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.

Plasma Levels, Temporal Trends and Clinical Associations between Biomarkers of Inflammation and Vascular Homeostasis after Pediatric Traumatic Brain Injury.

Expression of inflammatory (interleukin-6 [IL-6]) and vascular homeostatic (angiopoietin-2 [AP-2], endothelin-1 [ET-1], endocan-2 [EC-2]) biomarkers in pediatric traumatic brain injury (TBI) was examined in this prospective, observational cohort study of 28 children hospitalized with mild, moderate, and severe TBI by clinical measures (age, sex, Glasgow Coma Scale score [GCS], Injury Severity Score [ISS], and cerebral autoregulation status). Biomarker patterns suggest an inverse relationship between GCS and AP-2, GCS and IL-6, ISS and ET-1, but a direct relationship between GCS and ET-1 and ISS and AP-2. Biomarker patterns suggest an inverse relationship between AP-2 and ET-1, AP-2 and EC-2, but a direct relationship between AP-2 and IL-6, IL-6 and EC-2, and IL-6 and ET-1. Plasma concentrations of inflammatory and vascular homeostatic biomarkers suggest a role for inflammation and disruption of vascular homeostasis during the first 10 days across the severity spectrum of pediatric TBI. Although not statistically significant, without impact on cerebral autoregulation, biomarker patterns suggest a relationship between inflammation and alterations in vascular homeostasis. The large variation in biomarker levels within TBI severity and age groups, and by sex suggests other contributory factors to biomarker expression.

Prevalence, Evolution, and Extent of Impaired Cerebral Autoregulation in Children Hospitalized With Complex Mild Traumatic Brain Injury.

OBJECTIVES: To examine cerebral autoregulation in children with complex mild traumatic brain injury. DESIGN: Prospective observational convenience sample. SETTING: PICU at a level I trauma center. PATIENTS: Children with complex mild traumatic brain injury (trauma, admission Glasgow Coma Scale score 13-15 with either abnormal head CT, or history of loss of consciousness). INTERVENTIONS: Cerebral autoregulation was tested using transcranial Doppler ultrasound between admission day 1 and 8. MEASUREMENTS AND MAIN RESULTS: The primary outcome was prevalence of impaired cerebral autoregulation (autoregulation index < 0.4),determined using transcranial Doppler ultrasonography and tilt testing. Secondary outcomes examined factors associated with and evolution and extent of impairment. Cerebral autoregulation testing occurred in 31 children 10 years (SD, 5.2 yr), mostly male (59%) with isolated traumatic brain injury (91%), median admission Glasgow Coma Scale 15, Injury Severity Scores 14.2 (SD, 7.7), traumatic brain injury due to fall (50%), preadmission loss of consciousness (48%), and abnormal head CT scan (97%). Thirty-one children underwent 56 autoregulation tests. Impaired cerebral autoregulation occurred in 15 children (48.4%) who underwent 19 tests; 68% and 32% of tests demonstrated unilateral and bilateral impairment, respectively. Compared with children on median day 6 of admission after traumatic brain injury, impaired autoregulation was most common in the first 5 days after traumatic brain injury (day 1: relative risk, 3.7; 95% CI, 1.9-7.3 vs day 2: relative risk, 2.7; 95% CI, 1.1-6.5 vs day 5: relative risk, 1.33; 95% CI, 0.7-2.3). Children with impaired autoregulation were older (12.3 yr [SD, 1.3 yr] vs 8.7 yr [SD, 1.1 yr]; p = 0.04) and tended to have subdural hematoma (64% vs 44%), epidural hematoma (29% vs 17%), and subarachnoid hemorrhage (36% vs 28%). Eight children (53%) were discharged home with ongoing impaired cerebral autoregulation. CONCLUSIONS: Impaired cerebral autoregulation is common in children with complex mild traumatic brain injury, despite reassuring admission Glasgow Coma Scale 13-15. Children with complex mild traumatic brain injury have abnormal cerebrovascular hemodynamics, mostly during the first 5 days. Impairment commonly extends to the contralateral hemisphere and discharge of children with ongoing impaired cerebral autoregulation is common.

Primary External Ventricular Drainage Catheter Versus Intraparenchymal ICP Monitoring: Outcome Analysis.

