Neuromuscular electrical stimulation as a possible means to prevent muscle tissue wasting in artificially ventilated and sedated patients in the intensive care unit: A pilot study

Electrical stimulation for investigating and improving neuromuscular function in vivo: Historical perspective and major advances

This historical review summarizes the major advances - particularly from the last 50 years - in transcutaneous motor-level electrical stimulation, which can be used either as a tool to investigate neuromuscular function and its determinants (electrical stimulation for testing; EST) or as a therapeutic/training modality to improve neuromuscular and physical function (neuromuscular electrical stimulation; NMES). We focus on some of the most important applications of electrical stimulation in research and clinical settings, such as the investigation of acute changes, chronic adaptations and pathological alterations of neuromuscular function with EST, as well as the enhancement, preservation and restoration of muscle strength and mass with NMES treatment programs in various populations. For both EST and NMES, several major advances converge around understanding and optimizing motor unit recruitment during electrically-evoked contractions, also taking into account the influence of stimulation site (e.g., muscle belly vs nerve trunk) and type (e.g., pulse duration, frequency, and intensity). This information is equally important both in the context of mechanistic research of neuromuscular function as well as for clinicians who believe that improvements in neuromuscular function are required to provide health-related benefits to their patients.

Short-Term Outcomes of Neuromuscular Electrical Stimulation in Critically Ill Patients

Muscle weakness acquired in the intensive care unit (ICU) adversely affects outcomes of ICU patients. This article reports the short-term respiratory effects of neuromuscular electrical stimulation (NMES) in critically ill patients. Patients were randomly assigned to an intervention group (NMES + conventional physiotherapy) and a control group (sham NMES + conventional physiotherapy). The application of NMES in the intervention group resulted in a significant decrease in the duration of mechanical ventilation and reduced the number of weaning trial failures. Other positive outcomes included reductions in the length of ICU stays and decreased mortality when compared with the control group.

Effectiveness of physical exercise and neuromuscular electrical stimulation interventions for preventing and treating intensive care unit-acquired weakness: A systematic review of randomized controlled trials

OBJECTIVE

Intensive care unit-acquired weakness is a frequent problem that develops as a secondary disorder while patients are suffering from life-threatening conditions. This study aimed to evaluate the effectiveness of physical exercise or neuromuscular electrical stimulation interventions on (i) preventing loss of muscle mass and weakness in critically ill patients admitted to intensive care units; (ii) recovering patients discharged from the intensive care unit with acquired weakness.

METHODS

A systematic review of randomized controlled trials was carried out, with studies identified in PubMed, Scopus, and Web of Science. The studies included assessed muscle mass and muscle strength, and performed a time × group analysis of effects. The risk of bias assessment was performed using the Revised Cochrane risk-of-bias tool for randomized trials.

RESULTS

Six trials with low risk of bias examined muscle mass, muscle strength, and functionality in 182 adult patients. In critically ill patients admitted to intensive care units, both neuromuscular electrical stimulation and bed/chair cycling for five to ten days prevented significant muscle loss. neuromuscular electrical stimulation in lower and upper limbs resulted in a significant reduction in the length of the hospitalization. In addition, cycle ergometer increased muscle strength and functionality. In patients discharged from the intensive care unit with acquired weakness, both neuromuscular electrical stimulation and physical exercise interventions increased muscle strength, but only physical exercise increased functionality.

CONCLUSIONS

Physical exercise and neuromuscular electrical stimulation interventions prevent excessive muscle mass loss in critically ill patients admitted to the intensive care unit and increase muscle strength in patients discharged from the intensive care unit with acquired weakness. Physical exercise seems more adequate for improving functionality.

