Managing Severe Traumatic Brain Injury Across Resource Settings: Latin American Perspectives.

Severe traumatic brain injury (sTBI) is a condition of increasing epidemiologic concern worldwide. Outcomes are worse as observed in low- and middle-income countries (LMICs) versus high-income countries. Global targets are in place to address the surgical burden of disease. At the same time, most of the published literature and evidence on the clinical approach to sTBI comes from wealthy areas with an abundance of resources. The available paradigms, including the Brain Trauma Foundation guidelines, the Seattle International Severe Traumatic Brain Injury Consensus Conference, Consensus Revised Imaging and Clinical Examination, and multimodality approaches, may fit differently depending on local resources, expertise, and sociocultural factors. A first step toward addressing heterogeneity in practice is to consider comparative effectiveness approaches that can capture actual practice patterns and record short-term and long-term outcomes of interest. Decompressive craniectomy (DC) decreases intracranial pressure burden and can be lifesaving. Nevertheless, completed randomized controlled trials took place within high-income settings, leaving important questions unanswered and making extrapolations to LMICs questionable. The concept of preemptive DC specifically to address limited neuromonitoring resources may warrant further study to establish a benefit/risk profile for the procedure and its role within local protocols of care.

How to manage traumatic brain injury without invasive monitoring?

PURPOSE OF REVIEW: Severe traumatic brain injury (TBI) is an extremely serious health problem, especially in low-middle income countries (LMICs). The prevalence of severe TBI continues to increase in LMICs. Major limitations in the chain of care for TBI patients are common in LMICs including suboptimal or nonexistent prehospital care, overburdened emergency services, lack of trained human resources and limited availability of ICUs. Basic neuromonitoring, such as intracranial pressure, are unavailable or underutilized and advanced techniques are not available. RECENT FINDINGS: Attention to fundamental principles of TBI care in LMICs, including early categorization, prevention and treatment of secondary insults, use of low-cost technology for evaluation of intracranial bleeding and neuromonitoring, and emphasis on education of human resources and multidisciplinary work, are particularly important in LMICs. Institutional collaborations between high-income and LMICs have developed evidence focused on available resources. Accordingly, an expert group have proposed consensus recommendations for centers without availability of invasive brain monitoring. SUMMARY: Severe TBI is very prevalent in LMIC and neuromonitoring is often not available in these environments. When intracranial pressure monitors are not available, careful attention to changes on clinical examination, serial imaging and noninvasive monitoring techniques can help recognize intracranial hypertension and effectively guide treatment decisions.

Green, yellow or black? Genetic differentiation and adaptation signatures in a highly migratory marine turtle.

Marine species may exhibit genetic structure accompanied by phenotypic differentiation related to adaptation despite their high mobility. Two shape-based morphotypes have been identified for the green turtle (Chelonia mydas) in the Pacific Ocean: the south-central/western or yellow turtle and north-central/eastern or black turtle. The genetic differentiation between these morphotypes and the adaptation of the black turtle to environmentally contrasting conditions of the eastern Pacific region has remained a mystery for decades. Here we addressed both questions using a reduced-representation genome approach (Dartseq; 9473 neutral SNPs) and identifying candidate outlier loci (67 outlier SNPs) of biological relevance between shape-based morphotypes from eight Pacific foraging grounds (n = 158). Our results support genetic divergence between morphotypes, probably arising from strong natal homing behaviour. Genes and enriched biological functions linked to thermoregulation, hypoxia, melanism, morphogenesis, osmoregulation, diet and reproduction were found to be outliers for differentiation, providing evidence for adaptation of C. mydas to the eastern Pacific region and suggesting independent evolutionary trajectories of the shape-based morphotypes. Our findings support the evolutionary distinctness of the enigmatic black turtle and contribute to the adaptive research and conservation genomics of a long-lived and highly mobile vertebrate.

Outcomes of Nonagenarians with Acute Ischemic Stroke Treated with Intravenous Thrombolytics.

