Pharmacological management of Dysautonomia following traumatic brain injury

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.

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.

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.

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.

Paroxysmal sympathetic hyperactivity during traumatic brain injury

Traumatic brain injury (TBI) is one of the leading causes of disability, morbidity, and mortality worldwide. Some of the more common etiologies of TBI include closed head injury, penetrating head injury, or an explosive blast head injury. Neuronal damage in TBI is related to both primary injury (caused by mechanical forces), and secondary injury (caused by the subsequent tissue and cellular damages). Recently, it has been well established that Paroxysmal Sympathetic Hyperactivity (PSH), also known as "Sympathetic Storm", is one of the main causes of secondary neuronal injury in TBI patients. The clinical manifestations of PSH include recurrent episodes of sympathetic hyperactivity characterized by tachycardia, systolic hypertension, hyperthermia, tachypnea with hyperpnea, and frank diaphoresis. Given the diverse manifestations of PSH and its notable impact on the outcome of TBI patients, we have comprehensively reviewed the current evidence and discussed the pathophysiology, clinical manifestations, time of onset and duration of PSH during TBI. This article reviews the different types of head injuries that most commonly lead to PSH, possible approaches to manage and minimize PSH complications in TBI and the current prognosis and outcomes of PSH in TBI patients.

Sepsis or sympathetics? Paroxysmal sympathetic hyperactivity after pontine stroke

A 64-year-old man from nursing home with a pontine stroke 3 months ago, ventilator-dependent, presented with episodic fever, tachycardia and tachypnoea occurring several times a day. He was evaluated for sepsis and pulmonary embolism and was treated empirically with broad-spectrum antibiotics. But these episodes persisted. Due to the episodic nature and typical symptoms of sympathetic overactivity, in the setting of prior brain injury, paroxysmal sympathetic hyperactivity was considered. His antibiotics were discontinued, and he was treated symptomatically with baclofen and bromocriptine, which resulted in a partial reduction of these episodes.

Pharmacological Management of Paroxysmal Sympathetic Hyperactivity: A Scoping Review

Paroxysmal sympathetic hyperactivity (PSH) occurs in ∼10% of patients following acute severe brain injury. While PSH is associated with worse outcomes, there are no clinical practice guidelines to inform treatment. We aimed to systematically review the literature on the pharmacological management of PSH. MEDLINE, Embase, and Cochrane library databases were searched from inception to August 2020. Eligible studies met the following criteria: 1) randomized controlled trials, non-randomized controlled trials (case control or controlled cohort), observational studies, case series, and case reports; 2) study population of adult and pediatric patients; 3) exposure to an acute neurological insult complicated by PSH (or historic synonym); 4) description of pharmacological treatment of PSH. Our search retrieved 2729 citations with 83 articles assessed for inclusion. After full text extraction, 56 manuscripts inclusive of 459 patients met eligibility criteria. We identified 31 case reports, 15 case series (152 patients), seven retrospective case control or cohort studies (212 patients), and three prospective observational studies (52 patients). Traumatic brain injury was the most common precipitating insult (407 patients), followed by hypoxic encephalopathy (72 patients) and intracranial hemorrhage (10 patients). There were 48 drugs from 22 classes prescribed for the management of PSH. The most frequently prescribed agents were benzodiazepines, β-blockers, opioids, α-2 agonists, and baclofen. However, route and dose of drug and subsequent outcome were inconsistently reported, such that no summary was possible. While a wide variety of drugs have been reported to treat PSH, there is a lack of even moderate-quality evidence to inform clinical decision making.

Dysautonomia and Clinical Outcome in Vegetative State

A dramatic disorder tentatively attributed to diencephalic-hypothalamic damage or dysfunction, dysautonomia, affects recovery from brain injury. Its incidence, correlation with etiology, and relevance as a predictor of outcome were retrospectively surveyed in 333 patients in vegetative state (VS) for more than 2 weeks at admission. Outcome was assessed according to the Glasgow Outcome Scale. Data were treated statistically by multi-variate analyses. Dysautonomia occurred in 26.1% of patients, with greater incidence among post-traumatic (31.9%) than non-traumatic (15.8%) patients. Outcome was worse among non-traumatic than post-traumatic patients irrespective of dysautonomia, and worst among non-traumatic patients with dysautonomia. Dysautonomia proved common among patients in VS (with incidence depending on etiology and age) and influenced the patients' outcome through mechanisms still to be defined, but conceivably mediated by diencephalic-hypothalamic unbalance.

Autonomic Hyperactivity

PURPOSE OF REVIEW

Autonomic hyperactivity is a relatively common consequence of severe acute brain injury and can also be seen with spinal cord and peripheral nerve disorders. This article reviews basic pathophysiologic concepts regarding autonomic hyperactivity, its various forms of clinical presentation, and practical management considerations.

