Paroxysmal sympathetic hyperactivity during traumatic brain injury

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

JOURNAL/nrgr/04.03/01300535-202508000-00002/figure1/v/2024-09-30T120553Z/r/image-tiff Traumatic brain injury is a prevalent disorder of the central nervous system. In addition to primary brain parenchymal damage, the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury; however, the underlying pathogenesis remains unclear, and effective intervention methods are lacking. Intestinal dysfunction is a significant consequence of traumatic brain injury. Being the most densely innervated peripheral tissue in the body, the gut possesses multiple pathways for the establishment of a bidirectional "brain-gut axis" with the central nervous system. The gut harbors a vast microbial community, and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal, hormonal, and immune pathways. A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated complications. We comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury, with a specific focus on the complex biological processes of peripheral nerves, immunity, and microbes triggered by traumatic brain injury, encompassing autonomic dysfunction, neuroendocrine disturbances, peripheral immunosuppression, increased intestinal barrier permeability, compromised responses of sensory nerves to microorganisms, and potential effector nuclei in the central nervous system influenced by gut microbiota. Additionally, we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain injury. This review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effects of the "brain-gut-microbiota axis."

Management of Medical Complications during the Rehabilitation of Moderate-Severe Traumatic Brain Injury

According to the Centers for Disease Control, in 2019, there were approximately 223,135 hospitalizations in the United States related to traumatic brain injury (TBI). If not managed properly, these patients can suffer complications with significant negative implications with respect to morbidity, mortality, and long-term functional prognosis. It is imperative that medical providers who care for patients with TBI across the entire spectrum of care readily diagnose and treat the sequela associated with moderate-severe brain trauma. This article will focus on some of the key medical issues that providers may encounter during acute inpatient rehabilitation.

Establishment and validation of a bad outcomes prediction model based on EEG and clinical parameters in prolonged disorder of consciousness

Objective

This study aimed to explore the electroencephalogram (EEG) indicators and clinical factors that may lead to poor prognosis in patients with prolonged disorder of consciousness (pDOC), and establish and verify a clinical predictive model based on these factors.

Methods

This study included 134 patients suffering from prolonged disorder of consciousness enrolled in our department of neurosurgery. We collected the data of sex, age, etiology, coma recovery scales (CRS-R) score, complications, blood routine, liver function, coagulation and other laboratory tests, resting EEG data and follow-up after discharge. These patients were divided into two groups: training set (n = 107) and verification set (n = 27). These patients were divided into a training set of 107 and a validation set of 27 for this study. Univariate and multivariate regression analysis were used to determine the factors affecting the poor prognosis of pDOC and to establish nomogram model. We use the receiver operating characteristic (ROC) and calibration curves to quantitatively test the effectiveness of the training set and the verification set. In order to further verify the clinical practical value of the model, we use decision curve analysis (DCA) to evaluate the model.

Result

The results from univariate and multivariate logistic regression analyses suggested that an increased frequency of occurrence microstate A, reduced CRS-R scores at the time of admission, the presence of episodes associated with paroxysmal sympathetic hyperactivity (PSH), and decreased fibrinogen levels all function as independent prognostic factors. These factors were used to construct the nomogram. The training and verification sets had areas under the curve of 0.854 and 0.920, respectively. Calibration curves and DCA demonstrated good model performance and significant clinical benefits in both sets.

Conclusion

This study is based on the use of clinically available and low-cost clinical indicators combined with EEG to construct a highly applicable and accurate model for predicting the adverse prognosis of patients with prolonged disorder of consciousness. It provides an objective and reliable tool for clinicians to evaluate the prognosis of prolonged disorder of consciousness, and helps clinicians to provide personalized clinical care and decision-making for patients with prolonged disorder of consciousness and their families.

The Role of Dexmedetomidine in Paroxysmal Sympathetic Hyperactivity: A Systematic Review

OBJECTIVE

The objective was to evaluate the efficacy and safety of dexmedetomidine in the treatment and prophylaxis of paroxysmal sympathetic hyperactivity (PSH).

DATA SOURCES

A review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria and queried Embase, MEDLINE (PubMed), Cochrane CENTRAL, Web of Science, SciELO, Korean Journal Index (Clarivate), Global Index Medicus, and CINAHL Plus for results through June 2023.

STUDY SELECTION AND DATA EXTRACTION

Studies providing efficacy or safety data associated with dexmedetomidine with a reported diagnosis of PSH were included. Exclusion of studies in pediatric populations, without quantitative and qualitative outcome data, and not readily translatable to English was adhered to.