BACKGROUND: Intracranial pressure (ICP) monitoring is central to the care of severe traumatic brain injury (TBI). External ventricular drains (EVD) allow ICP control via cerebrospinal fluid drainage, whereas intraparenchymal monitors (IPM) for ICP do not, but it is unclear whether EVD placement improves outcomes. To evaluate whether there exists a difference in patient outcomes with the use of EVD versus IPM in severe TBI patients, we conducted a retrospective cohort study using data from the Citicoline Brain Injury Treatment trial. METHODS: Adults with Glasgow Coma Score < 9 who had either an EVD or IPM placed within 6 h of study center arrival were included. We compared patients with EVD placement to those without on Glasgow Outcome Scale-Extended (GOS-E) and neuropsychological performance at 180 days, mortality, and intensive care unit length of stay. We used regression models with propensity score weighting for probability of EVD placement to test for association between EVD use and outcomes. Of 224 patients included, 45% received an EVD. RESULTS: EVD patients had lower GOS-E at 180 days [3.8 ± 2.2 vs 4.9 ± 2.2, p = 0.002; weighted difference - 0.97, 95% CI (- 1.58, - 0.37)], higher in-hospital mortality [23% vs 10%, p = 0.014; weighted OR 2.46, 95% CI (1.20, 5.05)], and did significantly worse on all 8 neuropsychological measures. Additional sensitivity analysis was performed to minimize confounding effects supported our initial results. CONCLUSIONS: Our retrospective data analysis suggests that early placement of EVDs in severe TBI is associated with worse functional and neuropsychological outcomes and higher mortality than IPMs and future prospective trials are needed to determine whether these results represent an important consideration for clinicians.

Transcranial Doppler Microemboli Monitoring for Stroke Risk Stratification in Blunt Cerebrovascular Injury.

OBJECTIVES: To assess whether microemboli burden, assessed noninvasively by bedside transcranial Doppler ultrasonography, correlates with risk of subsequent stroke greater than 24 hours after hospital arrival among patients with blunt cerebrovascular injury. The greater than 24-hour time frame provides a window for transcranial Doppler examinations and therapeutic interventions to prevent stroke. DESIGN: Retrospective cohort study. SETTING: Level I trauma center. PATIENTS: One thousand one hundred forty-six blunt cerebrovascular injury patients over 10 years. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 1,146 blunt cerebrovascular injury patients; 54 (4.7%) experienced stroke detected greater than 24 hours after arrival. Among those with isolated internal carotid artery injuries, five of nine with delayed stroke had positive transcranial Dopplers (at least one microembolus detected with transcranial Dopplers) before stroke, compared with 46 of 248 without (risk ratio, 5.05; 95% CI, 1.41-18.13). Stroke risk increased with the number of microemboli (adjusted risk ratio, 1.03/microembolus/hr; 95% CI, 1.01-1.05) and with persistently positive transcranial Dopplers over multiple days (risk ratio, 16.0; 95% CI, 2.00-127.93). Among patients who sustained an internal carotid artery injury with or without additional vessel injuries, positive transcranial Dopplers predicted stroke after adjusting for ipsilateral and contralateral internal carotid artery injury grade (adjusted risk ratio, 2.91; 95% CI, 1.42-5.97). No patients with isolated vertebral artery injuries had positive transcranial Dopplers before stroke, and positive transcranial Dopplers were not associated with delayed stroke among patients who sustained a vertebral artery injury with or without additional vessel injuries (risk ratio, 0.90; 95% CI, 0.21-3.83). CONCLUSIONS: Microemboli burden is associated with higher risk of stroke due to internal carotid artery injuries, but monitoring was not useful for vertebral artery injuries.

Brain Oxygen Optimization in Severe Traumatic Brain Injury Phase-II: A Phase II Randomized Trial.