Therapeutic Potential of Electromyostimulation (EMS) in Critically Ill Patients—A Systematic Review

Ample evidence exists that intensive care unit (ICU) treatment and invasive ventilation induce a transient or permanent decline in muscle mass and function. The functional deficit is often called ICU-acquired weakness with critical illness polyneuropathy (CIP) and/or myopathy (CIM) being the major underlying causes. Histopathological studies in ICU patients indicate loss of myosin filaments, muscle fiber necrosis, atrophy of both muscle fiber types as well as axonal degeneration. Besides medical prevention of risk factors such as sepsis, hyperglycemia and pneumonia, treatment is limited to early passive and active mobilization and one third of CIP/CIM patients discharged from ICU never regain their pre-hospitalization constitution. Electromyostimulation [EMS, also termed neuromuscular electrical stimulation (NMES)] is known to improve strength and function of healthy and already atrophied muscle, and may increase muscle blood flow and induce angiogenesis as well as beneficial systemic vascular adaptations. This systematic review aimed to investigate evidence from randomized controlled trails (RCTs) on the efficacy of EMS to improve the condition of critically ill patients treated on ICU. A systematic search of the literature was conducted using PubMed (Medline), CENTRAL (including Embase and CINAHL), and Google Scholar. Out of 1,917 identified records, 26 articles (1,312 patients) fulfilled the eligibility criteria of investigating at least one functional measure including muscle function, functional independence, or weaning outcomes using a RCT design in critically ill ICU patients. A qualitative approach was used, and results were structured by 1) stimulated muscles/muscle area (quadriceps muscle only; two to four leg muscle groups; legs and arms; chest and abdomen) and 2) treatment duration (≤10 days, >10 days). Stimulation parameters (impulse frequency, pulse width, intensity, duty cycle) were also collected and the net EMS treatment time was calculated. A high grade of heterogeneity between studies was detected with major cofactors being the analyzed patient group and selected outcome variable. The overall efficacy of EMS was inconclusive and neither treatment duration, stimulation site or net EMS treatment time had clear effects on study outcomes. Based on our findings, we provide practical recommendations and suggestions for future studies investigating the therapeutic efficacy of EMS in critically ill patients.

Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42021262287].

Modalities of Exercise Training in Patients with Extracorporeal Membrane Oxygenation Support

The aim of this qualitative systematic review is to summarize and analyze the different modalities of exercise training and its potential effects in patients on extracorporeal membrane oxygenation (ECMO) support. ECMO is an outbreaking, life-saving technology of the last decades which is being used as a gold standard treatment in patients with severe cardiac, respiratory or combined cardiorespiratory failure. Critically ill patients on ECMO very often present intensive care unit-acquired weakness (ICU-AW); thus, leading to decreased exercise capacity and increased mortality rates. Early mobilization and physical therapy have been proven to be safe and feasible in critically ill patients on ECMO, either as a bridge to lung/heart transplantation or as a bridge to recovery. Rehabilitation has beneficial effects from the early stages in the ICU, resulting in the prevention of ICU-AW, and a decrease in episodes of delirium, the duration of mechanical ventilation, ICU and hospital length of stay, and mortality rates. It also improves functional ability, exercise capacity, and quality of life. Rehabilitation requires a very careful, multi-disciplinary approach from a highly specialized team from different specialties. Initial risk assessment and screening, with appropriate physical therapy planning and exercise monitoring in patients receiving ECMO therapy are crucial factors for achieving treatment goals. However, more randomized controlled trials are required in order to establish more appropriate individualized exercise training protocols.

The effect of passive mobilization associated with blood flow restriction and combined with electrical stimulation on cardiorespiratory safety, neuromuscular adaptations, physical function, and quality of life in comatose patients in an ICU: a randomized controlled clinical trial

Background

Intensive care unit-acquired atrophy and weakness are associated with high mortality, a reduction in physical function, and quality of life. Passive mobilization (PM) and neuromuscular electrical stimulation were applied in comatose patients; however, evidence is inconclusive regarding atrophy and weakness prevention. Blood flow restriction (BFR) associated with PM (BFRp) or with electrical stimulation (BFRpE) was able to reduce atrophy and increase muscle mass in spinal cord-injured patients, respectively. Bulky venous return occurs after releasing BFR, which can cause unknown repercussions on the cardiovascular system. Hence, the aim of this study was to investigate the effect of BFRp and BFRpE on cardiovascular safety and applicability, neuromuscular adaptations, physical function, and quality of life in comatose patients in intensive care units (ICUs).

