Intervention effect of neuromuscular electrical stimulation on ICU acquired weakness: A meta-analysis

Post-Intensive Care Syndrome as a Burden for Patients and Their Caregivers: A Narrative Review

Millions of critically ill patients are discharged from intensive care units (ICUs) every year. These ICU survivors may suffer from a condition known as post-intensive care syndrome (PICS) which includes a wide range of cognitive, psychological, and physical impairments. This article will provide an extensive review of PICS. ICU survivors may experience cognitive deficits in memory and attention, with a slow-down of mental processing and problem-solving. From psychological perspectives, depression, anxiety, and post-traumatic stress disorder are the most common issues suffered after ICU discharge. These psycho-cognitive impairments might be coupled with ICU-acquired weakness (polyneuropathy and/or myopathy), further reducing the quality of life, the ability to return to work, and other daily activities. The burden of ICU survivors extends to families too, leading to the so-called PICS-family (or PICS-F), which entails the psychological impairments suffered by the family and, in particular, by the caregiver of the ICU survivor. The development of PICS (and PICS-F) is likely multifactorial, and both patient- and ICU-related factors may influence it. Whilst the prevention of PICS is complex, it is important to identify the patients at higher risk of PICS, and clinicians should be aware of the tools available for diagnosis. Stakeholders should implement strategies to achieve PICS prevention and to support its effective treatment during the recovery phase with dedicated pathways and supporting care.

Guideline on positioning and early mobilisation in the critically ill by an expert panel

A scientific panel was created consisting of 23 interdisciplinary and interprofessional experts in intensive care medicine, physiotherapy, nursing care, surgery, rehabilitative medicine, and pneumology delegated from scientific societies together with a patient representative and a delegate from the Association of the Scientific Medical Societies who advised methodological implementation. The guideline was created according to the German Association of the Scientific Medical Societies (AWMF), based on The Appraisal of Guidelines for Research and Evaluation (AGREE) II. The topics of (early) mobilisation, neuromuscular electrical stimulation, assist devices for mobilisation, and positioning, including prone positioning, were identified as areas to be addressed and assigned to specialist expert groups, taking conflicts of interest into account. The panel formulated PICO questions (addressing the population, intervention, comparison or control group as well as the resulting outcomes), conducted a systematic literature review with abstract screening and full-text analysis and created summary tables. This was followed by grading the evidence according to the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence and a risk of bias assessment. The recommendations were finalized according to GRADE and voted using an online Delphi process followed by a final hybrid consensus conference. The German long version of the guideline was approved by the professional associations. For this English version an update of the systematic review was conducted until April 2024 and recommendation adapted based on new evidence in systematic reviews and randomized controlled trials. In total, 46 recommendations were developed and research gaps addressed.

[Positioning therapy for intensive care patients]

The current S3 guideline, "Positioning Therapy and Mobilization of Critically Ill Patients in Intensive Care Units", introduces methodological changes and substantive updates compared to the previous version. Additionally, new evidence-based insights with specified PICO questions have been integrated, aiming for a more precise application of recommendations in clinical practice and thus enhancing the care of critically ill patients.A notable aspect is the more nuanced approach to early mobilization, which is recommended to commence within the first 72 hours of ICU admission. A staged concept and score-based mobilization schema facilitate improved patient rehabilitation. Mobilization should be standard of care, i.e., immobilization should be ordered by the physician. The guideline provides suggestions for the duration and additional mobilization measures to ensure patients stand, transfer actively from bed to chair, or walk as frequently as possible. These recommendations apply even during ECMO therapy, highlighting the importance of early mobilization.Further updates include semi-recumbent positions of at least 40° in intubated patients, with careful consideration of potential side effects. Continuous lateral rotation therapy (CLRT) is not advised due to the progress in intensive care therapy, shifting from deep sedation toward responsive patient management.Prone positioning (PP) involves rotating the patient 180° onto the ventral side. It is recommended as a therapeutic option for invasively ventilated patients with ARDS and impaired arterial oxygenation (PaO2/FiO2 <150mmHg), with a recommended minimum duration of 12 hours, ideally 16 hours. Special recommendations apply, for example, to COVID-19 patients with acute hypoxemic respiratory failure, where awake proning should be considered.Additionally, new chapters have been introduced focusing on assistive devices and neuromuscular electrical stimulation.

