A case report of three people experiencing intractable autonomic dysreflexia following instillation of Uro-Tainer® Polyhexanide 0.02.

INTRODUCTION: Historically, bladder washouts were used to instil therapeutic reagents directly into the bladder. This practice has expanded to include instillation of solutions that deal with catheter issues such as encrustation or formation of bio-film. They appear to provide a promising strategy for people with long term catheters. These products are readily available to purchase, but there is concern that people are using these solutions without a complete understanding of the purpose for the rinse and without clinical guidance to monitor response to treatment. CASE PRESENTATION: These case studies include three people living with spinal cord injury (SCI) who developed severe autonomic dysreflexia (AD) when a catheter rinse was carried out using a particular solution. Each of the cases developed immediate and, in some cases, intractable AD requiring further intervention to resolve symptoms. DISCUSSION: Catheter-associated urinary tract infection is a significant cause of morbidity and mortality in people living with SCI. Long-term catheters provide a vector for opportunistic micro-organisms to form bio-film and create an environment that promotes formation of struvite calculi, thus increasing the risk of chronic catheter blockage and urinary tract infection. Whilst these solutions are used to reduce these risks, they also pose additional risks to people susceptible to AD. These cases highlight the need for judicious patient selection and clinical oversight and management of adverse events when using catheter rinse solutions in certain people living with SCI. This is supported by a decision-making algorithm and a response to AD algorithm. This case report was prepared following the CARE Guidelines (supplementary file 1).

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.

Autonomic dysreflexia in urological practice: pathophysiology, prevention and treatment considerations.

PURPOSE: Spinal cord injury (SCI) leads to sensorimotor impairments; however, it can also be complicated by significant autonomic dysfunction, including cardiovascular and lower urinary tract (LUT) dysfunctions. Autonomic dysreflexia (AD) is a dangerous cardiovascular complication of SCI often overlooked by healthcare professionals. AD is characterized by a sudden increase in blood pressure (BP) that can result in severe cardiovascular and cerebrovascular complications. In this review, we provide an overview on the clinical manifestations, risk factors, underlying mechanisms, and current approaches in prevention and management of AD. METHODS: After conducting a literature research, we summarized relevant information regarding the clinical and pathophysiological aspects in the context of urological clinical practice CONCLUSIONS: The most common triggers of AD are those arising from LUT, such as bladder distention and urinary tract infections. Furthermore, AD is commonly observed in individuals with SCI during urological procedures, including catheterization, cystoscopy and urodynamics. Although significant progress in the clinical assessment of AD has been made in recent decades, effective approaches for its prevention and treatment are currently lacking.

Transcutaneous spinal cord stimulation and its impact on cardiovascular autonomic regulation after spinal cord injury.

Individuals with spinal cord injury (SCI) have significant dysfunction in cardiovascular autonomic regulation. Although recent findings postulate that spinal cord stimulation improves autonomic regulation, limited scope of past methods have tested only above level sympathetic activation, leaving significant uncertainty. To identify whether transcutaneous spinal cord stimulation improves cardiovascular autonomic regulation, two pairs of well-matched individuals with and without high thoracic, complete SCI were recruited. Baseline autonomic regulation was characterized with multiple tests of sympathoinhibition and above/below injury level sympathoexcitation. At three subsequent visits, testing was repeated with the addition submotor threshold transcutaneous spinal cord stimulation at three previously advocated frequencies. Uninjured controls demonstrated no autonomic deficits at baseline and had no changes with any frequency of stimulation. As expected, individuals with SCI had baseline autonomic dysfunction. In a frequency-dependent manner, spinal cord stimulation enhanced sympathoexcitatory responses, normalizing previously impaired Valsalva's maneuvers. However, stimulation exacerbated already impaired sympathoinhibitory responses, resulting in significantly greater mean arterial pressure increases with the same phenylephrine doses compared with baseline. Impaired sympathoexcitatory response below the level of injury were also further exacerbated with spinal cord stimulation. At baseline, neither individual with SCI demonstrated autonomic dysreflexia with the noxious foot cold pressor test; the addition of stimulation led to a dysreflexic response in every trial, with greater relative hypertension and bradycardia indicating no improvement in cardiovascular autonomic regulation. Collectively, transcutaneous spinal cord stimulation demonstrates no improvements in autonomic regulation after SCI, and instead likely generates tonic sympathoexcitation which may lower the threshold for dangerous autonomic dysreflexia.NEW & NOTEWORTHY Spinal cord stimulation increases blood pressure after spinal cord injury, though it is unclear if this restores natural autonomic regulation or induces a potentially dangerous pathological reflex. We performed comprehensive autonomic testing batteries, with and without transcutaneous spinal cord stimulation at multiple frequencies. Across 96 independent tests, stimulation did not change uninjured control responses, though all frequencies facilitated pathological reflexes without improved autonomic regulation for those with spinal cord injuries.