RECENT FINDINGS

Paroxysmal sympathetic hyperactivity is most common after traumatic brain injury but can also occur after other forms of severe acute diffuse or multifocal brain injury. Formal criteria for the diagnosis and severity grading of paroxysmal sympathetic hyperactivity have now been proposed. A growing body of literature is beginning to elucidate the mechanisms underlying this disorder, but treatment remains based on observational data. Our mechanistic understanding of other distinct forms of autonomic hyperactivity, such as autonomic dysreflexia after traumatic spinal cord injury and dysautonomia after Guillain-Barré syndrome, remains rudimentary, yet clinical experience shows that their appropriate management can minimize the risk of serious complications.

SUMMARY

Syndromes of autonomic hyperactivity can result from injury at all levels of the neuraxis. Much more research is needed to refine our understanding of these disorders and guide optimal management decisions.

Transdermal opioid patch in treatment of paroxysmal autonomic instability with dystonia with multiple cerebral insults: A case report

RATIONALE

Paroxysmal autonomic instability with dystonia (PAID) is an underdiagnosed syndrome that describes a collection of symptoms following diverse cerebral insults, such as traumatic brain injury, hydrocephalus, hemorrhagic stroke, or brain anoxia. It is manifested by systemic high blood pressure, hyperthermia, tachycardia, tachypnea, diaphoresis, intermittent agitation, and certain forms of dystonia.

PATIENT CONCERNS

A semi-comatose 46-year-old man was transferred from the regional rehabilitation hospital with various complaints involving fluctuating vital signs, including uncontrolled hyperthermia, hypertension, tachycardia, and tachypnea, and dystonia in all extremities. The patient underwent brain surgery for astrocytoma in 1996. The patient also had a history of first ischemic stroke on the basal ganglia in 2008 and a second one in the same area in 2017.

DIAGNOSIS

The laboratory, electrocardiography, and radiologic findings were normal. Brain imaging indicated an old infarction on the basal ganglia with hydrocephalus. Tractography using diffusion tensor imaging showed discontinuity of multiple tracts, and electrophysiologic tests, such as evoked potentials, displayed an absent response. Based on the dysautonomic symptoms and brain evaluations, the physiatrist diagnosed the patient with PAID.

INTERVENTIONS

Bromocriptine, propranolol, and clonazepam were administered sequentially, but autonomic instability persisted. Then, intravenous opioid was administered, and fluctuations in body temperature, heart rate, and respiratory rate, as well as decerebrate-type dystonia were improved. However, simultaneously, drug-induced severe hypotension developed (systolic blood pressure, 57 mm Hg). Subsequently, a transdermal opioid (fentanyl) patch for PAID was applied once every 3 days.

OUTCOMES

Ultimately, all vital signs and dystonia were managed without further complications, and the patient was discharged.

LESSONS

A patient diagnosed with PAID following multiple cerebral insults was observed, whose condition was controlled by application of opioid patch rather than by intravenous or oral routes. A transdermal opioid patch, such as fentanyl patch, can thus be effective in the treatment of patients with PAID following multiple cerebral insults.

Paroxysmal Sympathetic Hyperactivity

Paroxysmal sympathetic hyperactivity (PSH) is a relatively common, but often unrecognized, complication of acute diffuse or multifocal brain diseases, most frequently encountered in young comatose patients with severe traumatic brain injury. It is presumed to be caused by loss of cortical inhibitory modulation of diencephalic and brain stem centers and possible additional maladaptive changes in the spinal cord that combine to produce exaggerated sympathetic responses to stimulation. The syndrome consists of repeated sudden episodes of tachycardia, tachypnea, hypertension, sweating, and sometimes fever and dystonic posturing. The diagnosis is clinical. Treatment includes reducing any external stimulation that can trigger the episodes, and starting abortive (e.g., intravenous morphine) and preventive medications (e.g., gabapentin, propranolol, clonidine). Prompt and adequate treatment of PSH may reduce the likelihood of secondary complications, such as dehydration, weight loss and malnutrition, and muscle contractures.

Organic features of autonomic dysregulation in paediatric brain injury - Clinical and research implications for the management of patients with Rett syndrome

Rett Syndrome (RTT) is a complex neurodevelopmental disorder with autonomic nervous system dysfunction. The understanding of this autonomic dysregulation remains incomplete and treatment recommendations are lacking. By searching literature regarding childhood brain injury, we wanted to see whether understanding autonomic dysregulation following childhood brain injury as a prototype can help us better understand the autonomic dysregulation in RTT. Thirty-one (31) articles were identified and following thematic analysis the three main themes that emerged were (A) Recognition of Autonomic Dysregulation, (B) Possible Mechanisms & Assessment of Autonomic Dysregulation and (C) Treatment of Autonomic Dysregulation. We conclude that in patients with RTT (I) anatomically, thalamic and hypothalamic function should be explored, (II) sensory issues and medication induced side effects that can worsen autonomic function should be considered, and (III) diaphoresis and dystonia ought to be better managed. Our synthesis of data from autonomic dysregulation in paediatric brain injury has led to increased knowledge and a better understanding of its underpinnings, leading to the development of application protocols in children with RTT.

