Assessment of autonomic dysfunction following spinal cord injury: rationale for additions to International Standards for Neurological Assessment

Characterizing preserved autonomic regulation following spinal cord injury: Methods of a novel concerted testing battery and illustrative examples of a new translationally focused data representation

Autonomic dysfunction is common after spinal cord injury, though differing from motor and sensory function, there are currently no established batteries of tests to comprehensively characterize these deficits. Further, while individual established autonomic tests have a long history and sound scientific background, translating these autonomic testing results to inform clinical understanding is a major barrier. Herein, we outline a battery of six laboratory autonomic tests which were carefully curated to collectively describe the ability of individuals with spinal cord injury to inhibit and recruit sympathetic activity through the injured spinal cord. Presenting normative control data in 23 uninjured individuals completing this testing battery, we further demonstrate the utility of extracting three key testing metrics for each test, comparing these control results to 11 individuals with spinal cord injury. Results demonstrate strong normality of data with testing psychometrics suggesting reliable reproducibility on repeat testing. Further, even in this preliminary sample of individuals with spinal cord injuries, clear differences begin to emerge. This illustrates the ability of this collective testing battery to characterize autonomic regulation after spinal cord injury. To aid in clinical translation, we further present a graphical representation, an autonomic phenotype, which serves as a snapshot of how normal or abnormal sympathetic inhibition and recruitment of activation may be after spinal cord injury. Utilizing these autonomic phenotypes, three example cases of individuals with spinal cord injury highlight evidence of varied degrees of autonomically complete spinal cord injury. Together, this represents a key advancement in our understanding of autonomic function after spinal cord injury.

Cardiac autonomic nervous activity during different sleep stages in individuals with spinal cord injury: The influence of physical training

OBJECTIVE

The present study assessed the influence of physical training on cardiac autonomic activity in individuals with spinal cord injury (SCI) during different sleep stages.

METHODS

Twenty-six volunteers were allocated into three groups: 9 sedentary individuals without SCI (control, CON); 8 sedentary tetraplegic individuals with chronic SCI (SED-SCI); 9 physically trained tetraplegic individuals with chronic SCI (TR-SCI). All participants underwent nocturnal polysomnography to monitor sleep stages: wakefulness, non-rapid eye movement (NREM) sleep (N1, N2, and N3 stages), and REM sleep. The electrocardiography data obtained during this exam were extracted to analyze the heart rate variability (HRV).

RESULTS

Sleep stages influenced HRV in the time [RR interval and root mean square of successive RR interval differences (RMSSD)] and frequency [low-frequency (LF) and high-frequency (HF) powers and LF-to-HF ratio] domains (P < 0.05). SED-SCI individuals showed unchanged HRV compared to CON (P > 0.05). When comparing the TR-SCI and SED-SCI groups, no significant differences in HRV were reported in the time domain (P > 0.05). However, in the frequency domain, more accentuated HF power was observed in TR-SCI than in SED-SCI individuals during the N2 and N3 stages and REM sleep (P < 0.05). Moreover, TR-SCI had higher HF power than CON during the N3 stage (P < 0.05).

CONCLUSIONS

TR-SCI individuals have greater HF power, indicative of parasympathetic modulation, than sedentary (injured or not injured) individuals during different sleep stages. Therefore, enhanced parasympathetic activity induced by physical training may improve cardiac autonomic modulation during sleep in individuals with chronic SCI.

Delayed Diagnosis of Spinal Cord Injury in a Patient With Intellectual Disability: A Case Report

Spinal cord injury (SCI) can cause neurogenic shock accompanied by bradycardia and hypotension. If no preceding traumatic episodes are apparent and the neurological examination is complicated by the patient's intellectual disability, SCI is likely to be overlooked. A 63-year-old man with intellectual disability presented to our hospital. The patient had fallen on the floor; however, no apparent head or neck trauma was observed. The patient returned home after confirming the absence of intracranial hematoma on computed tomography. However, the patient was re-admitted because of hypotension and bradycardia, and sick sinus syndrome was suspected. As the manifestations were motor weakness in the extremities and urinary retention, screening spinal magnetic resonance imaging revealed cervical cord injury and spondylosis. Cervical SCI related to a fall was suspected. Cervical decompression surgery and rehabilitation therapy contributed to the improved patient status. Herein, we report a case of intellectual disability in which SCI was initially overlooked. No severe preceding traumatic episode or intellectual disability of the patient could have led to overlooking SCI in our case. Clinicians should be cautious about this rare condition.

Heart Rate Variability-Based Prediction of Autonomic Dysreflexia After Spinal Cord Injury

Autonomic dysreflexia (AD) is a common autonomic complication of spinal cord injury (SCI) characterized by a sudden increase is blood pressure triggered by peripheral stimulation, such as bladder distention. Iatrogenic AD events often occur during various medical procedures including urodynamic assessments (UDSs) used to evaluate lower urinary tract (LUT) function in individuals with SCI. To date, there are no established clinical practices that would allow early detection of the development of episodes of AD. Heart rate variability (HRV) is a reliable and non-invasive metric for evaluating autonomic regulation of the cardiovascular system, with demonstrated utility in people with SCI during UDSs. We aim to provide a comprehensive evaluation of cardiovascular function during UDS-induced AD using ultra-short-term HRV analysis and identify changes in cardiovascular dynamics to predict the onset of AD. We assessed cardiovascular data in a total of 24 participants with sensorimotor complete SCI above T6 (17 males, 7 females, median age = 43 [36-50] years) who experienced AD during UDS. We used continuous electrocardiographic recordings to evaluate HRV in 60 sec overlapping windows during filling cystometry. The mean of "normal-to-normal" heartbeats (meanNN), its standard deviation (SDNN), and the root mean square of successive differences (RMSSD) were calculated and used in all subsequent analyses. We found that SDNN and RMSSD diminished during the early phase of bladder filling and sharply increased during AD. Using the lowest point of statistical variability in heart rate (i.e., SDNN), we were able to predict AD events within 240 sec (percentile 25-percentile 75: 172-339 sec) before the first systolic blood pressure peak after AD onset (sensitivity = 0.667; specificity = 0.875). Our results indicated a temporary increase in sympathetic activity during the early phase of bladder filling, which is followed by an increase in parasympathetic outflow to the heart when AD occurs. These findings have significant clinical implications that extend beyond the context of UDS and demonstrate the importance of identifying early changes in HRV in order to accurately predict AD episodes in people living with SCI.

Priorities, needs and willingness of use of nerve stimulation devices for bladder and bowel function in people with spinal cord injury (SCI): an Australian survey

STUDY DESIGN

Anonymous online survey OBJECTIVES: To investigate the priorities, needs and willingness to adopt nerve stimulation devices for managing neurogenic bladder and bowel function in people with spinal cord injury (SCI) living in Australia.

SETTING

Online survey of people living with SCI in Australia.

METHODS

This anonymous online survey used Qualtrics and was advertised via standard communication channels, such as advocacy groups representing the SCI community in Australia, social media, attending SCI sporting events and by word-of-mouth.

RESULTS

Responses from 62 individuals (32% female, 68% male) were included. Bladder emptying through urethra without catheter was the highest priority for bladder function. Reducing time required for bowel routines and constipation were the top priorities regarding bowel function. The highest concern for internal/implanted devices was the 4% chance of device surgical removal, while wearing wires under the clothes was the main concern for external devices. 53% of respondents were willing to trial an implanted nerve stimulation device, while 70% would trial an external device to improve and gain independence in bladder and bowel function.