Autonomic dysreflexia: Current pharmacologic management.

BACKGROUND: Autonomic dysreflexia (AD) is a frequent complication of spinal cord injury (SCI), though current clinical practice patterns for medication management of this condition are unknown. Correspondingly, it is unclear if national differences in practice patterns exist. OBJECTIVE: To determine trends in current pharmacologic management of AD throughout the Americas. DESIGN: International survey of current physician practice patterns. SETTING: Academic medical center. PARTICIPANTS: Sixty physicians managing patients with SCI and prescribing medications to manage AD. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Presence of a formal pharmacologic AD management protocol, first- and second-line medications, patient characteristics influencing pharmacologic management. RESULTS: The majority of physicians (69%) had a formal AD management protocol for inpatient care, with nitroglycerin ointment (82%) being the most common first-line medication. Strong national differences existed regarding the use of nitroglycerin ointment, with 98% of U.S.-based physicians using this as first-line medication and 0% of physicians in Canada or Latin America using this due to recent lack of medication availability. Only 67% of physicians had a preferred second-line medication, with preferences split between hydralazine (48%) and nifedipine (28%). A systolic blood pressure threshold for pharmacologic management was used by 56% of physicians, wheres 26% considered neurological level of injury in decisions to use medications for AD. Heart rate was used by only 5% of physicians in their decision to manage AD with medications. CONCLUSIONS: As of 2023, U.S.-based physicians caring for individuals with SCI largely have formal inpatient protocols in place for medication management of AD, with nearly all relying on nitroglycerin ointment as their first-line medication. In areas outside of the United States where nitroglycerin ointment is unavailable, pharmacologic practice patterns significantly differ.

Effect of GR205171 on autonomic dysreflexia induced by colorectal distension in spinal cord injured rats.

STUDY DESIGN: Preclinical pharmacology. OBJECTIVES: To determine whether blocking substance P signaling attenuates the hypertension and bradycardia evoked by colorectal distension (CRD) in spinal cord injured (SCI) rats. SETTING: University laboratory in Pennsylvania, U.S.A. METHODS: Tachykinin NK1 receptor antagonists were administered 30 min prior to CRD three weeks after complete spinal cord transection at the 4th thoracic (T4) level. The dose range, route of administration, and pretreatment time was based on published data demonstrating occupancy of brain NK1 receptors in rodents. RESULTS: Subcutaneous (SC) administration of 10-30 mg/kg GR205171 ((2S,3S)-N-[[2-methoxy-5-[5-(trifluoromethyl)tetrazol-1-yl]phenyl]methyl]-2-phenylpiperidin-3-amine dihydrochloride) reduced CRD-induced hypertension and bradycardia by 55 and 49%, respectively, compared with pretreatment values. There was no effect of GR205171 on resting blood pressure or heart rate. In contrast, the same dose range of CP-99,994 ((2S,3S)-N-[(2-methoxyphenyl)methyl]-2-phenyl-3-piperidinamine dihydrochloride) had no effect on CRD-induced cardiovascular responses. CONCLUSIONS: The effective dose range of GR205171 to alleviate autonomic dysreflexia is consistent with the blockade of NK1 receptors on pelvic sensory afferents in the lumbosacral spinal cord, which may in turn prevent the over-excitation of sympathetic preganglionic neurons (SPNs) that regulate blood pressure and heart rate. The findings provide preclinical support for the utility of NK1 receptor antagonists to treat autonomic dysreflexia in people with SCI. The difference in the effects of the two NK1 receptor antagonists may reflect the ~200-fold lower affinity of CP-99,994 than GR205171 for the rat NK1 receptor.

[Efficacy of fesoterodine for prevention of autonomic dysreflexia in patients with neurogenic dysfunction of the bladder after spinal cord injury].

