Clinical case report of intractable paroxysmal sympathetic hyperactivity in TANGO2 deficiency disorder.

TANGO2 deficiency disorder (TDD) is a neurodegenerative disease characterized by a broad and variable spectrum of clinical manifestations, even among individuals sharing the same pathogenic variants. Here, we report a severely affected individual with TDD presenting with intractable paroxysmal sympathetic hyperactivity (PSH). While progressive brain atrophy has been observed in TDD, PSH has not been reported. Despite comprehensive workup for an acute trigger, no definite cause was identified, and pharmacological interventions were ineffective to treat PSH. Ultimately care was redirected to comfort measures. This article expands the clinical phenotype of patients with TDD, highlights the possibility of PSH in these patients, and the need for continued research for better treatments of TDD.

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.

Autonomic dysfunction and treatment strategies in intracerebral hemorrhage.

AIMS: Autonomic dysfunction with central autonomic network (CAN) damage occurs frequently after intracerebral hemorrhage (ICH) and contributes to a series of adverse outcomes. This review aims to provide insight and convenience for future clinical practice and research on autonomic dysfunction in ICH patients. DISCUSSION: We summarize the autonomic dysfunction in ICH from the aspects of potential mechanisms, clinical significance, assessment, and treatment strategies. The CAN structures mainly include insular cortex, anterior cingulate cortex, amygdala, hypothalamus, nucleus of the solitary tract, ventrolateral medulla, dorsal motor nucleus of the vagus, nucleus ambiguus, parabrachial nucleus, and periaqueductal gray. Autonomic dysfunction after ICH is closely associated with neurological functional outcomes, cardiac complications, blood pressure fluctuation, immunosuppression and infection, thermoregulatory dysfunction, hyperglycemia, digestive dysfunction, and urogenital disturbances. Heart rate variability, baroreflex sensitivity, skin sympathetic nerve activity, sympathetic skin response, and plasma catecholamine concentration can be used to assess the autonomic functional activities after ICH. Risk stratification of patients according to autonomic functional activities, and development of intervention approaches based on the restoration of sympathetic-parasympathetic balance, would potentially improve clinical outcomes in ICH patients. CONCLUSION: The review systematically summarizes the evidence of autonomic dysfunction and its association with clinical outcomes in ICH patients, proposing that targeting autonomic dysfunction could be potentially investigated to improve the clinical outcomes.

Role of Gabapentin in Traumatic Brain Injury: A Prospective Comparative Study.

Background: Traumatic brain injury (TBI) is a major cause of mortality among young individuals, accounting for 65% of deaths in road traffic accidents. Paroxysmal sympathetic hyperactivity (PSH) is a common syndrome associated with TBI. This study represents the first prospective investigation aimed at assessing the impact of gabapentin on TBI patients, focusing on the prevention of secondary brain injury and brain edema while enhancing the Glasgow Coma Scale (GCS). Materials and methods: The study was conducted from September 2019 to July 2021 after receiving ethical committee approval. It included adult ICU patients (≥18 years) with moderate and severe GCS. Patients below 18 years, death within 48 hours, non-consenting, pregnant females, and individuals allergic to gabapentin were excluded from the study. Patients were randomly allocated in two groups: study group received 300 mg of gabapentin orally twice daily and control group received multivitamin tablets twice daily. The treatment period spanned 2 weeks. Follow-up occurred in the ICU and continued for up to 3 months post-discharge, including telephonic conversations. Results: About 60 patients were involved for analysis. Significant differences were found in GCS change from admission to discharge, Glasgow Outcome Scale (GOS) at 30 and 90 days, PSH episodes, and sedation bolus per day. Glasgow Coma Scale change was 53% in the study group compared with 25% in the control group (p = 0.009). Mortality was significantly lower in the study group. Glasgow Outcome Scale change between 30 and 90 days showed a 25% improvement in cases and no change in controls (p = 0.001). Conclusion: This pioneering study underscores the potential of gabapentin in managing traumatic brain injuries. How to cite this article: Singh R, Ambasta S, Bais PS, Azim A, Kumar S, Upreti B, et al. Role of Gabapentin in Traumatic Brain Injury: A Prospective Comparative Study. Indian J Crit Care Med 2024;28(2):120-125.

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.

Takotsubo syndrome linked to paroxysmal sympathetic hyperactivity as a postoperative complication after brain tumor removal: a case report and literature review.