CONCLUSION

The findings of this study highlighted the potential role in which nerve stimulation can have in addressing bladder and bowel dysfunction in people with SCI, and have also identified that there was a need for Australian physiotherapists to evaluate their role in bladder and bowel dysfunction. Results from this study can help guide further research in nerve stimulation devices for bladder and bowel dysfunction in people with SCI.

SPONSORSHIP

n/a.

Fever as a rare combined symptom of degenerative cervical myelopathy: a case report and literature review

A 60-year-old male patient complained of weakness of both legs for one year, intermittent fever for two months, up to 38.0 °C. Physical examination showed bilateral hyperreflexia of knee tendon and positive Hoffman sign on the right side. MR imaging of the cervical spine showed central herniation of the cervical 5-7 disc and compression of the spinal cord. The WBC was normal, C-reactive protein was 24.42mg/l, ESR was 55mm/h, TB antibody, anti acid staining and T-SPOT were negative. Autoantibody was negative and thyroid function was normal. The JOA score was 9 points. During the operation, the herniated disc tissue was taken out for pathological examination and bacterial culture. The posterior longitudinal ligament was removed and no abscess was found. The symptom of asthenia in both legs was relieved and fever disappeared. No growth of aerobe, anaerobe or tubercle bacilli was found in the culture of resected tissue. One year after the operation, the fever did not recur, JOA score increased to 14 points, and MR imaging showed no protrusion in cervical spinal canal. In this case, the fever disappeared after the operation for cervical spondylosis, which may be a special manifestation of sympathetic nerve stimulation or autonomic dysfunction by chronic compression of spinal cord.

Autonomic Cardiovascular Control, Psychological Well-Being, and Cognitive Performance in People With Spinal Cord Injury

PURPOSE

To examine associations between parameters of psychological well-being, injury characteristics, cardiovascular autonomic nervous system (ANS) control, and cognitive performance in persons with spinal cord injury (SCI) compared with age-matched uninjured controls. This is an observational, cross-sectional study including a total of 94 participants (52 with SCI and 42 uninjured controls: UIC). Cardiovascular ANS responses were continuously monitored at rest and during administration of the Paced Auditory Serial Addition Test (PASAT). Self-report scores on the SCI-Quality of Life questionnaires are reported for depression, anxiety, fatigue, resilience, and positive affect. Participants with SCI performed significantly more poorly on the PASAT compared with the uninjured controls. Although not statistically significant, participants with SCI tended to report more psychological distress and less well-being than the uninjured controls. In addition, when compared with uninjured controls, the cardiovascular ANS responses to testing were significantly altered in participants with SCI; however, these responses to testing did not predict PASAT performance. Self-reported levels of anxiety were significantly related to PASAT score in the SCI group, but there was no significant relationship between PASAT and the other indices of SCI-Quality of Life. Future investigations should more closely examine the relationship among cardiovascular ANS impairments, psychological disorders, and cognitive dysfunction to better elucidate the underpinnings of these deficits and to guide interventions aimed at improving physiological, psychological, and cognitive health after SCI. Tetraplegia, paraplegia, blood pressure variability, cognitive, mood.

Construct validity of the international standards to document remaining autonomic function after spinal cord injury (ISAFSCI) (1st edition)

STUDY DESIGN

Observational study.

OBJECTIVES

To assess the construct validity of the International Standards to Document Remaining Autonomic Function after Spinal Cord Injury (ISAFSCI) (2012 1st Edition).

SETTING

Two Canadian spinal cord injury (SCI) centers.

METHODS

Data were collected between 2011-2014. Assessments included the ISAFSCI, standardized measures of autonomic function and a clinical examination. Construct validity of ISAFSCI was assessed by testing a priori hypotheses on expected ISAFSCI responses to standard measures (convergent hypotheses) and clinical variables (clinical hypotheses).

RESULTS

Forty-nine participants with an average age of 45 ± 12 years were included, of which 42 (85.7%) were males, 37 (77.6%) had a neurological level of injury at or above T6, and 23 (46.9%) were assessed as having motor and sensory complete SCI. For the six General Autonomic Function component hypotheses, two hypotheses (1 clinical, 1 convergent) related to autonomic control of blood pressure and one clinical hypothesis for temperature regulation were statistically significant. In terms of the Lower Urinary Tract, Bowel and Sexual Function component of the ISAFSCI, all the hypotheses (5 convergent, 3 clinical) were statistically significant except for the hypotheses on female sexual items (2 convergent, 2 clinical), likely due to small sample size.

CONCLUSION

The construct validity of ISAFSCI (2012 1st Edition) for the General Autonomic Function component was considered to be weak while it was much stronger for the Lower Urinary Tract, Bowel and Sexual Function component based on a priori hypotheses. These results can inform future psychometric studies of the ISAFSCI (2021 2nd Edition).

High spinal cord injury precipitating syncope: a rare indication for pacemaker insertion

The current evidence for vasovagal syncope management is that cardiac pacing is only indicated in a highly select group of patients where symptoms can be linked to bradycardic episodes. High spinal cord injury can lead to autonomic dysfunction and sympathetic nervous system hypoactivity. A high spinal cord injury can theoretically precipitate profound bradycardia leading to haemodynamic instability and syncope. A patient in his 50s with a history of C2 spinal injury was admitted to our tertiary centre for management of what was initially thought to be septic shock causing hypotension and syncope. With evidence to suggest this patient's presentation may be profound reflex syncope in the context of unopposed parasympathetic signalling, consensus was reached to implant a permanent pacemaker. Remarkably, the patient's haemodynamics stabilised and there were no further episodes of syncope.

Predictors of hospital-acquired pressure injuries in patients with complete spinal cord injury: a retrospective case-control study

BACKGROUND

Despite current best practices, pressure injuries (PI) remain a devastating and prevalent hospital-acquired complication for patients with acute traumatic spinal cord injuries (SCIs). This study examined associations between risk factors for PI development in patients with complete SCI, such as norepinephrine dose and duration, and other demographic factors or lesion characteristics.

METHODS

This case-control study included adults with acute complete SCIs ASIA-A, who were admitted to a level-one trauma center between 2014-18. A retrospective review was implement using data on patient and injury characteristics, including age, gender, level of SCI (cervical vs. thoracic), Injury Severity Score (ISS), length of stay (LOS) and mortality; presence/absence of PI during their acute hospital stay; and treatment factors such as spinal surgery, mean arterial pressure (MAP) targets, and vasopressor treatment. Multivariable logistic regression evaluated associations with PI.

RESULTS

Eighty-two out of 103 eligible patients had complete data, and 30 (37%) developed PIs. Patient and injury characteristics, including age (Mean: 50.6; SD:21.3), location of SCI (48 cervical, 59%) and ISS (Mean 33.1; SD:11.8), did not differ between PI and non-PI groups. Logistic regression analysis revealed that male gender (OR:34.1; CI₉₅:2.3-506.5, p = 0.010) and increased LOS (log-transformed; OR:20.5, CI₉₅:2.8-149.9, p = 0.003) were associated with increased risk of PI. Having an order for a MAP > 80mmg (OR:0.05; CI₉₅:0.01-0.30, p = 0.001) was associated with a reduced risk of PI. There were no significant associations between PI and duration of norepinephrine treatment.

CONCLUSIONS

Norepinephrine treatment parameters were not associated with development of PI, suggesting that MAP targets should be a focus for future investigations for SCI management. Increasing LOS should highlight the need for high-risk PI prevention and vigilance.