Identification and Management of Paroxysmal Sympathetic Hyperactivity After Traumatic Brain Injury

Paroxysmal sympathetic hyperactivity (PSH) has predominantly been described after traumatic brain injury (TBI), which is associated with hyperthermia, hypertension, tachycardia, tachypnea, diaphoresis, dystonia (hypertonia or spasticity), and even motor features such as extensor/flexion posturing. Despite the pathophysiology of PSH not being completely understood, most researchers gradually agree that PSH is driven by the loss of the inhibition of excitation in the sympathetic nervous system without parasympathetic involvement. Recently, advances in the clinical and diagnostic features of PSH in TBI patients have reached a broad clinical consensus in many neurology departments. These advances should provide a more unanimous foundation for the systematic research on this clinical syndrome and its clear management. Clinically, a great deal of attention has been paid to the definition and diagnostic criteria, epidemiology and pathophysiology, symptomatic treatment, and prevention and control of secondary brain injury of PSH in TBI patients. Potential benefits of treatment for PSH may result from the three main goals: eliminating predisposing causes, mitigating excessive sympathetic outflow, and supportive therapy. However, individual pathophysiological differences, therapeutic responses and outcomes, and precision medicine approaches to PSH management are varied and inconsistent between studies. Further, many potential therapeutic drugs might suppress manifestations of PSH in the process of TBI treatment. The purpose of this review is to present current and comprehensive studies of the identification of PSH after TBI in the early stage and provide a framework for symptomatic management of TBI patients with PSH.

Management of Paroxysmal Sympathetic Hyperactivity with Dexmedetomidine and Propranolol Following Traumatic Brain Injury in a Pediatric Patient

We report a case of pharmacologic management of pediatric paroxysmal sympathetic hyperactivity (PSH) in a patient who experienced symptomatic resolution with dexmedetomidine and propranolol. Following a blunt traumatic subdural hematoma and diffuse axonal injury, an 8-year-old male developed PSH on approximately day 5 of the hospitalization. PSH symptoms identified in this patient were hyperthermia, tachycardia, posturing, and hypertension with associated elevations in intracranial pressure. Episodes of PSH continued to be observed despite appropriate titration of opiates, sedatives, and traditional blood pressure management. Dexmedetomidine and propranolol were subsequently initiated to attenuate acute episodes of PSH. A reduction in sedative requirements and improvement in symptoms followed, which facilitated successful extubation. The combination of propranolol and dexmedetomidine was followed by a decrease in the frequency and severity of acute episodes of PSH. After utilization of multiple treatment modalities to control PSH episodes in our patient, propranolol and dexmedetomidine may have helped attenuate PSH signs and symptoms.

Paroxysmal Sympathetic Hyperactivity After Severe Traumatic Brain Injury in Children: Prevalence, Risk Factors, and Outcome

OBJECTIVE

To describe paroxysmal sympathetic hyperactivity in pediatric patients with severe traumatic brain injury using the new consensus definition, the risk factors associated with developing paroxysmal sympathetic hyperactivity, and the outcomes associated with paroxysmal sympathetic hyperactivity.

DESIGN

Retrospective cohort study.

SETTING

Academic children's hospital PICU.

PATIENTS

All pediatric patients more than 1 month and less than 18 years old with severe traumatic brain injury between 2000 and 2016. We excluded patients if they had a history of five possible confounders for paroxysmal sympathetic hyperactivity diagnosis or if they died within 24 hours of admission for traumatic brain injury.

MEASUREMENTS AND MAIN RESULTS

Our primary outcome was PICU mortality. One hundred seventy-nine patients met inclusion criteria. Thirty-six patients (20%) had at least eight criteria and therefore met classification of "likelihood of paroxysmal sympathetic hyperactivity." Older age was the only factor independently associated with developing paroxysmal sympathetic hyperactivity (odds ratio, 1.08; 95% CI, 1.00-1.16). PICU mortality was significantly lower for those with paroxysmal sympathetic hyperactivity compared with those without paroxysmal sympathetic hyperactivity (odds ratio, 0.08; 95% CI, 0.01-0.52), but PICU length of stay was greater in those with paroxysmal sympathetic hyperactivity (odds ratio, 4.36; 95% CI, 2.94-5.78), and discharge to an acute care or rehabilitation setting versus home was higher in those with paroxysmal sympathetic hyperactivity (odds ratio, 5.59; 95% CI, 1.26-24.84; odds ratio, 5.39; 95% CI, 1.87-15.57, respectively). When paroxysmal sympathetic hyperactivity was diagnosed in the first week of admission, it was not associated with discharge disposition.

