before TBI, by engineered receptors with orthogonal pharmacology, could mimic the beneficial effects of ErbB inhibitors. Thus, we have shown that EI interferes with TBI-induced pathogenic cascades at multiple levels, with one prominent pathway, involving ErbB-dependent modulation of PV interneurons.

Effects of acute ethanol intoxication in an ovine peritonitis model

BACKGROUND

Acute ethanol intoxication has been shown to have contrasting effects on outcomes in sepsis. The aim of this study was to explore the effects of acute ethanol intoxication on hemodynamics, renal function, brain perfusion and lactate/pyruvate in an ovine sepsis model.

METHODS

Anesthetized, mechanically ventilated female sheep were randomized to an ethanol group (n = 7), which received 1 g/kg ethanol diluted in intravenous (i.v.) saline infusion or a control group (n = 7), which received the same volume of i.v. saline. Both groups received the treatment for a period of 2 h prior to induction of sepsis by intraperitoneal injection of feces. Other treatment included fluid resuscitation but no vasopressors or antibiotics. Global hemodynamics, renal blood flow, brain cortex laser Doppler flowmetry and microdialysis analyses were recorded hourly.

RESULTS

In the ethanol group, blood ethanol concentrations were 137 ± 29 mg/dL at the time of feces injection and decreased to become undetectable by 12 h. Arterial hypotension occurred earlier in the ethanol than in the control group (8 [7-12] vs. 14 [11-20] hours, p = 0.03). Lactate levels increased to > 2 mmol/L earlier in the ethanol group. Renal dysfunction (9 [6-13] vs. 13 [12-15] hours, p = 0.05) and oliguria (urine output < 0.5 mL/kg/h; 10 [7-12] vs. 13 [12, 13] hours, p = 0.01) developed earlier in the ethanol than in the control group. Brain blood flow and lactate/pyruvate were unaffected. There was no significant difference in survival time.

CONCLUSIONS

Acute ethanol intoxication in this model of peritonitis resulted in earlier development of shock and renal dysfunction but did not alter brain perfusion and metabolism or short-term survival.

Blood Ethanol Levels Are Not Related to Coagulation Changes, as Measured by Thromboelastography, in Traumatic Brain Injury Patients

BACKGROUND

Brain injury is a leading cause of death and disability in trauma patients. Ethanol (EtOH) use near the time of injury may contribute to worse outcomes in these patients by exacerbating coagulopathy. There are limited data regarding the effects of EtOH on coagulation and progression of traumatic intracranial hemorrhage (TICH).

METHODS

We performed a retrospective analysis of a prospective observational study of 168 trauma patients with TBI at an urban level 1 trauma center. Thromboelastography (TEG) was performed on admission and over the subsequent 48 hours. Demographic, physiologic, and outcomes data were collected. Computed tomography imaging of the head performed within the first 48 hours of admission was analyzed for progression of TICH.

RESULTS

Thirty-six percent of patients (n = 61) had positive blood EtOH on admission (median EtOH level = 198 mg/dL [range, 16-376 mg/dL]). EtOH-positive patients were less severely injured than EtOH-negative patients (P = 0.01). Other admission demographic and physiologic variables were similar between groups. There were no significant differences in TEG values between EtOH-positive and EtOH-negative patients on admission or during the subsequent 48 hours. There were no differences in radiographic progression of hemorrhage, the need for neurosurgical procedure, or mortality between EtOH-positive and EtOH-negative patients.

CONCLUSIONS

EtOH use near the time of traumatic injury was not associated with alterations in coagulation, as measured by traditional coagulation tests or by TEG, in patients with TICH. Furthermore, a positive blood alcohol at admission was not associated with increased mortality or need for neurosurgical procedure these patients.

Neuroprotective effect of acute ethanol intoxication in TBI is associated to the hierarchical modulation of early transcriptional responses

Ethanol intoxication is a risk factor for traumatic brain injury (TBI) but clinical evidence suggests that it may actually improve the prognosis of intoxicated TBI patients. We have employed a closed, weight-drop TBI model of different severity (2cm or 3cm falling height), preceded (-30min) or followed (+20min) by ethanol administration (5g/Kg). This protocol allows us to study the interaction of binge ethanol intoxication in TBI, monitoring behavioral changes, histological responses and the transcriptional regulation of a series of activity-regulated genes (immediate early genes, IEGs). We demonstrate that ethanol pretreatment before moderate TBI (2cm) significantly reduces neurological impairment and accelerates recovery. In addition, better preservation of neuronal numbers and cFos+cells was observed 7days after TBI. At transcriptional level, ethanol reduced the upregulation of a subset of IEGs encoding for transcription factors such as Atf3, c-Fos, FosB, Egr1, Egr3 and Npas4 but did not affect the upregulation of others (e.g. Gadd45b and Gadd45c). While a subset of IEGs encoding for effector proteins (such as Bdnf, InhbA and Dusp5) were downregulated by ethanol, others (such as Il-6) were unaffected. Notably, the majority of genes were sensitive to ethanol only when administered before TBI and not afterwards (the exceptions being c-Fos, Egr1 and Dusp5). Furthermore, while severe TBI (3cm) induced a qualitatively similar (but quantitatively larger) transcriptional response to moderate TBI, it was no longer sensitive to ethanol pretreatment. Thus, we have shown that a subset of the TBI-induced transcriptional responses were sensitive to ethanol intoxication at the instance of trauma (ultimately resulting in beneficial outcomes) and that the effect of ethanol was restricted to a certain time window (pre TBI treatment) and to TBI severity (moderate). This information could be critical for the translational value of ethanol in TBI and for the design of clinical studies aimed at disentangling the role of ethanol intoxication in TBI.