Methods

Thirty-nine patients will be assessed at baseline (T0–18 h of coma) and randomly assigned to the PM (control group), BFRp, or BFRpE groups. The training protocol will be applied in both legs alternately, twice a day with a 4-h interval until coma awake, death, or ICU discharge. Cardiovascular safety and applicability will be evaluated at the first training session (T1). At T0 and 12 h after the last session (T2), muscle thickness and quality will be assessed. Global muscle strength and physical function will be assessed 12 h after T2 and ICU and hospital discharge for those who wake up from coma. Six and 12 months after hospital discharge, physical function and quality of life will be re-assessed.

Discussion

In view of applicability, the data will be used to inform the design and sample size of a prospective trial to clarify the effect of BFRpE on preventing muscle atrophy and weakness and to exert the greatest beneficial effects on physical function and quality of life compared to BFRp in comatose patients in the ICU.

Trial registration

Universal Trial Number (UTN) Registry UTN U1111-1241-4344. Retrospectively registered on 2 October 2019. Brazilian Clinical Trials Registry (ReBec) RBR-2qpyxf. Retrospectively registered on 21 January 2020, http://ensaiosclinicos.gov.br/rg/RBR-2qpyxf/

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05916-z.

Effect of Graded Early Mobilization on Psychomotor Status and Length of Intensive Care Unit Stay in Mechanically Ventilated Patients

Introduction

The main purpose of this study was to evaluate the effectiveness of graded early mobilization on psychomotor status and duration of ICU stay of patients with mechanical ventilation.

Materials and methods

Results

In the control group mean FIM score was 17.40 (SD±4.88), and in the intervention group mean score was 65.70 (SD±12.18). The mean difference was statistically significant in the ‘t’ test (p-value > 0.001). In the control group, the mean GAD-7 score was 19.50 (SD±2.71), and in the intervention group the mean GAD-7 score was 7.5 (SD±2.59). The mean difference was statistically significant in the ‘t’ test. (p-value > 0.001). The mean length of ICU stay in the control group was 5.60 (SD±1.07) and in the intervention group it was 3.10 (SD±0.56). The mean difference was statistically significant in the ‘t’ test (p-value > 0.001).

Conclusion

This research showed that graded early mobilization was highly effective to improve the motor and psychological status of mechanically ventilated patients and reduce their length of ICU stay.

How to cite this article

Das B, Saha S, Kabir F, Hossain S. Effect of Graded Early Mobilization on Psychomotor Status and Length of Intensive Care Unit Stay in Mechanically Ventilated Patients. Indian J Crit Care Med 2021;25(4):416–420.

Early neuromuscular electrical stimulation reduces the loss of muscle mass in critically ill patients - A within subject randomized controlled trial

PURPOSE

To investigate the effect of Neuromuscular Electrical Stimulation (NMES) on muscle thickness, strength and morphological and molecular markers of the quadriceps.

MATERIALS AND METHODS

Adult critically ill patients with an expected prolonged stay received unilateral quadriceps NMES sessions for 7 consecutive days. Before and after the intervention period, quadriceps thickness was measured with ultrasound. After the intervention period, strength was assessed in cooperative patients and muscle biopsies were taken. Multivariable regression was performed to identify factors affecting muscle thickness loss.

RESULTS

Muscle thickness decreased less in the stimulated leg (-6 ± 16% versus -12 ± 15%, p = 0.014, n = 47). Strength was comparable. Opioid administration, minimal muscle contraction and more muscle thickness loss in the non-stimulated muscle were independently associated with better muscle thickness preservation. Stimulated muscles showed a shift towards larger myofibers and higher MyHC-I gene expression. NMES did not affect gene expression of other myofibrillary proteins, MuRF-1 or atrogin-1. Signs of myofiber necrosis and inflammation were comparable for both muscles.