BACKGROUND: Nonagenarians are under-represented in thrombolytic trials for acute ischemic stroke (AIS). The effectiveness of intravenous thrombolytics in nonagenarians in terms of safety and outcome is not well established. MATERIALS AND METHODS: We used a multinational registry to identify patients aged 90 years or older with good baseline functional status who presented with AIS. Differences in outcomes-disability level at 90 days, frequency of symptomatic intracerebral hemorrhage (sICH), and mortality-between patients who did and did not receive thrombolytics were assessed using multivariable logistic regression, adjusted for prespecified prognostic factors. Coarsened exact matching (CEM) was utilized before evaluating outcome by balancing both groups in the sensitivity analysis. RESULTS: We identified 227 previously independent nonagenarians with AIS; 122 received intravenous thrombolytics and 105 did not. In the unmatched cohort, ordinal analysis showed a significant treatment effect (adjusted common odds ratio [OR]: .61, 95% confidence interval [CI]: .39-.96). There was an absolute difference of 8.1% in the rate of excellent outcome in favor of thrombolysis (17.4% versus 9.3%; adjusted ratio: .30, 95% CI: .12-.77). Rates of sICH and in-hospital mortality were not different. Similarly, in the matched cohort, CEM analysis showed a shift in the primary outcome distribution in favor of thrombolysis (adjusted common OR: .45, 95% CI: .26-.76). CONCLUSIONS: Nonagenarians treated with thrombolytics showed lower stroke-related disability at 90 days than those not treated, without significant difference in sICH and in-hospital mortality rates. These observations cannot exclude a residual confounding effect, but provide evidence that thrombolytics should not be withheld from nonagenarians because of age alone.

Clinical Course and Outcomes of Small Supratentorial Intracerebral Hematomas.

BACKGROUND AND PURPOSE: Intracerebral hemorrhage (ICH) volume, particularly if ≥30 mL, is a major determinant of poor outcome. We used a multinational ICH data registry to study the characteristics, course, and outcomes of supratentorial hematomas with volumes <30 mL. METHODS: Basic characteristics, clinical and radiological course, and 30-day outcomes of these patients were recorded. Outcomes were categorized as early neurological deterioration (END), hematoma expansion, Glasgow Outcome Scale (GOS), and in-hospital death. Poor outcome was defined as composite of in-hospital death and severe disability (GOS ≤ 3). Comparison was conducted based on hemorrhage location. Logistic regression using dichotomized outcome scales was applied to determine predictors of poor outcome. RESULTS: Among 375 cases of supratentorial ICH with volumes <30 mL, expansion and END rates were 19.2% and 7.5%, respectively. Hemorrhage growth was independently associated with END (odds ratio: 28.7, 95% confidence interval [CI]: 8.51-96.5; P < .0001). Expansion rates did not differ according to ICH location. Overall, 13.9% (exact binomial 95% CI: 10.5-17.8) died in the hospital and 29.1% (CI: 24.5-34.0) had severe disability at 30 days; there was a cumulative poor outcome rate of 42.9% (CI: 37.9-48.1). Age, admission Glasgow Coma Scale, intraventricular extension, and END were independently associated with poor outcome. There was no difference in poor outcome rates between lobar and deep locations (40.2% versus 43.8%, P = .56). CONCLUSION: Patients with supratentorial ICH <30 mL have high rates of poor outcome at 30 days, regardless of location. Nearly 1 in 5 hematomas <30 mL expands, leading to END or death.

Prior Cannabis Use Is Associated with Outcome after Intracerebral Hemorrhage.