The effect of electrical stimulation in critical patients: a meta-analysis of randomized controlled trials

Objectives

While electrical stimulation has been demonstrated to improve medical research council (MRC) scores in critically ill patients, its effectiveness remains a subject of debate. This meta-analysis aimed to discuss recent insights into the effectiveness of electrical stimulation in improving muscle strength and its effects on different clinical outcomes in critically ill adults.

Methods

A comprehensive search of major electronic databases, including PubMed, Cochrane Library, and Embase, was conducted from inception to June 15, 2024, to identify randomized controlled trials (RCTs) that evaluated the effects of electrical stimulation in critically ill patients. The analysis focused on comparing electrical stimulation to standard care, sham interventions, or placebo. Outcomes of interest included MRC scores, duration of mechanical ventilation (MV), mortality rate, and intensive care unit (ICU) and hospital length of stay (LOS).

Results

A total of 23 RCTs, including 1798 patients, met the inclusion criteria. The findings demonstrated a significant benefit of electrical stimulation over usual care in enhancing global muscle strength, as measured by MRC scores (MD =3.62, 95% CI 0.94 to 6.30, p = 0.0008, I2 = 87%). While subgroup analysis of electrical muscle stimulation (EMS) demonstrated no significant effect on ICU LOS, sensitivity analysis indicated a potential reduction in ICU LOS for both EMS (MD = -11.0, 95% CI -21.12 to -0.88, p = 0.03) and electrical stimulation overall (MD = -1.02, 95% CI -1.96 to -0.08, p = 0.03) compared to the control group. In addition, sensitivity analysis suggested that both electrical stimulation (MD = -2.38, 95% CI -3.81 to -0.94, p = 0.001) and neuromuscular electrical stimulation (NMES) specifically (MD = -2.36, 95% CI -3.85 to -0.88, p = 0.002) may contribute to a decrease in hospital LOS. No statistically significant differences were observed in mortality or duration of MV.

Conclusion

Electrical stimulation appears to be an effective intervention for improving MRC scores in critically ill patients. However, further research is warranted to explain the potential effects of electrical stimulation on hospital LOS and ICU LOS.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Effect of neuromuscular electrical stimulation and early physical activity on ICU-acquired weakness in mechanically ventilated patients: A randomized controlled trial

BACKGROUND

Intensive care unit-acquired weakness (ICU-AW) is common in critically ill patients and increases the duration of mechanical ventilation (MV) and weaning time. Early mobilization, range of motion (ROM) exercises, and neuromuscular electrical stimulation (NMES) can prevent ICU-AW by maintaining muscle mass. However, studies highlighting the effects of combining NMES with early physical activity in ICU patients are limited.

AIM

To evaluate the effect of NMES and early physical activity on ICU-AW in mechanically ventilated patients.

STUDY DESIGN

A single-blinded randomized controlled trial was conducted in Alexandria, Egypt. Patients were randomly assigned to one of four groups: NMES, ROM, combined therapy (ROM + NMES), or conventional care (control group). The Medical Research Council (MRC) scale was used to assess the ICU-AW for the study patients over a 7-day period. The duration of the patient's MV and ICU stays were recorded.

RESULTS

Of the 180 patients who were assessed for eligibility, 124 were randomly assigned to one of four groups: 32 patients in ROM exercises, 30 in NMES, 31 in combined therapy (ROM + NMES), and 31 in the control group. On day 7, ROM + NMES and NMES groups showed higher MRC scores than ROM and control groups (50.37 ± 2.34, 49.77 ± 2.19, 44.97 ± 3.61, and 41.10 ± 3.84, respectively). ANOVA test results indicated significant differences (p < .001) across the four groups. ICU-AW occurred in 0% of the ROM + NMES group, 60% of the ROM group, 13% of the NMES group, and 100% of the control group (p < .001). The MV duration (in days) in the ROM + NMES group was shorter (12.80 ± 3.800) than in the ROM, NMES, or control groups (21.80 ± 4.460, 18.73 ± 4.748, and 20.70 ± 3.932, respectively). ICU-LOS was shorter in the ROM + NMES group (17.43 ± 3.17 days) compared with the ROM group (22.53 ± 4.51 days), the NMES group (21.10 ± 5.0 days), and the control group (21.50 ± 4.42 days) with significant differences (p < .001) between the four groups.