CONCLUSIONS

NMES attenuated the loss of muscle mass, but not of strength, in critically ill patients. Preservation of muscle mass was more likely in patients receiving opioids, patients with a minimal muscle contraction during NMES and patients more prone to lose muscle mass.

TRIAL REGISTRATION

clinicaltrials.govNCT02133300.

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

Objective

The early use of neuromuscular electrical stimulation (NMES) to prevent intensive care unit-acquired weakness (ICU-AW) in critical patients is still a controversial topic. We conducted a systematic review to clarify the effectiveness of NMES in preventing ICU-AW.

Methods

The Cochrane Library, PubMed, EMBASE, MEDLINE, Web of Science, Ovid, CNKI, Wanfang, VIP, China Biology Medicine disc (CBMdisc) and other databases were searched for randomized controlled trials on the influence of NMES on ICU-AW. The studies were selected according to the inclusion and exclusion criteria. After data and quality were evaluated, a meta-analysis was performed by RevMan 5.3 software.

Results

A total of 11 randomized controlled trials with 576 patients were included. The meta-analysis results showed that NMES can improve muscle strength [MD = 1.78, 95% CI (0.44, 3.12, P = 0.009); shorten the mechanical ventilation (MV) time [SMD = −0.65, 95% CI (−1.03, −0.27, P = 0.001], ICU length of stay [MD = −3.41, 95% CI (−4.58, −4.24), P < 0.001], and total length of stay [MD = −3.97, 95% CI (−6.89, −1.06, P = 0.008]; improve the ability of patients to perform activities of daily living [SMD = 0.9, 95% CI (0.45, 1.35), P = 0.001]; and increase walking distance [MD = 239.03, 95% CI (179.22298.85), P < 0.001]. However, there is no evidence indicating that NMES can improve the functional status of ICU patients during hospitalization, promote the early awakening of patients or reduce mortality (P > 0.05).

Conclusion

Early implementation of the NMES intervention in ICU patients can prevent ICU-AW and improve their quality of life by enhancing their muscle strength and shortening the MV duration, length of stay in the ICU and total length of stay in the hospital.

Safety and potential benefits of physical therapy in adult patients on extracorporeal membrane oxygenation support: a systematic review

Scientific and technological advances, coupled with the work of multidisciplinary teams in intensive care units, have increased the survival of critically ill patients. An essential life support resource used in intensive care is extracorporeal membrane oxygenation. Despite the increased number of studies involving critically ill patients, few studies to date have demonstrated the safety and benefits of physical therapy combined with extracorporeal membrane oxygenation support. This review identified the clinical outcomes of physical therapy in adult patients on extracorporeal membrane oxygenation support by searching the MEDLINE®, PEDro, Cochrane CENTRAL, LILACS, and EMBASE databases and by manually searching the references of the articles published until September 2017. The database search retrieved 1,213 studies. Of these studies, 20 were included in this review, with data on 317 subjects (58 in the control group). Twelve studies reported that there were no complications during physical therapy. Cannula fracture during ambulation (one case), thrombus in the return cannula (one case), and leg swelling (one case) were reported in two studies, and desaturation and mild vertigo were reported in two studies. In contrast, improvements in respiratory/pulmonary function, functional capacity, muscle strength (with reduced muscle mass loss), incidence of myopathy, length of hospitalization, and mortality in patients who underwent physical therapy were reported. The analysis of the available data indicates that physical therapy, including early progressive mobilization, standing, ambulation, and breathing techniques, together with extracorporeal membrane oxygenation, is feasible, relatively safe, and potentially beneficial for critically ill adult patients.