AIM: to evaluate the effectiveness of fesoterodine for the prevention of autonomic dysreflexia (AD) in patients with neurogenic bladder dysfunction (NBD) after spinal cord injury (SCI). MATERIALS AND METHODS: a total of 53 patients with AD were included in the study. In the main group (n=33) patients received fesoterodine 4 mg per day for 12 weeks as a treatment for neurogenic bladder dysfunction and prevention of AD. In the control group (n=20), patients were monitored for 12 weeks without specific treatment. The assessment was based on the results of ADFSCI and NBSS questionnaires, daily blood pressure monitoring with the completion of a self-observation diary, cystometry with simultaneous monitoring of blood pressure and heart rate. RESULTS: In the main group there was a significant decrease in episodes and severity of AD according to ADFSCI questionnaire and an improvement in the quality of life according to NBSS questionnaire compared to the control group (p<0.001). Also, in the main group, the number of episodes of AD and systolic blood pressure decreased. The maximum bladder capacity and bladder compliance increased (p<0.001), and the maximum detrusor pressure and systolic blood pressure when the cystometric capacity was reached, decreased significantly (p<0.001) in the main group compared in comparison with the control group. CONCLUSION: Fesoterodine at a dosage of 4 mg for 12 weeks reduced the severity of symptoms of AD in patients with SCI and NBD, which was manifested by the stabilization of blood pressure and a decrease in the number of episodes of AD, which significantly improved the quality of life. Also, the drug led to a significant improvement in urodynamic parameters during cystometry, in the form of a decrease in detrusor pressure and an increase in cystometric capacity. We can conclude that fesoterodine is effective in the prevention of AD in patients with NBD after SCI.

Clinical trial of home blood pressure monitoring following midodrine administration in hypotensive individuals with spinal cord injury.

BACKGROUND: Individuals with spinal cord injury (SCI) above thoracic level-6 (T6) experience impaired descending cortical control of the autonomic nervous system which predisposes them to blood pressure (BP) instability, including includes hypotension, orthostatic hypotension (OH), and autonomic dysreflexia (AD). However, many individuals do not report symptoms of these BP disorders, and because there are few treatment options that have been proven safe and effective for use in the SCI population, most individuals remain untreated. OBJECTIVE: The primary aim of this investigation was to determine the effects of midodrine (10 mg) prescribed TID or BID in the home environment, compared to placebo, on 30-day BP, study withdrawals, and symptom reporting associated with OH and AD in hypotensive individuals with SCI. DESIGN/METHODS: Participants were randomly assigned to received midodrine/placebo or placebo/midodrine, with a 2-weeks washout period in between, and both the participants and investigators were blinded to randomization order. Study medication was taken 2 or 3 times/day, depending on their sleep/wake schedule, BP, and any related symptoms were recorded before and 1 h after each dosage and periodically throughout the day. RESULTS: Nineteen individuals with SCI were recruited; however, 9 withdrew prior to completion of the full protocol. A total of 1892 BP recordings (75 ± 48 recordings/participant/30-day period) were collected in the 19 participants over the two 30-day monitoring periods. Average 30-day systolic BP was significantly increased with midodrine compared to placebo (114 ± 14 vs. 96 ± 11 mmHg, respectively; P = 0.004), and midodrine significantly reduced the number of hypotensive BP recordings compared to placebo (38.7 ± 41.9 vs. 73.3 ± 40.6, respectively; P = 0.01). However, compared to placebo, midodrine increased fluctuations in BP, did not improve symptoms of OH, but did significantly worsen the intensity of symptoms associated with AD (P = 0.03). CONCLUSION: Midodrine (10 mg) administered in the home environment effectively increases BP and reduces the incidence of hypotension; however these beneficial effects come at the expense of worsened BP instability and AD symptom intensity.

Anaesthetic management of tetraplegic pregnant patients during child delivery: A systematic review.

BACKGROUND: Pregnancy in spinal cord injured patients has specific issues that must be carefully addressed. However, guidelines for their management are scarce. METHODS: A systematic review of the literature regarding the anaesthetic management during delivery of pregnant patients with cervical spinal cord injury was performed on the electronic databases of PubMed (Medline) and Cochrane. RESULTS: Twenty-two papers were included. A higher incidence of preterm birth and caesarean delivery were seen. Anaesthetic management was diverse, although most pregnant patients received epidural analgesia. Autonomic dysreflexia symptoms were present in 51% of pregnancies. CONCLUSION: Timely management of these patients could possibly reduce caesarean and preterm delivery rates, avoid or minimize common complications, as well as reduce costs. An early reference to anaesthesiology consultation and a multidisciplinary approach is recommended.