CONCLUSION

Daily sessions of NMES and early physical activity were well tolerated, preserved muscle strength, prevented ICU-AW, and decreased the duration of the MV and ICU stay.

RELEVANCE TO CLINICAL PRACTICE

The findings of this study support the use of NMES and early physical exercises by critical care nurses as part of routine care for critically ill patients.

Association of tissue oxygen saturation levels with skeletal muscle injury in the critically ill

This study aimed to investigate the association between the level of tissue oxygen saturation (StO2) and quadriceps/skeletal muscle dysfunction, measured using the Medical Research Council (MRC) scale and ultrasonography, in critically ill patients. Thirty-four patients hospitalized at the Critical Care Medicine Center of Kindai University Hospital, between January 2022 and March 2023, were enrolled in this study. The StO2 of the quadriceps muscle was measured via near-infrared spectroscopy. Muscle atrophy was measured by the thickness, cross-sectional area (CSA), and echo intensity of the rectus femoris (RF). These values were evaluated every alternate day until 13 days after admission or until discharge, whichever occurred first. Muscle weakness was assessed using the sum score of the MRC scale (MRC-SS), with the patient sitting at bedside. The mean age of the patients was 67.3 ± 15.3 years, and 20 (59%) were men. Seven patients (21%) were admitted for trauma, and 27 (79%) were admitted for medical emergencies or others. The mean score for the MRC-SS was 51.0 ± 7.9 points. RF thickness and CSA significantly decreased after day 7 (p < 0.05). There were no significant changes in StO2 levels during hospitalization. However, there were positive correlations between the nadir StO2 during hospitalization and MRC-SS, and changes in RF thickness and CSA at discharge (r = 0.41, p = 0.03; r = 0.37, p = 0.03; and r = 0.35, p = 0.05, respectively). StO2 in the quadriceps muscle may be useful for predicting muscle atrophy and dysfunction in patients with critical illnesses.

Blood flow restriction as a potential therapy to restore physical function following COVID-19 infection

Accumulating evidence indicates that some COVID-19 survivors display reduced muscle mass, muscle strength, and aerobic capacity, which contribute to impairments in physical function that can persist for months after the acute phase of illness. Accordingly, strategies to restore muscle mass, muscle strength, and aerobic capacity following infection are critical to mitigate the long-term consequences of COVID-19. Blood flow restriction (BFR), which involves the application of mechanical compression to the limbs, presents a promising therapy that could be utilized throughout different phases of COVID-19 illness. Specifically, we hypothesize that: 1) use of passive BFR modalities can mitigate losses of muscle mass and muscle strength that occur during acute infection and 2) exercise with BFR can serve as an effective alternative to high-intensity exercise without BFR for regaining muscle mass, muscle strength, and aerobic capacity during convalescence. The various applications of BFR may also serve as a targeted therapy to address the underlying pathophysiology of COVID-19 and provide benefits to the musculoskeletal system as well as other organ systems affected by the disease. Consequently, we present a theoretical framework with which BFR could be implemented throughout the progression from acute illness to outpatient rehabilitation with the goal of improving short- and long-term outcomes in COVID-19 survivors. We envision that this paper will encourage discussion and consideration among researchers and clinicians of the potential therapeutic benefits of BFR to treat not only COVID-19 but similar pathologies and cases of acute critical illness.

A Global Survey on Diagnostic, Therapeutic and Preventive Strategies in Intensive Care Unit-Acquired Weakness

