Spinal cord stimulation for non-reconstructable chronic critical leg ischaemia

PROMISE international; a clinical post marketing trial investigating the percutaneous deep vein arterialization (LimFlow) in the treatment of no-option chronic limb ischemia patient

BACKGROUND

Critical limb ischemia (CLI) is the clinical end stage of peripheral artery disease and is associated with high amputation, mortality rates and poor quality of life. For CLI patients with no revascularization options, venous arterialization could be an alternative technique for limb salvage. A systematic review and meta-analysis published in 2017 concluded that venous arterialization may be considered a viable alternative. A recent development, is the Percutaneous Deep Vein Arterialization (pDVA), that is CE-marked and currently under investigation of the FDA. This procedure, called LimFlow, is a novel, minimally invasive, endovascular approach to perform a venous arterialization procedure. The limited evidence for its use necessitates a scientific judgement of the pDVA. Therefore, we initiated a prospective clinical post market trial to investigate the outcome of the pDVA in no-option critical limb ischemia.

METHODS/DESIGN

The objective of this prospective study is to collect "real-life" clinical data among a population of patients treated with the pDVA in order to evaluate the clinical effectiveness and safety of the LimFlow System in patients with no-option critical limb ischemia. This study is a single-arm, open-label, prospective, post-market follow-up study to be conducted on up to fifty (50) eligible patients with a twelve-month follow-up period. The Primary endpoint is measured by amputation free survival. Secondary endpoints are complete wound healing, primary and secondary patency, limb salvage, renal function and technical and procedural success. Patients will be assessed at regular intervals during one year after the initial percutaneous deep vein arterialization procedure through clinical evaluation and self-completed questionnaires.

DISCUSSION

The last decade several studies have been published with promising results and the number of treated patients has considerably grown. Venous arterialization could be a valuable treatment option in patients with often no other options than amputation of the affected limb. The first results in men are promising although more research and long term follow up is needed to establish the efficacy of this new treatment modality. With this prospective study, we evaluate the clinical effectiveness and safety in patients with no-option CLI treated with the pDVA (LimFlow System).

TRIAL REGISTRATION

NCT03321552 .

Surgical and endovascular venous arterialization for treatment of critical limb ischaemia

Patients with critical limb ischaemia have a poor life expectancy. Aggressive revascularization is accepted in order to preserve their independence in the final phase of their lives. Bypass surgery and more recently endovascular interventions with angioplasty and stenting have become the treatment of choice to prevent amputation and to resolve pain. However, as many as 20 % of patients with critical limb ischaemia are unsuitable candidates for a vascular intervention because of extensive occlusions of outflow in the crural and pedal vessels. Such "no-option critical limb ischaemia" may be treated with venous arterialization. In the present review, we discuss the history of the venous arterialization procedure, the mechanisms, the different techniques, and complications of venous arterialization.

Spinal cord stimulation for cancer-related pain in adults

BACKGROUND

This is an update of a review first published in The Cochrane Library in Issue 3, 2013. Cancer-related pain places a heavy burden on public health with related high expenditure. Severe pain is associated with a decreased quality of life in patients with cancer. A significant proportion of patients with cancer-related pain are under-treated. There is a need for more effective control of cancer-related pain. Spinal cord stimulation (SCS) may have a role in pain management. The effectiveness and safety of SCS for patients with cancer-related pain is currently unknown.

OBJECTIVES

This systematic review evaluated the effectiveness of SCS for cancer-related pain compared with standard care using conventional analgesic medication. We also appraised risk and potential adverse events associated with the use of SCS.

SEARCH METHODS

This is an update of a review first published in The Cochrane Library in Issue 3, 2013. The search strategy for the update was the same as in the original review. We searched the following bibliographic databases in order to identify relevant studies: the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library; MEDLINE; EMBASE; and CBM (Chinese Biomedical Database) in October 2014. We also handsearched relevant journals. There were no language restrictions.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) that directly compared SCS with other interventions with regards to the effectiveness of pain management. We also planned to include cross-over trials that compared SCS with another treatment. We planned to identify non-randomised controlled trials but these would only be included if no RCTs could be found.