DATA SYNTHESIS

Thirteen observational studies of 178 patients were included in the qualitative analysis. Reductions in PSH frequency or symptom severity were reported in 44 of 48 patients who received dexmedetomidine for acute treatment. Prophylactic use of dexmedetomidine was associated with reductions in PSH-Assessment Measure (PSH-AM) scores in postsurgical patients with traumatic brain injuries (TBIs). Adverse events associated with dexmedetomidine were either absent or reported as none.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review supports the safe and effective use of dexmedetomidine in the treatment and prophylaxis of PSH. Further investigation is required to determine optimal dosing strategies and the extent to which PSH etiology correlated to the efficacy of dexmedetomidine.

CONCLUSIONS

The use of dexmedetomidine appears to be both efficacious and safe for the treatment and prevention of PSH in patients experiencing a TBI. Additional research is needed to elucidate dosing strategies, titration parameters, and duration of therapy.

Evaluation and Pharmacologic Management of Paroxysmal Sympathetic Hyperactivity in Traumatic Brain Injury

OBJECTIVE

Paroxysmal sympathetic hyperactivity (PSH) can occur in up to 10% of severe traumatic brain injury (TBI) patients and is associated with poorer outcomes. A consensus regarding management is lacking. We provide a practical guide on the multi-faceted clinical management of PSH, including pharmacological, procedural and non-pharmacological interventions. In addition to utilizing a standardized assessment tool, the use of medications to manage sympathetic and musculoskeletal manifestations (including pain) is highlighted. Recent studies investigating new approaches to clinical management are included in this review of pharmacologic treatment options.

CONCLUSION

While studies regarding pharmacologic selection for PSH are limited, this paper suggests a clinical approach to interventions based on predominant symptom presentation (sympathetic hyperactivity, pain and/or muscle hypertonicity) and relevant medication side effects.

Paroxysmal sympathetic hyperexcitability after brain injury: A clinical analysis of case series

BACKGROUND

Paroxysmal sympathetic hyperexcitability (PSH) is a group of complex syndromes with various etiologies. Previous studies were limited to the description of traumatic brain injury (TBI), and the description of PSH after other types of brain injury was rare. We explored the clinical features, treatment, and prognosis of PSH after various types of brain injuries.

METHODS

Patients admitted to the neurosurgery intensive care unit with PSH after brain injury from July 2019 to December 2022 were included. Demographic data, clinical manifestations, drug therapy, and disease prognosis were retrospectively collected and analyzed.

RESULTS

Fifteen male and 9 female patients with PSH after brain injury were selected. TBI was most likely to cause PSH (66.7%), followed by spontaneous intracerebral hemorrhage (25%). Glasgow coma scale scores of 19 patients (79.2%) were lower than 8 and 14 patients (58.3%) underwent tracheotomy. Electroencephalogram monitoring was performed in 12 individuals, none of which showed epileptic waves. Clinical symptom scale showed mild symptoms in 17 cases (70.8%). Almost all patients were administered a combination of drugs. After follow-up, most patients had a poor prognosis and 2 (8.3%) died after discharge.

CONCLUSION

The etiology of PSH is complex. TBI may be the most common cause of PSH. Non-TBI may also be an important cause of PSH. Therefore, early identification, prevention and diagnosis are helpful for determining the prognosis and outcome of the disease.

Prediction for the prognosis of diffuse axonal injury using automated pupillometry

OBJECTIVE

Previous studies have reported various predictive indicators of diffuse axonal injury (DAI), but no consensus has not been reached. Although the efficiency of automated pupillometry in patients with consciousness disorder has been widely reported, there are few reports of its use in patients with DAI. This study aimed to investigate the significance of pupillary findings in predicting the prognosis of DAI.

PATIENTS AND METHODS

We included patients admitted to our center with a diagnosis of DAI from June 1, 2021 to June 30, 2022. Pupillary findings in both eyes were quantitatively measured by automated pupillometry every 2 hours after admission. We statistically examined the correlations between automated pupillometry parameters, the patients' characteristics, and outcomes such as the Glasgow Outcome Scale Extended (GOSE) after 6 months from injury, the time to follow command, and so on.