Consequences of spinal cord injury on the sympathetic nervous system

Spinal cord injury (SCI) damages multiple structures at the lesion site, including ascending, descending, and propriospinal axons; interrupting the conduction of information up and down the spinal cord. Additionally, axons associated with the autonomic nervous system that control involuntary physiological functions course through the spinal cord. Moreover, sympathetic, and parasympathetic preganglionic neurons reside in the spinal cord. Thus, depending on the level of an SCI, autonomic function can be greatly impacted by the trauma resulting in dysfunction of various organs. For example, SCI can lead to dysregulation of a variety of organs, such as the pineal gland, the heart and vasculature, lungs, spleen, kidneys, and bladder. Indeed, it is becoming more apparent that many disorders that negatively affect quality-of-life for SCI individuals have a basis in dysregulation of the sympathetic nervous system. Here, we will review how SCI impacts the sympathetic nervous system and how that negatively impacts target organs that receive sympathetic innervation. A deeper understanding of this may offer potential therapeutic insight into how to improve health and quality-of-life for those living with SCI.

Unraveling quad fever: Severe hyperthermia after traumatic cervical spinal cord injury

PURPOSE

There are many infectious and inflammatory causes for elevated core-body temperatures, though they rarely pass 40 ℃ (104 ℉). The term "quad fever" is used for extreme hyperpyrexia in the setting of acute cervical spinal cord injuries (SCIs). The traditional methods of treating hyperpyrexia are often ineffective and reported morbidity and mortality rates approach 100%. This study aims to identify the incidence of elevated temperatures in SCIs at our institution and assess the effectiveness of using a non-invasive dry water temperature management system as a treatment modality with mortality.

METHODS

A retrospective analysis of acute SCI patients requiring surgical intensive care unit admission who experienced fevers ≥ 40 ℃ (104 ℉) were compared to patients with maximum temperatures < 40 ℃. Patients ≥18 years old who sustained an acute traumatic SCI were included in this study. Patients who expired in the emergency department; had a SCI without radiologic abnormality; had neuropraxia; were admitted to any location other than the surgical intensive care unit; or had positive blood cultures were excluded. SAS 9.4 was used to conduct statistical analysis.

RESULTS

Over the 9-year study period, 35 patients were admitted to the surgical intensive care unit with a verified SCI. Seven patients experienced maximum temperatures of ≥ 40 ℃. Six of those patients were treated with the dry water temperature management system with an overall mortality of 57.1% in this subgroup. The mortality rate for the 28 patients who experienced a maximum temperature of ≤ 40 ℃ was 21.4% (p = 0.16).

CONCLUSION

The diagnosis of quad fever should be considered in patients with cervical SCI in the presence of hyperthermia. In this study, there was no significant difference in mortality between quad fever patients treated with a dry water temperature management system versus SCI patients without quad fever. The early use of a dry water temperature management system appears to decrease the mortality rate of quad fever.

Effects of non-invasive spinal cord stimulation on lower urinary tract, bowel, and sexual functions in individuals with chronic motor-complete spinal cord injury: Protocol for a pilot clinical trial

INTRODUCTION

Electrical spinal cord neuromodulation has emerged as a leading intervention for restoring autonomic functions, such as blood pressure, lower urinary tract (LUT), bowel, and sexual functions, following spinal cord injury (SCI). While a few preliminary studies have shown the potential effect of non-invasive transcutaneous spinal cord stimulation (tSCS) on autonomic recovery following SCI, the optimal stimulation parameters, as well as real-time and long-term functional benefits of tSCS are understudied. This trial entitled "Non-invasive Neuromodulation to Treat Bladder, Bowel, and Sexual Dysfunction following Spinal Cord Injury" is a pilot trial to examine the feasibility, dosage effect and safety of tSCS on pelvic organ function for future large-scale randomized controlled trials.

METHODS AND ANALYSIS

Forty eligible participants with chronic cervical or upper thoracic motor-complete SCI will undergo stimulation mapping and assessment batteries to determine the real-time effect of tSCS on autonomic functions. Thereafter, participants will be randomly assigned to either moderate or intensive tSCS groups to test the dosage effect of long-term stimulation on autonomic parameters. Participants in each group will receive 60 minutes of tSCS per session either twice (moderate) or five (intensive) times per week, over a period of six weeks. Outcome measures include: (a) changes in bladder capacity through urodynamic studies during real-time and after long-term tSCS, and (b) resting anorectal pressure determined via anorectal manometry during real-time tSCS. We also measure assessments of sexual function, neurological impairments, and health-related quality of life using validated questionnaires and semi-structured interviews.

ETHICS AND DISSEMINATION

Ethical approval has been obtained (CREB H20-01163). All primary and secondary outcome data will be submitted to peer-reviewed journals and disseminated among the broader scientific community and stakeholders.

The susceptibility of cardiac arrhythmias after spinal cord crush injury in rats

High-level spinal cord injury (SCI) often interrupts supraspinal regulation of sympathetic input to the heart. Although it is known that dysregulated autonomic control increases the risk for cardiac disorders, the mechanisms mediating SCI-induced arrhythmias are poorly understood. Here, we employed a rat model of complete spinal cord crush injury at the 2nd/3rd thoracic (T2/3) level to investigate cardiac rhythm disorders resulting from SCI. Rats with T9 injury and naïve animals served as two controls. Four weeks after SCI, rats were implanted with a radio-telemetric device for electrocardiogram and blood pressure monitoring. During 24-h recordings, heart rate variability in rats with T2/3 but not T9 injury exhibited a significant reduction in the time domain, and a decrease in power at low frequency but increased power at high frequency in the frequency domain which indicates reduced sympathetic and increased parasympathetic outflow to the heart. Pharmacological blockade of the sympathetic or parasympathetic branches confirmed the imbalance of cardiac autonomic control. Activation of sympatho-vagal input during the induction of autonomic dysreflexia by colorectal distention triggered various severe arrhythmic events in T2/3 injured rats. Meanwhile, intravenous infusion of the β1-adrenergic receptor agonist, dobutamine, caused greater incidence of arrhythmias in rats with T2/3 injury than naïve and T9 injured controls. Together, the results indicate that high-level SCI increases the susceptibility to developing cardiac arrhythmias likely owing to compromised autonomic homeostasis. The T2/3 crush model is appropriate for studying abnormal cardiac electrophysiology resulting from SCI.

Cardiac arrhythmias six months following traumatic spinal cord injury

OBJECTIVE

To investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI.

DESIGN

A prospective observational study using continuous twenty-four-hour Holter monitoring.

SETTING

Inpatient rehabilitation unit of a university research hospital and patient home setting.

PARTICIPANTS

Fifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale.

OUTCOME MEASURES

Comparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring.

RESULTS

Bradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1-C8) and thoracic (T1-T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months.

CONCLUSIONS

At the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.

Pharmacologic and Acute Management of Spinal Cord Injury in Adults and Children

Purpose of Review

This review provides guidance for acute spinal cord injury (SCI) management through an analytical assessment of the most recent evidence on therapies available for treating SCI, including newer therapies under investigation. We present an approach to the SCI patient starting at presentation to acute rehabilitation and prognostication, with additional emphasis on the pediatric population when evidence is available.

Recent Findings

Further studies since the Surgical Timing in Acute Spinal Cord Injury Study (STASCIS) demonstrated a potential functional outcome benefit with ultra-early surgical intervention ≤ 8 h post-SCI. Subsequent analysis of the National Acute Spinal Cord Injury Study (NASCIS) II and NASCIS III trials have demonstrated potentially serious complications from intravenous methylprednisolone with limited benefit. Newer therapies actively being studied have demonstrated limited or no benefit in preclinical and clinical trials with insufficient evidence to support use in acute SCI treatment.

Summary

Care for SCI patients requires a multi-disciplinary team. Immediate evaluation and management are focused on preventing additional injury and restoring perfusion to the affected cord. Rapid assessment and intervention involve focused neurological examination, targeted imaging, and surgical intervention when indicated. There are currently no evidence-based recommendations for pathomechanistically targeted therapies.