Background and Objectives: Intensive care unit-acquired weakness (ICU-AW) is one of the most frequent neuromuscular complications in critically ill patients. We conducted a global survey to evaluate the current practices of diagnostics, treatment and prevention in patients with ICU-AW. Materials and Methods: A pre-survey was created with international experts. After revision, the final survey was endorsed by the European Society of Intensive Care Medicine (ESICM) using the online platform SurveyMonkey®. In 27 items, we addressed strategies of diagnostics, therapy and prevention. An invitation link was sent by email to all ESICM members. Furthermore, the survey was available on the ESICM homepage. Results: A total of 154 healthcare professionals from 39 countries participated in the survey. An ICU-AW screening protocol was used by 20% (28/140) of participants. Forty-four percent (62/141) of all participants reported performing routine screening for ICU-AW, using clinical examination as the method of choice (124/141, 87.9%). Almost 63% (84/134) of the participants reported using current treatment strategies for patients with ICU-AW. The use of treatment and prevention strategies differed between intensivists and non-intensivists regarding the reduction in sedatives (80.0% vs. 52.6%, p = 0.002), neuromuscular blocking agents (76.4% vs. 50%, p = 0.004), corticosteroids (69.1% vs. 37.2%, p < 0.001) and glycemic control regimes (50.9% vs. 23.1%, p = 0.002). Mobilization and physical activity are the most frequently reported treatment strategies for ICU-AW (111/134, 82.9%). The availability of physiotherapists (92/134, 68.7%) and the lack of knowledge about ICU-AW within the medical team (83/134, 61.9%) were the main obstacles to the implementation of the strategies. The necessity to develop guidelines for the screening, diagnosing, treatment and prevention of ICU-AW was recognized by 95% (127/133) of participants. Conclusions: A great heterogeneity regarding diagnostics, treatment and prevention of ICU-AW was reported internationally. Comprehensive guidelines with evidence-based recommendations for ICU-AW management are needed.

In-hospital electrical muscle stimulation for patients early after heart failure decompensation: results from a prospective randomised controlled pilot trial

BACKGROUND

Electrical muscle stimulation (EMS) is being evaluated as a possible alternative to exercise training to improve functional capacity in severely deconditioned patients with heart failure (HF). However, there is insufficient data on delayed effects of EMS starting early after decompensation. The aim of this study was to determine the impact of a short inpatient EMS intervention in severely deconditioned patients with HF on functional capacity and quality of life (QoL) over a follow-up period of 1 month.

METHODS

This is a prospective randomised sham-controlled pilot study. 45 patients hospitalised for decompensated systolic HF (58% men, mean age 66.4±10.2 years) were randomised to EMS (n=22) or sham stimulation (n=23) of lower limbs starting within 3 days after admission. The intervention included 7-10 sessions lasting from 30 to 90 min. The 6-minute walking test distance (6-MWTD), Duke Activity Status Index (DASI) and Minnesota Living with Heart Failure Questionnaire (MLHFQ) were evaluated at baseline, discharge and after 1 month.

RESULTS

All patients completed the programme with good EMS tolerance. 37 patients were included in the final analysis. At discharge, 6-MWTD improved from 206,1±61,3 to 299.5±91 m, DASI from 12.1±5.6 to 18.3±7.2 and MLHFQ from 55.6±8.5 to 34.2±9 with EMS compared with smaller improvements in the sham group (p<0.05 for all). One month after discharge, improvements in the EMS group remained significant for MLHFQ (p=0.004) and DASI (p=0.042) and statistically non-significant for 6-MWTD compared with the sham group.

CONCLUSIONS

Short-term in-hospital EMS leads to improvements in functional capacity and QoL in selected patients early after HF decompensation that are retained over 1 month after discharge and therefore may serve as initial intervention to improve physical capacity or as a bridge to further conventional exercise training. Larger studies are required to evaluate individual responses to an early initiation of EMS in decompensated HF as well as long-term effects.

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

Passive motion of the lower extremities in sedated and ventilated patients in the ICU - a systematic review of early effects and replicability of Interventions

Early mobilization, which includes active / passive motion in bed along with mobilization out of bed, is recommended to prevent the development of intensive care unit acquired-weakness (ICU-AW) for patients with critical illness on the intensive care unit. To date, the impact of passive motion of the lower extremities in sedated and ventilated patients remains unclear. The aim of the study is to systematically review and summarize the currently available randomized controlled trials in English or German language on the impact of passive motion of the lower extremities in sedated and ventilated patients ≥ 18 years in the intensive care unit on musculature, inflammation and immune system and the development of intensive care unit-acquired weakness and to evaluate the replicability of interventions and the methodological quality of included studies. A systematic literature search was performed up to 20th February 2022 in the databases Medline, Embase, Cochrane Library, CINAHL and PEDro. The description of the intervention (TIDieR checklist) and the methodological quality (Downs and Black checklist) were assessed. Five studies were included in the qualitative syntheses. On average, the studies were rated with 6.8 out of 12 points according to the TIDieR checklist. For the methodological quality an average of 19.8 out of 27 points on the Downs and Black checklist was reported. The results of included studies indicated that muscle loss may be reduced by passive manual movement, passive cycling and passive motion on a continuous passive motion-unit. In addition, positive effects were reported on the reduction of nitrosative stress and the immune response. The impact on the development of ICU-AW remains unclear. In conclusion, passive movement show a slight tendency for beneficial changes on cellular level in sedated and ventilated patients in the ICU within the first days of admission, which may indicate a reduction of muscle wasting and could prevent the development of ICU-AW. Future randomized controlled trials should use larger samples, use complete intervention description, use a comparable set of outcome measures, use rigorous methodology and examine the effect of passive motion on the development of ICU-AW.

