Non-pharmacological management of orthostatic hypotension after spinal cord injury: a critical review of the literature

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.

Effectiveness of non-pharmacological interventions to treat orthostatic hypotension in elderly people and people with a neurological condition: a systematic review

OBJECTIVE

The objective of this review was to summarize the best available evidence regarding the effectiveness of non-pharmacological interventions to treat orthostatic hypotension (OH) in elderly people and people with a neurological condition.

INTRODUCTION

Orthostatic hypotension is common in elderly people and people with a neurological condition and can interfere with or limit rehabilitation. Non-pharmacological interventions to treat OH could allow for longer and earlier mobilization, which is recommended in national clinical guidelines for rehabilitation in the acute or sub-acute phase following stroke or other neurological conditions.

INCLUSION CRITERIA

The review considered people aged 50 years and older, and people aged 18 years and elderly people with a neurological condition. Non-pharmacological interventions to treat OH included compression garments, neuromuscular stimulation, physical counter-maneuvers, aerobic or resistance exercises, sleeping with head tilted up, increasing fluid and salt intake, and timing and size of meals. The comparator was usual care, no intervention, pharmacological interventions, or other non-pharmacological interventions. Outcome measures included systolic blood pressure, diastolic blood pressure, heart rate, cerebral blood flow, observed/perceived symptoms, duration of standing or sitting in minutes, tolerance of therapy, functional ability, and adverse events/effects.

METHODS

Databases for published and unpublished studies available in English up to April 2018 with no lower date limit were searched. Critical appraisal was conducted using standardized instruments from JBI. Data were extracted using standardized tools designed for quantitative studies. Where appropriate, studies were included in a meta-analysis; otherwise, data were presented in a narrative form due to heterogeneity.

RESULTS

Forty-three studies - a combination of randomized controlled trials (n = 13), quasi-experimental studies (n = 28), a case control study (n = 1), and a case report (n = 1) - with 1069 participants were included. Meta-analyses of three interventions (resistance exercise, electrical stimulation, and lower limb compression bandaging) showed no significant effect of these interventions. Results from individual studies indicated physical maneuvers such as leg crossing, leg muscle pumping/contractions, and bending forward improved orthostatic hypotension. Abdominal compression improved OH. Sleeping with head up in combination with pharmacological treatment was more effective than sleeping with head up alone. Eating smaller, more frequent meals was effective. Drinking 480 mL of water increased blood pressure.

CONCLUSIONS

The review found mixed results for the effectiveness of non-pharmacological interventions to treat OH in people aged 50 years and older, and people with a neurological condition. There are several non-pharmacological interventions that may be effective in treating OH, but not all have resulted in clinically meaningful changes in outcome. Some may not be suitable for people with moderate to severe disability; therefore, it is important for clinicians to consider the patient's abilities and impairments when considering which non-pharmacological interventions to implement.

Haemodynamic and cerebrovascular effects of intermittent lower-leg compression as countermeasure to orthostatic stress

NEW FINDINGS

What is the central question of this study? Does smartly timed intermittent compression of the lower legs alter cerebral blood velocity and oxygenation during acute orthostatic challenges? What is the main finding and its importance? Intermittent compression timed to the local diastolic phase increased the blood flux through the legs and heart after two different orthostatic stress tests. Cerebral blood velocity improved during the first minute of recovery, and indices of cerebral tissue oxygenation remained elevated for 2 min. These results provide promise for the use of lower-leg active compression as a therapeutic tool for individuals vulnerable to initial orthostatic hypotension and orthostatic stress.

ABSTRACT

Intermittent compression of the lower legs provides the possibility of improving orthostatic tolerance by actively promoting venous return and improving central haemodynamics. We tested the hypothesis that intermittent compression of 65 mmHg timed to occur only within the local diastolic phase of each cardiac cycle would attenuate the decrease in blood pressure and improve cerebral haemodynamics during the first minute of recovery from two different orthostatic stress tests. Fourteen subjects (seven female) performed four squat-to-stand transitions and four repeats of standing bilateral thigh-cuff occlusion and release (TCR), with intermittent compression of the lower legs applied in half of the trials. Blood flow in the superficial femoral artery, mean arterial pressure, Doppler ultrasound cardiac output, total peripheral resistance, middle cerebral artery blood velocity (MCAv) and cerebral tissue saturation index (TSI%) were monitored. With both orthostatic stress tests, there was a significant compression × time interaction for superficial femoral artery flow (P < 0.001). The hypotensive state was attenuated with intermittent compression despite decreased total peripheral resistance (squat-to-stand, compression × time interaction, P < 0.001; TCR, compression × time interaction, P = 0.002) as a consequence of elevated cardiac output in both tests (P < 0.001). Intermittent compression also increased MCAv (P = 0.001) and TSI% (P < 0.001) during the squat-to-stand transition and during TCR (MCAv and TSI%, compression × time interaction, P < 0.001). Intermittent compression of the lower legs during quiet standing after an active orthostatic challenge augmented local, central and cerebral haemodynamics, providing potential as a therapeutic tool for individuals vulnerable to orthostatic stress.

