Advancing spinal cord injury care through non-invasive autonomic dysreflexia detection with AI.

This paper presents an AI-powered solution for detecting and monitoring Autonomic Dysreflexia (AD) in individuals with spinal cord injuries. Current AD detection methods are limited, lacking non-invasive monitoring systems. We propose a model that combines skin nerve activity (SKNA) signals with a deep neural network (DNN) architecture to overcome this limitation. The DNN is trained on a meticulously curated dataset obtained through controlled colorectal distension, inducing AD events in rats with spinal cord surgery above the T6 level. The proposed system achieves an impressive average classification accuracy of 93.9% ± 2.5%, ensuring accurate AD identification with high precision (95.2% ± 2.1%). It demonstrates a balanced performance with an average F1 score of 94.4% ± 1.8%, indicating a harmonious balance between precision and recall. Additionally, the system exhibits a low average false-negative rate of 4.8% ± 1.6%, minimizing the misclassification of non-AD cases. The robustness and generalizability of the system are validated on unseen data, maintaining high accuracy, F1 score, and a low false-negative rate. This AI-powered solution represents a significant advancement in non-invasive, real-time AD monitoring, with the potential to improve patient outcomes and enhance AD management in individuals with spinal cord injuries. This research contributes a promising solution to the critical healthcare challenge of AD detection and monitoring.

Symptomatic Treatment of Myelopathy.

OBJECTIVE: This article discusses the effects of myelopathy on multiple organ systems and reviews the treatment and management of some of these effects. LATEST DEVELOPMENTS: Recent advances in functional electrical stimulation, epidural spinal cord stimulation, robotics, and surgical techniques such as nerve transfer show promise in improving function in patients with myelopathy. Ongoing research in stem cell therapy and neurotherapeutic drugs may provide further therapeutic avenues in the future. ESSENTIAL POINTS: Treatment for symptoms of spinal cord injury should be targeted toward patient goals. If nerve transfer for upper extremity function is considered, the patient should be evaluated at around 6 months from injury to assess for lower motor neuron involvement and possible time limitations of surgery. A patient with injury at or above the T6 level is at risk for autonomic dysreflexia, a life-threatening condition that presents with elevated blood pressure and can lead to emergent hypertensive crisis. Baclofen withdrawal due to baclofen pump failure or programming errors may also be life-threatening. Proper management of symptoms may help avoid complications such as autonomic dysreflexia, renal failure, heterotopic ossification, and fractures.

Differentiating essential hypertension from autonomic dysreflexia: a case report.

INTRODUCTION: Autonomic dysreflexia (AD), a condition of critically raised blood pressure, is a severe complication of spinal cord injury. Primary (essential) hypertension may present with similar blood pressure levels to AD, though the causes, pathophysiology, presentation and treatment will differ. CASE PRESENTATION: We report a case of a 74-year-old patient with a C1 spinal injury, who developed primary (essential) hypertension during her rehabilitation phase of care, requiring extensive investigations for autonomic dysreflexia. Despite this, no underlying cause was found; essential hypertension was subsequently confirmed with 24-hour ambulatory blood pressure monitoring. Treatment with an ACE inhibitor was introduced to good effect. DISCUSSION: Essential hypertension can affect patients with spinal injury, even though most patients with higher level injuries (particularly cervical spinal cord injuries) are expected to have low resting baseline hypotension. Relevant features of this are presented within this case; a set of criteria to differentiate essential hypertension from autonomic dysreflexia are also proposed.

Characterization of heart rate changes associated with autonomic dysreflexia during penile vibrostimulation and urodynamics.