Neuroprotective effect of ethanol in acute carbon monoxide intoxication: A retrospective study

In acute carbon monoxide (CO) intoxication, treatment of neurologic injury and prevention of neurological sequelae are primary concerns. Ethanol is the one of the frequent substances which is co-ingested in intentional CO poisoning. Neuroprotective effect of ethanol was highlighted and demonstrated in isolated brain injury recently. We assessed the neuroprotective effect of ethanol in acute CO intoxication using magnetic resonance imaging (MRI).We retrospectively reviewed medical records for patients who visited an emergency medical center of a university-affiliated hospital during a period of 73 months, from March 2009 to April 2015. Enrolled patients were divided into 2 groups, patients with or without abnormal brain lesion in brain MRI. Multivariate logistic regression analysis was performed to assess the factors associated with brain injury in MRI.A total of 109 patients with acute CO intoxication were evaluated of which 66 (60.55%) tested positive in brain MRI. MRI lesion-positive patients were more likely to have electrocardiogram change, elevation of serum troponin I and s100 protein level and lower serum ethanol level. Serum ethanol positivity was an independent factor for prevalence of brain injury in MRI in acute CO poisoning.This study revealed that ethanol which is co-ingested in acute CO intoxication may work the neuroprotective effect and could consequence more favorable neurological outcome in acute CO intoxication.

Cannabis Use Has Negligible Effects Following Severe Traumatic Injury

Nearly half of all states have legalized medical marijuana or recreational-use marijuana. As more states move toward legalization, the effects on injured patients must be evaluated. This study sought to determine effects of cannabis positivity at the time of severe injury on hospital outcomes compared with individuals negative for illicit substances and those who were users of other illicit substances. A Level I trauma center performed a retrospective chart review covering subjects over a 2-year period with toxicology performed and an Injury Severity Score (ISS) of more than 16. These individuals were divided into the negative and positive toxicology groups, further divided into the marijuana-only, other drugs-only, and mixed-use groups. Differences in presenting characteristics, hospital length of stay, intensive care unit (ICU) stays, ventilator days, and death were compared. A total of 8,441 subjects presented during the study period; 2,134 (25%) of these had toxicology performed; 843 (40%) had an ISS of more than 16, with 347 having negative tests (NEG); 70 (8.3%) substance users tested positive only for marijuana (MO), 323 (38.3%) for other drugs-only, excluding marijuana (OD), and 103 (12.2%) subjects showed positivity for mixed-use (MU). The ISS was similar for all groups. No differences were identified in Glasgow Coma Scale (GCS), ventilator days, blood administration, or ICU/hospital length of stay when comparing the MO group with the NEG group. Significant differences occurred between the OD group and the NEG/MO/MU groups for GCS, ICU length of stay, and hospital charges. Cannabis users suffering from severe injury demonstrated no detrimental outcomes in this study compared with nondrug users.

Acute ethanol administration results in a protective cytokine and neuroinflammatory profile in traumatic brain injury

Ethanol intoxication is a common comorbidity in traumatic brain injury. To date, the effect of ethanol on TBI pathogenic cascades and resulting outcomes remains debated. A closed blunt weight-drop murine TBI model has been implemented to investigate behavioral (by sensorimotor and neurological tests), and neuro-immunological (by tissue cytokine arrays and immuno-histology) effects of ethanol intoxication on TBI. The effect of the occurrence of traumatic intracerebral hemorrhage was also studied. The results indicate that ethanol pretreatment results in a faster and better recovery after TBI with reduced infiltration of leukocytes and reduced microglia activation. These outcomes correspond to reduced parenchymal levels of GM-CSF, IL-6 and IL-3 and to the transient upregulation of IL-13 and VEGF, indicating an early shift in the cytokine profile towards reduced inflammation. A significant difference in the cytokine profile was still observed 24h post injury in the ethanol pretreated mice, as shown by the delayed peak in IL-6 and by the suppression of GM-CSF, IFN-γ, and IL-3. Seven days post-injury, ethanol-pretreated mice displayed a significant decrease both in CD45+ cells infiltration and in microglial activation. On the other hand, in the case of traumatic intracerebral hemorrhage, the cytokine profile was dominated by KC, CCL5, M-CSF and several interleukins and ethanol pretreatment did not produce any modification. We can thus conclude that ethanol intoxication suppresses the acute neuro-inflammatory response to TBI, an effect which is correlated with a faster and complete neurological recovery, whereas, the presence of traumatic intracerebral hemorrhage overrides the effects of ethanol.

