Admission Features Associated With Paroxysmal Sympathetic Hyperactivity After Traumatic Brain Injury: A Case-Control Study

Traumatic Brain Injury and Traumatic Spinal Cord Injury

OBJECTIVE

This article reviews the mechanisms of primary traumatic injury to the brain and spinal cord, with an emphasis on grading severity, identifying surgical indications, anticipating complications, and managing secondary injury.

LATEST DEVELOPMENTS

Serum biomarkers have emerged for clinical decision making and prognosis after traumatic injury. Cortical spreading depolarization has been identified as a potentially modifiable mechanism of secondary injury after traumatic brain injury. Innovative methods to detect covert consciousness may inform prognosis and enrich future studies of coma recovery. The time-sensitive nature of spinal decompression is being elucidated.

ESSENTIAL POINTS

Proven management strategies for patients with severe neurotrauma in the intensive care unit include surgical decompression when appropriate, the optimization of perfusion, and the anticipation and treatment of complications. Despite validated models, predicting outcomes after traumatic brain injury remains challenging, requiring prognostic humility and a model of shared decision making with surrogate decision makers to establish care goals. Penetrating injuries, especially gunshot wounds, are often devastating and require public health and policy approaches that target prevention.

Overlapping Physiologic Signs of Sepsis and Paroxysmal Sympathetic Hyperactivity After Traumatic Brain Injury: Exploring A Clinical Conundrum

BACKGROUND

Paroxysmal sympathetic hyperactivity (PSH) occurs in a subset of patients with traumatic brain injury (TBI) and is associated with worse outcomes. Sepsis is also associated with worse outcomes after TBI and shares several physiologic features with PSH, potentially creating diagnostic confusion and suboptimal management of each. This is the first study to directly investigate the interaction between PSH and infection using robust diagnostic criteria.

METHODS

We performed a retrospective cohort study of patients with TBI admitted to a level I trauma center intensive care unit with hospital length of stay of at least 2 weeks. From January 2016 to July 2018, 77 patients diagnosed with PSH were 1:1 matched by age and Glasgow Coma Scale to 77 patients without PSH. Trauma infectious diseases subspecialists prospectively documented assessments corroborating diagnoses of infection. Extracted data including incidence, timing, classification, and anatomical source of infections were compared according to PSH diagnosis. We also evaluated daily PSH clinical feature severity scores and systemic inflammatory response syndrome (SIRS) criteria and compared values for patients with and without confirmed infection, stratified by PSH diagnosis.

RESULTS

During the first 2 weeks of hospitalization, there were no differences in rates of suspected (62%) nor confirmed (48%) infection between patients with PSH and controls. Specific treatments for PSH were initiated on median hospital day 7 and for confirmed infections on median hospital day 8. SIRS criteria could identify infection only in patients who were not diagnosed with PSH.

CONCLUSIONS

In the presence of brain injury-induced autonomic nervous system dysregulation, the initiation and continuation of antimicrobial therapy is a challenging clinical decision, as standard physiologic markers of sepsis do not distinguish infected from noninfected patients with PSH, and these entities often present around the same time. Clinicians should be aware that PSH is a potential driver of SIRS, and familiarity with its diagnostic criteria as proposed by the PSH assessment measure is important. Management by a multidisciplinary team attentive to these issues may reduce rates of inappropriate antibiotic usage and misdiagnoses.

Physicians' beliefs and perceived importance of traumatic brain injury-associated agitation in critically ill patients: a survey of Canadian intensivists

PURPOSE

Agitation is a common behavioural problem following traumatic brain injury (TBI). Intensive care unit (ICU) physicians' perspectives regarding TBI-associated agitation are unknown. Our objective was to describe physicians' beliefs and perceived importance of TBI-associated agitation in critically ill patients.

METHODS

Following current standard guidance, we built an electronic, self-administrated, 42-item survey, pretested it for reliability and validity, and distributed it to 219 physicians working in 18 ICU level-1 trauma centres in Canada. We report the results using descriptive statistics.

RESULTS

The overall response rate was 93/219 (42%), and 76/93 (82%) respondents completed the full survey. Most respondents were men with ten or more years of experience. Respondents believed that pre-existing dementia (90%) and regular recreational drug use (86%) are risk factors for agitation. Concerning management, 91% believed that the use of physical restraints could worsen agitation, 90% believed that having family at the bedside reduces agitation, and 72% believed that alpha-2 adrenergic agonists are efficacious for managing TBI agitation. Variability was observed in beliefs on epidemiology, sex, gender, age, socioeconomic status, and other pharmacologic options. Respondents considered TBI agitation frequent enough to justify the implementation of management protocols (87%), perceived the current level of clinical evidence on TBI agitation management to be insufficient (84%), and expressed concerns about acute and long-term detrimental outcomes and burden to patients, health care professionals, and relatives (85%).