CONCLUSIONS

Our study suggests that the rate of paroxysmal sympathetic hyperactivity in patients with severe traumatic brain injury is higher than previously reported. Older age was associated with an increased risk for developing paroxysmal sympathetic hyperactivity, but severity of the trauma and the brain injury were not. For survivors of severe traumatic brain injury beyond 24 hours who developed paroxysmal sympathetic hyperactivity, there was a lower PICU mortality but also greater PICU length of stay and a lower likelihood of discharge home from the admitting hospital, suggesting that functional outcome in survivors with paroxysmal sympathetic hyperactivity is worse than survivors without paroxysmal sympathetic hyperactivity.

Autonomic dysfunction in the neurological intensive care unit

Autonomic dysfunction is common in neuro-critical care patients and may compromise the function of various organs. Among the many diseases causing or being associated with autonomic dysfunction are traumatic brain injury, cerebrovascular diseases, epilepsy, Guillain-Barré syndrome (GBS), alcohol withdrawal syndrome, botulism and tetanus, among many others. Autonomic dysfunction may afflict various organs and may involve hyper- or hypo-activity of the sympathetic or parasympathetic system. In this short overview, we address only a small number of neuro-intensive care diseases with autonomic dysfunction. In GBS, autonomic dysfunction is frequent and may account for increased mortality rates; rapid changes between sympathetic and parasympathetic hypo- or hyper-activity may cause life-threatening cardiovascular complications. Paroxysmal sympathetic hyperactivity occurs after brain injury, hypoxia and cerebrovascular and other events, causes paroxysmal tachycardia, hypertension, tachypnoea and hyperthermia and is associated with a poorer prognosis and prolonged intensive care treatment. Other, at times life-threatening autonomic complications with exaggerated sympathetic activity and compromised baroreflex sensitivity arise during the alcohol withdrawal syndrome triggered by abrupt cessation of alcohol consumption. Botulism and tetanus are examples of life-threatening autonomic dysfunction caused by bacterial neurotoxins. Common neurological diseases, such as epilepsy, stroke or subarachnoid haemorrhage, are also associated with autonomic dysfunction that can on occasion cause critical deterioration of disease severity and prognosis.

Heart Rate Variability Among Children With Acquired Brain Injury

Objective

To find evidence of autonomic imbalance and present the heart rate variability (HRV) parameters that reflect the severity of paroxysmal sympathetic hyperactivity (PSH) in children with acquired brain injury (ABI).

Methods

Thirteen children with ABI were enrolled and age- and sex-matched children with cerebral palsy were selected as the control group (n=13). The following HRV parameters were calculated: time-domain indices including the mean heart rate, standard deviation of all average R-R intervals (SDNN), root mean square of the successive differences (RMSSD), physical stress index (PSI), approximate entropy (ApEn); successive R-R interval difference (SRD), and frequency domain indices including total power (TP), high frequency (HF), low frequency (LF), normalized HF, normalized LF, and LF/HF ratio.

Results

There were significant differences between the ABI and control groups in the mean heart rate, RMSSD, PSI and all indices of the frequency domain analysis. The mean heart rate, PSI, normalized LF, and LF/HF ratio increased in the ABI group. The presence of PSH symptoms in the ABI group demonstrated a statistically significant decline of the SDNN, TP, ln TP.

Conclusion

The differences in the HRV parameters and presence of PSH symptoms are noted among ABI children compared to an age- and sex-matched control group with cerebral palsy. Within the ABI group, the presence of PSH symptoms influenced the parameters of HRV such as SDNN, TP and ln TP.

Feeding Intolerance in Children with Severe Impairment of the Central Nervous System: Strategies for Treatment and Prevention

Children with severe impairment of the central nervous system (CNS) experience gastrointestinal (GI) symptoms at a high rate and severity, including retching, vomiting, GI tract pain, and feeding intolerance. Commonly recognized sources of symptoms include constipation and gastroesophageal reflux disease. There is growing awareness of sources due to the impaired nervous system, including visceral hyperalgesia due to sensitization of sensory neurons in the enteric nervous system and central neuropathic pain due to alterations in the thalamus. Challenging the management of these symptoms is the lack of tests to confirm alterations in the nervous system as a cause of symptom generation, requiring empirical trials directed at such sources. It is also common to have multiple reasons for the observed symptoms, further challenging management. Recurrent emesis and GI tract pain can often be improved, though in some not completely eliminated. In some, this can progress to intractable feeding intolerance. This comprehensive review provides an evidence-based approach to care, a framework for recurrent symptoms, and language strategies when symptoms remain intractable to available interventions. This summary is intended to balance optimal management with a sensitive palliative care approach to persistent GI symptoms in children with severe impairment of the CNS.