STUDY DESIGN: Secondary data analysis. OBJECTIVES: To characterize autonomic dysreflexia (AD) associated heart rate (HR) changes during penile vibrostimulation (PVS) and urodynamic studies (UDS). SETTING: University-based laboratory. METHODS: We analyzed blood pressure (BP) and HR data, recorded continuously, from 21 individuals (4 females; median age 41 years [lower and upper quartile, 37; 47]; median time post-injury 18 years [7; 27]; all motor-complete spinal cord injury (SCI) except one; cervical SCI = 15, thoracic [T1-T6] SCI = 6), who underwent PVS (11/21) or UDS (10/21). RESULTS: Overall, 47 AD episodes were recorded (i.e. PVS = 37, UDS = 10), with at least one AD episode in each participant. At AD threshold, bradycardia was observed during PVS and UDS in 43% and 30%, respectively. At AD peak (i.e., maximum increase in systolic BP from baseline), bradycardia was observed during PVS and UDS in 65% and 50%, respectively. Tachycardia was detected at AD peak only once during UDS. Our study was limited by a small cohort of participants and the distribution of sex and injury characteristics. CONCLUSIONS: Our findings reveal that AD-associated HR changes during PVS and UDS appear to be related to the magnitude of systolic BP increases. Highly elevated systolic BP associated with bradycardia suggests the presence of severe AD. Therefore, we recommend cardiovascular monitoring (preferably with continuous beat-to-beat recordings) during PVS and UDS to detect AD early. Stopping assessments before systolic BP reaches dangerously elevated levels, could reduce the risk of life-threatening complications in this cohort.

Vertebral insufficiency fractures as a cause of autonomic dysreflexia in a patient with chronic tetraplegia: A case report.

Context: Osteoporosis is a known complication in spinal cord injury patients and can result in an increased risk of fractures and associated morbidity. Bone demineralization is most common in long bones below the level of injury. The pathogenesis is complex and not fully understood.Findings: We present the case of a 65-year-old male with chronic spinal cord injury who was found to have multiple vertebral compression fractures causing autonomic dysreflexia and new onset spasticity.Conclusion/Clinical Relevance: This case illustrates the need for improved awareness, diagnosis, and prevention for this disease process.

Accidental boosting in an individual with tetraplegia - considerations for the interpretation of cardiopulmonary exercise testing.

CONTEXT: Autonomic dysreflexia (AD), characterized by a transient increase in systolic blood pressure (BP), is experienced by individuals with spinal cord injury (SCI) and can be purposefully induced ('boosting') to counteract autonomic dysfunction that impairs cardiovascular responses to exercise. Herein, we demonstrate the impact of unintentional boosting observed during cardiopulmonary exercise testing (CPET) in an inactive male with SCI (C5, motor-complete). FINDINGS: On two separate occasions the individual performed a standard arm-crank CPET (1-min stages, 7W increase in resistance) following by a longer CPET (4-min stages, 12W increase in resistance), both to volitional exhaustion. The second CPET was performed to confirm the accuracy of exercise intensity prescription and verify peak exercise parameters. Immediately following the second CPET on the initial visit, the individual reported symptoms of AD, verified as a 58mmHg increase in systolic BP from baseline. Relative to the first CPET, performed only 35 min earlier, there were pronounced differences in peak exercise responses. In comparison to the longer CPET performed on the second visit without a concomitant episode of AD (thereby controlling for the type of CPET protocol administered), peak exercise outcomes were considerably elevated: power output (Δ19W), oxygen uptake (Δ3.61 ml·â€…kg·-1min-1), ventilation (Δ11.4 L ·min-1) and heart rate (Δ9 b·min-1). CONCLUSION/CLINICAL RELEVANCE: This case raises important considerations around the nuances of CPET in this population. In individuals susceptible to BP instability, the physiologically boosted state may explain a significant proportion of the variance in peak aerobic capacity and should be closely monitored before and after clinical CPET.

Seizures: A Rare Presentation of Autonomic Dysreflexia in a Young Adult with Complete Spinal Cord Injury.