CONCLUSION

Traumatic brain injury-associated agitation in critically ill patients was perceived as an important issue for most ICU physicians. Physicians agreed on multiple approaches to manage TBI-associated agitation although agreement on epidemiology and risk factors was variable.

Paroxysmal Sympathetic Hyperactivity in Stroke

OBJECTIVE

Paroxysmal sympathetic hyperactivity (PSH) is a life-threatening neurological emergency associated with severe brain injury. Stroke-related PSH, particularly post-aneurysmal subarachnoid hemorrhage (aSAH) PSH, has been relatively understudied and is often misdiagnosed as an aSAH-related hyperadrenergic crisis. This study aims to clarify the feature of stroke-related PSH.

METHODS

This study discusses the case of a patient with post-aSAH PSH and identifies 19 articles (25 cases) on stroke-related PSH by searching the PubMed database from 1980 to 2021.

RESULTS

In the total cohort, 15 (60.0%) patients were male and the average age was 40.1 ± 16.6 years. The primary diagnoses included intracranial hemorrhage (13 cases, 52.0%), cerebral infarction (7 cases, 28.0%), subarachnoid hemorrhage (4 cases, 16.0%), and intraventricular hemorrhage (1 case, 4.0%). The sites of stroke damage were predominantly the cerebral lobe (10 cases, 40.0%), basal ganglia (8 cases, 32.0%), and the pons (4 cases, 16.0%). The median time of PSH onset after admission was 5 (1-180) days. Most cases employed combination therapy with sedation drugs, beta-blockers, gabapentin, and clonidine. On the Glasgow Outcome Scale, outcomes included death (4 cases, 21.1%), vegetative state (2 cases, 10.5%), severe disability (7 cases, 36.8%), and in only one case (5.3%) was a good recovery noted.

CONCLUSIONS

The clinical features and treatment of post-aSAH PSH differed from those of aSAH-related hyperadrenergic crises. Early diagnosis and treatment can prevent severe complications. PSH should be acknowledged as a potential complication of aSAH. Differential diagnosis can aid in developing individualized treatment plans and improving patient prognosis.

How to predict the outcome of primary brainstem hemorrhage: Six-year results of a single-center retrospective analysis

Primary brainstem hemorrhage (PBH) is one of the most fatal intracranial hemorrhages, evaluating the prognosis in the early stage is vital for appropriate therapeutic planning. Our study aimed to identify risk factors for 30-day mortality and 90-day functional recovery of PBH. Data from 63 patients with PBH admitted to Beijing Chaoyang Hospital between 2016 and 2022 were retrieved for this study. We grouped the patients according to 30-day survival or 90-day functional recovery. Independent risk factors of 30-day mortality and 90-day functional recovery were identified by univariate and multivariate logistic regression analyses. 31 patients (49.2%) died within 30 days and 22 patients (34.9%) achieved better functional recovery. By multivariate analysis, Glasgow coma scale <9 on admission and tachycardia were significantly associated with 30-day mortality, while the hematoma volume >5 mL was an independent risk factor for 90-day functional recovery. Initial level of consciousness, tachycardia, massive hematoma were risk factors for prognosis, which must be seriously evaluated for therapeutic planning.

Neurotrauma

PURPOSE OF REVIEW

This review will highlight the latest research relevant to the clinical care of traumatic brain injury (TBI) patients over the last 2 years while underscoring the implications of these advances in the understanding of diagnosis, treatment, and prognosis of TBI.

RECENT FINDINGS

Brain tissue oxygenation monitoring can identify hypoperfusion as an adjunct to intracerebral pressure monitoring. Multiple biomarker assays are now available to help clinicians screen for mild TBI and biomarker elevations correlate with the size of intracranial injury. Beta-blocker exposure following TBI has demonstrated a survival benefit in those with TBI though the mechanism for this remains unknown. The optimal timing for venous thromboembolism prophylaxis for TBI patients is still uncertain.

SUMMARY

The current characterization of TBI as mild, moderate, or severe fails to capture the complexity of the disease process and helps little with prognostication. Molecular biomarkers and invasive monitoring devices including brain tissue oxygenation and measures of cerebral autoregulation are being utilized more commonly and can help guide therapy. Extracranial complications following TBI are common and include infection, respiratory failure, coagulopathy, hypercoagulability, and paroxysmal sympathetic hyperactivity.

Paroxysmal Sympathetic Hyperactivity in Adult Patients with Brain Injury: A Systematic Review and Meta-Analysis

BACKGROUND

Paroxysmal sympathetic hyperactivity (PSH) is a syndrome of excessive sympathetic activity, mainly occurring in severe traumatic brain injury. However, few studies have reported the frequency of PSH and its related risk factors in adult patients with brain injury.