OBJECTIVE: Recent evidence suggests that a potential harmful relationship exists between cannabis use and ischemic stroke. The purpose of this study was to determine the implications of cannabis use in intracerebral hemorrhage (ICH) patients. METHODS: An analysis of an international, multicenter, observational database of consecutive patients with spontaneous ICH was conducted. We extracted the following characteristics on presentation: demographics, risk factors, antiplatelet or anticoagulant use, Glasgow Coma Scale, ICH score, neuroimaging parameters, and urine toxicology screen (UTS) results. Modified Rankin Scale (mRS) score was utilized for determination of outcome at discharge. Adjusted logistic ordinal regression was used as shift analysis to assess the impact of cannabis use on mRS score at discharge. The adjusted common OR measured the likelihood that cannabis use would lead to lower mRS scores. RESULTS: Within a cohort of 725 spontaneous ICH patients, UTS was positive for cannabinoids in 8.6%. Cannabinoids-positive (CB+) patients were more frequently Caucasian (p < 0.001), younger (p < 0.001), and had lower median ICH scores on admission (p = 0.017) than those who were cannabinoids-negative. CB+ patients also showed a shift toward better outcome in the distribution of mRS categories, with an adjusted common OR of 0.544 (95% CI 0.330-0.895, p = 0.017). CONCLUSION: In this multinational cohort, cannabis use was discovered in nearly 10% of patients with spontaneous ICH. Although there was no relationship between cannabis use and specific ICH characteristics, CB+ patients had milder ICH presentation and less disability at discharge.

Glucose control in acute brain injury: does it matter?

PURPOSE OF REVIEW: Alterations of blood glucose levels are secondary insults with detrimental consequences for the injured brain. Here, we review various aspects of brain glucose metabolism and analyze the evidence on glycemic control during acute brain injury. RECENT FINDINGS: An essential component in the overall management of acute brain injury, especially during the acute phase, is maintaining adequate and appropriate control of serum glucose. This is one of the few physiological parameters that is modifiable. Hypoglycemia should be rigorously avoided. However, intensive insulin therapy is associated with unacceptable rates of hypoglycemia and metabolic crisis, and does not necessarily provide benefit. Hyperglycemia is harmful to the injured brain as it compromises microcirculatory blood flow, increases blood-brain barrier permeability, and promotes inflammation. In addition, it triggers osmotic diuresis, hypovolemia, and immunosuppression. SUMMARY: Glucose is the primary energy substrate for the brain. During injury, the brain increases its needs and is vulnerable to glucose deficit. In these situations, alternative fuel can be lactate, which has potential implications for future research. In this review, various pathophysiological aspects of glucose metabolism during acute brain injury, as well as the risks, causes, and consequences of glucose deficiency or excess, will be discussed.

Early Hypoalbuminemia is an Independent Predictor of Mortality in Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Hypoalbuminemia has been identified as a predictor of morbidity and mortality in critically ill patients. There is very little data on the significance and the prognostic value of hypoalbuminemia in patients with aneurysmal subarachnoid hemorrhage (aSAH). This study analyzed the impact of hypoalbuminemia on patient presentation, complications, and outcomes. METHODS: Records of patients admitted with aSAH were examined. Data on baseline characteristics, prevalence of delayed cerebral ischemia, and discharge outcomes were collected. Multivariable logistic regression analysis was performed to assess for associations. RESULTS: One-hundred and forty-two patients comprised the study cohort (mean age 54.6 ± 13.4), among which 45 (31.5 %) presented with hypoalbuminemia. No difference in baseline characteristics was noted between patients with hypoalbuminemia and those with normal serum albumin. The overall hospital mortality rate was significantly higher in patients with hypoalbuminemia, compared to those with normal albumin (28.9 % vs. 11.3 %; p = 0.04). Hypoalbuminemia was neither associated with delayed cerebral ischemia nor disability at discharge, but independently associated with in-hospital death (odds ratio: 4.26, 95 % confidence interval: 1.09-16.68; p = 0.04). CONCLUSION: In patients with aSAH, early hypoalbuminemia is an independent predictor of hospital mortality but not disability at discharge.

Doing More with Less on Intracranial Pressure Monitoring.