Early mobilization for mechanically ventilated patients in the intensive care unit: a systematic review and meta-analysis

Background

Early mobilization (EM) is a regimen that was carried out by physiotherapists in a relatively early stage. It has been investigated by an increasing number of researchers. However, there has not been a meta-analysis concerning whether EM could benefit the clinical outcomes of critically ill patients requiring mechanical ventilation (MV). The present systematic review aims to evaluate the effect of EM compared with immobilization for mechanically ventilated patients.

Methods

A computerized literature search was performed in six databases for related articles from inception to June 2017. We included randomized controlled trials and controlled clinical trials and used the Physiotherapy Evidence Database scale to assess the quality of included studies. Primary outcomes were measures of muscle function, duration of MV, and incidence of mortality. Secondary outcomes were adverse effects and length of stay (LOS) in intensive care unit (ICU) and hospital.

Results

Eight trials were included; of those, only one study without standard EM reported that the intervention was invalid to improve the outcomes. The result of meta-analysis indicated that EM shortened the duration of MV; however, it had no positive effect on mortality and LOS in ICU.

Conclusions

This review suggests that EM improves the muscle function and ventilation duration. Further research highlighting standard intervention and specific groups is needed.

Physical rehabilitation interventions in the intensive care unit: a scoping review of 117 studies

BACKGROUND

Physical rehabilitation (PR) interventions in the intensive care unit (ICU) can improve patients' functional outcomes, yet systematic reviews identified discordant effects and poor reporting. We conducted a scoping review to determine the extent of ICU PR interventions and how they were reported and measured.

METHODS

We searched five databases from inception to December 2016 for prospective studies evaluating adult ICU PR interventions. Two independent reviewers screened titles, abstracts, and full texts for inclusion. We assessed completeness of reporting using the Consolidated Standards of Reporting Trials, Strengthening the Reporting of Observational Studies in Epidemiology, or Standards for Quality Improvement Reporting Excellence guidelines, as appropriate. For planned PR interventions, we evaluated reporting with the Consensus on Exercise Reporting Template (CERT) and assessed intervention and control groups separately. We calculated completeness of reporting scores for each study; scores represented the proportion of reported items. We compared reporting between groups using Kruskal-Wallis with Bonferroni corrections and t tests, α = 0.05.

RESULTS

We screened 61,774 unique citations, reviewed 1429 full-text publications, and included 117: 39 randomized trials, 30 case series, 9 two-group comparison, 14 before-after, and 25 cohort. Interventions included neuromuscular electrical stimulation (NMES) (14.5%), passive/active exercises (15.4%), cycling (6.8%), progressive mobility (32.5%), and multicomponent (29.9%). The median (first,third quartiles) study reporting score was 75.9% (62.5, 86.7) with no significant differences between reporting guidelines. Of 87 planned intervention studies, the median CERT score was 55.6%(44.7,75.0); cycling had the highest (85.0%(62.2,93.8)), and NMES and multicomponent the lowest (50.0% (39.5, 70.3) and 50.0% (41.5, 58.8), respectively) scores. Authors reported intervention groups better than controls (p < 0.001).

CONCLUSIONS

We identified important reporting deficiencies in ICU PR interventions, limiting clinical implementation and future trial development.

Exploring the Potential Effectiveness of Combining Optimal Nutrition With Electrical Stimulation to Maintain Muscle Health in Critical Illness: A Narrative Review

Muscle wasting occurs rapidly within days of an admission to the intensive care unit (ICU). Concomitant muscle weakness and impaired physical functioning can ensue, with lasting effects well after hospital discharge. Early physical rehabilitation is a promising intervention to minimize muscle weakness and physical dysfunction. However, there is an often a delay in commencing active functional exercises (such as sitting on the edge of bed, standing and mobilizing) due to sedation, patient alertness, and impaired ability to cooperate in the initial days of ICU admission. Therefore, there is high interest in being able to intervene early through nonvolitional exercise strategies such as electrical muscle stimulation (EMS). Muscle health characterized as the composite of muscle quantity, as well as functional and metabolic integrity, may be potentially maintained when optimal nutrition therapy is provided in complement with early physical rehabilitation in critically ill patients; however, the type, dosage, and timing of these interventions are unclear. This article explores the potential role of nutrition and EMS in maintaining muscle health in critical illness. Within this article, we will evaluate fundamental concepts of muscle wasting and evaluate the effects of EMS, as well as the effects of nutrition therapy on muscle health and the clinical and functional outcomes in critically ill patients. We will also highlight current research gaps in order to advance the field forward in this important area.