Paroxysmal sympathetic hyperactivity (PSH) is a relatively common syndrome typically observed following traumatic brain injury (TBI). It manifests through a combination of non-specific symptoms that collectively define its presentation. Linked to sympathetic hyperactivity, takotsubo syndrome is a cardiomyopathy marked by left ventricular dysfunction and may coincide with PSH. While various factors can lead to the simultaneous occurrence of these syndromes, a notably rare scenario involves their manifestation after brain tumor removal. The nonspecific nature of PSH symptoms and of the cardiac dysfunction in takotsubo syndrome pose challenges in accurately diagnosing these conditions in an intensive care unit (ICU) setting. They often overlap with more prevalent diagnoses like sepsis, pulmonary embolism, and acute heart failure. Thus, it is crucial for clinicians dealing with these patients to be aware that symptoms indicating sympathetic activity surge and left heart failure might prompt consideration of takotsubo syndrome and PSH. This study presents the case of an 8-year-old girl who developed takotsubo syndrome associated with sympathetic hyperactivity following the surgical removal of a bulbar tumor. To the best of our knowledge, this is the tenth case of PSH following brain tumor removal in a pediatric patient and the first reported case of occurrence of takotsubo linked to PSH after brain tumor removal. We offer a detailed account of the patient's clinical journey in the ICU, accompanied by a comprehensive review of relevant literature to identify similar cases. The significance of this case study lies in emphasizing the potential occurrence of takotsubo syndrome due to PSH and underscores the importance of early diagnosis and management due to their association with unfavorable clinical outcomes.

Paroxysmal Sympathetic Hyperactivity After Acquired Brain Injury: An Integrative Review of Diagnostic and Management Challenges.

Paroxysmal sympathetic hyperactivity (PSH) mainly occurs after acquired brain injury (ABI) and often presents with high fever, hypertension, tachycardia, tachypnea, sweating, and dystonia (increased muscle tone or spasticity). The pathophysiological mechanisms of PSH are not fully understood. Currently, there are several views: (1) disconnection theory, (2) excitatory/inhibitory ratio, (3) neuroendocrine function, and (4) neutrophil extracellular traps. Early diagnosis of PSH remains difficult, given the low specificity of its diagnostic tools and unclear pathogenesis. According to updated case analyses in recent years, PSH is now more commonly observed in patients with stroke, with tachycardia and hypertension as the main clinical manifestations, which is not fully consistent with previous data. To date, the PSH Assessment Measure tool is optimal for the early identification of PSH and stratification of symptom severity. Clinical strategies for the management of PSH are divided into three main points: (1) reduction of stimulation, (2) reduction of sympathetic excitatory afferents, and (3) inhibition of the effects of sympathetic hyperactivity on target organs. However, use of drugs and standards have not yet been harmonized. Further investigation on the relationship between PSH severity and long-term neurological prognosis in patients with ABI is required. This review aimed to determine the diagnostic and management challenges encountered in PSH after ABI.

In Ischemic Heart Disease, Reduced Sensitivity to Pressure at the Sternum Accompanies Lower Mortality after Five Years: Evidence from a Randomized Controlled Trial.

Background: Autonomic nervous system dysfunction (ANSD) is associated with negative prognosis of ischemic heart disease (IHD). Elevated periosteal pressure sensitivity (PPS) at the sternum relates to ANSD and sympathetic hyperactivity. Two previous observational case-control studies of the effect of reduction of PPS suggested lower all-cause mortality from IHD and stroke. We now used a specific daily, adjunct, non-pharmacological program of reduction of elevated PPS to test the hypothetical association between the intervention and reduced all-cause mortality in patients with stable IHD in a randomized controlled trial (RCT). Methods: We completed active (n = 106) and passive interventions (n = 107) and compared the five-year mortalities. We also compared the five-year individual all-cause mortality of each participant to approximately 35.000 members of the general population of Denmark. Pooling the mortality data from the active group of the RCT with the two preliminary studies, we registered the mortality following active intervention of 1.168 person-years, compared to 40 million person-years of the pooled general population. Results: We recorded fewer deaths of the active RCT intervention group than of the corresponding control group from the general population (p = 0.01), as well as of the passive RCT intervention group (p = 0.035). The meta-analysis of the three studies together demonstrated reduced 4.2-year all-cause mortality of 60% (p = 0.007). Conclusions: The test of the hypothetical effect of an intervention aimed at the attenuation of ANSD accompanied by a lowered PPS revealed reduced all-cause mortality in patients with stable IHD.