DATA COLLECTION AND ANALYSIS

The literature search for the update of this review found 121 potentially eligible articles. The initial search strategy yielded 430 articles. By scrutinising titles and abstracts, we found 412 articles irrelevant to the analytical purpose of this systematic review due to different scopes of diseases or different methods of intervention (intrathecal infusion system; oral medication) or aims other than pain control (spinal cord function monitoring, bladder function restoration or amelioration of organ metabolism). The remaining 18 trials were reviewed as full manuscripts. No RCTs were identified. Fourteen sporadic case reports and review articles were excluded and four before-and-after case series studies (92 participants) were included. Two review authors independently selected the studies to be included in the review according to the prespecified eligibility criteria. A checklist for methodological quality of non-randomised controlled trials was used (STROBE checklist) and all review authors discussed and agreed on the inclusion of trials and the results of the quality assessment.

MAIN RESULTS

No new studies were identified for inclusion in this update of the review. Four before-and-after case series studies (a total of 92 participants) met our criteria for inclusion in the previous version of the review. All included trials adopted a visual analogue scale (VAS) to evaluate pain relief. Heterogeneity existed in terms of baseline characteristics, electrode and stimulator parameters, level of implantation and route of implantation; each trial reported data differently. In two trials, pain relief was achieved in 76% (48/63) of participants at the end of the follow-up period. In the third trial, pre-procedure VAS was 6 to 9 (mean 7.43 ); the one-month post-implant VAS was 2 to 4 (mean 3.07); the 12-month post-implant VAS was 1 to 3 (mean 2.67). In the fourth trial, the pre-procedure VAS was 6 to 9 (mean 7.07); 1 to 4 (mean 2.67) at one-month; 1 to 4 (mean 1.87) at 12 months. Analgesic use was largely reduced. The main adverse events were infection of sites of implantation, cerebrospinal fluid (CSF) leakage, pain at the sites of electrodes, dislodgement of the electrodes, and system failure; however, the incidence in participants with cancer could not be calculated. Since all trials were small, non-randomised controlled trials, they carried high or unclear risk of all types of bias.

AUTHORS' CONCLUSIONS

Since the first publication of this review, no new studies were identified. Current evidence is insufficient to establish the role of SCS in treating refractory cancer-related pain. Future randomised studies should focus on the implantation of SCS in participants with cancer-related pain.

Spinal cord stimulation for cancer-related pain in adults

BACKGROUND

Cancer-related pain places a heavy burden on public health with related high expenditure. Severe pain is associated with a decreased quality of life in patients with cancer. A significant proportion of patients with cancer-related pain are under-treated.There is a need for more effective control of cancer-related pain. Spinal cord stimulation (SCS) may have a role in pain management. The effectiveness and safety of SCS for patients with cancer-related pain is currently unknown.

OBJECTIVES

This systematic review evaluated the effectiveness of SCS for cancer-related pain compared with standard care using conventional analgesic medication. We also appraised risk and potential adverse events associated with the use of SCS.

SEARCH METHODS

We searched the following bibliographic databases in order to identify relevant studies: the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Libary (from inception to 2012, Issue 6); MEDLINE; EMBASE; and CBM (Chinese Biomedical Database) (from inception to July, 2012). We also handsearched relevant journals.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) that directly compared SCS with other interventions with regards to the effectiveness of pain management. We also planned to include cross-over trials that compared SCS with another treatment. We planned to identify non-randomised controlled trials but these would only be included if no RCTs could be found.

DATA COLLECTION AND ANALYSIS

The initial search strategy yielded 430 articles. By scrutinising titles and abstracts, we found 412 articles irrelevant to the analytical purpose of this systematic review due to different scopes of diseases or different methods of intervention (intrathecal infusion system; oral medication) or aims other than pain control (spinal cord function monitoring, bladder function restoration or amelioration of organ metabolism). The remaining 18 trials were reviewed as full manuscripts. No RCTs were identified. Fourteen sporadic case reports and review articles were excluded and four before-and-after case series studies (92 participants) were included. Two review authors independently selected the studies to be included in the review according to the pre-specified eligibility criteria. A checklist for methodological quality of non-randomised controlled trials was used (STROBE checklist) and all review authors discussed and agreed on the inclusion of trials and the results of the quality assessment.

MAIN RESULTS

Four before-and-after case series studies (a total of 92 participants) met our criteria for inclusion. All included trials adopted a visual analogue scale (VAS) to evaluate pain relief. Heterogeneity existed in terms of baseline characteristics, electrode and stimulator parameters, level of implantation and route of implantation; data reporting was different among all trials. In two trials, pain relief was achieved in 76% (48/63) of patients at the end of the follow-up period. In the third trial, pre-procedure VAS was 6 to 9 (mean 7.43 ); the one-month post-implant VAS was 2 to 4 (mean 3.07); the 12-month post-implant VAS was 1 to 3 (mean 2.67). In the fourth trial, the pre-procedure VAS was 6 to 9 (mean 7.07); 1 to 4 (mean 2.67) at one-month; 1 to 4 (mean 1.87) at 12 months. Analgesic use was largely reduced. The main adverse events were infection of sites of implantation, cerebrospinal fluid (CSF) leakage, pain at the sites of electrodes, dislodgement of the electrodes and system failure, however, the incidence in patients with cancer could not be calculated. Since all trials were non-randomised controlled trials, they carried risk of all types of bias.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to establish the role of SCS in treating refractory cancer-related pain. Future randomised studies should focus on the implantation of SCS in patients with cancer-related pain.

