The effect of calf neuromuscular electrical stimulation and intermittent pneumatic compression on thigh microcirculation

Continuous muscle pump activation by neuromuscular electrical stimulation of the common peroneal nerve in the treatment of patients with venous leg ulcers: A position paper

The standard treatment for patients with confirmed Venous Leg Ulcers (VLUs) is compression therapy to improve the function of the calf muscle pump. There is a significant cohort of patients who are unable to tolerate optimal compression therapy or indeed any level of compression therapy. In addition, there is a cohort of patients who can tolerate compression whose ulcers show little or no evidence of healing. There is a need for ways to further improve calf muscle pump function and to improve venous ulcer healing in these patients. Published data were reviewed on the use of Muscle Pump Activation (MPA) using common peroneal nerve neuromuscular electrical stimulation (NMES) to improve calf muscle pump function. There is physiological evidence that MPA can improve calf muscle pump function and venous return in both control subjects and in patients with venous disease. The use of MPA has also been shown to improve venous flow volume and venous flow velocity on ultrasound scanning in patients with venous disease. MPA has been shown to improve microcirculation in the skin using Laser Doppler and laser Doppler Speckle Contrast Imaging, in both normal subjects as well as in patients with venous disease and VLU. A recent randomized controlled trial of MPA plus compression therapy compared with compression therapy alone, found significantly faster rates of healing with the use of MPA in addition to compression therapy. There are indications for the use of MPA as an adjunctive treatment to enhance calf muscle pump function in patients with VLU: who cannot tolerate compression therapy who can only tolerate suboptimal, low-level compression whose ulcer healing remains slow or stalled with optimal compression.

Efficiency of Direct Transcutaneous Electroneurostimulation of the Median Nerve in the Regression of Residual Neurological Symptoms after Carpal Tunnel Decompression Surgery

Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy. CTS therapy includes wrist immobilization, kinesiotherapy, non-steroidal anti-inflammatory drugs, carpal tunnel steroid injection, acupuncture, and physical therapy. Carpal tunnel decompression surgery (CTDS) is recommended after failure of conservative therapy. In many cases, neurological disorders continue despite CTDS. The aim of this study was to investigate the efficiency of direct transcutaneous electroneurostimulation (TENS) of the median nerve in the regression of residual neurological symptoms after CTDS. Material and Methods: 60 patients aged 28-62 years with persisting sensory and motor disorders after CTDS were studied; 15 patients received sham stimulation with a duration 30 min.; 15 patients received high-frequency low-amplitude TENS (HF TENS) with a duration 30 min; 15 patients received low-frequency high-amplitude TENS (LF TENS) with a duration 30 min; and 15 patients received a co-administration of HF TENS (with a duration of15 min) and LF TENS (with a duration of 15 min). Results: Our research showed that TENS significantly decreased the pain syndrome, sensory disorders, and motor deficits in the patients after CTDS. Predominantly, negative and positive sensory symptoms and the pain syndrome improved after the HF TENS course. Motor deficits, reduction of fine motor skill performance, electromyography changes, and affective responses to chronic pain syndrome regressed significantly after the LF TENS course. Co-administration of HF TENS and LF TENS was significantly more effective than use of sham stimulation, HF TENS, or LF TENS in patients with residual neurological symptoms after CTDS.

Real-time, multi-spectral motion artefact correction and compensation for laser speckle contrast imaging

Laser speckle contrast imaging (LSCI) is so sensitive to motion that it can measure the movement of red blood cells. However, this extreme sensitivity to motion is also its pitfall as the clinical translation of LSCI is slowed down due to the inability to deal with motion artefacts. In this paper we study the effectiveness of a real-time, multi-spectral motion artefact correction and compensation by subduing an in vitro flow phantom and ex vivo porcine kidney to computer-controlled motion artefacts. On the in vitro flow phantom, the optical flow showed a good correlation with the total movement. This model results in a better signal-to-noise ratios for multiple imaging distances and the overestimation of perfusion was reduced. In the ex vivo kidney model, the perfusion overestimation was also reduced and we were still able to distinguish between ischemia and non-ischemia in the stabilized data whereas this was not possible in the non-stabilized data. This leads to a notably better perfusion estimation that could open the door to a multitude of new clinical applications for LSCI.