Clonidine safety and effectiveness in the management of suspected paroxysmal sympathetic hyperactivity post-traumatic brain injury: A retrospective cohort study.

INTRODUCTION: Traumatic brain injury (TBI) is a leading cause of mortality and morbidity worldwide. In addition, TBI may cause paroxysmal sympathetic hyperactivity (PSH), which is associated with poor clinical outcomes. This study aimed to evaluate the safety and effectiveness of clonidine in patients with TBI and suspected PSH. METHODS: A retrospective cohort study for critically ill patients with TBI with suspected PSH admitted to intensive care units (ICUs) from 1 May 2016 to 31 January 2020 at a tertiary academic medical center. Eligible patients were categorized based on clonidine use during their ICU stay (Clonidine group vs. Control group). The primary outcome was the improvement in functional outcomes during ICU stay, defined by a delta Glasgow Coma Score (GCS). Secondary outcomes included ICU and hospital length of stay, heart rate variation, and 90-day mortality. RESULTS: A total of 2915 patients were screened, of which 169 were included. Based on multiple regression analysis, patients who received clonidine showed better improvement in functional outcomes by a higher mean delta GCS than patients who did not (Beta Coeff. 0.41; CI: 0.07 - 0.74; P = 0.02). In addition, the patient's GCS upon ICU discharge and IV opioids requirement on day three were higher in the clonidine group than control (beta coefficient (95% CI): 0.18 (0.03, 0.32); p = 0.02 and beta coefficient (95% CI): 1.38 (0.24, 2.52); p = 0.02, respectively). No statistical differences were observed in any of the other secondary outcomes after adjusting for confounders. CONCLUSION: This study found that patients who received clonidine had better functional outcomes during their ICU stay, as shown by their delta GCS than those who did not. Other outcomes were similar between the groups. More data are needed to explore the role of clonidine in patients with TBI with suspected PSH.

m6A methyltransferase METTL3 contributes to sympathetic hyperactivity post-MI via promoting TRAF6-dependent mitochondrial ROS production.

OBJECTIVES: N6-methyladenosine (m6A) is the most prevalent post-translational modification in eukaryotic mRNA. Recently, m6A editing modified by methyltransferase-like enzyme 3 (METTL3), the core m6A methyltransferase, has been demonstrated to be involved in cardiac sympathetic hyperactivity. This study aimed to clarify the effects and underlying mechanisms of METTL3 in the paraventricular nucleus (PVN) in mediating sympathetic activity following myocardial infarction (MI). METHODS: We established rat MI models by left anterior descending coronary artery ligation. m6A quantification was performed.The expression of METTL3 and its downstream gene, tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6), were determined. The functional role of METTL3 in sympathetic hyperactivity and electrical conduction stability were verified by assessing renal sympathetic nerve activity (RSNA), norepinephrine (NE) levels, and programmed electrical stimulation. Rescue experiments were also conducted. The mechanism by which m6A is involved in mitochondrial reactive oxygen species (mROS) production, mediated by TRAF6/ECSIT pathway, was explored in lipopolysaccharide (LPS) treated primary microglial cells. RESULTS: METTL3 was predominantly localized in the microglia and significantly increased within the PVN at 3 days post-MI. Inhibition of METTL3 decreased m6A levels, TRAF6 expression, and mROS production; downregulated sympathoexcitation, indicated by attenuated NE concentration and RSNA; decreased the incidence of ventricular tachycardia or fibrillation; and improved cardiac function. Mechanistically, downregulation of METTL3 prevented TRAF6 translocation to the mitochondria in the microglia and subsequent TRAF6/ECSIT pathway activation, resulting in decreased mROS production. CONCLUSIONS: This study demonstrates that METTL3-mediated m6A modification promotes sympathetic hyperactivity through TRAF6/ECSIT pathway and mitochondrial oxidative stress in the PVN, thereby leading to ventricular arrhythmias post-MI.

Parental perspectives of episodic irritability in an ultra-rare genetic disorder associated with NACC1.