Are local analgesics effective in reducing autonomic dysreflexia in individuals with spinal cord injury? A systematic review.

STUDY DESIGN: Systematic review. OBJECTIVES: To systematically review the evidence on the use of local analgesics, specifically lidocaine or bupivacaine, to prevent autonomic dysreflexia (AD) during iatrogenic procedures or bowel and bladder care routines in individuals with spinal cord injury (SCI). METHODS: A keyword search of MEDLINE, CINAHL, CENTRAL, Cochrane Reviews, PsycInfo, Embase, and Web of Science databases identified all English-language studies evaluating the efficacy of local analgesics in reducing AD. Included studies were either randomized controlled trials (RCTs) or quasi-experimental studies. Participants were adults with chronic SCI who received local analgesics prior to AD-triggering procedures or routines. Additionally, studies were required to report blood pressure values as an outcome. The methodology of this review followed the PRISMA checklist and was registered with PROSPERO (CRD42021219506). RESULTS: Four RCTs and two quasi-experimental studies met inclusion criteria. Results were narratively synthesized as meta-analysis was not possible due to heterogeneity across studies included in the review. All six studies administered lidocaine. Lidocaine was found to have a beneficial effect on AD in three studies, no effect in two studies and a detrimental effect in one study. CONCLUSIONS: Presently, RCTs and quasi-experimental studies on the use of lidocaine for reducing AD in individuals with SCI had small sample sizes and opposing findings. There is a strong need for definitive, well-monitored clinical trials with adequate sample sizes. Presently there is not enough compelling evidence to support or refute recommendations for the use of lidocaine from the AD management clinical practice guidelines.

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.

Fesoterodine Ameliorates Autonomic Dysreflexia While Improving Lower Urinary Tract Function and Urinary Incontinence-Related Quality of Life in Individuals With Spinal Cord Injury: A Prospective Phase IIa Study.

The aim of this prospective phase IIa, open-label exploratory, pre-post study was to determine the efficacy of fesoterodine (i.e., 12-week treatment period) to ameliorate autonomic dysreflexia (AD) in individuals with chronic SCI (> 1-year post-injury) at or above the sixth thoracic spinal segment, with confirmed history of AD and neurogenic detrusor overactivity (NDO). Twelve participants (four females, eight males; median age 42 years) completed this study and underwent urodynamics, 24-h ambulatory blood pressure monitoring (ABPM), and urinary incontinence-related quality of life (QoL) measures at baseline and on-treatment. The Montreal Cognitive Assessment (MoCA) and Neurogenic Bowel Dysfunction (NBD) score were used to monitor cognitive and bowel function, respectively. Compared with baseline, fesoterodine improved lower urinary tract (LUT) function, that is, increased cystometric capacity (205 vs. 475 mL, p = 0.002) and decreased maximum detrusor pressure (44 vs. 12 cm H2O, p = 0.009). NDO was eliminated in seven (58%) participants. Severity of AD events during urodynamics (40 vs. 27 mm Hg, p = 0.08) and 24-h ABPM (59 vs. 36 mm Hg, p = 0.05) were both reduced, yielding a large effect size (r = -0.58). AD Frequency (14 vs. 3, p = 0.004) during 24-h ABPM was significantly reduced. Urinary incontinence-related QoL improved (68 vs. 82, p = 0.02), however, cognitive (p = 0.2) and bowel function (p = 0.4) did not change significantly. In conclusion, fesoterodine reduces the magnitude and frequency of AD, while improving LUT function and urinary incontinence-related QoL in individuals with chronic SCI without negatively affecting cognitive or bowel function.

Rectal Application of Lidocaine Reduces the Severity of Autonomic Dysreflexia following Experimental Spinal Cord Injury.

Spinal cord injury (SCI) results in devastating cardiovascular dysfunction. Noxious stimuli from the rectum during bowel routine often trigger life-threatening blood pressure surges, termed autonomic dysreflexia (AD). Rectal application of anesthetic lidocaine jelly has been recommended during bowel care to reduce AD severity by mitigating sensory input. However, clinical studies have reported contradicting evidence. We performed a pre-clinical study on the efficacy of rectal lidocaine in a standardized rodent T3 transection model. We found that 2% and 10% lidocaine significantly reduced AD severity by 32% and 50%, respectively, compared with control (p < 0.0001). Our pre-clinical experiments support the current recommendation of rectal lidocaine application during bowel care.