Acute Alcohol Exposure and Risk of Mortality of Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

After traumatic brain injury (TBI), patients usually live with significant disability and socioeconomic burdens. Acute exposure to alcohol is considered a major risk factor for TBI. Numerous studies have examined whether alcohol exposure is related to the risk of mortality in patients with TBI, yet the results remain inconsistent. We performed a meta-analysis to assess whether acute alcohol exposure affects the mortality rate of TBI patients. We searched PubMed, EMBASE, and the Cochrane Library up to November 2015 for relevant studies. We screened studies based on their inclusion criteria and selected the studies that reported mortality rate, which included 18 observational studies. We used R to analyze the included data. An initial result showed that the presence of a positive blood alcohol concentration (BAC) had no significant relation with mortality rate (OR = 0.92, 95% CI = 0.83 to 1.01), but there was notable heterogeneity along with variable results according to sensitivity analysis. For the BAC-positive population, low BAC (1 to 100 mg/dl) carried a higher risk of mortality than moderate BAC (100 to 230 mg/dl) (OR = 1.40, 95% CI = 1.09 to 1.81), moderate and high BAC as a single category (>100 mg/dl) (OR = 1.57, 95% CI = 1.28 to 1.94), or high BAC (>230 mg/dl) (OR = 1.76, 95% CI = 1.34 to 2.30). However, moderate BAC did not increase the mortality risk when compared with high BAC (OR = 1.20, 95% CI = 0.89 to 1.63). Whether positive BAC at the time of admission after TBI reduces mortality rate compared with the rate under negative BAC remains unknown. In addition, low BAC (1 to 100 mg/dl) poses a risk of mortality compared with higher BAC. Further studies assessing the effect of alcohol between the BAC-positive group and the BAC-negative group are still needed.

Influence of alcohol use on mortality and expenditure during hospital admission: a cross-sectional study

OBJECTIVES

This study was designed to investigate the effect of alcohol intoxication on clinical presentation of hospitalised adult trauma patients at a Level I trauma centre using propensity score matching.

DESIGN

Cross-sectional study.

SETTING

Taiwan.

PARTICIPANTS

Detailed data of 929 hospitalised adult trauma patients with alcohol intoxication, aged 20-65 years, and 10 104 corresponding patients without alcohol intoxication were retrieved from the Trauma Registry System between 1 January 2009 and 31 December 2014. Alcohol intoxication was defined as a blood alcohol concentration (BAC) ≥50 mg/dL.

MAIN OUTCOME MEASURES

In-hospital mortality and expenditure.

RESULTS

Patients with alcohol intoxication presented with significantly higher short-term mortality (OR: 3.0, 95% CI 2.0 to 4.4; p<0.001) than patients without alcohol intoxication. However, on comparison with propensity score-matched patients with respect to sex, age, comorbidity, Glasgow Coma Scale (GCS), injury region based on Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS), alcohol intoxication did not significantly influence mortality (OR: 0.8, 95% CI 0.5 to 1.4; p=0.563). This implied that the higher mortality of alcohol-intoxicated patients was attributable to patient characteristics such as a higher injury severity rather than alcohol intoxication. Even on comparison with sex-matched, age-matched and comorbidity-matched patients without alcohol intoxication, patients with alcohol intoxication still had significantly higher total expenditure (17.4% higher), cost of operation (40.3% higher), cost of examination (52.8% higher) and cost of pharmaceuticals (38.3% higher).

CONCLUSIONS

The associated higher mortality of adult trauma patients with alcohol intoxication was completely attributable to other patient characteristics and associated injury severity rather than the effects of alcohol. However, patients with alcohol intoxication incurred significantly higher expenditure than patients without alcohol intoxication, even on comparison with sex-matched, age-matched and comorbidity-matched patients without alcohol intoxication.

Alcohol and mortality after moderate to severe traumatic brain injury: a meta-analysis of observational studies

OBJECT

Experimental studies have shown numerous neuroprotective properties of alcohol (“ethanol”) after TBI, but clinical studies have provided conflicting results. The authors aimed to assess the relationship between positive blood alcohol concentration (BAC) on hospital admission and mortality after moderate to severe traumatic brain injury (TBI).

METHODS

The authors searched 8 databases for observational studies reported between January 1, 1990, and October 7, 2013, and investigated the effect of BAC on mortality after moderate to severe TBI. Reviews of each study were conducted, and data were extracted according to the MOOSE and PRISMA guidelines. Study quality was assessed using the Newcastle-Ottawa scale. The Mantel-Haenszel fixed effect methodology was used to generate pooled estimates. Heterogeneity was dealt with by multiple sensitivity analyses.