BACKGROUND: Intracranial pressure (ICP) management based on predetermined thresholds is not accurate in light of recent research on cerebrovascular physiology. Interpersonal and intrapersonal variations will lead ICP elevations to reach individualized thresholds for intracranial compliance impairment from one subject to another. Therefore reuniting the modern techniques of neuromonitoring besides ICP enables practitioners to have a more whole picture in anticipating neuro worsening and improving timing in decision making. METHODS: Brief literature review. RESULTS: For the severely brain-injured patient, current evidence indicates a personalized and physiology-based multimodal monitoring care to be required rather than decision making according to ICP predetermined cut-offs. CONCLUSIONS: The authors' point of view is of particular importance for regions with resource heterogeneity and scarcity, where ICP monitoring is not available for all those in need and noninvasive techniques may provide a surrogate approach. If physicians who deal with acute-brain-injured patients in lower-resource areas understand that several tools besides ICP may improve their practice, it is possible to reduce acute brain injury morbimortality.

New insight into the swimming kinematics of wild Green sea turtles (Chelonia mydas).

Biomechanically, sea turtles could be perceived as birds of the ocean as they glide and flap their forelimbs to produce the necessary forces required for locomotion, making sea turtles an interesting animal to study. However, being an endangered species makes studying the sea turtle's biomechanics a complex problem to solve, both technically and ethically, without causing disturbance. This work develops a novel, non-invasive procedure to develop full three-dimensional kinematics for wild sea turtles by filming the animals in Australia's Great Barrier Reef using underwater drones without disturbing them. We found that the wild animals had very different swimming patterns than previous studies on juveniles in captivity. Our findings show that the flipper goes through a closed-loop trajectory with extended sweeping of the flipper tip towards the centre of the carapace to create a clapping motion. We have named this the "sweep stroke" and in contrast to previously described four-stage models, it creates a five-stage cycle swimming locomotion model. The model presented here could lead to a better comprehension of the sea turtle propulsion methods and their fluid-structure interaction.

Neurological and Systemic Manifestations of Severe Scorpion Envenomation.

Scorpion envenomation is a life-threatening toxicological emergency and considered as a major public health problem, especially in endemic regions (India, Africa, Latin America); it is generally characterized by low resources and tropical or subtropical weather. Scorpion envenomation is especially fatal in the first hours, usually due to respiratory and/or cardiovascular collapse. The neurologic manifestations, triggered by multiple neurotoxic mechanisms, are varied and complex and mostly reported in children. The aim of this review is to clarify the epidemiologic characteristics and clinical manifestations as well as diagnosis and management of neurologic complications following scorpion envenomation. The management of patients with severe clinical forms is based on early recognition of the sting, antivenom serum administration, and cardiorespiratory and systemic support.

Treating hyperglycemia in neurocritical patients: benefits and perils.

There is growing debate over the value of intensive insulin therapy (IIT) in critically ill patients. Available trials have been performed in general medical or surgical intensive care units, and the results may not be directly applicable to patients with severe acute brain disease because these patients may have heightened susceptibility to hyperglycemia (HyperG) and hypoglycemia. Our objective was to review the pathophysiology and effects of HyperG and hypoglycemia in neurocritical patients and to analyze the potential role of IIT in this population. Source data were obtained from a PubMed search of the medical literature combining the terms HyperG, hypoglycemia, insulin, stroke, intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), traumatic brain injury (TBI), spinal cord injury (SCI), and related diagnoses. Brain metabolism is highly dependent on constant supply of glucose. As a consequence, the acutely injured brain is particularly sensitive to hypoglycemia, which can induce a state of energy failure (metabolic crisis). Meanwhile, neurocritical patients have a high prevalence of HyperG, and its occurrence is associated with poor outcome after acute ischemic stroke, ICH, SAH, and TBI. It is unclear whether this association is due to direct detrimental effects exerted by HyperG or simply represents a marker of severe brain injury. Insulin has been shown to have various potentially pleiotropic neuroprotective properties in experimental models. However, the safety and efficacy of IIT in patients with critical brain disease have not been well studied. Available results do not support the use of IIT to maintain strict normoglycemia in this population. Patients with critical brain disease should have frequent glucose monitoring because severe HyperG and even modest hypoglycemia may be detrimental. Careful use of insulin infusion protocols appears advisable, but maintenance of strict normoglycemia cannot be recommended. Rigorous studies must be conducted to assess the value of insulin therapy and to determine the optimal blood glucose targets in patients with the most common acute vascular and traumatic brain insults.