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 ß1-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.

Heart rate changes associated with autonomic dysreflexia in daily life of individuals with chronic spinal cord injury.

STUDY DESIGN: Secondary data analysis. OBJECTIVE: To characterize heart rate (HR) changes during autonomic dysreflexia (AD) in daily life for individuals with chronic spinal cord injury (SCI). SETTING: University-based laboratory/community-based outpatient. METHODS: Cardiovascular data, previously collected during a 24-h ambulatory surveillance period in individuals with chronic SCI, were assessed. Any systolic blood pressure (SBP) increase ≥20 mmHg from baseline was identified and categorized into confirmed AD (i.e., diarized trigger), unknown (i.e., no diary entry), or unlikely AD (i.e., potential exertion driven SBP increase) groups. SBP-associated HR changes were categorized as unchanged, increased or decreased compared to baseline. RESULTS: Forty-five individuals [8 females, median age and time since injury of 43 years (lower and upper quartiles 36-50) and 17 years (6-23), respectively], were included for analysis. Overall, 797 episodes of SBP increase above AD threshold were identified and classified as confirmed (n = 250, 31.4%), unknown (n = 472, 59.2%) or unlikely (n = 75, 9.4%). The median number of episodes per individual within the 24-h period was 13 (8-28). HR-decrease/increase ratio was 3:1 for confirmed and unknown, and 1.5:1 for unlikely episodes. HR changes resulting in brady-/tachycardia were 34.4%/2.8% for confirmed, 39.6%/3.4% unknown, and 26.7%/9.3% for unlikely episodes, respectively. CONCLUSIONS: Our findings suggest that the majority of confirmed AD episodes are associated with a HR decrease. Using wearable-sensors-derived measures of physical activity in future studies could provide a more detailed characterization of HR changes during AD and improve AD identification.

Thoracic VGluT2+ Spinal Interneurons Regulate Structural and Functional Plasticity of Sympathetic Networks after High-Level Spinal Cord Injury.

Traumatic spinal cord injury (SCI) above the major spinal sympathetic outflow (T6 level) disinhibits sympathetic neurons from supraspinal control, causing systems-wide "dysautonomia." We recently showed that remarkable structural remodeling and plasticity occurs within spinal sympathetic circuitry, creating abnormal sympathetic reflexes that exacerbate dysautonomia over time. As an example, thoracic VGluT2+ spinal interneurons (SpINs) become structurally and functionally integrated with neurons that comprise the spinal-splenic sympathetic network and immunological dysfunction becomes progressively worse after SCI. To test whether the onset and progression of SCI-induced sympathetic plasticity is neuron activity dependent, we selectively inhibited (or excited) thoracic VGluT2+ interneurons using chemogenetics. New data show that silencing VGluT2+ interneurons in female and male mice with a T3 SCI, using hM4Di designer receptors exclusively activated by designer drugs (Gi DREADDs), blocks structural plasticity and the development of dysautonomia. Specifically, silencing VGluT2+ interneurons prevents the structural remodeling of spinal sympathetic networks that project to lymphoid and endocrine organs, reduces the frequency of spontaneous autonomic dysreflexia (AD), and reduces the severity of experimentally induced AD. Features of SCI-induced structural plasticity can be recapitulated in the intact spinal cord by activating excitatory hM3Dq-DREADDs in VGluT2+ interneurons. Collectively, these data implicate VGluT2+ excitatory SpINs in the onset and propagation of SCI-induced structural plasticity and dysautonomia, and reveal the potential for neuromodulation to block or reduce dysautonomia after severe high-level SCI.SIGNIFICANCE STATEMENT In response to stress or dangerous stimuli, autonomic spinal neurons coordinate a "fight or flight" response marked by increased cardiac output and release of stress hormones. After a spinal cord injury (SCI), normally harmless stimuli like bladder filling can result in a "false" fight or flight response, causing pathological changes throughout the body. We show that progressive hypertension and immune suppression develop after SCI because thoracic excitatory VGluT2+ spinal interneurons (SpINs) provoke structural remodeling in autonomic networks within below-lesion spinal levels. These pathological changes can be prevented in SCI mice or phenocopied in uninjured mice using chemogenetics to selectively manipulate activity in VGluT2+ SpINs. Targeted neuromodulation of SpINs could prevent structural plasticity and subsequent autonomic dysfunction in people with SCI.

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.