Quad Fever in a Case of Cervical Cord Injury—A Rare Case Report

By definition, “quad fever” is an extreme elevation in body core temperature beyond 40.8°C (105.4°F) in a patient with spinal cord injury. This type of central nervous system hyperpyrexia is seen in spinal cord injury patients, particularly those with high cervical spine injury with quadriplegia. However, it has also been described in paraplegics with a mid- or higher level thoracic spine injury. The incidence of “quad fever” is rare, with the highest reported temperature being 44°C (111.2°F) with chronicled fatal outcomes.

Though the use of antipyretics is generally efficacious, they are considerably ineffective in treating the hyperpyrexia seen in this type of severe central autonomic thermodysregulation.

Here, we present a case of high cervical spine injury in a 24-year-old male. The trauma resulted in a C3–5 level cord contusion with incomplete quadriplegia (ASIA [American Spinal Cord Injury Association Impairment Scale] grade B). The patient developed high grade fever of 106°F within a week of admission postoperatively.

Pancultures were negative and the wound was clean. Despite treatment with higher antibiotics and an infection disease specialist's consult, no obvious etiology was found. Drug-induced fever and thyroid function tests were excluded in other less-common causes.

Based on the diagnosis of exclusion, “quad fever” was inferred as the cause. He had other signs of autonomic instability during the episodes such as bradycardia with hypotension.

Our patient showed an almost early response to treatment to betablockers and antipsychotics after failure to respond to antibiotics, mechanical hypothermia, and antipyretics.

Autonomic Dysreflexia After Hip Fractures Managed by Regional Anesthesia: A Case Report

Autonomic dysreflexia occurs after a spinal cord injury usually at the level of T6 or above, and its hallmark feature is exaggerated autonomic response to noxious stimuli resulting in uncontrolled hypertensive episodes with reflexive bradycardia that can be fatal if not controlled. We present a case highlighting regional anesthetic techniques, including peripheral nerve blocks, to ameliorate the symptoms of autonomic dysreflexia triggered by hip fractures in a 57-year-old woman with an old C5-C6 spinal cord injury before definitive hip surgery. The regional techniques described provide anesthesiologists with a simple strategy to potentially mitigate a life-threatening situation.

A comparative study between preoperative and postoperative conventional autonomic functions in congenital craniovertebral junction anomalies

Background

Autonomic nervous system (ANS) is invariably affected by craniovertebral junction (CVJ) anomalies. The usual presentation is sudden after trivial trauma. When symptomatic, most of this autonomic dysfunction is clearly elicited clinically with bedside tests. Nonetheless, ANS functionality in relatively less symptomatic or asymptomatic patients is not known as no studies exist.

Methodology:

We performed a longitudinal prospective study of 40 less symptomatic patients who underwent surgery with conventional autonomic function tests (AFT) in pre- and post-operative periods. Correlation of its association with such anomalies is studied.

Results:

All 40 had both pre- and post-operative clinical follow-up, pre-operative AFT, whereas only 22 patients had follow-up AFT. The mean age for the group was 32 years and male: female ratio was 2.3:1. Mean Nurick's grade was 1.8, whereas Barthel's index was 83.75%. Clinical improvement was seen in almost 98% at follow-up. Orthostatic test showed a significant association with Nurick's grade. Barthel's index was significantly associated with degree of compression. The mean follow-up was 17.4 months. Most conventional AFTs were significantly decreased in the preoperative period (P ≤ 0.01). Both parasympathetic and sympathetic tone improved on follow-up with better improvement later. Overall clinical involvement of ANS was seen in 22.5% whereas subclinical involvement in the form of AFT impairment was seen in 100%.

Conclusion:

There is a definite involvement of subclinical ANS in all patients of CVJ anomalies irrespective of their symptomatology. Knowing the extent of involvement in the preoperative period can help prognosticate, prioritize regarding surgery as well as correlate with the extent of improvement.

Reduced Reflex Autonomic Responses Following Intradetrusor OnabotulinumtoxinA Injections: A Pre-/Post-study in Individuals With Cervical and Upper Thoracic Spinal Cord Injury

Urodynamic studies (UDS) can provoke autonomic dysreflexia (AD) in individuals with spinal cord injury (SCI) at and above the sixth thoracic spinal segment potentially leading to profound vagally mediated heart rate (HR) reductions. In this study,¹ we test the hypothesis that intradetrusor onabotulinumtoxinA injections will improve HR and its variability (HRV) responses to UDS in individuals with cervical and thoracic SCI. A total of 19 participants with chronic SCI (5 women, mean age 42.5 ± 7.9 years) with confirmed neurogenic detrusor overactivity underwent UDS before (i.e., baseline) and 1 month after intradetrusor onabotulinumtoxinA (200 U) injections (post-treatment). Continuous electrocardiography and blood pressure (BP) recordings were used to assess RR-interval, time, and frequency domain metrics of HRV (a surrogate marker of autonomic nervous system activity), and AD pre- and post-treatment. UDS pre-treatment resulted in increased RR-interval as well as time and frequency domain metrics of HRV. Vagally mediated increases in high-frequency (HF) power during UDS were larger in participants with cervical compared to upper thoracic SCI. Post-treatment, UDS had no effect on RR-interval and significantly reduced instances of bradycardia. Furthermore, intradetrusor onabotulinumtoxinA injections significantly reduced time domain metrics of HRV and HF power responses to UDS across all participants. Changes in HRV during UDS could be a potential indicator of improved autonomic cardiovascular function following interventions such as intradetrusor onabotulinumtoxinA injections.

Topological network analysis of patient similarity for precision management of acute blood pressure in spinal cord injury

Background:

Predicting neurological recovery after spinal cord injury (SCI) is challenging. Using topological data analysis, we have previously shown that mean arterial pressure (MAP) during SCI surgery predicts long-term functional recovery in rodent models, motivating the present multicenter study in patients.

Methods:

Intra-operative monitoring records and neurological outcome data were extracted (n = 118 patients). We built a similarity network of patients from a low-dimensional space embedded using a non-linear algorithm, Isomap, and ensured topological extraction using persistent homology metrics. Confirmatory analysis was conducted through regression methods.

Results:

Network analysis suggested that time outside of an optimum MAP range (hypotension or hypertension) during surgery was associated with lower likelihood of neurological recovery at hospital discharge. Logistic and LASSO (least absolute shrinkage and selection operator) regression confirmed these findings, revealing an optimal MAP range of 76–[104-117] mmHg associated with neurological recovery.

Conclusions:

We show that deviation from this optimal MAP range during SCI surgery predicts lower probability of neurological recovery and suggest new targets for therapeutic intervention.

Funding:

NIH/NINDS: R01NS088475 (ARF); R01NS122888 (ARF); UH3NS106899 (ARF); Department of Veterans Affairs: 1I01RX002245 (ARF), I01RX002787 (ARF); Wings for Life Foundation (ATE, ARF); Craig H. Neilsen Foundation (ARF); and DOD: SC150198 (MSB); SC190233 (MSB); DOE: DE-AC02-05CH11231 (DM).

Spinal cord injury is a devastating condition that involves damage to the nerve fibers connecting the brain with the spinal cord, often leading to permanent changes in strength, sensation and body functions, and in severe cases paralysis. Scientists around the world work hard to find ways to treat or even repair spinal cord injuries but few patients with complete immediate paralysis recover fully.