BACKGROUND: Autonomic dysreflexia (AD) is a common complication for individuals with cervical or upper-mid thoracic spinal cord injury (SCI). It is a life-threatening emergency; however, it is rarely encountered by many emergency physicians, thus, ongoing awareness of the topic is necessary. CASE REPORT: An 18-year-old man with cervical spinal cord injury presented to the Emergency Department with headache, nausea, elevated blood pressure, and seizures. He was treated with antiepileptics and transferred to the pediatric intensive care unit (PICU). The PICU care team recognized AD as the cause of the seizure, secondary to a clogged suprapubic catheter causing overdistension of his bladder. Once replaced, over 1 liter of urine drained from his bladder and his autonomic symptoms resolved. He became hypotensive and required fluid resuscitation, but no further seizures occurred. Why Should an Emergency Physician Be Aware of This? Although rare, AD can result in seizures, intracerebral hemorrhage, or even death if not recognized or treated appropriately. Emergency physicians should recognize headaches, facial flushing, and sweating as early symptoms of AD, along with acute elevation in blood pressure (noting that baseline blood pressure may be lower in individuals with SCI). Management involves evaluating and treating noxious stimuli below the level of neurologic injury. Symptom management alone, without resolution of the underlying issue, can add to morbidity and mortality.

Autonomic dysreflexia associated with cervical spinal cord gliofibroma: case report.

BACKGROUND: Autonomic dysreflexia (AD) is an abnormal reflex of the autonomic nervous system normally observed in patients with spinal cord injury from the sixth thoracic vertebra and above. AD causes various symptoms including paroxysmal hypertension due to stimulus. Here, we report a case of recurrent AD associated with cervical spinal cord tumor. CASE PRESENTATION: The patient was a 57-year-old man. Magnetic resonance imaging revealed an intramedullary lesion in the C2, C6, and high Th12 levels. During the course of treatment, sudden loss of consciousness occurred together with abnormal paroxysmal hypertension, marked facial sweating, left upward conjugate gaze deviation, ankylosis of both upper and lower extremities, and mydriasis. Seizures repeatedly occurred, with symptoms disappearing after approximately 30 min. AD associated with cervical spinal cord tumor was diagnosed. Histological examination by tumor biopsy confirmed the diagnosis of gliofibroma. Radiotherapy was performed targeting the entire brain and spinal cord. The patient died approximately 3 months after treatment was started. CONCLUSIONS: AD is rarely associated with spinal cord tumor, and this is the first case associated with cervical spinal cord gliofibroma. AD is important to recognize, since immediate and appropriate response is required.

Autonomic dysreflexia and concurrent Horner's Syndrome: a rare presentation in a patient with spinal cord injury.

INTRODUCTION: Autonomic dysreflexia is an uninhibited sympathetic response evoked by a strong sensory input below the level of the injury in patients with spinal cord injury. As presented in this case, autonomic dysreflexia can be associated with unusual symptoms such as Horner's syndrome. CASE PRESENTATION: An 18-year-old man with a traumatic spinal cord injury (C7 AIS A) experienced symptoms of unilateral Horner's syndrome: miosis, ptosis and anhidrosis which occurred simultaneously with symptoms of autonomic dysreflexia: severe headache accompanied by increasing right-sided diaphoresis, flushing, blurred vision, and increased blood pressure. These symptoms were triggered by bladder distention and were resolved after catheterisation. DISCUSSION: The patient experienced a transient Horner's syndrome due to autonomic dysreflexia. Both Horner's syndrome and symptoms of autonomic dysreflexia resolved when eliminating the eliciting stimulus, indicating that Horner's syndrome occurred due to a transient pressure on the sympathetic fibres supplying the superior cervical ganglion. Autonomic dysreflexia may have caused increased pressure disrupting the sympathetic input, thus inducing unilateral miosis, ptosis, and facial anhidrosis.

Medical emergency: rash, headache and spinal cord injury.

A 49-year-old consultant medical oncologist, with a medical history of complete T5 spinal cord injury (March 1992) and long-term paralysis from the chest down, presented with shingles affecting the T7 dermatome. He also had a dull frontal headache, a feeling of agitation and increased blood pressure of 135/90 on a home blood pressure machine (higher than his usual blood pressure of 90/70). Having been taught about autonomic dysreflexia at the time of his initial spinal cord injury, he self-diagnosed autonomic dysreflexia caused by the noxious stimulus of shingles below his level of spinal cord injury. He self-administered a nifedipine 5 mg sublingual capsule to decrease his blood pressure before urgently seeing his general practitioner. Treatment of the shingles with acyclovir and analgesia successfully managed the problem and avoided hospital admission. This case highlights key aspects in treating autonomic dysreflexia and the value of doctor-patient partnership in doing so.