Physiotherapy in the neurotrauma intensive care unit: A scoping review

PURPOSE

This scoping review summarizes the literature on the safety and effectiveness of physiotherapy interventions in patients with neurological and/or traumatic injuries in the intensive care unit (ICU), identifies literature gaps and provides recommendations for future research.

MATERIALS AND METHODS

We searched five databases from inception to June 2, 2018. We included published retrospective studies, case studies, observation and randomized controlled trials describing physiotherapy interventions in ICU patients with neurotrauma injuries. Two reviewers reviewed the databases and independently screened English articles for eligibility. Data extracted included purpose, study design, population (s), outcome measures, interventions and results. Thematic analysis and descriptive numerical summaries are presented by intervention type.

RESULTS

12,846 titles were screened and 72 met the inclusion criteria. Most of the studies were observational studies (44 (61.1%)) and RCTs (14 (19.4%)). Early mobilization, electrical stimulation, range of motion, and chest physiotherapy techniques were the most common interventions in the literature. Physiotherapy interventions were found to be safe with few adverse events.

CONCLUSIONS

Gaps in the literature suggest that future studies require assessment of long term functional outcomes and quality of life, examination of homogenous populations and more robust methodologies including clinical trials and larger samples.

Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease

BACKGROUND

In people with chronic obstructive pulmonary disease (COPD), the use of neuromuscular electrostimulation (NMES) either alone, or together with conventional exercise training, might improve the condition of the peripheral muscles, increase exercise capacity and functional performance, reduce symptoms and improve health-related quality of life (HRQoL).

OBJECTIVES

To determine the effects of NMES, applied in isolation or concurrently with conventional exercise training to one or more peripheral muscles, on peripheral muscle force and endurance, muscle size, exercise capacity, functional performance, symptoms, HRQoL and adverse events in people with COPD.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register, the Physiotherapy Evidence Database, clinical trial registries and conference abstracts on 14 March 2018.

SELECTION CRITERIA

Randomised controlled trials that recruited adults with COPD if they had compared outcomes between a group that received NMES and a group that received usual care or compared outcomes between a group that received NMES plus conventional exercise training and a group that participated in conventional exercise training alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias using the Cochrane 'Risk of bias' tool. We expressed continuous data as either the standardised mean difference (SMD) or mean difference (MD) with the corresponding 95% confidence interval (CI). We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