BACKGROUND: A recurrent de novo variant (c.892C>T) in NACC1 causes a neurodevelopmental disorder with epilepsy, cataracts, feeding difficulties, and delayed brain myelination (NECFM). An unusual and consistently reported feature is episodic extreme irritability and inconsolability. We now characterize these episodes, their impact on the family, and ascertain treatments that may be effective. Parents of 14 affected individuals provided narratives describing the irritability episodes, including triggers, behavioral and physiological changes, and treatments. Simultaneously, parents of 15 children completed the Non-communicating Children's Pain Checklist-Revised (NCCPC-R), a measure to assess pain in non-verbal children. RESULTS: The episodes of extreme irritability include a prodromal, peak, and resolving phase, with normal periods in between. The children were rated to have extreme pain-related behaviors on the NCCPC-R scale, although it is unknown whether the physiologic changes described by parents are caused by pain. Attempted treatments included various classes of medications, with psychotropic and sedative medications being most effective (7/15). Nearly all families (13/14) describe how the episodes have a profound impact on their lives. CONCLUSIONS: NECFM caused by the recurrent variant c.892C>T is associated with a universal feature of incapacitating episodic irritability of unclear etiology. Further understanding of the pathophysiology can lead to more effective therapeutic strategies.

Treatment of non-epileptic episodes of anxious, fearful behavior in adolescent juvenile neuronal ceroid lipofuscinosis (CLN3 disease).

Background: Recurrent non-epileptic episodes of frightened facial and body expression occur in more than half of post-adolescent patients with juvenile neuronal ceroid lipofuscinosis (JNCL, CLN3 disease). Clinically, the episodes look similar to the attacks of paroxysmal sympathetic hyperactivity (PSH) commonly seen following traumatic brain injury (TBI). The episodes occur when the patients are exposed to separation, hear loud sounds or are otherwise bothered by discomfort and as in PSH following TBI, the attacks are difficult to prevent and/or treat. Aim and methods: Based on present knowledge of triggering factors, the neural anxiety/fear circuit, its afferent and efferent pathways and documented CLN3 disease-impact on these tracks, the current study discusses a rational approach how to prevent and/or treat the attacks. Results: Patients with JNCL have a disturbed somatosensory modulation leading to a reduced threshold of pain; a degeneration within the neural anxiety/fear circuit leading to an imbalance of central network inhibition and excitation pathways; and finally, an, with advancing age, increasing autonomic imbalance leading to a significant dominance of the sympathetic neural system. Discussion: Theoretically, there are three points of attack how to prevent or treat the episodes: (1) increase in threshold of discomfort impact; (2) modulation of imbalance of central network inhibition and excitation, and (3) restoring the balance between the sympathetic and parasympathetic neural systems prompted by a parasympathetic withdrawal. As to (1) and (2), prevention should have the greatest priority. As regards (3), research of transcutaneous vagal stimulation treatment in JNCL is warranted.

Pupillographic Analysis of COVID-19 Patients: Early and Late Results After Recovery.

Objectives: We aimed to investigate the short- and long-term static and dynamic pupillary responses of patients recovered from coronavirus disease-19 (COVID-19) using quantitative infrared pupillography. Methods: This study included patients who recovered from COVID-19 (Group 1) and age- and gender-matched controls (Group 2). A detailed ophthalmic examination was performed at 1 month and 6 months after the diagnosis of COVID-19. Photopic, mesopic, and scotopic pupil diameters (PDs) were measured using a quantitative infrared pupillography which was integrated into Scheimpflug/Placido photography-based topography system. PDs at 0, 2nd, 4th, and 6th seconds, and average pupil dilation speeds at 2nd, 4th, 6th, and 8th seconds were recorded. Results: Eighty-six eyes of 86 patients (Group 1: n=42; Group 2: n=44) were included. While the mean photopic, mesopic, and scotopic PDs were significantly larger in the COVID-19 group than the control group in the 1st month (p=0.035, p=0.017, p=0.018, respectively), no statistically significant difference was found in the 6th month. Besides, average pupil dilation speeds and PDs at the 0, 2nd, 4th, and 6th seconds were not statistically significantly different between the two groups in the 1st month and 6th month. Conclusion: PDs were significantly larger in COVID-19 patients in all light intensities in the 1st month after COVID-19. However, pupillary dilation was transient, and no significant difference was found in the 6th month. We suggest that the transient pupillary dilation may be secondary to the autonomic nervous system dysfunction and/or optic nerve and visual pathways alterations following COVID-19.

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.

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.

Effect of propranolol and clonidine after severe traumatic brain injury: a pilot randomized clinical trial.