Role of Neuromuscular Electrical Stimulation in Increasing Femoral Venous Blood Flow After Total Hip Prosthesis

Objective: This study aimed to investigate the role of neuromuscular electrical stimulation (NMES) in increasing femoral venous blood flow after total hip prosthesis and to evaluate its potential effects on preventing postoperative deep vein thrombosis (DVT).

Materials and methods: A total of 64 patients who underwent total hip prosthesis were randomly separated into two groups. The NMES group (n=32) received low-molecular-weight heparin+NMES. And the non-NMES group (n=32) received a low-molecular-weight heparin+compression bandage.

Results: There was no difference between the groups in terms of the presence of preoperative and postoperative leg edema. The calf diameter was significantly lower in the NMES group than in the non-NMES group in both the preoperative (p=0.003) and postoperative (p=0.008) period. Although the femoral vein peak velocity (VPV) was similar between the groups in the preoperative period, it was significantly higher in the NMES group than in the non-NMES group postoperatively (p=0.001). The femoral VPV after total hip prosthesis increased more in the NMES group (43.2%) compared with the non-NMES group (16.3%). In the non-NMES group, the D-dimer value in the preoperative period was lower than on postoperative days one and five (p<0.05). There was no significant difference between the D-dimer values on postoperative days one and five. In the NMES group, a statistically significant difference was determined between the preoperative and postoperative test results (F(2.93)=20.86, p=0.001). The preoperative D-dimer values were compared to the postoperative values on the first and fifth day, and according to the post hoc test results, the D-dimer values were significantly lower on the fifth postoperative day than on the first postoperative day, and the preoperative value was significantly lower than the fifth postoperative day value (p<0.05). 

Conclusion: Although the two groups were similar in terms of leg edema, there was a significant increase in femoral VPV in the NMES group. This could indicate a potential effect of NMES in preventing postoperative DVT and needs to be confirmed with further studies.

Neuromuscular electrical stimulation to augment lower limb exercise and mobility in individuals with spastic cerebral palsy: A scoping review

Background: Neuromuscular Electrical Stimulation (NMES) is an emerging assistive technology applied through surface or implanted electrodes to augment skeletal muscle contraction. NMES has the potential to improve function while reducing the neuromuscular impairments of spastic cerebral palsy (CP). This scoping review examines the application of NMES to augment lower extremity exercises for individuals with spastic CP and reports the effects of NMES on neuromuscular impairments and function in spastic CP, to provide a foundation of knowledge to guide research and development of more effective treatment. Methods: A literature review of Scopus, Medline, Embase, and CINAHL databases were searched from 2001 to 2 November 2021 with identified inclusion and exclusion criteria. Results: Out of 168 publications identified, 33 articles were included. Articles on three NMES applications were identified, including NMES-assisted strengthening, NMES-assisted gait, and NMES for spasticity reduction. NMES-assisted strengthening included the use of therapeutic exercises and cycling. NMES-assisted gait included the use of NMES to improve gait patterns. NMES-spasticity reduction included the use of transcutaneous electrical stimulation or NMES to decrease tone. Thirteen studies investigated NMES-assisted strengthening, eleven investigated therapeutic exercise and demonstrated significant improvements in muscle structure, strength, gross motor skills, walking speed, and functional mobility; three studies investigated NMES-assisted cycling and demonstrated improved gross motor skills and walking distance or speed. Eleven studies investigated NMES-assisted gait and demonstrated improved muscle structure, strength, selective motor control, gross motor skills, and gait mechanics. Seven studies investigated NMES for spasticity reduction, and five of the seven studies demonstrated reduced spasticity. Conclusion: A growing body of evidence supports the use of NMES-assisted strengthening, NMES-assisted gait, and NMES for spasticity reduction to improve functional mobility for individuals with spastic CP. Evidence for NMES to augment exercise in individuals with spastic CP remains limited. NMES protocols and parameters require further clarity to translate knowledge to clinicians. Future research should be completed to provide richer evidence to transition to more robust clinical practice.