International consensus on the monitoring of cerebral oxygen tissue pressure in neurocritical patients. / Consenso internacional sobre la monitorización de la presión tisular cerebral de oxígeno en pacientes neurocríticos.

Continuous monitoring of cerebral oxygenation and its application to the management of the severe neurological patient is a challenge for the management of patients with acute critical brain damage. Although several techniques have been described for monitoring brain, brain tissue oxygen monitoring provides relevant information about oxygen levels of brain tissue. However, the development of this technique has been associated with the need to answer not only some technical aspects of it as well as the meaning of the changes of the cerebral oxygenation in the neurocritical patient. The consensus document responds to various questions related to the monitoring of cerebral oxygenation by means of a cerebral oxygen tissue pressure sensor. For this purpose, a list of questions was prepared and a reviewed of the medical literature was made. The quality of the evidence and the degree of recommendation was evaluated using the GRADE methodology.

Recommendations of the Colombian Consensus Committee for the Management of Traumatic Brain Injury in Prehospital, Emergency Department, Surgery, and Intensive Care (Beyond One Option for Treatment of Traumatic Brain Injury: A Stratified Protocol [BOOTStraP]).

Background Traumatic brain injury (TBI) is a global public health problem. In Colombia, it is estimated that 70% of deaths from violence and 90% of deaths from road traffic accidents are TBI related. In the year 2014, the Ministry of Health of Colombia funded the development of a clinical practice guideline (CPG) for the diagnosis and treatment of adult patients with severe TBI. A critical barrier to the widespread implementation was identified-that is, the lack of a specific protocol that spans various levels of resources and complexity across the four treatment phases. The objective of this article is to present the process and recommendations for the management of patients with TBI in various resource environments, across the treatment phases of prehospital care, emergency department (ED), surgery, and intensive care unit. Methods Using the Delphi methodology, a consensus of 20 experts in emergency medicine, neurosurgery, prehospital care, and intensive care nationwide developed recommendations based on 13 questions for the management of patients with TBI in Colombia. Discussion It is estimated that 80% of the global population live in developing economies where access to resources required for optimum treatment is limited. There is limitation for applications of CPGs recommendations in areas where there is low availability or absence of resources for integral care. Development of mixed methods consensus, including evidence review and expertise points of good clinical practices can fill gaps in application of CPGs. BOOTStraP (Beyond One Option for Treatment of Traumatic Brain Injury: A Stratified Protocol) is intended to be a practical handbook for care providers to use to treat TBI patients with whatever resources are available. Results Stratification of recommendations for interventions according to the availability of the resources on different stages of integral care is a proposed method for filling gaps in actual evidence, to organize a better strategy for interventions in different real-life scenarios. We develop 10 algorithms of management for building TBI protocols based on expert consensus to articulate treatment options in prehospital care, EDs, neurological surgery, and intensive care, independent of the level of availability of resources for care.

Consensus-Based Management Protocol (CREVICE Protocol) for the Treatment of Severe Traumatic Brain Injury Based on Imaging and Clinical Examination for Use When Intracranial Pressure Monitoring Is Not Employed.