OBJECTIVES: A relationship between reduced brain tissue oxygenation and poor outcome following severe traumatic brain injury has been reported in observational studies. We designed a Phase II trial to assess whether a neurocritical care management protocol could improve brain tissue oxygenation levels in patients with severe traumatic brain injury and the feasibility of a Phase III efficacy study. DESIGN: Randomized prospective clinical trial. SETTING: Ten ICUs in the United States. PATIENTS: One hundred nineteen severe traumatic brain injury patients. INTERVENTIONS: Patients were randomized to treatment protocol based on intracranial pressure plus brain tissue oxygenation monitoring versus intracranial pressure monitoring alone. Brain tissue oxygenation data were recorded in the intracranial pressure -only group in blinded fashion. Tiered interventions in each arm were specified and impact on intracranial pressure and brain tissue oxygenation measured. Monitors were removed if values were normal for 48 hours consecutively, or after 5 days. Outcome was measured at 6 months using the Glasgow Outcome Scale-Extended. MEASUREMENTS AND MAIN RESULTS: A management protocol based on brain tissue oxygenation and intracranial pressure monitoring reduced the proportion of time with brain tissue hypoxia after severe traumatic brain injury (0.45 in intracranial pressure-only group and 0.16 in intracranial pressure plus brain tissue oxygenation group; p < 0.0001). Intracranial pressure control was similar in both groups. Safety and feasibility of the tiered treatment protocol were confirmed. There were no procedure-related complications. Treatment of secondary injury after severe traumatic brain injury based on brain tissue oxygenation and intracranial pressure values was consistent with reduced mortality and increased proportions of patients with good recovery compared with intracranial pressure-only management; however, the study was not powered for clinical efficacy. CONCLUSIONS: Management of severe traumatic brain injury informed by multimodal intracranial pressure and brain tissue oxygenation monitoring reduced brain tissue hypoxia with a trend toward lower mortality and more favorable outcomes than intracranial pressure-only treatment. A Phase III randomized trial to assess impact on neurologic outcome of intracranial pressure plus brain tissue oxygenation-directed treatment of severe traumatic brain injury is warranted.

Natural History and Management of Blunt Traumatic Pseudoaneurysms of the Internal Carotid Artery: The Harborview Algorithm Based Off a 10-Year Experience.

OBJECTIVE: To define the natural history of, and treatment strategy for, blunt traumatic internal carotid artery (ICA) pseudoaneurysms. BACKGROUND: The natural history and management of traumatic ICA pseudoaneurysms is controversial. METHODS: We retrospectively identified all traumatic ICA pseudoaneurysms diagnosed on head/neck computed tomographic angiography at a high-volume trauma center over a 10-year period. Radiographic and clinical data were recorded, and a treatment algorithm was derived. RESULTS: Forty-three pseudoaneurysms were diagnosed in 39 patients. All patients were treated with daily aspirin unless contraindicated, and 82% underwent daily transcranial Doppler ultrasonography with embolic monitoring. A rate of 8 or more emboli per hour was predictive of embolic stroke (P = 0.0076). Acute ischemic or embolic stroke was seen in 7 patients (16%) with an overall mortality in this subpopulation of 42% (n = 3). Four patients (9%) underwent acute surgical treatment (parent vessel sacrifice and/or arterial bypass) for ongoing ischemia. Long-term radiographic and clinical follow-up was obtained for 36 surviving patients (mean = 8 months; range: 1 week-5 years), all of whom were maintained on daily aspirin. No delayed ischemic or embolic events were reported. For ICA pseudoaneurysms treated with aspirin and observation alone, 9 (28%) increased in size, 17 (53%) decreased or stabilized, and 6 (19%) resolved. Enlargement of 5 mm or more in maximal diameter underwent delayed endovascular treatment with a 100% obliteration rate and no complications. CONCLUSIONS: Traumatic ICA pseudoaneurysms are safely treated with daily aspirin, embolic monitoring, and radiographic surveillance. Acute stroke or hemorrhage, or delayed radiographic progression, are indications for endovascular or surgical treatment.

A trial of intracranial-pressure monitoring in traumatic brain injury.