Recovery and long term functional outcome in people with critical illness polyneuropathy and myopathy: a scoping review

BACKGROUND

Intensive care unit acquired weakness (ICUAW), embraces an array of disorders labeled "critical illness polyneuropathy" (CIP), "critical illness myopathy" (CIM) or "critical illness polyneuromyopathy" (CIPNM). Several studies have addressed the various characteristics of ICUAW, but the recovery is still unclear.

OBJECTIVE

The present review investigated the recovery and the long-term functional outcome of subjects with ICUAW, whether the types of ICUAW have different outcomes and whether there is any supporting evidence.

METHODS

Literature search was performed from MEDLINE/PubMed, CINAHL, EMBASE, PeDro, Web of Science and Scopus. Inclusion criteria were: i) sample size including five or more subjects; ii) subjects who suffered from ICUAW and/or CIP, CIM and CIP/CIM; iii) ICUAW ascertained by EMG. Follow-ups longer than one year were defined as long-term.

RESULTS

Twenty-nine studies met the inclusion criteria. In total, 788 subjects with ICUAW were enrolled: 159 (20.1%) died and 588 (74.6%) were followed. Of all the included patients, 613 (77.7%) had CIP, 82 (10.4%) CIM and 56 (7.1%) CIP/CIM. Overall, 70.3% of the subjects with ICUAW fully recovered. Seven (24.1%) studies had a follow-up longer than 1 year (range 2-8) with 173 (21.9%) subjects enrolled globally and 108 followed. Of these subjects, 88.8% gained full recovery. Most of the studies did not use proper functional scales and only 4 and 3 studies employed the Barthel scale and the Functional Independence Measure (FIM) scale. Differentiation between the types of ICUAW was performed in 7 studies, but only 3 studies reported that subjects with CIM had a better prognosis and earlier recovery than subjects with CIP/CIM.

CONCLUSIONS

Subjects with ICUAW could achieve good recovery and could improve at follow-up. However, the quality of the published studies due to short follow-ups and the paucity of defined outcome measures require confirms.

[Intensive Care Unit-Acquired Weakness : A nationwide survey on diagnostics, monitoring and treatment strategies on German intensive care units]

Hintergrund

Die „Intensive Care Unit-Acquired Weakness“ (ICU-AW) ist eine der häufigsten Ursachen für eine neuromuskuläre Dysfunktion in der Intensivmedizin. Gegenwärtig fehlen evidenzbasierte Empfehlungen zur Diagnostik, zum Monitoring und zu therapeutischen Maßnahmen.

Ziel der Arbeit

Die Erfassung des derzeitigen Vorgehens bei Diagnostik, Monitoring und präventiven und therapeutischen Ansätzen bei der ICU-AW auf deutschen Intensivstationen.

Material und Methoden

Onlinebefragung von 448 Mitgliedern des Wissenschaftlichen Arbeitskreises Intensivmedizin (WAKI) und des Wissenschaftlichen Arbeitskreises Neuroanästhesie (WAKNA).

