Early-Stage Hyperoxia Is Associated with Favorable Neurological Outcomes and Survival after Severe Traumatic Brain Injury: A Post-Hoc Analysis of the Brain Hypothermia Study

Clinical Insights and Future Directions in Hypothermia for Severe Traumatic Brain Injury: A Narrative Review

Fever control is essential in patients with severe traumatic brain injury (TBI). The efficacy of therapeutic hypothermia (TH) in severe TBI has been investigated over the last few decades; however, in contrast to experimental studies showing benefits, no evidence of efficacy has been demonstrated in clinical practice. In this review, the mechanisms and history of hypothermia were briefly outlined, while the results of major randomized controlled trials (RCTs) and meta-analyses investigating TH for adult TBI were introduced and discussed. The retrieved meta-analyses showed conflicting results, with a limited number of studies indicating the benefits of TH. Some studies have shown the benefits of long-term TH compared with short-term TH. Although TH is effective at lowering elevated intracranial pressure (ICP), reduced ICP does not lead to favorable outcomes. Low-quality RCTs overestimated the benefits of TH, while high-quality RCTs showed no difference or worse outcomes with TH. RCTs assessing standardized TH quality demonstrated the benefits of TH. As TBI has heterogeneous and complicated pathologies, applying a uniform treatment may not be ideal. A meta-analysis of young patients who underwent early cooling and hematoma removal showed better TH results. TH should not be abandoned, and its optimal usage should be advocated on an individual basis.

Effect of Different Early Oxygenation Levels on Clinical Outcomes of Patients Presenting in the Emergency Department With Severe Traumatic Brain Injury

STUDY OBJECTIVE

Despite the almost universal administration of supplemental oxygen in patients presenting in the emergency department (ED) with severe traumatic brain injury, optimal early oxygenation levels are unknown. Therefore, we aimed to examine the effect of different early oxygenation levels on the clinical outcomes of patients presenting in the emergency department with severe traumatic brain injury.

METHODS

We performed a secondary analysis of the Resuscitation Outcomes Consortium Traumatic Brain Injury Hypertonic Saline randomized controlled trial by including patients with Glasgow Coma Scale ≤8. Early oxygenation levels were assessed by the worst value of arterial partial pressure of oxygen (PaO₂) during the first 4 hours of presentation in the emergency department. The primary outcome was 6-month neurologic status, as assessed by the Extended Glasgow Outcome Scale. A binary logistic regression was utilized, and an odds ratio (OR) with 95% (95% confidence intervals) was calculated.

RESULTS

A total of 910 patients were included. In unadjusted (crude) analysis, a PaO₂ of 101 to 250 mmHg (OR, 0.59 [0.38 to 0.91]), or 251 to 400 mmHg (OR, 0.53 [0.34 to 0.83]) or ≥401 mmHg (OR, 0.31 [0.20 to 0.49]) was less likely to be associated with poor neurologic status when compared with a PaO₂ of ≤100 mmHg. This was also the case for adjusted analyses (including age, pupillary reactivity, and Revised Trauma Score).

CONCLUSION

High oxygenation levels as early as the first 4 hours of presentation in the emergency department may not be adversely associated with the long-term neurologic status of patients with severe traumatic brain injury. Therefore, during the early phase of trauma, clinicians may focus on stabilizing patients while giving low priority to the titration of oxygenation levels.

Temperature difference between jugular bulb and pulmonary artery is associated with neurological outcome in patients with severe traumatic brain injury: A post hoc analysis of a brain hypothermia study

BACKGROUND

The purpose of this study was to examine whether the temperature difference between the jugular bulb and pulmonary artery (ΔTjb-pa) is associated with the neurological outcome of patients with severe traumatic brain injury (TBI).

METHODS

We conducted a post hoc analysis of a multicenter randomized controlled trial of mild therapeutic hypothermia (TH, 32.0-34.0°C) or fever control (FC, 35.5-37.0°C) for the patients with severe TBI. ΔTjb-pa averaged every 12 h and the variation in ΔTjb-pa were compared between patients with favorable (n = 39) and unfavorable (n = 37) neurological outcomes. These values were also compared in the TH and FC subgroups.