OBJECTIVE: To evaluate the safety, feasibility, and efficacy of combined adrenergic blockade with propranolol and clonidine in patients with severe traumatic brain injury (TBI). BACKGROUND: Administration of adrenergic blockade after severe TBI is common. To date, no prospective trial has rigorously evaluated this common therapy for benefit. METHODS: This phase II, single-center, double-blinded, pilot randomized placebo-controlled trial included patients aged 16-64 years with severe TBI (intracranial hemorrhage and Glasgow Coma Scale score ≤ 8) within 24 h of ICU admission. Patients received propranolol and clonidine or double placebo for 7 days. The primary outcome was ventilator-free days (VFDs) at 28 days. Secondary outcomes included catecholamine levels, hospital length of stay, mortality, and long-term functional status. A planned futility assessment was performed mid-study. RESULTS: Dose compliance was 99%, blinding was intact, and no open-label agents were used. No treatment patient experienced dysrhythmia, myocardial infarction, or cardiac arrest. The study was stopped for futility after enrolling 47 patients (26 placebo, 21 treatment), per a priori stopping rules. There was no significant difference in VFDs between treatment and control groups [0.3 days, 95% CI (- 5.4, 5.8), p = 1.0]. Other than improvement of features related to sympathetic hyperactivity (mean difference in Clinical Features Scale (CFS) 1.7 points, CI (0.4, 2.9), p = 0.012), there were no between-group differences in the secondary outcomes. CONCLUSION: Despite the safety and feasibility of adrenergic blockade with propranolol and clonidine after severe TBI, the intervention did not alter the VFD outcome. Given the widespread use of these agents in TBI care, a multi-center investigation is warranted to determine whether adrenergic blockade is of therapeutic benefit in patients with severe TBI. Trial Registration Number NCT01322048.

Etiology of anxious and fearful behavior in juvenile neuronal ceroid lipofuscinosis (CLN3 disease).

Background: Juvenile neuronal ceroid lipofuscinosis (JNCL, CLN3) is a childhood-onset neurodegenerative disease with prominent symptoms comprising a pediatric dementia syndrome. As in adult dementia, behavioral symptoms like mood disturbances and anxiety are common. In contrast to in adult dementia, however, the anxious behavioral symptoms increase during the terminal phase of JNCL disease. In the present study, the current understanding of the neurobiological mechanisms of anxiety and anxious behavior in general is addressed as will a discussion of the mechanism of the anxious behavior seen in young JNCL patients. Based on developmental behavioral points of view, known neurobiological mechanisms, and the clinical presentation of the anxious behavior, a theory of its etiology is described. Result and discussion: During the terminal phase, the cognitive developmental age of JNCL patients is below 2 years. At this stage of mental development individuals act primarily from a concrete world of consciousness and do not have the cognitive ability to encounter a normal anxiety response. Instead, they experience the evolutionary basic emotion of fear, and as the episodes typically are provoked when the adolescent JNCL patient is exposed to either loud sounds, is lifted from the ground, or separated from the mother/known caregiver, the fear can best be perceived as the developmental natural fear-response that appears in children 0-2 years of age. The efferent pathways of the neural fear circuits are mediated through autonomic, neuroendocrine, and skeletal-motor responses. The autonomic activation occurs early, is mediated through the sympathetic and parasympathetic neural systems, and as JNCL patients beyond puberty have an autonomic imbalance with a significant sympathetic hyperactivity, the activation of the autonomic nervous system results in a disproportionate high sympathetic activity resulting in tachycardia, tachypnea, excessive sweating, hyperthermia, and an increased atypical muscle activity. The episodes are thus phenotypically similar to what is seen as Paroxysmal Sympathetic Hyperactivity (PSH) following an acute traumatic brain injury. As in PSH, treatment is difficult and so far, no consensus of a treatment algorithm exists. Use of sedative and analgesic medication and minimizing or avoiding provocative stimuli may partly reduce the frequency and intensity of the attacks. Transcutaneous vagal nerve stimulation might be an option worth to investigate rebalancing the sympathetic-parasympathetic disproportion.

Rehabilitation Care of the Child with an Acute Severe Traumatic Brain Injury.

Children with traumatic brain injury (TBI) represent a unique and evolving population. Recovery and long-term prognosis are variable given the heterogeneity of ages, developmental stages, and types of injuries. This article summarizes important information regarding severe TBI epidemiology, pathophysiology, classification, and acute management. Early and longitudinal involvement of rehabilitation experts, such as pediatric physiatrists, is critical in managing complications and optimizing outcomes.

Paroxysmal Sympathetic Hypertension: An Underdiagnosed Entity or a Diagnostic Difficulty?

How to cite this article: Pratyusha K, Jindal A. Paroxysmal Sympathetic Hypertension: An Underdiagnosed Entity or a Diagnostic Difficulty? Indian J Crit Care Med 2023;27(2):151.