RESULTS

Eleven studies with a total of 95,941 patients (42% BAC positive and 58% BAC negative) were identified for the primary analysis (overall mortality 12%). Primary analysis showed a significantly lower risk of death for BAC-positive patients compared with BAC-negative patients (crude mortality 11.0% vs 12.3%, pooled OR 0.84 [95% CI 0.81–0.88]), although flawed by heterogeneity (I2 = 68%). Multiple sensitivity analyses, including 55,949 and 51,772 patients, yielded similar results to the primary analysis (crude mortality 12.2% vs 14.0%, pooled OR 0.87 [95% CI 0.83–0.92] and crude mortality 8.7% vs 10.7%, pooled OR 0.78 [95% CI 0.74–0.83]) but with good study homogeneity (I2 = 36% and 14%).

CONCLUSIONS

Positive BAC was significantly associated with lower mortality rates in moderate to severe TBI. Whether this observation is due to selection bias or neuroprotective effects of alcohol remains unknown. Future prospective studies adjusting for TBI heterogeneity is advocated to establish the potential favorable effects of alcohol on outcome after TBI.

Alcohol Intake and Reduced Mortality in Patients with Traumatic Brain Injury

BACKGROUND

The purpose of our study was to determine whether alcohol intake influences short-term mortality in patients with traumatic brain injury (TBI), using a comprehensive trauma database.

METHODS

We collected data from 7 emergency departments (EDs) between June 1, 2008 and May 31, 2010, using the same data form. Cases were included if they met the following criteria: (i) older than 15 and (ii) injuries including TBI. Demographics and outcomes were compared between patients with and without alcohol intake. We present the risk of mortality using hazard ratios and 95% confidence intervals.

RESULTS

A total of 76,596 trauma patients visited the EDs during the study period; 12,980 patients were older than 15 and had TBI. There were 4,009 (30.9%) patients in the alcohol-intake group, of whom 3,306 (82.5%) patients were male, 1,450 (36.2%) patients were moved by ambulance, and 1,218 (30.4%) patients' injuries were intentional. The most frequent injury mechanism was falling down with alcohol intake and blunt injury without alcohol intake. Mortality rate was 1.0% with alcohol intake and 2.0% without alcohol intake. After adjusting for all factors related to mortality, the hazard ratio of mortality was 0.72 in the alcohol-intake group.

CONCLUSIONS

Mortality rate due to TBI in the alcohol-intake group appears to be lower compared to that in the no-alcohol-intake group after adjusting for main confounding variables.

The Moderation of Blood Alcohol Levels on Higher Odds of Survival among American Indians with Violent, Blunt-Force Traumatic Brain Injuries

This study assessed the moderation of blood alcohol level (BAL) and American Indian race on survival of patients with violent traumatic brain injury (TBI). An initial logistic regression model indicated that those who were American Indian and insured had higher odds of survival and those with higher injury severity scores and low-medium BAL were less likely to survive. A second logistic regression model including a relationship between American Indians and BAL found that American Indians had a higher odds of survival which tripled when they have no BAL. Low-medium and high BAL were associated with less likelihood of survival among White patients.

The emerging neuroprotective role of mitochondrial uncoupling protein-2 in traumatic brain injury

Traumatic brain injury (TBI) is a multifaceted disease with intrinsically complex heterogeneity and remains a significant clinical challenge to manage. TBI model systems have demonstrated many mechanisms that contribute to brain parenchymal cell death, including glutamate and calcium toxicity, oxidative stress, inflammation, and mitochondrial dysfunction. Mitochondria are critically regulated by uncoupling proteins (UCP), which allow protons to leak back into the matrix and thus reduce the mitochondrial membrane potential by dissipating the proton motive force. This uncoupling of oxidative phosphorylation from adenosine triphosphate (ATP) synthesis is potentially critical for protection against cellular injury as a result of TBI and stroke. A greater understanding of the underlying mechanism or mechanisms by which uncoupling protein-2 (UCP2) functions to maintain or optimize mitochondrial function, and the conditions which precipitate the failure of these mechanisms, would inform future research and treatment strategies. We posit that UCP2-mediated function underlies the physiological response to neuronal stress associated with traumatic and ischemic injury and that clinical development of UCP2-targeted treatment would significantly impact these patient populations. With a focus on clinical relevance in TBI, we synthesize current knowledge concerning UCP2 and its potential neuroprotective role and apply this body of knowledge to current and potential treatment modalities.

Ethanol and isolated traumatic brain injury

The aim of this systematic review was to determine whether ethanol is neuroprotective or associated with adverse effects in the context of traumatic brain injury (TBI). Approximately 30-60% of TBI patients are intoxicated with ethanol at the time of injury. We performed a systematic review of the literature using a combination of keywords for ethanol and TBI. Manuscripts were included if the population studied was human subjects with isolated moderate to severe TBI, acute ethanol intoxication was studied as an exposure variable and mortality reported as an outcome. The included studies were assessed for heterogeneity. A meta-analysis was performed and the pooled odds ratio (OR) for the association between ethanol and in-hospital mortality reported. There were seven studies eligible for analysis. A statistically significant association favouring reduced mortality with ethanol intoxication was found (OR 0.78; 95% confidence interval 0.73-0.83). Heterogeneity among selected studies was not statistically significant (p=0.25). Following isolated moderate-severe TBI, ethanol intoxication was associated with reduced in-hospital mortality. The retrospective nature of the studies, varying definitions of brain injury, degree of intoxication and presence of potential confounders limits our confidence in this conclusion. Further research is recommended to explore the potential use of ethanol as a therapeutic strategy following TBI.