Immediate paralysis is caused by direct damage to neurons and their extension in the spinal cord. Previous research has shown that blood pressure regulation may be key in saving these damaged neurons, as spinal cord injuries can break the communication between nerves that is involved in controlling blood pressure. This can lead to a vicious cycle of dysregulation of blood pressure and limit the supply of blood and oxygen to the damaged spinal cord tissue, exacerbating the death of spinal neurons. Management of blood pressure is therefore a key target for spinal cord injury care, but so far, the precise thresholds to enable neurons to recover are poorly understood.

To find out more, Torres-Espin, Haefeli et al. used machine learning software to analyze previously recorded blood pressure and heart rate data obtained from 118 patients that underwent spinal cord surgery after acute spinal cord injury.

The analyses revealed that patients who suffered from either low or high blood pressure during surgery had poorer prospects of recovery. Statistical models confirming these findings showed that the optimal blood pressure range to ensure recovery lies between 76 to 104-117 mmHg. Any deviation from this narrow window would dramatically worsen the ability to recover.

These findings suggests that dysregulated blood pressure during surgery affects to odds of recovery in patients with a spinal cord injury. Torres-Espin, Haefeli et al. provide specific information that could improve current clinical practice in trauma centers. In the future, such machine learning tools and models could help develop real-time models that could predict the likelihood of a patient’s recovery following spinal cord injury and related neurological conditions.

Correlation of neurological level and sweating level of injury in persons with spinal cord injury

Objective: Thermoregulatory dysfunction after spinal cord injury (SCI) impairs quality of life and predisposes persons to life-threatening sequela of heat-related illness (HRI) in conditions of high ambient temperature. SCI clinicians currently have no objective way to predict which persons are at greatest risk of HRI. Evaporative cooling via sweating is the body's most efficient mechanism of heat dissipation. The relationship between the neurological level of injury (NLOI) and the degree of sudomotor dysfunction is not well defined. This study examines the relationship between the NLOI and sweating level of injury (SwLOI). This information can assist SCI clinicians in identifying individuals with SCI who have most impaired sudomotor function and thus highest risk of HRI.Design: Observational.Setting: Human physiology laboratory.Participants: 10 persons with tetraplegia (TP), 14 with paraplegia (PP) and 10 able-bodied (AB).Intervention: Passive heat stress (1°C rise in core temperature) with sweat responses (SR) quantified with the starch iodine test.Outcome measures: The most caudal dermatomal level in which sweating was visualized was recorded as the SwLOI, which was compared to the NLOI. Minimum, maximum and median differences between NLOI and SwLOI were calculated.Results: Persons with tetraplegia demonstrated no SR. Persons with paraplegia demonstrated SR at a median of 1 level below NLOI. Able-bodied controls demonstrated sweating on all skin surface areas.Conclusions: Persons with motor complete tetraplegia lack evaporative cooling capacity through SR during passive heat stress predisposing them to HRI. Meanwhile, persons with paraplegia sweat on average 1 dermatomal level below their NLOI.

Cerebral Autoregulation during Postural Change in Patients with Cervical Spinal Cord Injury-A Carotid Duplex Ultrasonography Study

Patients with a spinal cord injury (SCI) frequently experience sudden falls in blood pressure during postural change. Few studies have investigated whether the measurement of blood flow velocity within vessels can reflect brain perfusion during postural change. By performing carotid duplex ultrasonography (CDU), we investigated changes in cerebral blood flow (CBF) during postural changes in patients with a cervical SCI, determined the correlation of CBF change with presyncopal symptoms, and investigated factors affecting cerebral autoregulation. We reviewed the medical records of 100 patients with a cervical SCI who underwent CDU. The differences between the systolic blood pressure, diastolic blood pressure, and CBF volume in the supine posture and after 5 min at 50° tilt were evaluated. Presyncopal symptoms occurred when the blood flow volume of the internal carotid artery decreased by ≥21% after tilt. In the group that had orthostatic hypotension and severe CBF decrease during tilt, the body mass index and physical and functional scores were lower than in other groups, and the proportion of patients with a severe SCI was high. The higher the SCI severity and the lower the functional score, the higher the possibility of cerebral autoregulation failure. CBF should be assessed by conducting CDU in patients with a high-level SCI.

Early Management of Spinal Cord Injury: WFNS Spine Committee Recommendations

Scientific knowledge today is being generated more rapidly than we can assimilate thus requiring continuous review of gold-standards for diagnosis and treatment of specific pathologies. The aim of this paper is to provide an update on the best early management of spinal cord injury (SCI), in order to produce acceptable worldwide recommendations to standardize clinical practice as much as possible.The WFNS Spine Committee voted recommendations regarding management of SCI based on literature review of the last 10 years. The committee stated 9 recommendations on 3 main topics: (1) clinical assessment and classification of SCI; (2) emergency care and early management; (3) cardiopulmonary management. American Spinal Injury Association impairment scale, Spinal Cord Independence Measure, and International Spinal Cord Injury Basic Pain Data Set are considered the most useful and feasible in emergency evaluation and follow-up in case of SCI. Magnetic resonance imaging is the most indicated examination to evaluate patients with symptomatic SCI. In early phase, correction of hypotension (systolic blood pressure < 90 mmHg), and bradycardia are strongly recommended. Surgical decompression should be performed as soon as possible with the ideal surgical time being within 8 hours for both complete and incomplete lesions.

Cardiovascular Autonomic Dysfunction in Spinal Cord Injury: Epidemiology, Diagnosis, and Management

Spinal cord injury (SCI) disrupts autonomic circuits and impairs synchronistic functioning of the autonomic nervous system, leading to inadequate cardiovascular regulation. Individuals with SCI, particularly at or above the sixth thoracic vertebral level (T6), often have impaired regulation of sympathetic vasoconstriction of the peripheral vasculature and the splanchnic circulation, and diminished control of heart rate and cardiac output. In addition, impaired descending sympathetic control results in changes in circulating levels of plasma catecholamines, which can have a profound effect on cardiovascular function. Although individuals with lesions below T6 often have normal resting blood pressures, there is evidence of increases in resting heart rate and inadequate cardiovascular response to autonomic provocations such as the head-up tilt and cold face tests. This manuscript reviews the prevalence of cardiovascular disorders given the level, duration and severity of SCI, the clinical presentation, diagnostic workup, short- and long-term consequences, and empirical evidence supporting management strategies to treat cardiovascular dysfunction following a SCI.

Ventricular arrhythmia during rehabilitation of cervical spinal cord injury

Patients with cervical spinal cord injury have a high incidence of cardiac arrhythmias, especially in the first 14 to 30 days after traumatic event (acute phase). Electrophysiological abnormalities described in the acute phase are most often bradycardia, which is spontaneous or triggered by various stimuli. In the chronic phase, varied arrhythmias are described, but ventricular arrhythmias as a result of autonomic dysregulation in chronic SCI are rare and isolated. We present the case of a patient with a C5-C6 incomplete spinal cord injury (ASIA-B grade) in which symptomatic ventricular arrhythmia is described one year after the traumatic event.

The Hypotensive Role of Acupuncture in Hypertension: Clinical Study and Mechanistic Study

As a component of traditional Chinese medicine (TCM), acupuncture has the potential to lower blood pressure (BP) in patients with hypertension. Emerging evidence indicates that the acupuncture-induced inhibition of high BP occurs through the activation of the pathway in the afferent, central, and efferent pathways. An increasing number of studies have demonstrated that acupuncture not only activates distinct brain regions under conditions of hypertension caused by an imbalance between the sympathetic and parasympathetic systems but also modulates neurotransmitters in related brain regions to alleviate the autonomic response. The activity of these pathways can be assessed by injecting agonists or inhibitors or by performing neurotomy. This review focuses on the clinical and mechanistic studies of acupuncture in modulating BP, which might provide a neurobiological foundation for the effects of acupuncture. Although many mechanisms underlying the effects of acupuncture on cardiovascular function have been identified, further investigation is warranted.