Efficacy and safety of neuromuscular electrical stimulation in the prevention of pressure injuries in critically ill patients: a randomized controlled trial

Background

Pressure injuries (PIs), especially in the sacral region are frequent, costly, and increase morbidity and mortality of patients in an intensive care unit (ICU). These injuries can occur as a result of prolonged pressure and/or shear forces. Neuromuscular electrical stimulation (NMES) can increase muscle mass and improve local circulation, potentially reducing the incidence of PI.

Methods

We performed a randomized controlled trial to assess the efficacy and safety of NMES in preventing PI in critically ill patients. We included patients with a period of less than 48 h in the ICU, aged ≥ 18 years. Participants were randomly selected (1:1 ratio) to receive NMES and usual care (NMES group) or only usual care (control group—CG) until discharge, death, or onset of a PI. To assess the effectiveness of NMES, we calculated the relative risk (RR) and number needed to treat (NNT). We assessed the muscle thickness of the gluteus maximus by ultrasonography. To assess safety, we analyzed the effects of NMES on vital signs and checked for the presence of skin burns in the stimulated areas. Clinical outcomes were assessed by time on mechanical ventilation, ICU mortality rate, and length of stay in the ICU.

Results

We enrolled 149 participants, 76 in the NMES group. PIs were present in 26 (35.6%) patients in the CG and 4 (5.3%) in the NMES group (p ˂ 0.001). The NMES group had an RR = 0.15 (95% CI 0.05–0.40) to develop a PI, NNT = 3.3 (95% CI 2.3–5.9). Moreover, the NMES group presented a shorter length of stay in the ICU: Δ = − 1.8 ± 1.2 days, p = 0.04. There was no significant difference in gluteus maximus thickness between groups (CG: Δ = − 0.37 ± 1.2 cm vs. NMES group: Δ = 0 ± 0.98 cm, p = 0.33). NMES did not promote deleterious changes in vital signs and we did not detect skin burns.

Conclusions

NMES is an effective and safe therapy for the prevention of PI in critically ill patients and may reduce length of stay in the ICU.

Trial registration RBR-8nt9m4. Registered prospectively on July 20th, 2018, https://ensaiosclinicos.gov.br/rg/RBR-8nt9m4

Local and Contralateral Effects after the Application of Neuromuscular Electrostimulation in Lower Limbs

Neuromuscular electrostimulation (NMES) has been used mainly as a method to promote muscle strength, but its effects on improving blood flow are less well known. The aim of this study is to deepen the knowledge about the local and contralateral effects of the application of symmetric biphasic square currents on skin temperature (Tsk). An experimental pilot study was developed with a single study group consisting of 45 healthy subjects. Thermographic evaluations were recorded following the application of NMES to the anterior region of the thigh. The results showed an increase in the maximal Tsk of 0.67% in the anterior region of the thigh where the NMES was applied (p < 0.001) and an increase of 0.54% (p < 0.01) due to cross-education effects, which was higher when the NMES was applied on the dominant side (0.79%; p < 0.01). The duration of the effect was 20 min in the dominant leg and 10 min in the nondominant one. The application of a symmetrical biphasic current (8 Hz and 400 μs) creates an increase in the maximal Tsk at the local level. A temperature cross-education effect is produced, which is greater when the NMES is applied on the dominant side. This could be a useful noninvasive measurement tool in NMES treatments.

A randomised controlled trial of neuromuscular stimulation in non-operative venous disease improves clinical and symptomatic status

BACKGROUND

This randomised controlled trial investigates the dosing effect of neuromuscular electrical stimulation (NMES) in patients with chronic venous disease (CVD).