Paroxysmal sympathetic hyperactivity: An entity to keep in mind

Paroxysmal sympathetic hyperactivity (PSH) is a potentially life-threatening neurological emergency secondary to multiple acute acquired brain injuries. It is clinically characterized by the cyclic and simultaneous appearance of signs and symptoms secondary to exacerbated sympathetic discharge. The diagnosis is based on the clinical findings, and high alert rates are required. No widely available and validated homogeneous diagnostic criteria have been established to date. There have been recent consensus attempts to shed light on this obscure phenomenon. Its physiopathology is complex and has not been fully clarified. However, the excitation-inhibition model is the theory that best explains the different aspects of this condition, including the response to treatment with the available drugs. The key therapeutic references are the early recognition of the disorder, avoiding secondary injuries and the triggering of paroxysms. Once sympathetic crises occur, they must peremptorily aborted and prevented. of the later the syndrome is recognized, the poorer the patient outcome.

Paroxysmal sympathetic hyperactivity: the storm after acute brain injury

A substantial minority of patients who survive an acquired brain injury develop a state of sympathetic hyperactivity that can persist for weeks or months, consisting of periodic episodes of increased heart rate and blood pressure, sweating, hyperthermia, and motor posturing, often in response to external stimuli. The unifying term for the syndrome-paroxysmal sympathetic hyperactivity (PSH)-and clear diagnostic criteria defined by expert consensus were only recently established. PSH has predominantly been described after traumatic brain injury (TBI), in which it is associated with worse outcomes. The pathophysiology of the condition is not completely understood, although most researchers consider it to be a disconnection syndrome with paroxysms driven by a loss of inhibitory control over excitatory autonomic centres. Although therapeutic strategies to alleviate sympathetic outbursts have been proposed, their effects on PSH are inconsistent between patients and their influence on outcome is unknown. Combinations of drugs are frequently used and are chosen on the basis of local custom, rather than on objective evidence. New rigorous tools for diagnosis could allow better characterisation of PSH to enable stratification of patients for future therapeutic trials.

Calming the Storm: Dysautonomia for the Pediatrician

Dysautonomia is a potentially life-threatening syndrome seen in many different types of brain injuries. It involves paroxysmal sympathetic hyperactivity and typically includes a constellation of symptoms, including: tachycardia, tachypnea, hyperthermia, hypertension, diaphoresis, hypertonia, and/or decerebrate or decorticate posturing. It is a clinical diagnosis of exclusion. A multimodal treatment approach is necessary including environmental modifications along with pharmacotherapy. Early management can help prevent comorbidities including secondary brain injury while also improving patient outcomes. This discussion serves as an overview of dysautonomia with a focus on management in the pediatric population including an example of a clinical algorithm and a review of the commonly used medications.

[High blood pressure during the autonomic crises in children in intensive care unit: Etiologic circumstances and modality therapeutic]

The dysautonomic (DC) or neurovegetative crisis remains an imperfectly known entity; it associates in a paroxysmal manner a reaction of sympathetic hyperreactivity that can lead to the prognosis. Our objective is to specify the etiological circumstances (DC) and their modality of treatment in pediatric intensive care unit.

MATERIALS-METHODS

Descriptive study on files of children admitted in the intensive care unit of 2010-2015 who presented a DC acquired during their hospitalization.

RESULTS

In total, 41 patients included with an average age of 56.92 months presented DC. Among the etiological circumstances Guillain-Barré syndrome and head trauma are noted. Observed symptoms occur on average at one week of admission; they are related to the consequences of DC. The manifestations are polymorphic: a systolic hypertension is present in all cases with an average PAS of 141.24±13.48mmHg, an average PAD of 86.80±11.01mmHg, a vasomotor disorder, a hyperthermia are noted. Cerebral anoxia post cardiac arrest in 4 patients preceded the onset of DC. Apart from the etiologic treatment, 39 patients were intubated with mechanical ventilation, sedated with morphinomimetic and benzodiazepine±lioresal (baclofen). Treatment of hypertension resulted in the administration of a central antihypertensive. Evolution is good in addition to 5 deaths related to neurovegetative disorders.

CONCLUSION

DC is a poorly understood situation in pediatric intensive care unit, and the circumstances of the disease are variable. The diagnosis must be made with careful consideration because the prognosis may be fatal.

Pain Assessment and Treatment in Children With Significant Impairment of the Central Nervous System

Pain is a frequent and significant problem for children with impairment of the central nervous system, with the highest frequency and severity occurring in children with the greatest impairment. Despite the significance of the problem, this population remains vulnerable to underrecognition and undertreatment of pain. Barriers to treatment may include uncertainty in identifying pain along with limited experience and fear with the use of medications for pain treatment. Behavioral pain-assessment tools are reviewed in this clinical report, along with other strategies for monitoring pain after an intervention. Sources of pain in this population include acute-onset pain attributable to tissue injury or inflammation resulting in nociceptive pain, with pain then expected to resolve after treatment directed at the source. Other sources can result in chronic intermittent pain that, for many, occurs on a weekly to daily basis, commonly attributed to gastroesophageal reflux, spasticity, and hip subluxation. Most challenging are pain sources attributable to the impaired central nervous system, requiring empirical medication trials directed at causes that cannot be identified by diagnostic tests, such as central neuropathic pain. Interventions reviewed include integrative therapies and medications, such as gabapentinoids, tricyclic antidepressants, α-agonists, and opioids. This clinical report aims to address, with evidence-based guidance, the inherent challenges with the goal to improve comfort throughout life in this vulnerable group of children.