Resection of hip heterotrophic ossification leads to resolution of autonomic nervous system dysfunction in a patient with spinal Charcot arthropathy: a case report

INTRODUCTION

Patients with complete spinal cord injury (SCI) may develop concurrent sequalae that interact and share symptoms; thus, a careful approach to diagnosis and management of new symptoms is crucial.

CASE PRESENTATION

A patient with prior T4 complete SCI presented with progressive autonomic nervous system (ANS) dysfunction. The initial differential diagnosis included syringomyelia and lumbar Charcot arthropathy. He had comorbid heterotopic ossification (HO) of the left hip. Surprisingly, his autonomic symptoms resolved following resection of the HO. In hindsight, loss of motion through the hip caused by HO may have led to hinging through a previously asymptomatic lumbar Charcot joint, causing dysautonomia.

DISCUSSION

ANS dysfunction is a disabling sequela of complete SCI and has a broad differential diagnosis. Hip immobility may be an indirect and overlooked cause due to the mechanical relationship between the hip and the lumbar spine.

Development of a skin temperature map for dermatomes in individuals with spinal cord injury: a cross-sectional study

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

The aim of this study was to map the skin temperature (Tsk) of individuals with SCI and compare able-bodied individuals, and among the groups to demonstrate the effects of differences in the levels of injury (paraplegia and tetraplegia with high and low injuries).

SETTING

Outpatient clinic, Brazil.

METHODS

Individuals with tetraplegia (n = 20), paraplegia (n = 21), and able-bodied (n = 11) individuals were recruited. A noncontact infrared thermometer (IRT) was used to measure three times the Tsk at the forehead, and at the C2 to S2 dermatomes. Core body temperature was measured at the axilla using the IRT and three other clinical thermometers.

RESULTS

Autonomic regulation is impaired by the injury. A Tsk map was constructed for the three groups. Significant differences in the Tsk of dermatomes were observed when comparing individuals with SCI and the able-bodied at the following dermatomes: C3, C7, T2, T3, T8, T9, L1, L2, L4, and S2. When comparing individuals with tetraplegia and able-bodied individuals, the dermatomes that showed significant differences were C5, C6, C8, T1, T10, L3, and S1. Dermatomes C5-C7, and T5 showed significant differences between individuals with tetraplegia and those with paraplegia. For L5 and S1 in paraplegia significant differences were found when comparing high with low injury.

CONCLUSION

A Tsk map on dermatomes in individuals with SCI was implemented, and showed a significant difference between able-bodied. As temperature is a parameter for analyzing autonomic function, the study could benefit rehabilitation by providing baseline values when constructing clinical protocols.

Visuo-motor and interoceptive influences on peripersonal space representation following spinal cord injury

Peripersonal space (PPS) representation is modulated by information coming from the body. In paraplegic individuals, whose lower limb sensory-motor functions are impaired or completely lost, the representation of PPS around the feet is reduced. However, passive motion can have short-term restorative effects. What remains unclear is the mechanisms underlying this recovery, in particular with regard to the contribution of visual and motor feedback and of interoception. Using virtual reality technology, we dissociated the motor and visual feedback during passive motion in paraplegics with complete and incomplete lesions and in healthy controls. The results show that in the case of paraplegics, the presence of motor feedback was necessary for the recovery of PPS representation, both when the motor feedback was congruent and when it was incongruent with the visual feedback. In contrast, visuo-motor incongruence led to an inhibition of PPS representation in the control group. There were no differences in sympathetic responses between the three groups. Nevertheless, in individuals with incomplete lesions, greater interoceptive sensitivity was associated with a better representation of PPS around the feet in the visuo-motor incongruent conditions. These results shed new light on the modulation of PPS representation, and demonstrate the importance of residual motor feedback and its integration with other bodily information in maintaining space representation.

Effects of D‑Ala2, D‑Leu5‑Enkephalin pre‑ and post‑conditioning in a rabbit model of spinal cord ischemia and reperfusion injury

It has recently been revealed that during the aorta-clamped period, D-Ala², D-Leu⁵-Enkephalin (DADLE) infusion can protect the spinal cord against ischemia and reperfusion (I/R) injury. However, the protective effects of DADLE administration prior to ischemia or at the time of early reperfusion have not yet been investigated. Drug pre- or post-conditioning can serve as a more valuable clinical strategy. Therefore, the present study was designed to investigate the neuroprotective effect of DADLE infusion at different time intervals in order to determine the optimum time point for ischemic spinal cord protection. A total of 40 New Zealand white rabbits were randomly divided into 5 groups: Sham-operated (Sham), normal saline pre-conditioning (NS), DADLE per-conditioning (D_per), DADLE pre-conditioning (D_pre) and DADLE post-conditioning (D_post). All animals were subjected to spinal cord ischemia for 30 min followed by 48 h reperfusion. Hind limb motor functions were assessed according to the Tarlov criterion when the animals regained consciousness, 6, 24 and 48 h after reperfusion. Histological analysis and the number of viable α-motor neurons were also used to assess the extent of spinal cord injury. Compared with the NS group, the Tarlov scores and the number of normal neurons were significantly higher in the D_per group (P<0.05), which were consistent with the results of a previous study. In addition, the paraplegia rate and loss of normal motor neurons were lower in the DADLE per- and post-conditioning groups compared with the DADLE pre-conditioning; however, these were not statistically significant. DADLE 0.05 mg/kg administration at three time points all mitigated normal motor neuron injury in the anterior horn and decreased the paraplegia rates in rabbits. The therapeutic benefits appeared best in the post-conditioning group with DADLE, and worst in the pre-conditioning group.

Lessons learned from the pilot study of an orthostatic hypotension intervention in the subacute phase following spinal cord injury

Context: Following spinal cord injury (SCI) at the cervical or upper-thoracic level, orthostatic hypotension (OH) is observed in 13-100% of patients. This study aimed to test the feasibility of conducting a randomized controlled trial combining a dynamic tilt-table (Erigo^®) and functional electrical stimulation (FES) to mitigate OH symptoms in the subacute phase after SCI. Design: Pilot study. Setting: A tertiary rehabilitation hospital. Participants: Inpatients who had a C4-T6 SCI (AIS A-D) less than 12 weeks before recruitment, and reported symptoms of OH in their medical chart. Interventions: Screening sit-up test to determine eligibility, then 1 assessment session and 3 intervention sessions with Erigo^® and FES for eligible participants. Outcome measures: Recruitment rate, duration of assessment and interventions, resources used, blood pressure, and Calgary Presyncope Form (OH symptoms). Results: Amongst the 232 admissions, 148 inpatient charts were reviewed, 11 inpatients met all inclusion criteria, 7 participated in a screening sit-up test, and 2 exhibited OH. Neither of the two participants recruited in the pilot study was able to fully complete the assessment and intervention sessions due to scheduling issues (i.e. limited available time). Conclusion: This pilot study evidenced the non-feasibility of the clinical trial as originally designed, due to the low recruitment rate and the lack of available time for research in participant's weekday schedule. OH in the subacute phase after SCI was less prevalent and less incapacitating than expected. Conventional management and spontaneous resolution of symptoms appeared sufficient to mitigate OH in most patients with subacute SCI.

[Orthostatic hypotension in patients with posttraumatic cervical myelopathy]

AIM

To define the mechanism of formation of orthostatic hypotension in patients with traumatic tetraplegia.

MATERIAL AND METHODS

The study included 64 patients with chronic (more 6 month) and subacute (less 6 month) tetraplegia; the period of observation was about 30 days after admission to the rehabilitation center. Changes in the state of the autonomic nervous systems (heart rate variability at rest and head-up tilt test, sinus arrhythmia) were studied.