METHODS

Seventy-six patients with CEAP C3-C5 were randomised to Group A (no NMES), B (30 minutes of NMES daily) or C (60 minutes of NMES daily). Primary outcome was percentage change in Femoral Vein Time Averaged Mean Velocity (TAMV) at 6 weeks. Clinical severity scores, disease-specific and generic quality of life (QoL) were assessed.

RESULTS

Seventy-six patients were recruited - mean age 60.8 (SD14.4) and 47:29 male. Six patients lost to follow-up. Percentage change in TAMV (p<0.001) was significantly increased in Groups B and C. Aberdeen Varicose Veins Questionnaire Score (-6.9, p=0.029) and Venous Clinical Severity Score (-4, p-0.003) improved in Group C, and worsened in Group A (+1, p=0.025).

CONCLUSIONS

Daily NMES usage increases flow parameters, with twice daily usage improving QoL and clinical severity at 6 weeks in CVD patients.

Is Low-Frequency Electrical Stimulation a Tool for Recovery after a Water Rescue? A Cross-Over Study with Lifeguards

This study aimed to evaluate the degree to which transcutaneous electrical stimulation (ES) enhanced recovery following a simulated water rescue. Twenty-six lifeguards participated in this study. The rescue consisted of swimming 100 m with fins and rescue-tube: 50 m swim approach and 50 m tow-in a simulated victim. Blood lactate clearance, rated perceived effort (RPE), and muscle contractile properties were evaluated at baseline, after the water rescue, and after ES or passive-recovery control condition (PR) protocol. Tensiomiography, RPE, and blood lactate basal levels indicated equivalence between both groups. There was no change in tensiomiography from pre to post-recovery and no difference between recovery protocols. Overall-RPE, legs-RPE and arms-RPE after ES (mean ± SD; 2.7 ± 1.53, 2.65 ± 1.66, and 2.30 ± 1.84, respectively) were moderately lower than after PR (3.57 ± 2.4, 3.71 ± 2.43, and 3.29 ± 1.79, respectively) (p = 0.016, p = 0.010, p = 0.028, respectively). There was a significantly lower blood lactate level after recovery in ES than in PR (mean ± SD; 4.77 ± 1.86 mmol·L^-1 vs. 6.27 ± 3.69 mmol·L^-1; p = 0.045). Low-frequency ES immediately after a water rescue is an effective recovery strategy to clear out blood lactate concentration.

Daily use of a muscle pump activator device reduces duration of hospitalization and improves early graft outcomes post-kidney transplantation: A randomized controlled trial

INTRODUCTION

Kidney and simultaneous pancreas-kidney (SPK) transplant recipients can have prolonged postoperative hospitalization due to edema. Thrombo-embolic-deterrent (TED) stockings with intermittent pneumatic compression devices (TED+IPC) have been used to improve venous return during the perioperative period. The objective of this trial was to evaluate the effects of TED+IPC vs. muscle pump activator (MPA) devices on factors that could reduce postoperative complications and duration of hospitalization.

METHODS

In this single-center, prospective, randomized, controlled trial, 221 kidney and SPK transplant recipients were randomized to either wearing TED+IPC or MPA for six days postoperatively. Groups were compared with respect to postoperative urine output, lower limb edema, weight, days in hospital, mobility, serum creatinine, delayed graft function, need for dialysis, and lower extremity blood flow.

RESULTS

Patients in the MPA group had significantly higher urine output and less increase in mid-calf leg circumference and weight gain compared to the TED+IPC group (p=0.003, p=0.001, and p=0.003, respectively). The MPA group also experienced shorter hospitalization (p=0.038), higher femoral vein velocity (p=0.001), and took more steps (p=0.009). Incidence of delayed graft function (p=0.72) and number of dialysis runs (p=0.39) was not different between study groups. Subgroup analysis of primary endpoints in donation after cardiac death recipients and SPK recipients did not yield any significance between the study arms.