PRES secondary to autonomic dysreflexia: A case series and review of the literature.

Context: Autonomic dysreflexia (AD) is a complex syndrome seen in patients with spinal cord injuries (SCI) and can be life-threatening with a significant negative impact on the health of the individual. Posterior reversible encephalopathy syndrome (PRES) is thought to be caused, in part, by rapid elevations in blood pressure; leading to posterior cerebral circulatory edema. This can result in seizures, blindness and can progress to fatal intracranial hemorrhages.Findings: Here we present two cases of patients with SCI who developed PRES from AD. Each patient was correctly diagnosed, leading to appropriate treatment of the factors leading to their AD and subsequent resolution of their PRES symptoms.Conclusions/Clinical Relevance: In SCI patients who present with new seizures, visual deficits, or other neurologic signs, PRES should be considered as a part of the differential diagnosis as a good outcome relies on rapid recognition and treatment of AD.

Safety and preliminary efficacy of functional electrical stimulation cycling in an individual with cervical cord injury, autonomic dysreflexia, and a pacemaker: Case report.

Context: Functional electric stimulation (FES) cycling is a commonly used therapeutic exercise modality after spinal cord injury (SCI); however, additional precautions must be taken in certain situations. The purpose of this study was to develop and apply a safety monitoring protocol for autonomic dysreflexia (AD) during FES cycling and to determine if an interval-FES cycling program can be safe and beneficial to an individual with cervical SCI, a history of AD, and a non-dependent cardiac pacemaker.The participant was a 36-year-old male with C6 AIS-C SCI sustained 9 years earlier, intermittent AD, and implanted cardiac pacemaker. Ten sessions of interval-FES cycling were performed twice weekly for 5 weeks. Rating of perceived exertion (RPE), blood pressure (BP), oxygen saturation (O2sat), and heart rate (HR) were monitored before, after, and every 5 min during cycling. ECG and cardiac pacemaker were evaluated by a cardiologist after ending the program.Findings: The participant reported self-limited chills 27 times over 10 sessions (19 "light", 3 "moderate", 5 "sharp"). Chills coincided with BP increases 59% of the time and their magnitudes moderately correlated (r = 0.32). The ECG was determined to be normal and the pacemaker fully functional at the end of the study, while blood glucose decreased (111-105 mg/dl), HbA1c levels increased (5.5-5.9%), and resting BP decreased (118/84-108/66 mmHg).Conclusion/Clinical Relevance: A person with cervical SCI, symptomatic AD, and a non-dependent pacemaker can safely participate and benefit from the interval-FES cycling program provided adequate monitoring of symptoms and vital signs.

Diastolic blood pressure changes during episodes of autonomic dysreflexia.

Objective: The current diagnostic criteria of autonomic dysreflexia (AD) is based solely on systolic blood pressure (SBP) increases from baseline without regard to changes in diastolic blood pressure (DBP). During urodynamics in persons with SCI at or above the sixth thoracic level (T6), we evaluated diastolic blood pressure (DBP) changes related with AD episodes.Design: Retrospective review of blood pressures recorded during urodynamics.Setting: Outpatient SCI urology program in a free standing rehabilitation center.Participants: Persons with spinal cord injury at or above the T6 level.Interventions: Urodynamic procedures performed between August 2018 to January 2019, as well as their prior testing for up to 10 years.Outcome Measures: Systolic and diastolic blood pressures were recorded during the procedure and episodes of AD defined as SBP >20 mmHg above baseline.Results: Seventy individuals accounting for 282 urodynamic tests were reviewed. AD occurred in 43.3% (122/282) of all urodynamics tests. The mean maximum SBP and DBP increase from baseline for those with AD were 35.5 ± 10.9 mmHg and 19.0±9.4 mmHg, respectively. There was a concomitant rise of DBP >10 mmHg with a SBP rise of >20 mmHg in 76.2% (93/122) of urodynamic tests. An elevation of DBP >10 mmHg was recorded in 23.8% (38/160) of urodynamics that did not have AD by the SBP definition.Conclusion: DBP increments of >10 mmHg with concurrent SBP increases of >20 mmHg occurs in the majority of AD episodes. Given the significance of cardiovascular complications in chronic SCI, further work is warranted to determine the significance of DBP elevations for defining AD.