Ergebnisse

Insgesamt wurden 68/448 (15,2 %) Fragebogen ausgewertet. Bei 13,4 % (9/67) der Befragten existiert ein strukturiertes diagnostisches Vorgehen zur Detektion der ICU-AW. Für Screening (60/68; 88,2 %) und Verlaufsbeurteilung (57/65; 87,7 %) wird die klinische Untersuchung präferiert. Etablierte Scores, wie der „Medical Research Council sum score“ (MRC-SS) spielen für Screening und Verlaufskontrolle der ICU-AW eine untergeordnete Rolle (7/68; 10,3 % und 7/65; 10,8 %). Mobilisation (45/68; 66,2 %) und Sedativareduktion (38/68; 55,9 %) stellen die häufigsten präventiven und therapeutischen Ansätze dar. Ein Mangel an Physiotherapeuten (64/68; 94,1 %) und Pflegekräften (57/68; 83,8 %) wird als Hauptdefizit bei der Versorgung von Patienten mit ICU-AW identifiziert. Insgesamt 91,2 % (62/68) der Befragten befürworten die Erstellung evidenzbasierter Empfehlungen zur Diagnostik, zum Monitoring und zu therapeutischen Ansätzen bei ICU-AW.

Diskussion

Ein einheitliches Konzept für Diagnostik, Monitoring, Prävention und Therapie der ICU-AW auf deutschen Intensivstationen fehlt weitgehend. Innovative diagnostische Ansätze könnten in Zukunft helfen, Patienten mit einem hohem Risiko für eine ICU-AW frühzeitig zu detektieren, präventive Maßnahmen einzuleiten sowie wertvolle prognostische Informationen zu gewinnen.

Zusatzmaterial online

Die Online-Version dieses Beitrags (10.1007/s00101-022-01089-9) enthält den der Studie zugrunde liegenden Fragebogen.

Effectiveness of neuromuscular electrostimulation in COPD subjects on mechanical ventilation. A systematic review and meta-analysis

OBJECTIVE

To estimate the effectiveness of Neuromuscular Electrostimulation (NMES) in adults with COPD undergoing MV.

METHOD

A sensitive search was performed in MEDLINE, Embase, CENTRAL, CINAHL and other resources. Randomized Controlled Clinical Trials (RCTs) or non-RCTs that enrolled adults with COPD on MV due to an exacerbation of their disease were included. Two independent reviewers screened, extracted information, and assessed the risk of bias (RoB 2 tool) and the certainty of evidence (GRADE approach) from the included studies.

RESULTS

Four RCTs (144 participants) were included. Subjects who underwent NMES were able to move from bed to chair independently in less time (MD = 4.98 days less; 95% CI -8.55 to -1.47; 2 RCTs; low certainty of the evidence) and they were fewer days on MV (MD = 2.89 days less; 95% CI -4.58 to -1.21); 3 RCTs; low certainty of the evidence) than the control group. However, the effect of NMES on muscle strength is unclear (very low certainty of the evidence).

CONCLUSIONS

NMES may improve functional independence and decrease MV time in adults with COPD; however, its effectiveness on muscle strength is uncertain. More and better RCTs are needed to determine with greater certainty the effectiveness of NMES in this population.

Electrically stimulated eccentric contraction during non-weight bearing knee bending exercise in the supine position increases oxygen uptake: A randomized, controlled, exploratory crossover trial

It is well known that prolonged bed rest induces muscle weakness, muscle atrophy, cardiovascular deconditioning, bone loss, a loss of functional capacity, and the development of insulin resistance. Neuromuscular electrical stimulation is anticipated to be an interventional strategy for disuse due to bed rest. A hybrid training system (HTS), synchronized neuromuscular electrical stimulation for voluntary exercise using an articular motion sensor, may increase the exercise load though bed rest. We assessed oxygen uptake or heart rate during knee bending exercise in the supine position on a bed both simultaneously combined with HTS and without HTS to evaluate exercise intensity on different days in ten healthy subjects (8 men and 2 women) by a randomized controlled crossover trial. The values of relative oxygen uptake during knee bending exercise with HTS were significantly greater than those during knee bending exercise without HTS (7.29 ± 0.91 ml/kg/min vs. 8.29 ± 1.06 ml/kg/min; p = 0.0115). That increment with HTS was a mean of 14.42 ± 13.99%. Metabolic equivalents during knee bending exercise with HTS and without HTS were 2.08 ± 0.26 and 2.39 ± 0.30, respectively. The values of heart rate during knee bending exercise with HTS were significantly greater than those during knee bending exercise without HTS (80.82 ± 9.19 bpm vs. 86.36 ± 5.50 bpm; p = 0.0153). HTS could increase exercise load during knee bending exercise which is easy to implement on a bed. HTS might be a useful technique as a countermeasure against the disuse due to bed rest, for example during acute care or the quarantine for infection prophylaxis.