Nineteen studies met the inclusion criteria of which 16 contributed data on 267 participants with COPD (mean age 56 to 76 years and 67% were men). Of these 16 studies, seven explored the effect of NMES versus usual care and nine explored the effect of NMES plus conventional exercise training versus conventional exercise training alone. Six studies utilised sham stimulation in the control group. When applied in isolation, NMES produced an increase in peripheral muscle force (SMD 0.34, 95% CI 0.02 to 0.65; low-quality evidence) and quadriceps endurance (SMD 1.36, 95% CI 0.59 to 2.12; low-quality evidence) but the effect on thigh muscle size was unclear (MD 0.25, 95% CI -0.11 to 0.61; low-quality evidence). There were increases in six-minute walk distance (6MWD) (MD 39.26 m, 95% CI 16.31 to 62.22; low-quality evidence) and time to symptom limitation exercising at a submaximal intensity (MD 3.62 minutes, 95% CI 2.33 to 4.91). There was a reduction in the severity of leg fatigue on completion of an exercise test (MD -1.12 units, 95% CI -1.81 to -0.43). The increase in peak rate of oxygen uptake (VO_2peak) was of borderline significance (MD 0.10 L/minute, 95% CI 0.00 to 0.19).For NMES with conventional exercise training, there was an uncertain effect on peripheral muscle force (SMD 0.47, 95% CI -0.10 to 1.04; very low-quality evidence) and there were insufficient studies to undertake a meta-analysis on the effect on quadriceps endurance or thigh muscle size. However, there was an increase in 6MWD in favour of NMES combined with conventional exercise training (MD 25.87 m, 95% CI 1.06 to 50.69; very low-quality evidence). In people admitted to either in an intensive care unit or a respiratory high dependency centre, NMES combined with conventional exercise reduced the time taken for participants to first sit out of bed by 4.98 days (95% CI -8.55 to -1.41; very low-quality evidence), although the statistical heterogeneity for this analysis was high (I² = 60%). For both types of studies (i.e. NMES versus usual care and NMES with conventional exercise training versus conventional exercise training alone), there was no risk difference for mortality or minor adverse events in participants who received NMES.

AUTHORS' CONCLUSIONS

NMES, when applied in isolation, increased quadriceps force and endurance, 6MWD and time to symptom limitation exercising at a submaximal intensity, and reduced the severity of leg fatigue on completion of exercise testing. It may increase VO_2peak, but the true effect on this outcome measure could be trivial. However, the quality of evidence was low or very low due to risk of bias within the studies, imprecision of the estimates, small number of studies and inconsistency between the studies. Although there were no additional gains in quadriceps force with NMES plus conventional exercise training, there was evidence of an increase in 6MWD. Further, in people who were the most debilitated, the addition of NMES may have accelerated the achievement of a functional milestone, that is, the first time someone sits out of bed.

Neuromuscular Electrical Stimulation for Treatment of Muscle Impairment: Critical Review and Recommendations for Clinical Practice

Purpose: In response to requests from physiotherapists for guidance on optimal stimulation of muscle using neuromuscular electrical stimulation (NMES), a review, synthesis, and extraction of key data from the literature was undertaken by six Canadian physical therapy (PT) educators, clinicians, and researchers in the field of electrophysical agents. The objective was to identify commonly treated conditions for which there was a substantial body of literature from which to draw conclusions regarding the effectiveness of NMES. Included studies had to apply NMES with visible and tetanic muscle contractions. Method: Four electronic databases (CINAHL, Embase, PUBMED, and SCOPUS) were searched for relevant literature published between database inceptions until May 2015. Additional articles were identified from bibliographies of the systematic reviews and from personal collections. Results: The extracted data were synthesized using a consensus process among the authors to provide recommendations for optimal stimulation parameters and application techniques to address muscle impairments associated with the following conditions: stroke (upper or lower extremity; both acute and chronic), anterior cruciate ligament reconstruction, patellofemoral pain syndrome, knee osteoarthritis, and total knee arthroplasty as well as critical illness and advanced disease states. Summaries of key details from each study incorporated into the review were also developed. The final sections of the article outline the recommended terminology for describing practice using electrical currents and provide tips for safe and effective clinical practice using NMES. Conclusion: This article provides physiotherapists with a resource to enable evidence-informed, effective use of NMES for PT practice.