Dexmedetomidine attenuates acute paroxysmal sympathetic hyperactivity

We evaluated the curative effect of dexmedetomidine on paroxysmal sympathetic hyperactivity (PSH) in a retrospective study of 72 PSH patients after neurosurgery. Our results showed that dexmedetomidine was superior to propofol for treatment of PSH with respect to: average time needed to reduce paroxysmal hypertension (PH) to <140/90 mmHg (29.03±8.86 vs. 42.0±14.77 min), average remission time of PH (3.97±1.73 vs. 5.65±1.51 min), PH remission rate (61.22±10.8% vs. 41.52±14.15%), PH duration (9.31±2.66 vs. 13.05±4.19 days), average time for body temperature to return to normal (10.62±4.14 vs. 15.31±4.58 days), average time for heartrate to return to normal (11.34±3.90 vs. 15.72±4.10 days), and average time of respiratory rate below 25 breaths per minute (BPM) (7.00±1.74 vs. 15.32±5.87 days). Multiple logistic regression analyses showed that dexmedetomidine did not protect against the recurrence of PSH. Age and Glasgow Coma Score were the main factors predicting PSH recurrence. There was no difference in Glasgow Outcome Score (GOS) between the two groups during the 6 months of postoperative follow-up (p>0.05). These data suggest dexmedetomidine effectively controls an acute attack of PSH, but it does not improve the long-term prognosis of patients compared with propofol.

Paroxysmal sympathetic hyperactivity in brainstem-compressing huge benign tumors: clinical experiences and literature review

Severe paroxysmal sympathetic overactivity occurs in a subgroup of patients with acquired brain injuries including traumatic brain injury, hypoxia, infection and tumor-related complications. This condition is characterized by sudden increase of heart rate, respiratory rate, blood pressure, body temperature and excessive diaphoresis. The episodes may be induced by external stimulation or may occur spontaneously. Frequent occurrence of this condition could result in secondary morbidities, therefore, should be diagnosed and managed insightfully. These symptoms could be confused with seizures or other medical conditions, leading to unnecessary treatment. Despite clinical significance of paroxysmal sympathetic hyperactivity (PSH), brain tumor-induced PSH has not been studied nearly. In this report, two cases of the PSH in patients with brainstem-compressing benign tumors were introduced. The most useful pharmacologic agents were opioid (e.g., fentanyl patch) in preventing PSH attack, and nonselective β-blocker (e.g., propranolol) in relieving the symptoms. Clinical experiences of the rare cases of benign tumor-induced PSH can be helpful as an essential basis for further research.

[A case of paroxysmal sympathetic storm after acute disseminated encephalomyelitis and hypoxic encephalopathy responding to clonidine hydrochloride]

We report the case of a 17-year-old woman with paroxysmal sympathetic storm (PSS), which was successfully treated with clonidine hydrochloride. The patient was hospitalized for acute disseminated encephalomyelitis in June 2006. Dysphagia led to severe aspiration pneumonia in September 2006, and she suffered cardiopulmonary arrest. She survived but had severe brain damage, with her brain MRI showing diffuse hypoxic encephalopathy. From October 2006, she had several episodes of profound tachypnea (> 60/min), tachycardia (160 to 170 beats/min), hypertension (> 140 mmHg), hyperthermia (39°C), and decerebrate posturing. During the attacks, the levels of catecholamines in the patient's blood and urine were markedly elevated. Accordingly, a diagnosis of PSS associated with hypoxic encephalopathy was made. Her PSS clearly improved after the administration of clonidine hydrochloride (900 μg/day). This case suggests that clonidine hydrochloride, an α2 blocker, may be one therapeutic option for PSS.

Morphine: An Effective Abortive Therapy for Pediatric Paroxysmal Sympathetic Hyperactivity After Hypoxic Brain Injury

Paroxysmal sympathetic hyperactivity (PSH) is a life-threatening condition characterized by hyperadrenergic activity and autonomic dysfunction. Also termed autonomic storms, PSH can occur after a variety of cerebral insults, most commonly traumatic brain injury. Limited pediatric literature is available, especially in patients with brain injury from hypoxia. No consensus exists for the terminology, diagnostic criteria, or treatment algorithm for PSH. Thus, the optimal management, including medication selection and dosing, remains unclear. We present the detailed treatment of a 9-year-old, African American male with hypoxic brain injury after pulseless arrest following status asthmaticus, who subsequently developed PSH. The patient began to experience episodes of tachycardia, hypertension, tachypnea, diaphoresis, rigidity, and dystonic posturing on hospital day 5. After ruling out other potential causes, a diagnosis of PSH was made. Episodes of PSH failed to respond to lorazepam or labetalol but were aborted successfully with morphine. Management of PSH after hypoxic brain injury required medications for acute treatment as well as for prevention of PSH. Morphine was found to be highly effective and safe for aborting the autonomic crises. Other agents more commonly described in the literature did not result in an adequate response and were associated with significant adverse effects. A combination of clonazepam, baclofen, and either propranolol or clonidine aided in reducing the frequency of episodes of PSH. We suggest using morphine for aborting severe episodes of PSH that do not respond to antihypertensive agents or benzodiazepines.