RESULTS

The average ΔTjb-pa values in patients with favorable and unfavorable outcomes were 0.24 ± 0.23 and 0.06 ± 0.36°C, respectively (P < 0.001). ΔTjb-pa trended significantly higher in the favorable outcome patients than in the unfavorable outcome patients throughout the 120 h after onset of severe TBI (P < 0.001). The variation in ΔTjb-pa from 0 to 72 h was significantly lower in the favorable outcome patients than in the unfavorable outcome patients (0.8 ± 0.8 vs 1.8 ± 2.5°C, respectively, P = 0.013). From 72 to 120 h, there was no significant difference in the variation in ΔTjb-pa. Significant differences between patients with favorable and unfavorable outcomes in ΔTjb-pa and the variation in ΔTjb-pa were similar in the TH subgroup, but not evident in the FC subgroup.

CONCLUSIONS

A reduction in ΔTjb-pa and greater variation in ΔTjb-pa were associated with an unfavorable outcome in patients with severe TBI, especially those treated with TH. When treating severe TBI patients, it is important to understand that there will be differences in temperature reflecting the brain environment and the systemic temperature, depending on the severity and outcome of TBI during TH.

The Effect of Hyperoxemia on Neurological Outcomes of Adult Patients: A Systematic Review and Meta-Analysis

Hyperoxemia commonly occurs in clinical practice and is often left untreated. Many studies have shown increased mortality in patients with hyperoxemia, but data on neurological outcome in these patients are conflicting, despite worsened neurological outcome found in preclinical studies. To investigate the association between hyperoxemia and neurological outcome in adult patients, we performed a systematic review and meta-analysis of observational studies. We searched MEDLINE, Embase, Scopus, Web of Science, Cumulative Index to Nursing and Allied Health Literature, and ClinicalTrials.gov from inception to May 2020 for observational studies correlating arterial oxygen partial pressure (PaO₂) with neurological status in adults hospitalized with acute conditions. Studies of chronic pulmonary disease or hyperbaric oxygenation were excluded. Relative risks (RRs) were pooled at the study level by using a random-effects model to compare the risk of poor neurological outcome in patients with hyperoxemia and patients without hyperoxemia. Sensitivity and subgroup analyses and assessments of publication bias and risk of bias were performed. Maximum and mean PaO₂ in patients with favorable and unfavorable outcomes were compared using standardized mean difference (SMD). Of 6255 records screened, 32 studies were analyzed. Overall, hyperoxemia was significantly associated with an increased risk of poor neurological outcome (RR 1.13, 95% confidence interval [CI] 1.05-1.23, statistical heterogeneity I² 58.8%, 22 studies). The results were robust across sensitivity analyses. Patients with unfavorable outcome also showed a significantly higher maximum PaO₂ (SMD 0.17, 95% CI 0.04-0.30, I² 78.4%, 15 studies) and mean PaO₂ (SMD 0.25, 95% CI 0.04-0.45, I² 91.0%, 13 studies). These associations were pronounced in patients with subarachnoid hemorrhage (RR 1.34, 95% CI 1.14-1.56) and ischemic stroke (RR 1.41, 95% CI 1.14-1.74), but not in patients with cardiac arrest, traumatic brain injury, or following cardiopulmonary bypass. Hyperoxemia is associated with poor neurological outcome, especially in patients with subarachnoid hemorrhage and ischemic stroke. Although our study cannot establish causality, PaO₂ should be monitored closely because hyperoxemia may be associated with worsened patient outcome and consequently affect the patient's quality of life.

The Impact of Hyperoxia Treatment on Neurological Outcomes and Mortality in Moderate to Severe Traumatic Brain Injured Patients

Background

Traumatic brain injury is a leading cause of morbidity and mortality worldwide. The relationship between hyperoxia and outcomes in patients with TBI remains controversial. We assessed the effect of persistent hyperoxia on the neurological outcomes and survival of critically ill patients with moderate-severe TBI.

Method

This was a retrospective cohort study of all adults with moderate-severe TBI admitted to the ICU between 1st January 2016 and 31st December 2019 and who required invasive mechanical ventilation. Arterial blood gas data was recorded within the first 3 hours of intubation and then after 6-12 hours and 24-48 hours. The patients were divided into two categories: Group I had a PaO2 < 120mmHg on at least two ABGs undertaken in the first twelve hours post intubation and Group II had a PaO2 ≥ 120mmHg on at least two ABGs in the same period. Multivariable logistic regression was performed to assess predictors of hospital mortality and good neurologic outcome (Glasgow outcome score ≥ 4).