RESULTS

Among 22 patients included in this study, five had oculomotor nerve palsy. Oculomotor nerve palsy was correlated with all outcomes, whereas Marshall computed tomography (CT) classification, Injury severity score (ISS) and DAI grade were correlated with few outcomes. Some of the automated pupillometry parameters were significantly correlated with GOSE at 6 months after injury, and many during the first 24 hours of measurement were correlated with the time to follow command. Most of these results were not affected by adjustment using sedation period, ISS or Marshall CT classification. A subgroup analysis of patients without oculomotor nerve palsy revealed that many of the automated pupillometry parameters during the first 24 hours of measurement were significantly correlated with most of the outcomes. The cutoff values that differentiated a good prognosis (GOSE 5-8) from a poor prognosis (GOSE 1-4) were constriction velocity (CV) 1.43 (AUC = 0.81(0.62-1), p = 0.037) and maximum constriction velocity (MCV) 2.345 (AUC = 0.78 (0.58-0.98), p = 0.04). The cutoff values that differentiated the time to follow command into within 7 days and over 8 days were percentage of constriction 8 (AUC = 0.89 (0.68-1), p = 0.011), CV 0.63 (AUC = 0.92 (0.78-1), p = 0.013), MCV 0.855 (AUC = 0.9 (0.74-1), p = 0.017) and average dilation velocity 0.175 (AUC = 0.95 (0.86-1), p = 0.018).

CONCLUSIONS

The present results indicate that pupillary findings in DAI are a strong predictive indicator of the prognosis, and that quantitative measurement of them using automated pupillometry could facilitate enhanced prediction for the prognosis of DAI.

Decreased levels of hydrogen sulfide in the hypothalamic paraventricular nucleus contribute to sympathetic hyperactivity induced by cerebral infarction

Paroxysmal sympathetic hyperactivity (PSH) is a common clinical feature secondary to ischemic stroke (IS), but its mechanism is poorly understood. We aimed to investigate the role of H2S in the pathogenesis of PSH. IS patients were divided into malignant (MCI) and non-malignant cerebral infarction (NMCI) group. IS in rats was induced by the right middle cerebral artery occlusion (MCAO). H2S donor (NaHS) or inhibitor (aminooxy-acetic acid, AOAA) were microinjected into the hypothalamic paraventricular nucleus (PVN). Compared with the NMCI group, patients in the MCI group showed PSH, including tachycardia, hypertension, and more plasma norepinephrine (NE) that was positively correlated with levels of creatine kinase, glutamate transaminase, and creatinine respectively. The 1-year survival rate of patients with high plasma NE levels was lower. The hypothalamus of rats with MCAO showed increased activity, especially in the PVN region. The levels of H2S in PVN of the rats with MCAO were reduced, while the blood pressure and renal sympathetic discharge were increased, which could be ameliorated by NaHS and exacerbated by AOAA. NaHS completely reduced the disulfide bond of NMDAR1 in PC12 cells. The inhibition of NMDAR by MK-801 microinjected in PVN of rats with MCAO also could lower blood pressure and renal sympathetic discharge. In conclusion, PSH may be associated with disease progression and survival in patients with IS. Decreased levels of H2S in PVN were involved in regulating sympathetic efferent activity after cerebral infarction. Our results might provide a new strategy and target for the prevention and treatment of PSH.

Early Versus Late Tracheostomy in Patients with Traumatic Brain Injury: A US Nationwide Analysis

BACKGROUND

One of the most critical issues in patients suffering from traumatic brain injury (TBI) is protecting the airway and attempting to keep a secure airway. It is evident that tracheostomy in patients with TBI after 7-14 days can have favorable outcomes if the patient cannot be extubated; however, some clinicians have recommended early tracheostomy before 7 days.

METHODS

A retrospective cohort of inpatient study participants was queried from the National Inpatient Sample to include patients with TBI between 2016 and 2020 undergoing tracheostomy and outcomes between the two groups of early tracheostomy (ET) (< 7 days from admission) and late tracheostomy (LT) (≥ 7 days from admission) were compared.

RESULTS

We reviewed 219,005 patients with TBI, out of whom 3.04% had a tracheostomy. Patients in the ET group were younger than those in the LT group (45.02 ± 19.38 years old vs. 48.68 ± 20.50 years old, respectively, p < 0.001), mainly men (76.64% vs. 73.73%, respectively, p = 0.01), and mainly White race (59.88% vs. 57.53%, respectively, p = 0.33). The patients in the ET group had a significantly shorter length of stay as compared with those in the LT group (27.78 ± 25.96 days vs. 36.32 ± 29.30 days, respectively, p < 0.001) and had a significantly lower hospital charge ($502,502.436 ± 427,060.81 vs. $642,739.302 ± 516,078.94 per patient, respectively, p < 0.001). The whole TBI cohort mortality was reported at 7.04%, which was higher within the ET group compared with the LT group (8.69% vs. 6.07%, respectively, p < 0.001). Patients in the LT had higher odds of developing any infection (odds ratio [OR] 1.43 [1.22-1.68], p < 0.001), emerging sepsis (OR 1.61 [1.39-1.87], p < 0.001), pneumonia (OR 1.52 [1.36-1.69], p < 0.001), and respiratory failure (OR 1.30 [1.09-1.55], p = 0.004).