Spinal cord stimulation for non-reconstructable chronic critical leg ischaemia

BACKGROUND

Patients suffering from inoperable chronic critical leg ischaemia (NR-CCLI) face amputation of the leg. Spinal cord stimulation (SCS) has been proposed as a helpful treatment in addition to standard conservative treatment.

OBJECTIVES

To find evidence for an improvement on limb salvage, pain relief, and the clinical situation using SCS compared to conservative treatment alone.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched January 2013) and CENTRAL (2012, Issue 12).

SELECTION CRITERIA

Controlled studies comparing the addition of SCS with any form of conservative treatment to conservative treatment alone in patients with NR-CCLI.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed the quality of the studies and extracted data.

MAIN RESULTS

Six studies comprising nearly 450 patients were included. In general the quality of the studies was good. No study was blinded due to the type of intervention.Limb salvage after 12 months was significantly higher in the SCS group (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.56 to 0.90; risk difference (RD) -0.11, 95% CI -0.20 to -0.02). Significant pain relief occurred in both treatment groups, but was more prominent in the SCS group where the patients required significantly less analgesics. In the SCS group, significantly more patients reached Fontaine stage II than in the conservative group (RR 4.9, 95% CI 2.0 to 11.9; RD 0.33, 95% CI 0.19 to 0.47). Overall, no significantly different effect on ulcer healing was observed with the two treatments.Complications of SCS treatment consisted of implantation problems (9%, 95% CI 4 to 15%) and changes in stimulation requiring re-intervention (15%, 95% CI 10 to 20%). Infections of the lead or pulse generator pocket occurred less frequently (3%, 95% CI 0 to 6%). Overall risk of complications with additional SCS treatment was 17% (95% CI 12 to 22%), indicating a number needed to harm of 6 (95% CI 5 to 8).Average overall costs (one study) at two years were EUR 36,500 (SCS group) and EUR 28,600 (conservative group). The difference (EUR 7900) was significant (P < 0.009).

AUTHORS' CONCLUSIONS

There is evidence to favour SCS over standard conservative treatment alone to improve limb salvage and clinical situations in patients with NR-CCLI. The benefits of SCS must be considered against the possible harm of relatively mild complications and the costs.

Transcutaneous spinal direct current stimulation

In the past 10 years renewed interest has centered on non-invasive transcutaneous weak direct currents applied over the scalp to modulate cortical excitability ("brain polarization" or transcranial direct current stimulation, tDCS). Extensive literature shows that tDCS induces marked changes in cortical excitability that outlast stimulation. Aiming at developing a new, non-invasive, approach to spinal cord neuromodulation we assessed the after-effects of thoracic transcutaneous spinal DC stimulation (tsDCS) on somatosensory potentials (SEPs) evoked in healthy subjects by posterior tibial nerve (PTN) stimulation. Our findings showed that thoracic anodal tsDCS depresses the cervico-medullary PTN-SEP component (P30) without eliciting adverse effects. tsDCS also modulates post-activation H-reflex dynamics. Later works further confirmed that transcutaneous electric fields modulate spinal cord function. Subsequent studies in our laboratory showed that tsDCS modulates the flexion reflex in the human lower limb. Besides influencing the laser evoked potentials (LEPs), tsDCS increases pain tolerance in healthy subjects. Hence, though the underlying mechanisms remain speculative, tsDCS modulates activity in lemniscal, spinothalamic, and segmental motor systems. Here we review currently available experimental evidence that non-invasive spinal cord stimulation (SCS) influences spinal function in humans and argue that, by focally modulating spinal excitability, tsDCS could provide a novel therapeutic tool complementary to drugs and invasive SCS in managing various pathologic conditions, including pain.