Results

The study included 309 patients: 54.7% (n=169) in Group I and 45.3% (n=140) in Group II. Hyperoxia was not associated with increased mortality in the ICU (20.1% vs. 17.9%, p=0.62) or hospital (20.7% vs. 17.9%, p=0.53), moreover, the hospital discharge mean (SD) Glasgow Coma Scale (11.0(5.1) vs. 11.2(4.9), p=0.70) and mean (SD) Glasgow Outcome Score (3.1(1.3) vs. 3.1(1.2), p=0.47) were similar. In multivariable logistic regression analysis, persistent hyperoxia was not associated with increased mortality (adjusted odds ratio [aOR] 0.71, 95% CI 0.34-1.35, p=0.29). PaO2 within the first 3 hours was also not associated with mortality: 121-200mmHg: aOR 0.58, 95% CI 0.23-1.49, p=0.26; 201-300mmHg: aOR 0.66, 95% CI 0.27-1.59, p=0.35; 301-400mmHg: aOR 0.85, 95% CI 0.31-2.35, p=0.75 and >400mmHg: aOR 0.51, 95% CI 0.18-1.44, p=0.20; reference: PaO2 60-120mmHg within 3 hours. However, hyperoxia >400mmHg was associated with being less likely to have good neurological (GOS ≥4) outcome on hospital discharge (aOR 0.36, 95% CI 0.13-0.98, p=0.046; reference: PaO2 60-120mmHg within 3 hours.

Conclusion

In intubated patients with moderate-severe TBI, hyperoxia in the first 48 hours was not independently associated with hospital mortality. However, PaO2 >400mmHg may be associated with a worse neurological outcome on hospital discharge.

Proper Partial Pressure of Arterial Oxygen for Patients with Traumatic Brain Injury

Background

The partial pressure of arterial oxygen (PaO₂) is critical to the outcome of patients with traumatic brain injury (TBI). However, it is not clear what range of PaO₂ should be maintained to improve patient outcome. The aim of this study was to explore the PaO₂ value needed in the acute phase of TBI and provide new evidence for clinical practice.

Material/Methods

A total of 153 patients with TBI were enrolled retrospectively. Univariate and multivariate logistic regression analyses were conducted on sex, Glasgow Coma Scale (GCS) score on admission, PaO₂ within 6 h of admission, oxygenation index, and other factors. The Glasgow Outcome Score (GOS) of the patient at discharge was used as an indicator of outcome. The good outcome group had GOS ≥4, and the poor outcome group had GOS <4.

Results

The 153 patients were divided into a good outcome group (n=62) and poor outcome group (n=91). There was a significant difference in sex, admission GCS, surgery, airway status, PaO₂, and oxygen index within 6 h of admission between the 2 groups. Logistic regression analysis showed that PaO₂ <60 mmHg, male sex, and admission GCS score of 3 to 12 were independent risk factors for a poor outcome.

Conclusions

Patients with TBI having PaO₂ <60 mmHg within 6 h after admission were more likely to have poor outcomes. The upper limit value of PaO₂ that affects the outcome of TBI in patients has not been found.

Association Between Hyperoxia, Supplemental Oxygen, and Mortality in Critically Injured Patients

Supplemental Digital Content is available in the text.

OBJECTIVES:

Hyperoxia is common among critically ill patients and may increase morbidity and mortality. However, limited evidence exists for critically injured patients. The objective of this study was to determine the association between hyperoxia and in-hospital mortality in adult trauma patients requiring ICU admission.

DESIGN, SETTING, AND PARTICIPANTS:

This multicenter, retrospective cohort study was conducted at two level I trauma centers and one level II trauma center in CO between October 2015 and June 2018. All adult trauma patients requiring ICU admission within 24 hours of emergency department arrival were eligible. The primary exposure was oxygenation during the first 7 days of hospitalization.

INTERVENTIONS:

None.

MEASUREMENTS AND MAIN RESULTS:

Primary outcome was in-hospital mortality. Secondary outcomes were hospital-free days and ventilator-free days. We included 3,464 critically injured patients with a mean age of 52.6 years. Sixty-five percent were male, and 66% had blunt trauma mechanism of injury. The primary outcome of in-hospital mortality occurred in 264 patients (7.6%). Of 226,057 patient-hours, 46% were spent in hyperoxia (oxygen saturation > 96%) and 52% in normoxia (oxygen saturation 90–96%). During periods of hyperoxia, the adjusted risk for mortality was higher with greater oxygen administration. At oxygen saturation of 100%, the adjusted risk scores for mortality (95% CI) at Fio₂ of 100%, 80%, 60%, and 50% were 6.4 (3.5–11.8), 5.4 (3.4–8.6), 2.7 (1.7–4.1), and 1.5 (1.1–2.2), respectively. At oxygen saturation of 98%, the adjusted risk scores for mortality (95% CI) at Fio₂ of 100%, 80%, 60%, and 50% were 7.7 (4.3–13.5), 6.3 (4.1–9.7), 3.2 (2.2–4.8), and 1.9 (1.4–2.7), respectively.