Evidence-based position paper on Physical and Rehabilitation Medicine (PRM) professional practice for persons with spinal cord injury. The European PRM position (UEMS PRM Section)

INTRODUCTION

Spinal cord injury (SCI) is a devastating condition and a challenge for every health system and every society. This EBPP represents the official position of the European Union through the UEMS PRM Section and designates the professional role of PRM physicians for people with SCI. The aim of the paper was to improve Physical and Rehabilitation Medicine (PRM) physicians' professional practice for persons with SCI in order to improve their functionality, social and community reintegration, and to overcome activity limitations and/or participation restrictions.

EVIDENCE ACQUISITION

A systematic review of the literature and a consensus procedure by means of a Delphi process have been performed involving the delegates of all European countries represented in the UEMS PRM Section.

EVIDENCE SYNTHESIS

The systematic literature review is reported together with thirty-eight recommendations resulting from the Delphi procedure.

CONCLUSIONS

The professional role of PRM physicians who have expertise in the rehabilitation of SCI is to run rehabilitation programmes in multi-professional teams, working in an interdisciplinary way in a variety of settings to improve the functioning of people with SCI.

Epidural Spinal Cord Stimulation of Lumbosacral Networks Modulates Arterial Blood Pressure in Individuals With Spinal Cord Injury-Induced Cardiovascular Deficits

Disruption of motor and autonomic pathways induced by spinal cord injury (SCI) often leads to persistent low arterial blood pressure and orthostatic intolerance. Spinal cord epidural stimulation (scES) has been shown to enable independent standing and voluntary movement in individuals with clinically motor complete SCI. In this study, we addressed whether scES configured to activate motor lumbosacral networks can also modulate arterial blood pressure by assessing continuous, beat-by-beat blood pressure and lower extremity electromyography during supine and standing in seven individuals with C5-T4 SCI. In three research participants with arterial hypotension, orthostatic intolerance, and low levels of circulating catecholamines (group 1), scES applied while supine and standing resulted in increased arterial blood pressure. In four research participants without evidence of arterial hypotension or orthostatic intolerance and normative circulating catecholamines (group 2), scES did not induce significant increases in arterial blood pressure. During scES, there were no significant differences in electromyographic (EMG) activity between group 1 and group 2. In group 1, during standing assisted by scES, blood pressure was maintained at 119/72 ± 7/14 mmHg (mean ± SD) compared with 70/45 ± 5/7 mmHg without scES. In group 2 there were no arterial blood pressure changes during standing with or without scES. These findings demonstrate that scES configured to facilitate motor function can acutely increase arterial blood pressure in individuals with SCI-induced cardiovascular deficits.

Effects of Respiratory Training on Heart Rate Variability and Baroreflex Sensitivity in Individuals With Chronic Spinal Cord Injury

OBJECTIVE

To evaluate the effects of pressure threshold respiratory training (RT) on heart rate variability and baroreflex sensitivity in persons with chronic spinal cord injury (SCI).

DESIGN

Before-after intervention case-controlled clinical study.

SETTING

SCI research center and outpatient rehabilitation unit.

PARTICIPANTS

Participants (N=44) consisted of persons with chronic SCI ranging from C2 to T11 who participated in RT (n=24), and untrained control subjects with chronic SCI ranging from C2 to T9 (n=20).

INTERVENTIONS

A total of 21±2 RT sessions performed 5 days a week during a 4-week period using a combination of pressure threshold inspiratory and expiratory devices.

MAIN OUTCOME MEASURES

Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁), and beat-to-beat arterial blood pressure and heart rate changes during the 5-second-long maximum expiratory pressure maneuver (5s MEP) and the sit-up orthostatic stress test, acquired before and after the RT program.

RESULTS

In contrast to the untrained controls, individuals in the RT group experienced significantly increased FVC and FEV₁ (both P<.01) in association with improved quality of sleep, cough, and speech. Sympathetically (phase II) and parasympathetically (phase IV) mediated baroreflex sensitivity both significantly (P<.05) increased during the 5s MEP. During the orthostatic stress test, improved autonomic control over heart rate was associated with significantly increased sympathetic and parasympathetic modulation (low- and high-frequency change: P<.01 and P<.05, respectively).

CONCLUSIONS

Inspiratory-expiratory pressure threshold RT is a promising technique to positively affect both respiratory and cardiovascular dysregulation observed in persons with chronic SCI.