METHODS

We performed this systematic review and meta-analysis to estimate the combined incidence of PSH and the associated risk factors in adult patients with brain injury. This study was registered with the PROSPERO international prospective register of systematic reviews (https://www.crd.york. ac.uk/PROSPERO/Identifier: CRD 42021260493), and a systematic search was conducted of the scientific databases Embase, PubMed, Web of Science, Cochrane Library, and Google Scholar. All identified observational studies regarding the incidence and risk factors of PSH in adult patients with brain injury were included. Two authors extracted data independently; data were analyzed by STATA version 16.

RESULTS

The search yielded 9 studies involving 1643 adult patients. PSH was detected in 438 patients. The combined incidence of PSH in adult patients with brain injury was 27.4% (95% confidence interval [CI], 0.190-0.358). The risk factors include patients' age (SMD = -0.592; I² = 77.5%; 95% CI, -1.027 to -0.156; P = 0.008), traffic accident (odds ratio [OR], 1.783; I² =18.0%; 95% CI, 1.128-2.820; P = 0.013), admission Glasgow Coma Scale score (SMD = -1.097; I² =28.3%; 95% CI, -1.500 to -0.693; P = 0.000), hydrocephalus (OR, 3.936; I² =67.9%; 95% CI, 1.144-13.540; P = 0.030), and diffuse axonal injury (OR, 4.747; I² =71.1%; 95% CI, 1.221-18.463; P = 0.025) and were significantly associated with the presence of PSH after brain injury.

CONCLUSIONS

PSH occurs in nearly a quarter of adult patients with brain injury. Patient's age, traffic accident, admission Glasgow Coma Scale score, hydrocephalus, and diffuse axonal injury were risk factors for PSH in adult patients with brain injury. These findings may contribute to novel strategies for early diagnosis and interventions that aid in the rehabilitation of patients with brain injury.

Initial neurocritical care of severe traumatic brain injury: New paradigms and old challenges

Background:

Early neurocritical care aims to ameliorate secondary traumatic brain injury (TBI) and improve neural salvage. Increased engagement of neurosurgeons in neurocritical care is warranted as daily briefings between the intensivist and the neurosurgeon are considered a quality indicator for TBI care. Hence, neurosurgeons should be aware of the latest evidence in the neurocritical care of severe TBI (sTBI).

Methods:

We conducted a narrative literature review of bibliographic databases (PubMed and Scopus) to examine recent research of sTBI.

Results:

This review has several take-away messages. The concept of critical neuroworsening and its possible causes is discussed. Static thresholds of intracranial pressure (ICP) and cerebral perfusion pressure may not be optimal for all patients. The use of dynamic cerebrovascular reactivity indices such as the pressure reactivity index can facilitate individualized treatment decisions. The use of ICP monitoring to tailor treatment of intracranial hypertension (IHT) is not routinely feasible. Different guidelines have been formulated for different scenarios. Accordingly, we propose an integrated algorithm for ICP management in sTBI patients in different resource settings. Although hyperosmolar therapy and decompressive craniectomy are standard treatments for IHT, there is a lack high-quality evidence on how to use them. A discussion of the advantages and disadvantages of invasive ICP monitoring is included in the study. Addition of beta-blocker, anti-seizure, and anticoagulant medications to standardized management protocols (SMPs) should be considered with careful patient selection.

Conclusion:

Despite consolidated research efforts in the refinement of SMPs, there are still many unanswered questions and novel research opportunities for sTBI care.

Leveraging Continuous Vital Sign Measurements for Real-Time Assessment of Autonomic Nervous System Dysfunction After Brain Injury: A Narrative Review of Current and Future Applications

Subtle and profound changes in autonomic nervous system (ANS) function affecting sympathetic and parasympathetic homeostasis occur as a result of critical illness. Changes in ANS function are particularly salient in neurocritical illness, when direct structural and functional perturbations to autonomic network pathways occur and may herald impending clinical deterioration or intervenable evolving mechanisms of secondary injury. Sympathetic and parasympathetic balance can be measured quantitatively at the bedside using multiple methods, most readily by extracting data from electrocardiographic or photoplethysmography waveforms. Work from our group and others has demonstrated that data-analytic techniques can identify quantitative physiologic changes that precede clinical detection of meaningful events, and therefore may provide an important window for time-sensitive therapies. Here, we review data-analytic approaches to measuring ANS dysfunction from routine bedside physiologic data streams and integrating this data into multimodal machine learning-based model development to better understand phenotypical expression of pathophysiologic mechanisms and perhaps even serve as early detection signals. Attention will be given to examples from our work in acute traumatic brain injury on detection and monitoring of paroxysmal sympathetic hyperactivity and prediction of neurologic deterioration, and in large hemispheric infarction on prediction of malignant cerebral edema. We also discuss future clinical applications and data-analytic challenges and future directions.