CONCLUSIONS:

During hyperoxia, higher oxygen administration was independently associated with a greater risk of mortality among critically injured patients. Level of evidence: Cohort study, level III.

Hyperoxemia and Cerebral Vasospasm in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Cerebral vasospasm is a major contributor to disability and mortality after aneurysmal subarachnoid hemorrhage. Oxidation of cell-free hemoglobin plays an integral role in neuroinflammation and is a suggested source of tissue injury after aneurysm rupture. This study sought to determine whether patients with subarachnoid hemorrhage and cerebral vasospasm were more likely to have been exposed to early hyperoxemia than those without vasospasm.

METHODS

This single-center retrospective cohort study included adult patients presenting with aneurysmal subarachnoid hemorrhage to Vanderbilt University Medical Center between January 2007 and December 2017. Patients with an ICD-9/10 diagnosis of aneurysmal subarachnoid hemorrhage were initially identified (N = 441) and subsequently excluded if they did not have intracranial imaging, arterial PaO₂ values or died within 96 h post-rupture (N = 96). The final cohort was 345 subjects. The degree of hyperoxemia was defined by the highest PaO₂ measured within 72 h after aneurysmal rupture. The primary outcome was development of cerebral vasospasm, which included asymptomatic vasospasm and delayed cerebral ischemia (DCI). Secondary outcomes were mortality and modified Rankin Scale.

RESULTS

Three hundred and forty five patients met inclusion criteria; 218 patients (63%) developed vasospasm. Of those that developed vasospasm, 85 were diagnosed with delayed cerebral ischemia (DCI, 39%). The average patient age of the cohort was 55 ± 13 years, and 68% were female. Ninety percent presented with Fisher grade 3 or 4 hemorrhage (N = 310), while 42% presented as Hunt-Hess grade 4 or 5 (N = 146). In univariable analysis, patients exposed to higher levels of PaO₂ by quintile of exposure had a higher mortality rate and were more likely to develop vasospasm in a dose-dependent fashion (P = 0.015 and P = 0.019, respectively). There were no statistically significant predictors that differentiated asymptomatic vasospasm from DCI and no significant difference in maximum PaO₂ between these two groups. In multivariable analysis, early hyperoxemia was independently associated with vasospasm (OR = 1.15 per 50 mmHg increase in PaO2 [1.03, 1.28]; P = 0.013), but not mortality (OR = 1.10 [0.97, 1.25]; P = 0.147) following subarachnoid hemorrhage.

CONCLUSIONS

Hyperoxemia within 72 h post-aneurysmal rupture is an independent predictor of cerebral vasospasm, but not mortality in subarachnoid hemorrhage. Hyperoxemia is a variable that can be readily controlled by adjusting the delivered FiO₂ and may represent a modifiable risk factor for vasospasm.

Systematic review of oxygenation and clinical outcomes to inform oxygen targets in critically ill trauma patients

BACKGROUND

Oxygen therapy is frequently administered to critically ill trauma patients to avoid hypoxia, but optimal oxygenation strategies are not clear.

METHODS

We conducted a systematic review of oxygen targets and clinical outcomes in trauma and critically ill patients. We searched Ovid MEDLINE, Cochrane Library, Embase, and Web of Science Core Collection from 1946 through 2017. Our initial search yielded 14,774 articles with 209 remaining after abstract review. We reviewed full text articles of human subjects with conditions of interest, an oxygen exposure or measurement, and clinical outcomes, narrowing the review to 43 articles. We assessed article quality using Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

Of the 43 final studies meeting inclusions criteria, 17 focused on trauma and 26 studies focused on medical and/or surgical critical illness without trauma specifically. Four trauma studies supported lower oxygenation/normoxia, two supported higher oxygenation, and 11 supported neither normoxia nor higher oxygenation (five neutral and six supported avoidance of hypoxia). Fifteen critical illness studies supported lower oxygenation/normoxia, one supported higher oxygenation, and 10 supported neither normoxia nor higher oxygenation (nine neutral and one supported avoidance of hypoxia). We identified seven randomized controlled trials (four high quality, three moderate quality). Of the high-quality randomized controlled trials (none trauma-related), one supported lower oxygenation/normoxia and three were neutral. Of the moderate-quality randomized controlled trials (one trauma-related), one supported higher oxygenation, one was neutral, and one supported avoidance of hypoxia.