Spinal cord stimulation in pain management: a review

Spinal cord stimulation has become a widely used and efficient alternative for the management of refractory chronic pain that is unresponsive to conservative therapies. Technological improvements have been considerable and the current neuromodulation devices are both extremely sophisticated and reliable in obtaining good results for various clinical situations of chronic pain, such as failed back surgery syndrome, complex regional pain syndrome, ischemic and coronary artery disease. This technique is likely to possess a savings in costs compared with alternative therapy strategies despite its high initial cost. Spinal cord stimulation continues to be a valuable tool in the treatment of chronic disabling pain.

Modification of loco-regional microenvironment in brain tumors by spinal cord stimulation. Implications for radio-chemotherapy

The effectiveness of radiotherapy and chemotherapy in high grade gliomas (HGG) depends on tumor micro-environment. We summarize our experience of the influence of spinal cord stimulation (SCS) on this micro-environment. Patients with HGG (n = 26) were assessed pre- and post-SCS, using: (1) Doppler in middle cerebral arteries (MCA) and (2) in common carotid arteries (CCA); (3) tumor blood-flow using single photon emission computed tomography (SPECT); (4) tumor-pO(2) (mmHg) using polarographic probes (eight tumor areas from five patients); and (5) tumor glucose metabolism using (18)F-fluoro-2-deoxyglucose ((18)FDG) positron emission tomography ((18)FDG-PET). Pre-SCS: tumor blood-flow was lower (P < 0.001) than peri-tumor areas and healthy contra-lateral areas. Tumor-pO(2) was lower (P < 0.042) than healthy tissue. Tumor glucose metabolism was higher than peri-tumor areas (P = 0.017) and healthy contra-lateral areas (P = 0.048). Post-SCS: there were increases in: MCA blood-flow (P ≤ 0.002), CCA blood-flow (P ≤ 0.013), tumor blood-flow (P = 0.033), tumor glucose metabolism (P = 0.027) and tumor-pO(2) (P = 0.022). The percentage of hypoxic values decreased (P = 0.007). SCS can modify tumor micro-environment. The potential usefulness of SCS in improving the effectiveness of radio-chemotherapy in HGG needs to be evaluated.

Spinal cord stimulation for patients with inoperable chronic critical leg ischemia

BACKGROUND

Because of the prevalence of diabetes, the treatment of diabetic foot is still challenging. Even an exactly proved effective and practical method can't be listed except vascular surgery which is not a long-term way for it. Spinal cord stimulation (SCS) is a very promising option in the treatment algorithm of inoperable chronic critical leg ischemia (CLI).

DATA SOURCES

We searched Pubmed database with key words or terms such as "spinal cord stimulation", "ischemic pain" and "limb ischemia" appeared in the last five years.

RESULTS

The mechanism of SCS is unclear. Two theories have emerged to interpret the benefits of SCS. Pain relief from SCS can be confirmed by a majority of the studies, while limb salvage and other more ambitious improvements have not come to an agreement. The complications of SCS are not fatal, but most of them are lead migration, lead connection failure, and local infection.

CONCLUSIONS

SCS is a safe, promising treatment for patients with inoperable CLI. It is effective in pain reduction compared with traditional medical treatment.

Foot venous system arterialization for salvage of nonreconstructable acute ischemic limb: a case report

Patients 73 years old man, was admitted to the Hospital with acute ischaemia of the left lower limb, pain started 4 days ago. Ultrasound investigation and lower limbs angiography were performed. Giant infrapopliteal aneurysm and thrombosis due to massive embolism of the crural and pedal arteries' was revealed. In order to keep the limb, urgent surgical treatment--popliteal aneurysm ligation and foot venous system arterialisation was performed. Urgent venous arterialisation may be considered as viable alternative in patients with limb acute ischaemia, when arterial reconstruction is impossible to perform. In our case improvement of the foot perfusion during 8 days increases the interest to this technique.

What is the evidence on efficacy of spinal cord stimulation in (subgroups of) patients with critical limb ischemia?

The use of spinal cord stimulation (SCS) has been advocated for the management of ischemic pain and the prevention of amputations in patients with inoperable critical limb ischemia (CLI), although data on benefit are conflicting. Several reports described apparently differential treatment effects in subgroups. The purpose of this study was to analyze the data on the efficacy of SCS and to clarify preselection issues. Five randomized trials have been performed with a total number of 332 patients. Primary outcome measures were mortality and limb survival. In the largest multicenter randomized trial (n = 120), which compared SCS treatment and best medical treatment alone in patients with inoperable CLI, we determined the incidence of amputation and its relation to various predefined risk factors. We used Kaplan-Meier and Cox regression analyses to quantify prognostic effects and differential treatment effects. Meta-analysis yielded a relative risk for amputation of 0.79 and a risk difference of -0.07 (p = 0.15). The risk factor analysis clearly showed that patients with ischemic skin lesions (ulcerations or gangrene) had a worse prognosis (i.e., higher risk of amputation) (relative risk 2.30, p = 0.01). We did not observe significant interactions between this prognostic factor (or any other) and the effect of SCS. The analysis did not indicate a subgroup of patients who might specifically be helped by SCS. Meta-analysis including all randomized data shows insufficient evidence for higher efficacy of SCS treatment compared with best medical treatment alone. Although some factors provide prognostic information as to the risk of amputation in patients with CLI, there are no data supporting a more favorable treatment effect in any group.