BACKGROUND: Intracranial-pressure monitoring is considered the standard of care for severe traumatic brain injury and is used frequently, but the efficacy of treatment based on monitoring in improving the outcome has not been rigorously assessed. METHODS: We conducted a multicenter, controlled trial in which 324 patients 13 years of age or older who had severe traumatic brain injury and were being treated in intensive care units (ICUs) in Bolivia or Ecuador were randomly assigned to one of two specific protocols: guidelines-based management in which a protocol for monitoring intraparenchymal intracranial pressure was used (pressure-monitoring group) or a protocol in which treatment was based on imaging and clinical examination (imaging-clinical examination group). The primary outcome was a composite of survival time, impaired consciousness, and functional status at 3 months and 6 months and neuropsychological status at 6 months; neuropsychological status was assessed by an examiner who was unaware of protocol assignment. This composite measure was based on performance across 21 measures of functional and cognitive status and calculated as a percentile (with 0 indicating the worst performance, and 100 the best performance). RESULTS: There was no significant between-group difference in the primary outcome, a composite measure based on percentile performance across 21 measures of functional and cognitive status (score, 56 in the pressure-monitoring group vs. 53 in the imaging-clinical examination group; P=0.49). Six-month mortality was 39% in the pressure-monitoring group and 41% in the imaging-clinical examination group (P=0.60). The median length of stay in the ICU was similar in the two groups (12 days in the pressure-monitoring group and 9 days in the imaging-clinical examination group; P=0.25), although the number of days of brain-specific treatments (e.g., administration of hyperosmolar fluids and the use of hyperventilation) in the ICU was higher in the imaging-clinical examination group than in the pressure-monitoring group (4.8 vs. 3.4, P=0.002). The distribution of serious adverse events was similar in the two groups. CONCLUSIONS: For patients with severe traumatic brain injury, care focused on maintaining monitored intracranial pressure at 20 mm Hg or less was not shown to be superior to care based on imaging and clinical examination. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01068522.).

Clinical applications of intracranial pressure monitoring in traumatic brain injury : report of the Milan consensus conference.

BACKGROUND: Intracranial pressure (ICP) monitoring has been for decades a cornerstone of traumatic brain injury (TBI) management. Nevertheless, in recent years, its usefulness has been questioned in several reports. A group of neurosurgeons and neurointensivists met to openly discuss, and provide consensus on, practical applications of ICP in severe adult TBI. METHODS: A consensus conference was held in Milan on October 5, 2013, putting together neurosurgeons and intensivists with recognized expertise in treatment of TBI. Four topics have been selected and addressed in pro-con presentations: 1) ICP indications in diffuse brain injury, 2) cerebral contusions, 3) secondary decompressive craniectomy (DC), and 4) after evacuation of intracranial traumatic hematomas. The participants were asked to elaborate on the existing published evidence (without a systematic review) and their personal clinical experience. Based on the presentations and discussions of the conference, some drafts were circulated among the attendants. After remarks and further contributions were collected, a final document was approved by the participants. The group made the following recommendations: 1) in comatose TBI patients, in case of normal computed tomography (CT) scan, there is no indication for ICP monitoring; 2) ICP monitoring is indicated in comatose TBI patients with cerebral contusions in whom the interruption of sedation to check neurological status is dangerous and when the clinical examination is not completely reliable. The probe should be positioned on the side of the larger contusion; 3) ICP monitoring is generally recommended following a secondary DC in order to assess the effectiveness of DC in terms of ICP control and guide further therapy; 4) ICP monitoring after evacuation of an acute supratentorial intracranial hematoma should be considered for salvageable patients at increased risk of intracranial hypertension with particular perioperative features.

Incidence and Risk Model of Post-Traumatic Hydrocephalus in Patients with Traumatic Brain Injury.

OBJECTIVE: Post-traumatic hydrocephalus (PTH) is a complication following traumatic brain injury (TBI). Early diagnosis and treatment are essential to improving outcomes. We report the incidence and risk factors of PTH in a large TBI population while considering death as a competing risk. METHODS: We conducted a retrospective cohort study on consecutive TBI patients with radiographic intracranial abnormalities admitted to our academic medical center from 2009 to 2015. We assessed patient demographics, perioperative data, and in-hospital data as risk factors for PTH using survival analysis with death as a competing risk. RESULTS: Among 7,473 patients, the overall incidence of PTH requiring shunt surgery was 0.94%. The adjusted cumulative incidence was 0.99%. The all-cause cumulative hazard for death was 32.6%, which was considered a competing risk during analysis. Craniectomy (HR 11.53, P < 0.001, 95% CI 5.57-223.85), venous sinus injury (HR 4.13, P = 0.01, 95% CI 1.53-11.16), and age ≤5 (P < 0.001) were significant risk factors for PTH. Glasgow Coma Score (GCS) > 13 was protective against shunt placement (HR 0.50, P = 0.04, 95% CI 0.26-0.97). Shunt surgery occurred after hospital discharge in 60% of patients. CONCLUSIONS: We describe the incidence and risk factors for PTH in a large traumatic brain injury (TBI) population. Most cases of PTH were diagnosed after hospital discharge, suggesting that close follow-up and multidisciplinary diagnostic vigilance for PTH are needed to prevent morbidity and disability.