CONCLUSION

We identified few trauma-specific studies beyond traumatic brain injury; none were high quality. Extrapolating primarily from nontrauma critical illness, reduced oxygen administration targeting normoxia in critically ill trauma patients may result in better or equivalent clinical outcomes. Additional trauma-specific trials are needed to determine the optimal oxygen strategy in critically injured patients.

LEVEL OF EVIDENCE

Systematic review, level IV.

High early phase hemoglobin level is associated with favorable neurological outcome in patients with severe traumatic brain injury

BACKGROUND

The appropriate hemoglobin (Hb) level threshold for the early phase (i.e. from Emergency Department to ICU admission) in patients with severe traumatic brain injury (TBI) is still unknown. Therefore, we aimed to examine the association between Hb levels during the early phase and neurological outcomes in patients with severe TBI using data from the Brain Hypothermia (B-HYPO) Study Group.

METHODS

We performed a post-hoc analysis of the B-HYPO study (a prospective, multicenter, randomized controlled trial on patients with severe TBI who received either mild therapeutic hypothermia [MTH; 32.0 °C-34.0 °C] or fever control [35.5 °C-37.0 °C]). We calculated Hb levels during early phase by the formula: (admission Hb + Hb on day 1) / 2. The primary outcome was the association between during early phase Hb levels and 6-month neurological outcome after the TBI based on the Glasgow Outcome Scale scores (a measure of functional recovery defined as moderate disability or good recovery).

RESULTS

We reviewed data from 130 patients and found favorable neurological outcomes in 48.5% of them. We found significant differences between the favorable and unfavorable neurological outcome groups in terms of their Hb levels on admission and on day 1. But, we found no Hb level differences after day 3 (including 1 day after rewarming). Our multivariable analysis showed that Hb levels during early phase were significantly associated with favorable neurological outcomes (odds ratio, 1.387; 95% confidence interval, 1.057-1.858; P = 0.018).

CONCLUSIONS

High early phase Hb levels are associated with favorable neurological outcomes after severe TBI.

The effect of hyperoxia on mortality in critically ill patients: a systematic review and meta analysis

Background

Studies investigating the role of hyperoxia in critically ill patients have reported conflicting results. We did this analysis to reveal the effect of hyperoxia in the patients admitted to the intensive care unit (ICU).

Methods

Electronic databases were searched for all the studies exploring the role of hyperoxia in adult patients admitted to ICU. The primary outcome was mortality. Random-effect model was used for quantitative synthesis of the adjusted odds ratio (aOR).

Results

We identified 24 trials in our final analysis. Statistical heterogeneity was found between hyperoxia and normoxia groups in patients with mechanical ventilation (I² = 92%, P < 0.01), cardiac arrest(I² = 63%, P = 0.01), traumatic brain injury (I² = 85%, P < 0.01) and post cardiac surgery (I² = 80%, P = 0.03). Compared with normoxia, hyperoxia was associated with higher mortality in overall patients (OR 1.22, 95% CI 1.12~1.33), as well as in the subgroups of cardiac arrest (OR 1.30, 95% CI 1.08~1.57) and extracorporeal life support (ELS) (OR 1.44, 95% CI 1.03~2.02).

Conclusions

Hyperoxia would lead to higher mortality in critically ill patients especially in the patients with cardiac arrest and ELS.

Electronic supplementary material

The online version of this article (10.1186/s12890-019-0810-1) contains supplementary material, which is available to authorized users.

Oxygen Treatment in Intensive Care and Emergency Medicine

BACKGROUND

Oxygen treatment is often life-saving, but multiple studies in recent years have yielded evidence that the indiscriminate administration of oxygen to patients in the intensive care unit and emergency room can cause hyperoxia and thereby elevate mortality.

METHODS

This review is based on prospective, randomized trials concerning the optimum use of oxygen in adult medicine, which were retrieved by a selective search in PubMed, as well as on pertinent retrospective studies and guideline recommendations.