The prevalence of positive drug and alcohol screens in elderly trauma patients

BACKGROUND

Alcohol and drug abuse are recognized to be significantly prevalent in trauma patients, and are frequent harbingers of injury. The incidence of substance abuse in elderly trauma patients has, however, been limitedly examined. The authors sought to identify the spectrum of positive alcohol and drug toxicology screens in patients ≥65 years admitted to a Level I trauma center.

METHODS

Patients ≥65 years old admitted to an American College of Surgeons (ACS) Level I trauma center over a 60--month period were identified from the trauma registry. Demographic data, blood alcohol content (BAC), and urine drug screen (UDS) results at admission were obtained and analyzed. The positive results were compared with individuals below 65 years in different substance categories using Fisher's exact test.

RESULTS

In the 5-year period studied, of the 4139 patients ≥65 years, 1302 (31.5%) underwent toxicological substance screening. A positive BAC was present in 11.1% of these patients and a positive UDS in 48.3%. The mean BAC level in those tested was 163 mg/dL and 69% of patients had a level >80 mg/dL.

CONCLUSIONS

These data show that alcohol and drug abuse are an issue in patients ≥65 years in our institution, though not as pervasive a problem as in younger populations. Admission toxicology screens, however, are important as an aid to identify geriatric individuals who may require intervention.

The effects of alcohol on coagulation in trauma patients: interpreting thrombelastography with caution

BACKGROUND

The effects of alcohol on coagulation after trauma remain unclear. In vitro studies show that alcohol may decrease clot strength and inhibit fibrinolysis. Observational data indicate that alcohol leads to altered thrombelastography (TEG) parameters indicative of impaired clot formation. Clinical studies have been inconclusive to date.

METHODS

Longitudinal plasma samples were prospectively collected from 415 critically injured trauma patients at a single Level 1 trauma center and were matched with demographic and outcome data. Citrated kaolin TEG and standard coagulation measures were performed in parallel. Univariate and group comparisons were performed by alcohol status, with subsequent linear and logistic regression analysis.

RESULTS

A total of 264 patients (63.6%) had detectable blood alcohol levels (EtOH, >10 mg/dL). These patients were primarily male (87% vs. 79%), were bluntly injured (77% vs. 59%), and had lower median Glasgow Coma Scale (GCS) score (9.5 vs. 14, all p < 0.05) than the EtOH-negative patients. There were no notable differences in pH (7.29 vs. 7.31, p = nonsignificant) or injury severity (median Injury Severity Score [ISS], 11 vs. 14; p = nonsignificant) between the groups. The alcohol-positive patients had a prolonged TEG citrated kaolin R-time (reaction time), or time to initial clot formation (5.91 minutes vs. 4.43 minutes, p = 0.013), prolonged K-time (kinetics time), or time to fixed level of clot strength (1.77 minutes vs. 1.43 minutes, p = 0.036), and decreased α angle (66.5 degrees vs. 70.2 degrees, p = 0.001). In multiple linear regression, for every 10-mg/dL increase in EtOH, R-time was prolonged by 3.84 seconds (p = 0.015), and α angle decreased by 0.11 degrees (p = 0.013). However, in multiple logistic regression analyses, EtOH was a negative predictor of coagulopathy by international normalized ratio (>1.3) and was not predictive of transfusion requirements or early or late mortality.

CONCLUSION

Patients with elevated EtOH present with impaired clot formation as assayed by TEG, but this does not correlate with standard measures of coagulopathy or with outcome. Reliance on TEG for determining coagulopathy in intoxicated trauma patients may lead to a misperceived hypocoagulable state and inappropriate transfusion. TEG appears to be affected by EtOH in a previously unreported way, warranting further investigation.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level III.

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

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

Effect of alcohol in traumatic brain injury: is it really protective?

BACKGROUND

Studies have proposed a neuroprotective role for alcohol (ETOH) in traumatic brain injury (TBI). We hypothesized that ETOH intoxication is associated with mortality in patients with severe TBI.

METHODS

Version 7.2 of the National Trauma Data Bank (2007-2010) was queried for all patients with isolated blunt severe TBI (Head Abbreviated Injury Score ≥4) and blood ETOH levels recorded on admission. Primary outcome measure was mortality. Multivariate logistic regression analysis was performed to assess factors predicting mortality and in-hospital complications.

RESULTS

A total of 23,983 patients with severe TBI were evaluated of which 22.8% (n = 5461) patients tested positive for ETOH intoxication. ETOH-positive patients were more likely to have in-hospital complications (P = 0.001) and have a higher mortality rate (P = 0.01). ETOH intoxication was an independent predictor for mortality (odds ratio: 1.2, 95% confidence interval: 1.1-2.1, P = 0.01) and development of in-hospital complications (odds ratio: 1.3, 95% confidence interval: 1.1-2.8, P = 0.009) in patients with isolated severe TBI.