Effect of Neuromuscular Electrical Stimulation on the Duration of Mechanical Ventilation

BACKGROUND

It has been proposed that neuromuscular or functional electrical stimulation may have effects on respiratory muscles through its systemic effects, similar to those produced by exercise training. However, its impact on the duration of invasive mechanical ventilation has not been adequately defined. We sought to evaluate the effect of neuromuscular or functional electrical stimulation on the duration of invasive mechanical ventilation in critically ill subjects.

METHODS

We systematically searched 3 databases up to August 2019 (ie, CENTRAL, MEDLINE, and EMBASE) as well as other resources to identify randomized controlled trials (RCTs) that evaluated the effects of neuromuscular or functional electrical stimulation compared to usual care/rehabilitation or placebo of neuromuscular or functional electrical stimulation on the duration of invasive mechanical ventilation.

RESULTS

After reviewing 1,200 single records, 12 RCTs (N = 530 subjects) fulfilled our eligibility criteria. Three studies included only subjects with COPD (n = 106 subjects), whereas the rest considered subjects with different diseases. The most frequently stimulated muscle group was the quadriceps. Neuromuscular or functional electrical stimulation may decrease the duration of invasive mechanical ventilation (mean difference = -2.68 d, 95% CI -4.35 to -1.02, I² = 50%, P = .002; 10 RCTs; low quality of evidence), and we are uncertain whether this effect may be more pronounced in subjects with COPD (mean difference = -2.90 d, 95% CI -4.58 to -1.23, I² = 9%, P < .001; 3 RCTs; very low quality of evidence).

CONCLUSIONS

Neuromuscular or functional electrical stimulation may slightly reduce the duration of invasive mechanical ventilation; we are uncertain whether these results are found in subjects with COPD compared to subjects receiving usual care or placebo, and the quality of the body of evidence is low to very low. More RCTs are needed with a larger number of subjects, with more homogeneous diseases and basal conditions, and especially with a more adequate methodological design.

Factors associated with electrical stimulation-induced performance fatigability are dependent upon stimulation location

NEW FINDINGS

What is the central question of this study? How does peripheral nerve stimulation (PNS) compare with neuromuscular electrical stimulation (NMES) used clinically to reduce muscle atrophy? What is the main finding and its importance? NMES resulted in progressive increases in M-wave duration and delay of muscle relaxation throughout a single stimulation protocol, findings not observed with PNS. This suggests PNS recruits from a wider pool of muscle fibres/motor units, providing a more favourable alternative to NMES for rehabilitation intervention.

ABSTRACT

Neuromuscular electrical stimulation (NMES) is increasingly viewed as a central tenet to minimise muscle loss during periods of disuse/illness - typically applied directly over a muscle belly. Peripheral nerve stimulation (PNS) is afforded less attention, despite providing a more global contractile stimulus to muscles. We investigated NMES versus PNS in relation to performance fatigability and peripheral contributions to voluntary force capacity. Two fatigue protocols were assessed separately: (1) over-quadriceps NMES and (2) peripheral (femoral) nerve stimulation (PNS). Before and after each session, a maximal voluntary contraction (MVC) was performed to assess force loss. Knee-extensor force was measured throughout to assess contractile function in response to submaximal electrical stimulation, and M-wave features quantified myoelectrical activity. NMES and PNS induced similar voluntary (MVC, NMES: -12 ± 9%, PNS: -10 ± 8%, both P < 0.001) and stimulated (NMES: -45 ± 12%, PNS -27 ± 27%, both P < 0.001) force reductions. Although distinct between protocols, myoelectrical indicators of muscle recruitment (M-wave area and amplitude) and nerve conduction time did not change throughout either protocol. Myoelectrical propagation speed, represented as M-wave duration, and the delay before muscle relaxation began both progressively increased during NMES only (P < 0.05 and P < 0.001, respectively). NMES myoelectrical changes suggested performance fatigability, indicating activation of superficial fibres only, which was not observed with PNS. This suggests PNS recruits a wider pool of muscle fibres and motor units and is a favourable alternative for rehabilitation. Future work should focus on implementing PNS interventions in clinically relevant scenarios such as immobilisation, care homes and critical illness.