Propranolol for Paroxysmal Sympathetic Hyperactivity with Lateralizing Hyperhidrosis after Stroke

Brain injury can lead to impaired cortical inhibition of the hypothalamus, resulting in increased sympathetic nervous system activation. Symptoms of paroxysmal sympathetic hyperactivity may include hyperthermia, tachycardia, tachypnea, vasodilation, and hyperhidrosis. We report the case of a 41-year-old man who suffered from a left middle cerebral artery stroke and subsequently developed central fever, contralateral temperature change, and hyperhidrosis. His symptoms abated with low-dose propranolol and then returned upon discontinuation. Restarting propranolol again stopped his symptoms. This represents the first report of propranolol being used for unilateral dysautonomia after stroke. Propranolol is a lipophilic nonselective beta-blocker which easily crosses the blood-brain barrier and may be used to treat paroxysmal sympathetic hyperactivity.

Paroxysmal sympathetic hyperactivity in neurological critical care

Introduction:

Paroxysmal sympathetic hyperactivity (PSH) is a clinical disorder mainly caused by traumatic brain injury, stroke, encephalitis and other types of brain injury. The clinical features are episodes of hypertension, tachycardia, tachypnea, fever and dystonic postures. In this study, we described clinical profile and outcome of six patients of PSH admitted in neurocritical care unit.

Materials and Methods:

This was a prospective observational study conducted at neurology critical care unit of a tertiary care center. All patients admitted at neurology critical unit during 6-month period from August 2013 to January 2014 were screened for the occurrence of PSH. The clinical details and outcome was documented.

Results:

PSH was observed in 6 patients. Male to female ratio was 5:1. Mean age ± SD was 36.67 ± 15.19 years. The leading causes were traumatic brain injury (two patients), stroke (two patients) and Japanese encephalitis (JE) (one patient) and tuberculous meningitis (one patient).

Conclusion:

PSH is an unusual complication in neurocritical care. It prolonged the hospitalization and hampers recovery. The other life-threatening conditions that mimic PSH should be excluded. The association with JE and tuberculous meningitis was not previously described in literature.

Treatment Progress of Paroxysmal Sympathetic Hyperactivity after Acquired Brain Injury

Paroxysmal sympathetic hyperactivity (PSH) is a common complication of various acquired brain injuries such as traumatic brain injury, subarachnoid hemorrhage, anoxic brain injury, intracerebral hemorrhage, and others. It is manifested by tachycardia, hypertension, tachypnea, diaphoresis, and dystonic posturing. The development of PSH can prolong hospitalization and lead to secondary brain injury and even death. Despite the awareness of the serious clinical impact, there is no consensus on diagnostic criteria. Thus, misdiagnosis and delayed recognition is very common. Most of the current treatment programs come from case reports and small case series; there are very few large-scale randomized controlled trials. Generally accepted medications are opioids, β-blockers and gabapentin (usually used in combination). However, the efficacy of these drugs has not been systematically assessed. The purpose of this review is to determine the treatment strategies and drugs commonly used for PSH at the overall level.

Autonomic dysfunction syndromes after acute brain injury

The central autonomic nervous system (CAN) is a multifaceted, richly connected neural network incorporating the hypothalamus, its descending tracts through the brainstem, the insular cortex and down into the spinal cord. All levels of the CAN are susceptible to injury following traumatic brain injury (TBI), whether from focal or diffuse injury. Focal injuries would be expected to produce localized damage to CAN control centers, whereas the effects of diffuse injuries are presumed to be more diverse and/or widely distributed. As the combination of focal and diffuse injury following TBI can vary widely from one individual to the next, the impact of focal injuries is best understood with reference to the focal ischemic stroke literature. Subarachnoid hemorrhage (SAH), a common complication following TBI, also has predictable effects on autonomic control that can be understood with reference to spontaneous SAH literature. Finally, paroxysmal sympathetic hyperactivity (PSH), a syndrome incorporating episodes of heightened sympathetic drive and motor overactivity following minor stimulation, is discussed as an example of what happens when central inhibitory control of spinal cord autonomics is impaired.