CONCLUSIONS

ETOH intoxication is an independent predictor for mortality in patients with severe TBI patients and is associated with higher complication rates. Our results from the National Trauma Data Standards differ from those previously reported. The proposed neuroprotective role of ETOH needs further clarification.

Effects of time of hospital admission on outcomes after severe traumatic brain injury in Austria

BACKGROUND

The goal of this study was to compare outcomes of patients with severe traumatic brain injury (TBI) who had been admitted either during workdays from 7 a.m. to 7 p.m. ("regular service") or during any other time ("on-call service").

MATERIAL AND METHODS

Between March 2002 and April 2012, 17 Austrian centers enrolled TBI patients into two observational studies that focused on effects of guideline compliance (n = 400) and on prehospital and early hospital management (n = 777), respectively. Data on trauma severity, clinical status, treatment, and outcomes were collected prospectively. All patients with severe TBI (Glasgow Coma Scale score < 9) were selected for this analysis. Secondary transfers and patients with unsurvivable injuries were excluded. The International Mission for Prognosis and Analysis of Clinical Trials in TBI core model was used to estimate probabilities of hospital death and unfavorable long-term outcome (Glasgow Outcome Scale score < 4). Based on time of arrival, patients were assigned to groups "regular service" or "on-call service."

RESULTS

Data from 852 patients were analyzed (413 "regular," 439 "on-call service"). "On-call" patients were younger (45 vs. 51 years, P < 0.001) and had a higher rate of alcohol intoxication (41 vs. 11 %, P < 0.001). Trauma severity was comparable; the probabilities of death and unfavorable outcome were identical. There were no differences regarding computed tomography findings or treatment. Hospital mortality (24 vs. 28 %, P = 0.191) and rate of patients with unfavorable outcome at 6 months (43 vs. 48 %, P = 0.143) were comparable.

CONCLUSIONS

In Austria, the time of hospital admission has no influence on outcomes after severe TBI.

Effect of cocaine use on outcomes in traumatic brain injury

Context:

Animal and molecular studies have shown that cocaine exerts a neuroprotective effect against cerebral ischemia.

Aims:

To determine if the presence of cocaine metabolites on admission following traumatic brain injury (TBI) is associated with better outcomes.

Settings and Design:

Level-1 trauma center, retrospective cohort.

Materials and Methods:

After obtaining Institutional Review Board (IRB) approval, the trauma registry was searched from 2006 to 2009 for all patients aged 15-55 years with blunt head trauma and non-head AIS <3. Exclusion criteria were pre-existing brain pathology and death within 30 min of admission. The primary outcome was in-hospital mortality; secondary outcomes were hospital length of stay (LOS), and Glasgow Outcome Score (GOS).

Statistical Analysis:

Logistic regression was used to determine the independent effect of cocaine on mortality. Hospital LOS was compared with multiple linear regression.

Results:

A total of 741 patients met criteria and had drug screens. The screened versus unscreened groups were similar. Cocaine positive patients were predominantly African-American (46% vs. 21%, P < 0.0001), older (40 years vs. 30 years, P < 0.0001), and had ethanol present more often (50.7% vs. 37.8%, P = 0.01). There were no differences in mortality (cocaine-positive 1.4% vs. cocaine-negative 2.7%, P = 0.6) on both univariate and multivariate analysis.

Conclusions:

Positive cocaine screening was not associated with mortality in TBI. An effect may not have been detected because of the low mortality rate. LOS is affected by many factors unrelated to the injury and may not be a good surrogate for recovery. Similarly, GOS may be too coarse a measure to identify a benefit.

Redefining hypotension in traumatic brain injury

BACKGROUND

Systemic hypotension is a well documented predictor of increased mortality following traumatic brain injury (TBI). Hypotension is traditionally defined as systolic blood pressure (SBP)<90 mmHg. Recent evidence defines hypotension by a higher SBP in injured (non-TBI) trauma patients. We hypothesize that hypotension threshold requires a higher SBP in isolated moderate to severe TBI.

PATIENTS AND METHODS

A retrospective database review of all adults (≥ 15 years) with isolated moderate to severe TBI (head abbreviated injury score (AIS)≥ 3, all other AIS ≤ 3), admitted from five Level I and eight Level II trauma centres (Los Angeles County), between 1998 and 2005. Several fit statistic analyses were performed for each admission SBP from 60 to 180 mmHg to identify the model that most accurately defined hypotension for three age groups: 15-49 years, 50-69 years, and ≥ 70 years. The main outcome variable was mortality, and the optimal definition of hypotension for each group was determined from the best fit model. Adjusted odds ratios (AOR) were then calculated to determine increased odds in mortality for the defined optimal SBP within each age group.