Globally, intracranial pressure (ICP) monitoring use in severe traumatic brain injury (sTBI) is inconsistent and susceptible to resource limitations and clinical philosophies. For situations without monitoring, there is no published comprehensive management algorithm specific to identifying and treating suspected intracranial hypertension (SICH) outside of the one ad hoc Imaging and Clinical Examination (ICE) protocol in the Benchmark Evidence from South American Trials: Treatment of Intracranial Pressure (BEST:TRIP) trial. As part of an ongoing National Institutes of Health (NIH)-supported project, a consensus conference involving 43 experienced Latin American Intensivists and Neurosurgeons who routinely care for sTBI patients without ICP monitoring, refined, revised, and augmented the original BEST:TRIP algorithm. Based on BEST:TRIP trial data and pre-meeting polling, 11 issues were targeted for development. We used Delphi-based methodology to codify individual statements and the final algorithm, using a group agreement threshold of 80%. The resulting CREVICE (Consensus REVised ICE) algorithm defines SICH and addresses both general management and specific treatment. SICH treatment modalities are organized into tiers to guide treatment escalation and tapering. Treatment schedules were developed to facilitate targeted management of disease severity. A decision-support model, based on the group's combined practices, is provided to guide this process. This algorithm provides the first comprehensive management algorithm for treating sTBI patients when ICP monitoring is not available. It is intended to provide a framework to guide clinical care and direct future research toward sTBI management. Because of the dearth of relevant literature, it is explicitly consensus based, and is provided solely as a resource (a "consensus-based curbside consult") to assist in treating sTBI in general intensive care units in resource-limited environments.

Did the introduction of comprehensive stroke centers impact the "weekend effect" on mortality for patients with intracranial hemorrhage in the United States?

OBJECTIVES: Over the last two decades, various studies have evaluated the impact of weekend admission to the hospital on inpatient mortality. Our study sought to identify whether or not the "weekend effect" was true for patients with Intracranial Hemorrhage (ICH) admitted to United States hospitals and whether or not the introduction of comprehensive stroke centers (CSCs) made an impact on the "weekend effect" for ICH. PATIENTS AND METHODS: Searched the Nationwide Inpatient Sample for the ICH discharges between 2006 and 2014. Multivariate regression analysis was performed to evaluate the factors that impacted in-hospital mortality. Additional subgroup analysis was performed based on two time periods, before CSCs (2006-2009) and afterward (2010-2014). RESULTS: 146,587 discharges with ICH were reported by the NIS with 37,471 (25.6%) weekend admissions. The weekday admission cohort was 50.6% male with a mean age of 67.1 years. There was a total of 35,362 deaths among ICH admissions. The in-hospital mortality rate was significantly higher for weekend admissions compared to that of weekday admissions (25.2% vs. 23.8%, p < 0.001). Multivariate analysis of mortality for the 2006-2009 subgroup demonstrated a statistically significant higher odds of death with weekend admission (OR = 1.15, 95% CI [1.10, 1.20], p = 0) but not for the 2010-2014 subgroup (OR = 1.03, 95% CI [0.99, 1.07], p = 0.09). CONCLUSION: Our study showed that in-hospital mortality was found to be increased for patients with ICH admitted on a weekend; however, this association was lost after the initiation of CSCs. Further prospective studies are warranted to gain a better understanding regarding this association.

Identifying genetic lineages through shape: An example in a cosmopolitan marine turtle species using geometric morphometrics.

The green turtle (Chelonia mydas) is a globally distributed marine species whose evolutionary history has been molded by geological events and oceanographic and climate changes. Divergence between Atlantic and Pacific clades has been associated with the uplift of the Panama Isthmus, and inside the Pacific region, a biogeographic barrier located west of Hawaii has restricted the gene flow between Central/Eastern and Western Pacific populations. We investigated the carapace shape of C. mydas from individuals of Atlantic, Eastern Pacific, and Western Pacific genetic lineages using geometric morphometrics to evaluate congruence between external morphology and species' phylogeography. Furthermore, we assessed the variation of carapace shape according to foraging grounds. Three morphologically distinctive groups were observed which aligned with predictions based on the species' lineages, suggesting a substantial genetic influence on carapace shape. Based on the relationship between this trait and genetic lineages, we propose the existence of at least three distinct morphotypes of C. mydas. Well-defined groups in some foraging grounds (Galapagos, Costa Rica and New Zealand) may suggest that ecological or environmental conditions in these sites could also be influencing carapace shape in C. mydas. Geometric morphometrics is a suitable tool to differentiate genetic lineages in this cosmopolitan marine species. Consequently, this study opens new possibilities to explore and test ecological and evolutionary hypotheses in species with wide morphological variation and broad geographic distribution range.