Clinical treatment of orthostatic hypotension after spinal cord injury with training based on electric uprise bed coupled with remote ECG and BP monitor

BACKGROUND

The treatment for orthostatic hypotension (OH) after spinal cord injury (SCI) is an important part of rehabilitation in late-stage SCI. Electric uprise bed training is a relatively commonly used method in treating OH, and how to carry out uprise bed training safely and effectively is an urgent problem. In the early stage of SCI, we used a remote monitoring system to monitor the whole process of uprise bed training, and we explored a safe and efficient method of electric uprise bed training.

MATERIAL AND METHODS

The experimental group consisted of 36 patients diagnosed with orthostatic hypotension (OH) after SCI and who received training with an electric uprise bed coupled with remote monitoring system, and the control group of 18 subjects who used a traditional training method.

RESULTS

There were no differences in baseline data between the 2 groups. There were no severe symptoms during training in the experimental group, but 3 patients had severe symptoms in the control group. Among the 32 enrolled subjects reaching upright training status within 30 days (17 subjects in the experimental group and 15 subjects in the control group), time interval of training from horizontal position to erect position in the experimental group was 18.00±3.12 days and 21.40±4.95 days in the control group. Time interval in the experimental group was significantly less than in the control group. However, among all 36 subjects, by combining results of follow-up, there was no significant difference of time interval of training from horizontal position to erect position between the experimental group and the control group. In the experimental group 90.52% of patients finished training compared to 78.19% in the control group (P<0.01). After training, values of OCs and OCd of the experimental group were lower than in the control group. There was no significant difference between groups in number of re-diagnosed OH.

CONCLUSIONS

Implementation of training with electric uprise bed coupled with remote monitoring system is generally safe for patients with OH after SCI. For patients who could reach standing training status within 30 days, implementation can improve efficiency of training by shortening time interval of training from horizontal position to erect position. It can increase orthostatic blood pressure change during position change.

A systematic review of the management of orthostatic hypotension after spinal cord injury

OBJECTIVE

To review systematically the evidence for the management of orthostatic hypotension (OH) in patients with spinal cord injuries (SCIs).

DATA SOURCES

A key word literature search was conducted of original and review articles as well as practice guidelines using Medline, CINAHL, EMBASE, and PsycInfo, and manual searches of retrieved articles from 1950 to July 2008, to identify literature evaluating the effectiveness of currently used treatments for OH.

STUDY SELECTION

Included randomized controlled trials (RCTs), prospective cohort studies, case-control studies, pre-post studies, and case reports that assessed pharmacologic and nonpharmacologic intervention for the management of OH in patients with SCI.

DATA EXTRACTION

Two independent reviewers evaluated the quality of each study, using the Physiotherapy Evidence Database score for RCTs and the Downs and Black scale for all other studies. Study results were tabulated and levels of evidence assigned.

DATA SYNTHESIS

A total of 8 pharmacologic and 21 nonpharmacologic studies were identified that met the criteria. Of these 26 studies (some include both pharmacologic and nonpharmacologic interventions), only 1 pharmacologic RCT was identified (low-quality RCT producing level 2 evidence), in which midodrine was found to be effective in the management of OH after SCI. Functional electrical stimulation was one of the only nonpharmacologic interventions with some evidence (level 2) to support its utility.

CONCLUSIONS

Although a wide array of physical and pharmacologic measures are recommended for the management of OH in the general population, very few have been evaluated for use in SCI. Further research needs to quantify the efficacy of treatment for OH in subjects with SCI, especially of the many other pharmacologic interventions that have been shown to be effective in non-SCI conditions.

Abdominal binder use in people with spinal cord injuries: a systematic review and meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

To review the evidence for the use of an abdominal binder on breathing, speech and cardiovascular function in people who have suffered a spinal cord injury (SCI).

SETTING

Brisbane, Australia.

METHODS

A search of multiple databases (Medline, Cinahl, Cochrane, Embase, PEDro) was undertaken accompanied by the reference list evaluation of each relevant publication identified. Methodological quality of studies identified was assessed using the PEDro scale. The size of effect of an abdominal binder on outcomes was also calculated where sufficient data were reported. Further descriptive analysis was performed.

RESULTS

Eleven studies met the review inclusion criteria and employed either crossover or within subject designs. Comparison of studies involving elastic and non-elastic binders was performed. A PEDro mean score of 4.3 out of 8 (range: 3-6) was found. Meta-analysis indicated that the use of abdominal binders improved vital capacity (VC) by (weighted mean difference (95% confidence interval (CI)) 0.32 (0.09, 0.55) litres, decreased functional residual capacity (FRC) by 0.41 (0.14, 0.67) litres, but did not significantly influence total lung capacity (TLC).

CONCLUSIONS

This review found some evidence that the use of an abdominal binder improves VC, but decreases FRC when assuming the sitting or tilted position in people who have suffered SCI. Overall, the quality of the studies was poor. Available evidence is not yet sufficient to either support or discourage the use of an abdominal binder in this patient population. Further studies utilizing more methodologically rigorous designs are required.