RESULTS

A total of 15,733 patients were analysed. The optimal threshold of hypotension according to the best fit model was SBP of 110 mmHg for patients 15-49 years (AOR 1.98, CI 1.65-2.39, p<0.0001), 100 mmHg for patients 50-69 years (AOR 2.20, CI 1.46-3.31, p=0.0002), and 110 mmHg for patients ≥ 70 years (AOR 1.92, CI 1.35-2.74, p=0.0003).

CONCLUSIONS

Patients with isolated moderate to severe TBI should be considered hypotensive for SBP<110 mmHg. Further research should confirm this new definition of hypotension by correlation with indices of perfusion.

Alcohol use at time of injury and survival following traumatic brain injury: results from the National Trauma Data Bank

OBJECTIVE

Premised on biological evidence from animal research, recent clinical studies have, for the most part, concluded that elevated blood alcohol concentration levels are independently associated with higher survival or decreased mortality in patients with moderate to severe traumatic brain injury (TBI). This study aims to provide some counterevidence to this claim and to further future investigations.

METHOD

Incident data were drawn from the largest U.S. trauma registry, the National Trauma Data Bank, for emergency department admission years 2002-2006. TBI was identified according to the National Trauma Data Bank's definition using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), codes. To eliminate confounding, the exact matching method was used to match alcohol-positive with alcohol-negative incidents on sex, age, race/ethnicity, and facility. Logistic regression compared in-hospital mortality between 44,043 alcohol-positive and 59,817 matched alcohol-negative TBI incidents, with and without causes and intents of TBI and Injury Severity Score as covariates. A sensitivity analysis was performed within a subsample of isolated moderate to severe TBI incidents.

RESULTS

Alcohol use at the time of injury was found to be significantly associated with an increased risk for TBI. Including varied causes and intents of TBI and Injury Severity Score as potential confounders in the regression model explained away the statistical significance of the seemingly protective effect of alcohol against TBI mortality for all TBIs and for isolated moderate to severe TBIs.

CONCLUSIONS

The null finding shows that the purported reduction in TBI mortality attributed to positive blood alcohol likely is attributable to residual confounding. Accordingly, the risk of TBI associated with alcohol use should not be overlooked.

Correlating the Blood Alcohol Concentration with Outcome after Traumatic Brain Injury: Too Much Is Not a Bad Thing

Although recent evidence suggests a beneficial effect of alcohol for patients with traumatic brain injury (TBI), the level of alcohol that confers the protective effect is unknown. Our objective was to investigate the relationship between admission blood alcohol concentration (BAC) and outcomes in patients with isolated moderate to severe TBI. From 2005 to 2009, the Los Angeles County Trauma Database was queried for all patients ≥14 years of age with isolated moderate to severe TBI and admission serum alcohol levels. Patients were then stratified into four levels based on admission BAC: None (0 mg/dL), low (0-100 mg/dL), moderate (100-230 mg/dL), and high (≥230 mg/dL). Demographics, patient characteristics, and outcomes were compared across levels. In evaluating 3794 patients, the mortality rate decreased with increasing BAC levels (linear trend P < 0.0001). In determining the relationship between BAC and mortality, multivariable logistic regression analysis demonstrated a high BAC level was significantly protective (adjusted odds ratio 0.55; 95% confidence interval: 0.38-0.8; P = 0.002). In the largest study to date, a high (≥230 mg/dL) admission BAC was independently associated with improved survival in patients with isolated moderate to severe TBI. Additional research is warranted to investigate the potential therapeutic implications.

Ethanol intoxication is associated with a lower incidence of admission coagulopathy in severe traumatic brain injury patients

The aim of this study was to determine the impact of ethanol (ETOH) on the incidence of severe traumatic brain injury (sTBI)-associated coagulopathy and to examine the effect of ETOH on in-hospital outcomes in patients sustaining sTBI. Patients admitted to the surgical intensive care unit from June 2005 through December 2008 following sTBI, defined as a head Abbreviated Injury Scale (AIS) score ≥3, were retrospectively identified. Patients with a chest, abdomen, or extremity AIS score >3 were excluded to minimize the impact of extracranial injuries. Criteria for sTBI-associated coagulopathy included thrombocytopenia and/or elevated International Normalized Ratio (INR) and/or prolonged activated partial thromboplastin time (aPTT). The incidence of admission coagulopathy, in-hospital complications, and mortality were compared between patients who were ETOH positive [ETOH (+)] and ETOH negative [ETOH (-)]. During the study period, there were 439 patients with ETOH levels available for analysis. Overall, 46.5% (n=204) of these patients were ETOH (+), while 53.5% (n=235) were ETOH (-). Coagulopathy was significantly less frequent in the ETOH (+) patients compared to their ETOH (-) counterparts (5.4% versus 15.3%; adjusted p<0.001). In the forward logistic regression analysis, a positive ETOH level proved to be an independent protective factor for admission coagulopathy [OR (95% CI)=0.24 (0.10,0.54; p=0.001]. ETOH (+) patients had a significantly lower in-hospital mortality rate than ETOH (-) patients [9.8% versus 16.6%; adjusted p=0.011; adjusted OR (95% CI)=0.39 (0.19,0.81)]. For brain-injured patients arriving alive to the hospital, ETOH intoxication is associated with a significantly lower incidence of early coagulopathy and in-hospital mortality. Further research to establish the pathophysiologic mechanisms underlying any potential beneficial effect of ETOH on the coagulation system following sTBI is warranted.