RESULTS

In the first 6 months, all patients, and after 6-12 months, one third of the patients experienced orthostatic hypotension, which was accompanied by lower values of the normalized sympatovagal index (LF_n/HF_n) 0.35 (0.260; 0.650) and expiratory-inspiratory coefficient (RR_max/RR_min) 1.09 (1.040; 1200). An increase in expiratory-inspiratory coefficient as a result of physical rehabilitation up to 1.16 (1.120; 1.24) was noted only in patients less than 6 months after injury.

CONCLUSION

Both sympathetic and parasympathetic parts of the autonomic nervous system are involved in the formation of orthostatic hypotension syndrome in patients with spinal tetraplegia.

Identification of clinically related requirements of a novel assistive device for people with a high spinal cord injury

People with spinal cord injuries (SCI), and particularly with high level lesions, can potentially lose the ability to effectively operate computers. The Multimedia Authoring and Management using your Eyes and Mind (MAMEM) project aims to design and produce a novel assistive device to support computer use by individuals with SCI and other disabilities. The solution harnesses eye tracking and brain waves, as measured by encephalography (EEG), to manipulate common computer functions. This paper describes the first step in the project, during which we defined clinically related requirements of the assistive device. These definitions were based on data from three sources: (1) a narrative review; (2) a focus group of SCI rehabilitation professionals; and (3) structured questionnaires administrated to potential computer users with SCI, addressing computer-use habits, barriers, and needs. We describe both the collection of data from each source and the clinically related requirements extracted. The novel three-source requirement assessment method is discussed, and the advantages and disadvantages of each data source are reported. In conclusion, we suggest that this approach makes it possible to organize, discuss, and prioritize the requirements, and to create a work program while planning the device. This increases our level of certainty that the efficacy and adequacy of the assistive device will be maximized, in terms of the clinical needs of users.

Spontaneous and Stimulus-Evoked Respiratory Rate Elevation Corresponds to Development of Allodynia in Spinal Cord-Injured Rats

Respiratory complications frequently accompany spinal cord injury (SCI) and slowed breathing has been shown to mitigate pain sensitivity. It is possible that elevated respiratory rates (RRs) signal the emergence of chronic pain after SCI. We previously validated the use of remote electric field sensors to noninvasively track breathing in freely behaving rodents. Here, we examined spontaneous (resting) and stimulus-evoked RRs as potential indices of mechanical hypersensitivity following SCI. Adult male Long-Evans rats received a lower thoracic hemisection or contusion SCI, or sham surgery, and underwent weekly assessments of mechanical and thermal sensitivity using the von Frey and Hargreaves tests, respectively. Resting RRs were recorded with remote sensors prior to nociception assays as well as 1 day post-surgery. Evoked RRs were quantified weekly in response to at-level mechanical stimulation provided by a small brush at various stimulation speeds, including those corresponding to the distinct tuning properties of a sub-population of cutaneous afferents known as C-low threshold mechanoreceptors. SCI rats developed mechanical hypersensitivity, which peaked 2-3 weeks after SCI. Compared with at baseline, hemisection SCI rats showed significantly heightened resting RRs at 1 day and 7 days post-injury, and the latter predicted development of pain hypersensitivity. In contusion SCI rats, resting RR increases were less substantial but occurred at all weekly time-points. Increases in brush-evoked RR coincided with full expression of hypersensitivity at 14 (hemisection) or 21 (contusion) days after SCI, and these effects were restricted to the lowest brush speeds. Our results support the possibility that early changes in RR may convey pain information in rats.

Comparison between esophageal and intestinal temperature responses to upper-limb exercise in individuals with spinal cord injury

STUDY DESIGN

Experimental study.

OBJECTIVE

Individuals with spinal cord injuries (SCI) may present with impaired sympathetic control over thermoregulatory responses to environmental and exercise stressors, which can impact regional core temperature (T_core) measurement. The purpose of this study was to investigate whether regional differences in T_core responses exist during exercise in individuals with SCI.

SETTING

Rehabilitation centre in Wakayama, Japan.

METHODS

We recruited 12 men with motor-complete SCI (7 tetraplegia, 5 paraplegia) and 5 able-bodied controls to complete a 30-min bout of arm-cycling exercise at 50% V̇O₂ peak reserve. T_core was estimated using telemetric pills (intestinal temperature; T_int) and esophageal probes (T_eso). Heat storage was calculated from baseline to 15 and 30 min of exercise.

RESULTS

At 15 min of exercise, elevations in T_eso (Δ0.39 ± 0.22 °C; P < 0.05), but not T_int (Δ0.04 ± 0.18 °C; P = 0.09), were observed in able-bodied men. At 30 min of exercise, men with paraplegia and able-bodied men both exhibited increases in T_eso (paraplegia: Δ0.56 ± 0.30 °C, P < 0.05; able-bodied men: Δ0.60 ± 0.31 °C, P < 0.05) and T_int (paraplegia: Δ0.38 ± 0.33 °C, P < 0.05; able-bodied men: Δ0.30 ± 0.30 °C, P < 0.05). T_eso began rising 7.2 min earlier than T_int (pooled, P < 0.01). Heat storage estimated by T_eso was greater than heat storage estimated by T_int at 15 min (P = 0.02) and 30 min (P = 0.03) in men with paraplegia. No elevations in T_eso, T_int, or heat storage were observed in men with tetraplegia.

CONCLUSIONS

While not interchangeable, both T_eso and T_int are sensitive to elevations in T_core during arm-cycling exercise in men with paraplegia, although T_eso may have superior sensitivity to capture temperature information earlier during exercise.

Microclimate evaluation of strap-based wheelchair seating systems for persons with spinal cord injury: A pilot study

STUDY PURPOSE

The purpose of this pilot study was to assess microclimate characteristics of two versions of a strap-based wheelchair seating system (perforated and solid straps) and to conduct preliminary microclimate comparisons of subjects' current wheelchair seating systems.

MATERIALS AND METHODS

In this pilot study, the microclimate properties of two variations (solid and perforated) of a strap-based seating system were compared with two commonly used seating systems. Six subjects sat on three different seating systems each for 100-min test periods, while temperature and relative humidity were measured with a single sensor adjacent to the skin-seat interface. Additionally, thermal images of the seat interface were collected before and after each test period.

RESULTS

The thermal images revealed that the maximum surface temperature of the solid-strap-based seating system was significantly lower than the other seating systems, -1.21 °C. (95% CI -2.11 to -0.30, p = 0.02), immediately following transfer out of the seat. Five minutes after transferring out of the seat, the perforated-strap seat was significantly cooler than the other seats -0.94 °C. (95% CI -1.59 to -0.30), p = 0.01, as was the solid-strap-based seat, -1.66 °C. (95% CI -2.69 to -0.63), p = 0.01. There were no significant differences in interface temperature or relative humidity measured with the single sensor near the skin-seat interface.

CONCLUSION

This pilot study offers preliminary evidence regarding the microclimate of the strap-based seating systems compared with other common seating systems. Clinically, the strap-based seating system may offer another option for those who struggle with microclimate management.

Neonatal spinal injury induces de novo projections of primary afferents to the lumbosacral intermediolateral nucleus in rats

•

Neonatal spinal injury induces dextran amine-labeled primary afferent projections to the sacral intermediolateral nucleus.

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Dextran amine-labeled afferent fibers form varicose terminals on the parasympathetic preganglionic neurons.

•

Dextran amine tends to be incorporated preferentially in dorsal root ganglion neurons with myelinated fibers.

•

De novo projections of myelinated afferents might contribute to the recovery of micturition following neonatal spinal injury.