Influence of intrathecal baclofen on the level of consciousness and mental functions after extremely severe traumatic brain injury: brief report

BACKGROUND

Whenever oral treatment or botulinum toxin injections fail to control severe spasticity, a trial with intrathecal baclofen is recommended no earlier than 1 year after brain injury. When irreversible contractures are to be avoided, such a trial might be done earlier. Some have briefly reported cognitive modifications with this treatment.

METHODS

During the trial period, intrathecal baclofen is continuously infused by a portable external pump through an intrathecal catheter. The daily dose is adjusted according to the clinical response. If the expected response is obtained by reduction of spasticity, a programmable pump is then implanted. Throughout the procedure, close neuropsychological follow-up is pursued.

RESULTS

Two persons with extremely severe brain injury and spasticity received a programmable pump less than 10 months after trauma. Unexpectedly, one emerged from the minimally conscious state and the other from post-traumatic amnesia.

CONCLUSIONS

Intrathecal baclofen should be considered within the first year after brain injury whenever spasticity does not respond to medication. ITB lessens the degree of spasticity which in turn facilitates care and, thus, has the potential to limit contractures. After severe brain injury, this treatment might trigger recovery from altered states of consciousness, improve cognition and facilitate rehabilitation.

Understanding paroxysmal sympathetic hyperactivity after traumatic brain injury

Background:

Paroxysmal sympathetic hyperactivity (PSH) is a condition occurring in a small percentage of patients with severe traumatic brain injury (TBI). It is characterized by a constellation of symptoms associated with excessive adrenergic output, including tachycardia, hypertension, tachypnea, and diaphoresis. Diagnosis is one of exclusion and, therefore, is often delayed. Treatment is aimed at minimizing triggers and pharmacologic management of symptoms.

Methods:

A literature review using medline and cinahl was conducted to identify articles related to PSH. Search terms included paroxysmal sympathetic hyperactivity, autonomic storming, diencephalic seizures, and sympathetic storming. Reference lists of pertinent articles were also reviewed and these additional papers were included.

Results:

The literature indicates that the understanding of PSH following TBI is in its infancy. The majority of information is based on small case series. The review revealed treatments that may be useful in treating PSH.

Conclusions:

Nurses play a critical role in the identification of at-risk patients, symptom complexes, and in the education of family. Early detection and treatment is likely to decrease overall morbidity and facilitate recovery. Further research is needed to establish screening tools and treatment algorithms for PSH.

Traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of death and disability in both children and adults. TBI is complex, as it involves injury to multiple brain areas caused by both the initial injury and secondary events. The most persistent sequelae of TBI are cognitive and behavioral, reflecting the fact that the preponderance of damage is to the frontal lobes. Although the sequence of recovery follows a pattern, TBI is a heterogeneous disorder and rehabilitation programs must be tailored to the needs of the individual and his or her social situation. Specific therapy approaches, environmental structure, and medications all play a role. Many of the emerging approaches to facilitating CNS plasticity can be applied.

Risk factors related to dysautonomia after severe traumatic brain injury

BACKGROUND

Dysautonomia after severe traumatic brain injury (TBI) is a clinical syndrome affecting a subgroup of survivors and is characterized by episodes of autonomic dysregulation and muscle overactivity. The purpose of this study was to determine the incidence of dysautonomia after severe TBI in an intensive care unit setting and analyze the risk factors for developing dysautonomia.

METHODS

A consecutive series of 101 patients with severe TBI admitted in a major trauma hospital during a 2-year period were prospectively observed to determine the effects of age, sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, admission Glasgow Coma Scale (GCS) score, injury severity score, emergency craniotomy, sedation or analgesia, diffuse axonal injury (DAI), magnetic resonance imaging (MRI) scales, and hydrocephalus on the development of dysautonomia. Risk factors for dysautonomia were evaluated by using logistic regression analysis.

RESULTS

Seventy-nine of the 101 patients met inclusion criteria, and dysautonomia was observed in 16 (20.3%) of these patients. Univariate analysis revealed significant correlations between the occurrence of dysautonomia and patient age, admission GCS score, DAI, MRI scales, and hydrocephalus. Sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, injury severity score, sedation or analgesia, and emergency craniotomy did not influence the development of dysautonomia. Multivariate logistic regression revealed that patient age and DAI were two independent predictors of dysautonomia. There was no independent association between dysautonomia and admission GCS score, MRI scales, or hydrocephalus.

CONCLUSIONS

Dysautonomia frequently occurs in patients with severe TBI. A younger age and DAI could be risk factors for facilitating the development of dysautonomia.

Hyperbaric oxygen therapy for traumatic brain injury: still an enigma

With their article on the use of HBOT for post TBI dysautonomia, Lv and colleagues discuss a novel use for this form of treatment. Although HBOT has been a part of our TBI treatment armamentarium for many years, its use remains a very controversial issue. In this commentary, the science and research studies behind HBOT for TBI are reviewed, hopefully leaving the reader with an adequate knowledge base to answer a patient or family's inquiries as to the usefulness of HBOT for TBI.