CONCLUSIONS

This study shows that ET can provide notable and significant benefits for patients with TBI. Future high-quality prospective studies should be performed to investigate and shed more light on the ideal timing of tracheostomy in patients with TBI.

Paroxysmal Sympathetic Hyperactivity after Traumatic Brain Injury: Current Understanding and Therapeutic Options

How to cite this article: Nasa P, Majeed NA, Juneja D. Paroxysmal Sympathetic Hyperactivity after Traumatic Brain Injury: Current Understanding and Therapeutic Options. Indian J Crit Care Med 2024;28(2):97-99.

Targeting pyroptosis with nanoparticles to alleviate neuroinflammatory for preventing secondary damage following traumatic brain injury

Posttraumatic neuroinflammation is a key driver of secondary injury after traumatic brain injury (TBI). Pyroptosis, a proinflammatory form of programmed cell death, considerably activates strong neuroinflammation and amplifies the inflammatory response by releasing inflammatory contents. Therefore, treatments targeting pyroptosis may have beneficial effects on the treatment of secondary brain damage after TBI. Here, a cysteine-alanine-glutamine-lysine peptide-modified β-lactoglobulin (β-LG) nanoparticle was constructed to deliver disulfiram (DSF), C-β-LG/DSF, to inhibit pyroptosis and decrease neuroinflammation, thereby preventing TBI-induced secondary injury. In the post-TBI mice model, C-β-LG/DSF selectively targets the injured brain, increases DSF accumulation, and extends the time of the systemic circulation of DSF. C-β-LG/DSF can alleviate brain edema and inflammatory response, inhibit secondary brain injury, promote learning, and improve memory recovery in mice after trauma. Therefore, this study likely provided a potential approach for reducing the secondary spread of TBI.

Therapy of traumatic brain injury by modern agents and traditional Chinese medicine

Traumatic brain injury (TBI) is the leading cause of disability and death, and the social burden of mortality and morbidity caused by TBI is significant. Under the influence of comprehensive factors, such as social environment, lifestyle, and employment type, the incidence of TBI continues to increase annually. Current pharmacotherapy of TBI mainly focuses on symptomatic supportive treatment, aiming to reduce intracranial pressure, ease pain, alleviate irritability, and fight infection. In this study, we summarized numerous studies covering the use of neuroprotective agents in different animal models and clinical trials after TBI. However, we found that no drug has been approved as specifically effective for the treatment of TBI. Effective therapeutic strategies for TBI remain an urgent need, and attention is turning toward traditional Chinese medicine. We analyzed the reasons why existing high-profile drugs had failed to show clinical benefits and offered our views on the research of traditional herbal medicine for treating TBI.

The Incidence of Takotsubo Cardiomyopathy in Patients with Intracerebral Hemorrhage: A US Nationwide Study

BACKGROUND

Takotsubo cardiomyopathy (TC) is a commonly observed complication among patients with intracerebral hemorrhage (ICH); however, the incidence of TC in patients with ICH have not been investigated yet. The goal of this study was to examine the incidence of TC in ICH and identify its risk factors, incidence rate, and outcomes of TC in patients with ICH in a US nationwide scale.

METHODS

Data for patients with ICH between the years of 2015 and 2018 were extracted from the Nationwide Inpatient Sample and stratified based on the diagnosis of TC.

RESULTS

Our results showed that the incidence rate of TC in ICH discharges was 0.27% (95% confidence interval [CI] 0.24-0.31). The mean age of patients with ICH developing TC was 66.28 years ± 17.11. There were significantly more women in the TC group, with an odds ratio (OR) of 3.65 (95% CI 2.63-5.05). Acute myocardial infarction (OR 7.91, 95% CI 5.80-10.80) was significantly higher in the TC group. The mortality rate of patients with ICH who had TC was significantly higher (33.48%, p < 0.0001). Length of stay (mean days; 15.72 ± 13.56 vs. 9.56 ± 14.10, p < 0.0001) significantly increased in patients with ICH who had TC. Patients with intraventricular ICH (OR 2.46, 95% CI 1.88-3.22) had the highest odds of TC.

CONCLUSIONS

Takotsubo cardiomyopathy is associated with a higher mortality, longer hospitalization period, and more acute myocardial infarctions in patients with ICH. It is illustrated that intraventricular ICH is associated with higher odds of TC.