Prognostic value of changes in brain tissue oxygen pressure before and after decompressive craniectomy following severe traumatic brain injury.

OBJECTIVE In severe traumatic brain injury (TBI), the effects of decompressive craniectomy (DC) on brain tissue oxygen pressure (PbtO2) and outcome are unclear. The authors aimed to investigate whether changes in PbtO2 after DC could be used as an independent prognostic factor. METHODS The authors conducted a retrospective, observational study at 2 university hospital ICUs. The study included 42 patients who were admitted with isolated moderate or severe TBI and underwent intracranial pressure (ICP) and PbtO2 monitoring before and after DC. The indication for DC was an ICP higher than 25 mm Hg refractory to first-tier medical treatment. Patients who underwent primary DC for mass lesion evacuation were excluded. However, patients were included who had undergone previous surgery as long as it was not a craniectomy. ICP/PbtO2 monitoring probes were located in an apparently normal area of the most damaged hemisphere based on cranial CT scanning findings. PbtO2 values were routinely recorded hourly before and after DC, but for comparisons the authors used the first PbtO2 value on ICU admission and the number of hours with PbtO2 < 15 mm Hg before DC, as well as the mean PbtO2 every 6 hours during 24 hours pre- and post-DC. The end point of the study was the 6-month Glasgow Outcome Scale; a score of 4 or 5 was considered a favorable outcome, whereas a score of 1-3 was considered an unfavorable outcome. RESULTS Of the 42 patients included, 26 underwent unilateral DC and 16 bilateral DC. The median Glasgow Coma Scale score at the scene of the accident or at the initial hospital before the patient was transferred to one of the 2 ICUs was 7 (interquartile range [IQR] 4-14). The median time from admission to DC was 49 hours (IQR 7-301 hours). Before DC, the median ICP and PbtO2 at 6 hours were 35 mm Hg (IQR 28-51 mm Hg) and 11.4 mm Hg (IQR 3-26 mm Hg), respectively. In patients with favorable outcome, PbtO2 at ICU admission was higher and the percentage of time that pre-DC PbtO2 was < 15 mm Hg was lower (19 ± 4.5 mm Hg and 18.25% ± 21.9%, respectively; n = 28) than in those with unfavorable outcome (12.8 ± 5.2 mm Hg [p < 0.001] and 59.58% ± 38.8% [p < 0.001], respectively; n = 14). There were no significant differences in outcomes according to the mean PbtO2 values only during the last 12 hours before DC, the hours of refractory intracranial hypertension, the timing of DC from admission, or the presence/absence of previous surgery. In contrast, there were significant differences in PbtO2 values during the 12- to 24-hour period before DC. In most patients, PbtO2 increased during the 24 hours after DC but these changes were more pronounced in patients with favorable outcome than in those with unfavorable outcome (28.6 ± 8.5 mm Hg vs 17.2 ± 5.9 mm Hg, p < 0.0001; respectively). The areas under the curve for the mean PbtO2 values at 12 and 24 hours after DC were 0.878 (95% CI 0.75-1, p < 0.0001) and 0.865 (95% CI 0.73-1, p < 0.0001), respectively. CONCLUSIONS The authors' findings suggest that changes in PbtO2 before and after DC, measured with probes in healthy-appearing areas of the most damaged hemisphere, have independent prognostic value for the 6-month outcome in TBI patients.