Takotsubo cardiomyopathy in a chronic spinal cord injury patient with autonomic dysreflexia: A case report.

Context: Takotsubo cardiomyopathy (TC) is a transient stress-induced cardiomyopathy with left ventricular dysfunction of unknown etiology. A well accepted theory for the pathophysiology of TC is attributed to a massive catecholamine release [1]. This case report will review a chronic tetraplegia patient who was diagnosed with TC after a severe episode of autonomic dysreflexia (AD). He experiences mild episodes of AD several times a day; however, he had never experienced the severity of symptoms that was associated with this episode which led to his hospitalization. Autonomic dysreflexia is a syndrome of imbalanced sympathetic input secondary to loss of descending central sympathetic control in spinal cord injury due to noxious stimuli below the level of the injury, which occurs when the injury level is at thoracic level 6 (T6) or above [2].Findings: In this specific case, it is presumed that the massive catecholamine release associated with this severe AD episode resulted in TC. Although TC has been diagnosed after other instances of acute stress, it is unknown for it to be diagnosed after AD in a chronic setting.Clinical Relevance: The long-term effects of AD have not been well studied, and this case illustrates the importance of education to recognize and manage AD in the spinal cord patient who frequently has episodes of AD.

Discitis following urinary tract infection manifesting as recurrent autonomic dysreflexia related to truncal movements in a person with tetraplegia.

A 44-year-old male person with tetraplegia (C-5 AIS-A (American Spinal Cord Injury Association Standard Neurological Classification of Spinal Cord Injury Impairment Scale)) developed urinary tract infection and received appropriate antibiotic. Subsequently, he started sweating and shivering when he was sitting up; these symptoms resolved while lying on his back. Autonomic dysreflexia triggered by truncal movements continued to occur for 3 months. CT of the spine showed L5-S1 discitis. MRI of the spine showed diffuse marrow oedema in L5 and S1 vertebrae and a large abscess at L5/S1 level. Blood culture yielded Serratia marcescens sensitive to meropenem. Meropenem followed by ertapenem was given for 12 weeks. After 11 months, MRI showed resolution of discitis and epidural collection. The patient was able to sit up for 9 hours without developing autonomic dysreflexia. If a person with cervical spinal cord injury develops posture-related autonomic dysreflexia (eg, in sitting position, lying on sides or while hoisted), disco-vertebral pathology should be suspected.

Attenuation of autonomic dysreflexia during functional electrical stimulation cycling by neuromuscular electrical stimulation training: case reports.

INTRODUCTION: Spinal cord injury (SCI) may cause impairments of the motor, sensory, and autonomic nervous systems, which result in adverse changes in body composition and cardiovascular health. Functional electrical stimulation (FES) cycling may provide an effective alternative approach to perform exercise and improve cardiovascular health after SCI. Persons with an injury at or above T6 level are at high risk of developing a life-threatening complication of autonomic dysreflexia (AD). CASE PRESENTATION: Two participants with motor-complete C6 SCI completed either 12 weeks of passive range of motion or surface neuromuscular electrical stimulation (NMES) resistance training, followed by 12 weeks of functional electrical stimulation (FES) lower extremity cycling for both participants. Systolic and diastolic blood pressure (BP) were measured to determine the effects of NMES-resistance training and FES-lower extremity cycling during rest and exercise. DISCUSSION: The difference between mean value of BP during FES-lower extremity cycling exercise and resting BP averaged for 24 sessions was smaller for participant A (31.25 mmHg for systolic BP and 10.44 mmHg for diastolic BP), who received NMES-resistance training, as compared with participant B (58.62 mmHg for systolic BP and 35.07 mmHg for diastolic BP). The results of these case reports suggest that 12 weeks of NMES-resistance training preceding FES-lower extremity cycling may attenuate the development of AD after SCI. Risk of AD, triggered by noxious stimuli, may be dampened with FES-lower extremity cycling training in persons with SCI.

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.