Immersing Feet in Carbon Dioxide-enriched Water Prevents Expansion and Formation of Ischemic Ulcers after Surgical Revascularization in Diabetic Patients with Critical Limb Ischemia

OBJECTIVE

We investigated the effect of immersion of feet in CO2-enriched water for preventing expansion and formation of ischemic ulcer in critical limb ischemia of diabetic patients after surgical revascularization.

MATERIALS AND METHODS

Eligible patients were allocated CO2 group (CO2 immersion plus standard care) or control group (standard care alone) and were followed up for 3 months after surgical revascularization. The end point is defined as an expansion of a target ulcer (more than 101% of original size) or the formation of new ulcers during the follow-up period.

RESULTS

Fifty-nine patients out of originally enrolled 66 patients with type II diabetes were included in intention-to-treat population. The cumulative prevention rate for ischemic ulcer after 3 months was 97.1% in the CO2 group, while, in the control group, it was 77.8%, i.e., significantly lower than the CO2 group (P = 0.012, log-rank test). The transcutaneous oxygen pressure increased significantly only in the CO2 group, from 56 ± 14 to 63 ± 15 mmHg (P < 0.01, Wilcoxon signed rank test), in 3 months.

CONCLUSION

These results suggest that addition of CO2 immersion to standard care of critical limb ischemia in diabetic patients improves early postoperative outcome after vascular surgery.

[Therapy of chronic ischemic pain in peripheral arterial disease. A survey among physicians]

BACKGROUND

The intention of this study was to determine the status quo of commonly used pain therapies amongst treating physicians of different specialties and to examine their view on the problem of chronic ischemic pain.

METHODS

A total of 281 physicians treating patients with chronic ischemic pain were surveyed. The surveyed physicians were mainly specialists in the fields of surgery, pain therapy, and internal medicine.

RESULTS

Mainly a pharmacological therapy (metamizol/paracetamol, weak and strong opioids) was used in the treatment of chronic ischemic pain. We found differences between the specialties, for instance pain specialists used antidepressants and anticonvulsants more often than others. Therapeutic options were also evaluated differently by surgeons, pain therapists, and internal specialists: 57% of the surgeons considered the available symptomatic treatment options as sufficient whereas only 21% of the pain specialists agreed with that opinion.

CONCLUSION

The differences among the specialties and the fact that the majority of physicians characterized the available symptomatic treatment options as insufficient point towards a need to review the treatment of ischemic pain in an interdisciplinary approach.

Spinal cord stimulation: an update

Spinal cord stimulation has been used in the treatment of many chronic pain disorders since 1967. In this update, the indications for spinal cord stimulation are reviewed with attention to recent publications. A focused review of the literature on abdominal and visceral pain syndromes is also provided. Furthermore, the technology has evolved from the use of monopolar electrodes to complex electrode arrays. Similarly, the power source has changed from a radio frequency-driven system to a rechargeable impulse generator. These topics are covered, along with a short discussion of implant technique. Finally, we include a review of complications of such therapy. SCS as a technology and therapy continues to evolve.

Current state and perspective on medical treatment of critical leg ischemia: gene and cell therapy

Critical limb ischemia (CLI) is a severe disease associated with a high risk of amputation and mortality. In patients who cannot be revascularized, several medical options have been tested, including the use of prostanoids, spinal cord stimulation, and lumbar sympathectomy. None of these treatments has demonstrated a benefit on the amputation rates after 6 months of follow-up; these treatments cannot therefore be recommended for CLI treatment in patients for whom surgery is not an option. In this setting, gene therapy and cell therapy to stimulate angiogenesis have been tested mainly in phase I and II clinical trials and are reviewed in this article. These studies demonstrated the short-term safety and feasibility of these new approaches, but larger randomized studies remain necessary to demonstrate their clinical benefits and longterm safety.