RESULTS

13 prospective, randomized trials involving a total of 17 213 patients were analyzed. In patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) and in ventilated intensive-care patients, normoxia was associated with a lower mortality than hyperoxia (2% vs. 9%). In patients with myocardial infarction, restrictive oxygen administration was associated with a smaller infarct size on cardiac MRI at 6 months compared to oxygen administration at 8 L/min (13.1 g vs. 20.3 g). For patients with stroke, the currently available data do not reveal any benefit or harm from oxygen administration. None of the trials showed any benefit from the administration of oxygen to non-hypoxemic patients; in fact, this was generally associated with increased morbidity or mortality.

CONCLUSION

Hypoxemia should certainly be avoided, but the fact that the liberal administration of oxygen to patients in intensive care units and emergency rooms tends to increase morbidity and mortality implies the advisability of a conservative, normoxic oxygenation strategy.

A pilot study of hyperoxemia on neurological injury, inflammation and oxidative stress

BACKGROUND

Normobaric hyperoxia is used to alleviate secondary brain ischaemia in patients with traumatic brain injury (TBI), but clinical evidence is limited and hyperoxia may cause adverse events.

METHODS

An open label, randomised controlled pilot study comparing blood concentrations of reactive oxygen species (ROS), interleukin 6 (IL-6) and neuron-specific enolase (NSE) between two different fractions of inspired oxygen in severe TBI patients on mechanical ventilation.

RESULTS

We enrolled 27 patients in the Fi O₂ 0.40 group and 38 in the Fi O₂ 0.70 group; 19 and 23 patients, respectively, completed biochemical analyses. In baseline, there were no differences between Fi O₂ 0.40 and Fi O₂ 0.70 groups, respectively, in ROS (64.8 nM [22.6-102.1] vs. 64.9 nM [26.8-96.3], P = 0.80), IL-6 (group 92.4 pg/ml [52.9-171.6] vs. 94.3 pg/ml [54.8-133.1], P = 0.52) or NSE (21.04 ug/l [14.0-30.7] vs. 17.8 ug/l [14.1-23.9], P = 0.35). ROS levels did not differ at Day 1 (24.2 nM [20.6-33.5] vs. 29.2 nM [22.7-69.2], P = 0.10) or at Day 2 (25.4 nM [21.7-37.4] vs. 47.3 nM [34.4-126.1], P = 0.95). IL-6 concentrations did not differ at Day 1 (112.7 pg/ml [65.9-168.9) vs. 83.9 pg/ml [51.8-144.3], P = 0.41) or at Day 3 (55.0 pg/ml [34.2-115.6] vs. 49.3 pg/ml [34.4-126.1], P = 0.95). NSE levels did not differ at Day 1 (15.9 ug/l [9.0-24.3] vs. 15.3 ug/l [12.2-26.3], P = 0.62). There were no differences between groups in the incidence of pulmonary complications.

CONCLUSION

Higher fraction of inspired oxygen did not increase blood concentrations of markers of oxidative stress, inflammation or neurological injury or the incidence of pulmonary complications in severe TBI patients on mechanical ventilation.

iTRAQ-Based Quantitative Proteomics Reveals the New Evidence Base for Traumatic Brain Injury Treated with Targeted Temperature Management

This study aimed to investigate the effects of targeted temperature management (TTM) modulation on traumatic brain injury (TBI) and the involved mechanisms using quantitative proteomics technology. SH-SY5Y and HT-22 cells were subjected to moderate stretch injury using the cell injury controller (CIC), followed by incubation at TTM (mild hypothermia, 32°C), or normothermia (37°C). The real-time morphological changes, cell cycle phase distribution, death, and cell viability were evaluated. Moderate TBI was produced by the controlled cortical impactor (CCI), and the effects of TTM on the neurological damage, neurodegeneration, cerebrovascular histopathology, and behavioral outcome were determined in vivo. Results showed that TTM treatment prevented TBI-induced neuronal necrosis in the brain, achieved a substantial reduction in neuronal death both in vitro and in vivo, reduced cortical lesion volume and neuronal loss, attenuated cerebrovascular histopathological damage, brain edema, and improved behavioral outcome. Using an iTRAQ proteomics approach, proteins that were significantly associated with TTM in experimental TBI were identified. Importantly, changes in four candidate molecules (plasminogen [PLG], antithrombin III [AT III], fibrinogen gamma chain [FGG], transthyretin [TTR]) were verified using TBI rat brain tissues and TBI human cerebrospinal fluid (CSF) samples. This study is one of the first to investigate the neuroprotective effects of TTM on the proteome of human and experimental models of TBI, providing an overall landscape of the TBI brain proteome and a scientific foundation for further assessment of candidate molecules associated with TTM for the promotion of reparative strategies post-TBI.