Complete spinal transection in adult rats results in poor recovery of hind limb function and severe urinary bladder dysfunction. Neonatal rats with spinal cord transection, however, exhibit spontaneous and significant recovery of micturition control. A previous study in which biotinylated-dextran amine (BDA) was used as an anterograde tracer demonstrated that primary afferent fibers from the fifth lumbar dorsal root ganglion (DRG) project more strongly and make more terminals in the ventral horn after neonatal spinal cord transection at the mid-thoracic level. In the present study, we injected BDA into the sixth lumbar (L6) DRG of neonatally spinalized rats to label primary afferent fibers that include visceral afferents. The labeled fibers projected to the intermediolateral nucleus (IML) in the intermediate zone on ipsilateral side of the L6 spinal segment, whereas no projections to the IML were observed in sham-operated or intact rats. The BDA-labeled fibers of neonatally spinalized rats formed varicose terminals on parasympathetic preganglionic neurons in the IML. These findings suggest that some primary afferent projections from the L6 DRG to the IML appear after neonatal spinal cord transection, and these de novo projections might contribute to the recovery of autonomic function such as micturition following spinal cord injury in the neonatal stage.

Open surgery for haemorrhoids in persons with spinal cord injury

Study design

Pilot retrospective study on the outcome of open surgery for grade III and IV haemorrhoids in patients with SCI.

Objective

Haemorrhoids and anal fissures are common in patients with spinal cord injury (SCI). Grade I to III haemorrhoids are usually managed medically or by surgical ligation. Grade III and IV haemorrhoids are treated with surgical haemorrhoidectomy in the general population, but not in patients with SCI, most probably due to fear of complications.

Setting

Fondation Hopale, Berck-sur Mer, France.

Methods

The surgical database was searched for open haemorrhoidectomies performed between 2007 and 2016. Seventeen patients were included. There were mostly males with complete paraplegia, mean age: 50 years and mean time since injury: 15.9 years. Open haemorrhoidectomy (Milligan and Morgan) was performed for isolated haemorrhoids (n = 4), and combined with Leopold Bellan procedure (posterior anoplasty and internal sphincterotomy) for associated anal fissures (n = 13). Short-term follow-up was performed by the surgeon (post-operative weeks 2 and 6), long-term follow-up by telephone interview (mean 5.7 years, SD 1.9).

Results

At 6-weeks post-operative, no significant complications had occurred and all wounds had healed, however 1 patient had recurrence of anal fissure. At long-term follow-up, 75% of patients reported a significant improvement in anorectal symptoms. Recurrences were reported by 5 patients: 3 haemorrhoids (18%) and 2 anal fissures (25%). Anal incontinence occurred in 1 patient who required an anal plug. All patients maintained the same bowel programs as pre-operative.

Conclusions

Open surgery procedures were well tolerated and should be considered in persons with SCI.

Prediction of autonomic dysreflexia during urodynamics: a prospective cohort study

BACKGROUND

Autonomic dysreflexia is a severe and potentially life-threatening condition in patients with spinal cord injury, as it can lead to myocardial ischemia, brain hemorrhage, or even death. Urodynamic investigation is the gold standard to assess neurogenic lower urinary tract dysfunction due to spinal cord injury and reveal crucial pathological findings, such as neurogenic detrusor overactivity. However, neurogenic detrusor overactivity and urodynamic investigation are known to be leading triggers of autonomic dysreflexia. Therefore, we aimed to determine predictors of autonomic dysreflexia in individuals with spinal cord injury during urodynamic investigation.

METHODS

This prospective cohort study included 300 patients with spinal cord injuries and complete datasets of continuous non-invasive cardiovascular monitoring, recorded during same session repeat urodynamic investigation. We used logistic regression to reveal predictors of autonomic dysreflexia during urodynamic investigation.

RESULTS

We found that level of injury and presence of neurogenic detrusor overactivity were the only two independent significant predictors for autonomic dysreflexia during urodynamic investigation. A lesion at spinal segment T6 or above (odds ratio (OR) 5.5, 95% CI 3.2-9.4) compared to one at T7 or below, and presence of neurogenic detrusor overactivity (OR 2.7, 95% confidence interval (CI) 1.4-4.9) were associated with a significant increased odds of autonomic dysreflexia during urodynamic investigation. Both odds persisted after adjustment for age, sex, and completeness and stage of injury (adjusted OR (AOR) 6.6, 95% CI 3.8-11.7, and AOR 2.2, 95% CI 1.1-4.5, respectively). Further stratification by lesion level showed level-dependent significantly increased adjusted odds of autonomic dysreflexia, i.e., from C1-C4 (AOR 16.2, 95% CI 5.9-57.9) to T4-T6 (AOR 2.6, 95% CI 1.3-5.2), compared to lesions at T7 or below.

CONCLUSIONS

In patients with neurogenic lower urinary tract dysfunction due to spinal cord injury, autonomic dysreflexia is independently predicted by lesion level and presence of neurogenic detrusor overactivity. Considering the health risks associated with autonomic dysreflexia, such as seizures, stroke, retinal bleeding, or even death, we recommend both continuous cardiovascular monitoring during urodynamic investigation in all spinal cord-injured patients with emphasis on those with cervical lesions, and appropriate neurogenic detrusor overactivity treatment to reduce the probability of potentially life-threatening complications.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01293110 .

Autoimmune Neurological Conditions Associated With Zika Virus Infection

Zika virus (ZIKV) is an emerging flavivirus rapidly spreading throughout the tropical Americas. Aedes mosquitoes is the principal way of transmission of the virus to humans. ZIKV can be spread by transplacental, perinatal, and body fluids. ZIKV infection is often asymptomatic and those with symptoms present minor illness after 3 to 12 days of incubation, characterized by a mild and self-limiting disease with low-grade fever, conjunctivitis, widespread pruritic maculopapular rash, arthralgia and myalgia. ZIKV has been linked to a number of central and peripheral nervous system injuries such as Guillain-Barré syndrome (GBS), transverse myelitis (TM), meningoencephalitis, ophthalmological manifestations, and other neurological complications. Nevertheless, mechanisms of host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion about the possible mechanisms underlying the development of autoimmune neurological conditions associated with Zika virus infection.

Incidence and Natural Progression of Neurogenic Shock after Traumatic Spinal Cord Injury

Neurogenic shock, a distributive type of circulatory shock after spinal cord injury (SCI), results in profound hypotension. The consequent hemodynamic instability complicates clinical management, delays surgical intervention, and impacts neurological outcome. Moreover, the reported incidence of this condition varies significantly. We establish the true incidence of neurogenic shock by comparing the most common clinical definitions used to diagnose the condition. Further, we characterize the acute progression and recovery of neurogenic shock. Daily blood pressure, heart rate, and fluid management as well as vasopressor therapy and neurologic status were collected over 30 days from 84 adults admitted to our tertiary trauma center after cervical (n = 56) and thoracic (n = 28) SCI. We found that the reported incidence of neurogenic shock varied greatly depending on which clinical definition was applied. By using a novel combination of hemodynamic and laboratory criteria to define neurogenic shock, the calculated incidence (29% cervical SCI) in our sample most appropriately reflects the true incidence, finding that hypovolemia was the primary factor responsible for the inconsistency in incidence reports between studies. In addition, we found a characteristic decline in blood pressure after the first week post-injury and that fluid management is not currently an integral aspect of clinical management (all persons were treated at a net fluid intake ≤ zero). The results demonstrate the need for accurate identification of neurogenic shock through consistent and appropriate criteria, which is not only important from a clinical point of view, but also in establishing accurate epidemiology to responsibly allocate resources to its management.