Extracranial Complications in Monitored and Nonmonitored Patients with Traumatic Brain Injury in the BEST TRIP Trial and a Companion Observational Cohort.

INTRODUCTION: Extracranial complications occur commonly in patients with traumatic brain injury (TBI) and can have implications for patient outcome. Patient-specific risk factors for developing these complications are not well studied, particularly in low and middle-income countries (LMIC). The study objective was to determine patient-specific risk factors for development of extracranial complications in TBI. METHODS: We assessed the relationship between patient demographic and injury factors and incidence of extracranial complications using data collected September 2008-October 2011 from the BEST TRIP trial, a randomized controlled trial assessing TBI management protocolized on intracranial pressure (ICP) monitoring versus imaging and clinical exam, and a companion observational patient cohort. RESULTS: Extracranial infections (55%), respiratory complications (19%), hyponatremia (27%), hypernatremia (27%), hospital acquired pressure ulcers (6%), coagulopathy (9%), cardiac arrest (10%), and shock (5%) occurred at a rate of ≥5% in our study population; overall combined rate of these complications was 82.3%. Tracheostomy in the intensive care unit (P < 0.001), tracheostomy timing (P = 0.025), mannitol and hypertonic saline doses (P < 0.001), brain-specific therapy days and brain-specific therapy intensity (P < 0.001), extracranial surgery (P < 0.001), and neuroworsening with pupil asymmetry (P = 0.038) were all significantly related to the development of one of these complications by univariable analysis. Multivariable analysis revealed ICP monitor use and brain-specific therapy intensity to be the most common factors associated with individual complications. CONCLUSIONS: Extracranial complications are common following TBI. ICP monitoring and treatment are related to extra-cranial complications. This supports the need for reassessing the risk-benefit balance of our current management approaches in the interest of improving outcome.

A comparison of computed tomography angiography and digital subtraction angiography for the diagnosis of penetrating cerebrovascular injury: a prospective multicenter study.

OBJECTIVE: In this research, the authors sought to characterize the incidence and extent of cerebrovascular lesions after penetrating brain injury in a civilian population and to compare the diagnostic value of head computed tomography angiography (CTA) and digital subtraction angiography (DSA) in their diagnosis. METHODS: This was a prospective multicenter cohort study of patients with penetrating brain injury due to any mechanism presenting at two academic medical centers over a 3-year period (May 2020 to May 2023). All patients underwent both CTA and DSA. The sensitivity and specificity of CTA was calculated, with DSA considered the gold standard. The number of DSA studies needed to identify a lesion requiring treatment that had not been identified on CTA was also calculated. RESULTS: A total of 73 patients were included in the study, 33 of whom had at least 1 penetrating cerebrovascular injury, for an incidence of 45.2%. The injuries included 13 pseudoaneurysms, 11 major arterial occlusions, 9 dural venous sinus occlusions, 8 dural arteriovenous fistulas, and 6 carotid cavernous fistulas. The sensitivity of CTA was 36.4%, and the specificity was 85.0%. Overall, 5.6 DSA studies were needed to identify a lesion requiring treatment that had not been identified with CTA. CONCLUSIONS: Cerebrovascular injury is common after penetrating brain injury, and CTA alone is insufficient to diagnosis these injuries. Patients with penetrating brain injuries should routinely undergo DSA.

Acute Extra-Arachnoid Subdural Hematomas in Patients 50 Years and Older: When Subdurals Act Like Epidurals.