CONCLUSIONS

Postoperative use of the MPA device increases urine output, decreases leg edema, minimizes weight gain, and decreases duration of hospitalization after kidney transplantation. A larger and longer-term trial is needed to evaluate the impact on graft function.

Clinical applications of laser speckle contrast imaging: a review

When a biological tissue is illuminated with coherent light, an interference pattern will be formed at the detector, the so-called speckle pattern. Laser speckle contrast imaging (LSCI) is a technique based on the dynamic change in this backscattered light as a result of interaction with red blood cells. It can be used to visualize perfusion in various tissues and, even though this technique has been extensively described in the literature, the actual clinical implementation lags behind. We provide an overview of LSCI as a tool to image tissue perfusion. We present a brief introduction to the theory, review clinical studies from various medical fields, and discuss current limitations impeding clinical acceptance.

Use of a Muscle Pump Activator Leads to Improved Lower Limb Edema, Lower Limb Blood Flow, and Urine Output Compared With Standard TED Stockings and Compression Devices Following Kidney Transplant: A Randomized Controlled Trial

OBJECTIVE

The aim of this study was to evaluate the effects of using thromboembolic deterrent (TED) stockings and intermittent pneumatic compression (IPC) vs a muscle pump activator (MPA) device on limb edema and patient satisfaction after transplant.

METHODS

In this single-center randomized controlled trial, 118 patients were randomly assigned to wear TED + IPC (n = 64) or the MPA device (n = 54) from postoperative days 1 to 6. We measured patients' weight and lower leg and thigh circumferences daily. Ultrasonography of the allograft and lower limbs was carried out on postoperative days 1 and 5 to assess resistive index in the transplanted kidney and flow in the femoral vein. We monitored urine output and serum creatinine level.

RESULTS

We observed a significant increase in calf and thigh circumference from baseline in the TED + IPC group but not in the MPA group (2.3 [SD, 1] cm vs 0.25 [SD, 0.8] cm, respectively, P < .002). Ultrasonography showed higher femoral vein velocities in the MPA group than the TED + IPC group (0.5 [SD, 0.2] cm, P < .001). The mean total urine output in 6 days was higher in the MPA group than the TED + IPC group (P = .05), which corresponded to large change in TED + IPC weight of 6.2 kg vs 2.1 kg in the MPA group (P = .04). Patients were more satisfied with the use of the MPA device than TED + IPC. No major complications were encountered in either group.

CONCLUSIONS

This is the first study to show that the use of an MPA device in the immediate postoperative period following kidney transplant leads to decreased lower limb edema and increased total urine output. Patients were more satisfied with the use of the MPA device than TED + IPC.

A Novel Approach to Overcome Movement Artifact When Using a Laser Speckle Contrast Imaging System for Alternating Speeds of Blood Microcirculation

The laser speckle contrast imager (LSCI) provides a powerful yet simple technique for measuring microcirculatory blood flow. Ideal for blood dynamic responses, the LSCI is used in the same way as a conventional Laser Doppler Imager (LDI). However, with a maximum skin depth of approximately 1 mm, the LSCI is designed to focus on mainly superficial blood flow. It is used to measure skin surface areas of up to 15 cm x 20 cm. The new technique introduced in this paper accounts for alternating speeds of microcirculations; i.e. both slow and fast flow flux measurement using the LSCI. The novel technique also overcomes LSCI's biggest shortcoming, which is high sensitivity to artifact movement. An adhesive opaque patch (AOP) is introduced for satisfactory recording of microcirculatory blood flow, by subtracting the LSCI signal from the AOP from the laser speckle skin signal. The optimal setting is also defined because the LSCI is most powerful when flux changes are measured relative to a reference baseline, with blood microcirculatory flux expressed as a percentage change from the baseline. These changes may be used for analyzing the status of the blood flow system.