Alcohol is associated with a lower pneumonia rate after traumatic brain injury

BACKGROUND

Recent evidence supports the beneficial effect of alcohol on patients with traumatic brain injury (TBI). Pneumonia is a known complication following TBI; thus, the purpose of this study was to evaluate the effects of alcohol on pneumonia rates following moderate to severe TBI.

METHODS

From 2005 to 2009, the Los Angeles County Trauma Database was queried for all patients ≥ 14 y of age with isolated moderate to severe TBI and admission serum alcohol levels. The incidence of pneumonia was compared between TBI patients with and without a positive blood alcohol concentration (BAC) level. The study population was then stratified into four BAC levels: None (0 mg/dL), low (0-100 mg/dL), moderate (100-230 mg/dL), and high (≥ 230 mg/dL). Pneumonia rates were compared across these levels.

RESULTS

A total of 3547 patients with isolated, moderate to severe TBI were evaluated. Nearly 66% tested positive for alcohol. The pneumonia rate was significantly lower in the TBI patients who tested positive for alcohol (2.5%) compared with those who tested negative (4.0%, P = 0.017). The pneumonia rate also decreased across increasing BAC levels (linear trend P = 0.03). After logistic regression analysis, a positive ethanol (ETOH) level was associated with a reduced incidence of pneumonia (AOR = 0.62; 95%CI: 0.41-0.93; P = 0.020).

CONCLUSION

A positive serum alcohol level was associated with a significantly lower pneumonia rate in isolated, moderate to severe TBI patients. This may explain the observed mortality reduction in TBI patients who test positive for alcohol. Additional research is warranted to investigate the potential therapeutic implications of this association.

Serum Ethanol Levels in Patients with Moderate to Severe Traumatic Brain Injury Influence Outcomes: A Surprising Finding

Animal studies routinely demonstrate an alcohol (ETOH) -mediated increase in survival after experimental traumatic brain injury (TBI). Recent clinical studies also suggest ETOH plays a neuroprotective role in moderate to severe TBI. We sought to investigate the relationship between ETOH and outcomes in patients with moderate to severe TBI using a countywide database. The Los Angeles County Trauma System database was queried for all adult (older than 14 years) patients with isolated moderate to severe TBI trauma (head Abbreviated Injury Score [AIS] 3 or greater, all other AIS 3 or less) who had ETOH levels measured on admission between 1998 and 2005. A total of 7304 patients were evaluated with 3219 (44.1%) patients testing positive for serum ETOH. ETOH-positive patients with TBI had a significantly lower mortality rate compared with ETOH negative patients (8.5 vs 10.5%, P = 0.005). Even after logistic regression analysis, a positive ETOH was associated with reduced mortality (adjusted OR 0.82, 95% CI: 0.69-0.99, P = 0.035). Therefore, a positive serum ETOH level was independently associated with significantly improved survival in patients with isolated moderate to severe TBI. The neuroprotective role ETOH plays in TBI is in contrast to previous findings and deserves further attention as a potential therapeutic.

Alcohol exposure and outcomes in trauma patients

Objective

To determine the injury patterns, complications, and mortality after alcohol consumption in trauma patients.

Methods

The Trauma Registry at an American College of Surgeons (ACS) level I center was queried for all patients with a toxicology screen admitted between 1st January 2002 and 31st December 2005. Alcohol-positive (AP) patients were matched to control patients who had a completely negative screen (AN) using age, gender, mechanism, Injury Severity Score (ISS), head Abbreviated Injury Scale (AIS), chest AIS, abdominal AIS, and extremity AIS. Injuries and outcomes were compared between the groups.

Results

As many as 5,317 patients had toxicology data, of which 471 (8.9%) had a positive alcohol screen (AP). A total of 386 AP patients were then matched to 386 control (AN) patients. The AP group had a significantly higher mortality than the AN group overall (23 vs. 13%; p < 0.001), and by ISS stratification: ISS < 16 (6 vs. 0.4%; p < 0.001), ISS 16–25 (53 vs. 28%; p = 0.01), and ISS > 25 (90 vs. 67%; p = 0.01). AP patients had a higher incidence of admission systolic blood pressure < 90 (18 vs. 10%; p < 0.001) and Glasgow Coma Scale (GCS) score ≤ 8 (25 vs. 17%; p = 0.002). AN patients had a significantly higher incidence of hemopneumothorax (11 vs. 7%; p = 0.03), while AP patients had a higher incidence of cardiac arrest (8 vs. 3%; p = 0.004). There was no difference in intensive care unit (ICU) and hospital length of stay.

Conclusion

In a mixed population of trauma patients, an AP screen is associated with an increased incidence of admission hypotension and depressed GCS score. In this case-matched study, alcohol exposure appeared to increase mortality after injury.