BACKGROUND: Some patients with subdural hematoma (SDH) with acute extra-arachnoid lesions and without concomitant subarachnoid blood or contusions may present in similarly grave neurological condition compared with the general population of patients with SDH. However, these patients often make an impressive neurological recovery. This study compared neurological outcomes in patients with extra-arachnoid SDH with all other SDH patients. METHODS: We compared a prospective series of extra-arachnoid SDH patients without subarachnoid hemorrhage or other concomitant intracranial injury with a Transforming Research and Clinical Knowledge in TBI control group with SDH only. We performed inverse probability weighting for key characteristics and ordinal regression with and without controlling for midline shift comparing neurological outcomes (Extended Glasgow Outcome Scale score) at 2 weeks. We used the Corticosteroid Randomization After Significant Head Injury prognostic model to predict mortality based on age, Glasgow Coma Scale score, pupil reactivity, and major extracranial injury. RESULTS: Mean midline shift was significantly different between extra-arachnoid SDH and control groups (7.2 mm vs. 2.7 mm, P < 0.001). After weighting for group allocation and controlling for midline shift, extra-arachnoid SDH patients had 5.68 greater odds (P < 0.001) of a better 2-week Extended Glasgow Outcome Scale score than control patients. Mortality in the extra-arachnoid SDH group was less than predicted by the Corticosteroid Randomization After Significant Head Injury prognostic model (10% vs. 21% predicted). CONCLUSIONS: Patients with extra-arachnoid SDH have significantly better 2-week neurological outcomes and lower mortality than predicted by the Corticosteroid Randomization After Significant Head Injury model. Neurosurgeons should consider surgery for this patient subset even in cases of poor neurological examination, older age, and large hematoma with high degree of midline shift.

The Neurological Pupil index for outcome prognostication in people with acute brain injury (ORANGE): a prospective, observational, multicentre cohort study.

BACKGROUND: Improving the prognostication of acute brain injury is a key element of critical care. Standard assessment includes pupillary light reactivity testing with a hand-held light source, but findings are interpreted subjectively; automated pupillometry might be more precise and reproducible. We aimed to assess the association of the Neurological Pupil index (NPi)-a quantitative measure of pupillary reactivity computed by automated pupillometry-with outcomes of patients with severe non-anoxic acute brain injury. METHODS: ORANGE is a multicentre, prospective, observational cohort study at 13 hospitals in eight countries in Europe and North America. Patients admitted to the intensive care unit after traumatic brain injury, aneurysmal subarachnoid haemorrhage, or intracerebral haemorrhage were eligible for the study. Patients underwent automated infrared pupillometry assessment every 4 h during the first 7 days after admission to compute NPi, with values ranging from 0 to 5 (with abnormal NPi being <3). The co-primary outcomes of the study were neurological outcome (assessed with the extended Glasgow Outcome Scale [GOSE]) and mortality at 6 months. We used logistic regression to model the association between NPi and poor neurological outcome (GOSE ≤4) at 6 months and Cox regression to model the relation of NPi with 6-month mortality. This study is registered with ClinicalTrials.gov, NCT04490005. FINDINGS: Between Nov 1, 2020, and May 3, 2022, 514 patients (224 with traumatic brain injury, 139 with aneurysmal subarachnoid haemorrhage, and 151 with intracerebral haemorrhage) were enrolled. The median age of patients was 61 years (IQR 46-71), and the median Glasgow Coma Scale score on admission was 8 (5-11). 40 071 NPi measurements were taken (median 40 per patient [20-50]). The 6-month outcome was assessed in 497 (97%) patients, of whom 160 (32%) patients died, and 241 (47%) patients had at least one recording of abnormal NPi, which was associated with poor neurological outcome (for each 10% increase in the frequency of abnormal NPi, adjusted odds ratio 1·42 [95% CI 1·27-1·64]; p<0·0001) and in-hospital mortality (adjusted hazard ratio 5·58 [95% CI 3·92-7·95]; p<0·0001). INTERPRETATION: NPi has clinically and statistically significant prognostic value for neurological outcome and mortality after acute brain injury. Simple, automatic, repeat automated pupillometry assessment could improve the continuous monitoring of disease progression and the dynamics of outcome prediction at the bedside. FUNDING: NeurOptics.