Interventional strategies to combat muscle disuse atrophy in humans: focus on neuromuscular electrical stimulation and dietary protein

Numerous situations, such as the recovery from illness or rehabilitation after injury, necessitate a period of muscle disuse in otherwise healthy individuals. Even a few days of immobilization or bed rest can lead to substantial loss of skeletal muscle tissue and compromise metabolic health. The decline in muscle mass is attributed largely to a decline in postabsorptive and postprandial muscle protein synthesis rates. Reintroduction of some level of muscle contraction by the application of neuromuscular electrical stimulation (NMES) can augment both postabsorptive and postprandial muscle protein synthesis rates and, as such, prevent or attenuate muscle loss during short-term disuse in various clinical populations. Whereas maintenance of habitual dietary protein consumption is a prerequisite for muscle mass maintenance, supplementing dietary protein above habitual intake levels does not prevent muscle loss during disuse in otherwise healthy humans. Combining the anabolic properties of physical activity (or surrogates) with appropriate nutritional support likely further increases the capacity to preserve skeletal muscle mass during a period of disuse. Therefore, effective interventional strategies to prevent or alleviate muscle disuse atrophy should include both exercise (mimetics) and appropriate nutritional support.

Physiotherapy in the intensive care unit: an evidence-based, expert driven, practical statement and rehabilitation recommendations

OBJECTIVE

To develop evidence-based recommendations for effective and safe diagnostic assessment and intervention strategies for the physiotherapy treatment of patients in intensive care units.

METHODS

We used the EBRO method, as recommended by the 'Dutch Evidence Based Guideline Development Platform' to develop an 'evidence statement for physiotherapy in the intensive care unit'. This method consists of the identification of clinically relevant questions, followed by a systematic literature search, and summary of the evidence with final recommendations being moderated by feedback from experts.

RESULTS

Three relevant clinical domains were identified by experts: criteria to initiate treatment; measures to assess patients; evidence for effectiveness of treatments. In a systematic literature search, 129 relevant studies were identified and assessed for methodological quality and classified according to the level of evidence. The final evidence statement consisted of recommendations on eight absolute and four relative contra-indications to mobilization; a core set of nine specific instruments to assess impairments and activity restrictions; and six passive and four active effective interventions, with advice on (a) physiological measures to observe during treatment (with stopping criteria) and (b) what to record after the treatment.

CONCLUSIONS

These recommendations form a protocol for treating people in an intensive care unit, based on best available evidence in mid-2014.

Early rehabilitation using a passive cycle ergometer on muscle morphology in mechanically ventilated critically ill patients in the Intensive Care Unit (MoVe-ICU study): study protocol for a randomized controlled trial

BACKGROUND

Patients in Intensive Care Units (ICU) are often exposed to prolonged immobilization which, in turn, plays an important role in neuromuscular complications. Exercise with a cycle ergometer is a treatment option that can be used to improve the rehabilitation of patients on mechanical ventilation (MV) in order to minimize the harmful effects of immobility.

METHODS/DESIGN

A single-blind randomized controlled trial (the MoVe ICU study) will be conducted to evaluate and compare the effects of early rehabilitation using a bedside cycle ergometer with conventional physical therapy on the muscle morphology of the knee extensors and diaphragm in critical ill patients receiving MV. A total of 28 adult patients will be recruited for this study from among those admitted to the intensive care department at the Hospital de Clínicas de Porto Alegre. Eligible patients will be treated with MV from a period of 24 to 48 h, will have spent maximum of 1 week in hospital and will not exhibit any characteristics restricting lower extremity mobility. These subjects will be randomized to receive either conventional physiotherapy or conventional physiotherapy with an additional cycle ergometer intervention. The intervention will be administered passively for 20 min, at 20 revolutions per minute (rpm), once per day, 7 days a week, throughout the time the patients remain on MV. Outcomes will be cross-sectional quadriceps thickness, length of fascicle, pennation angle of fascicles, thickness of vastus lateralis muscle, diaphragm thickness and excursion of critical ICU patients on MV measured with ultrasound.

DISCUSSION

The MoVe-ICU study will be the first randomized controlled trial to test the hypothesis that early rehabilitation with a passive cycle ergometer can preserve the morphology of knee extensors and diaphragm in critical patients on MV in ICUs.

TRIAL REGISTRATION

NCT02300662 (25 November 2014).

The Sick and the Weak: Neuropathies/Myopathies in the Critically Ill

Critical illness polyneuropathies (CIP) and myopathies (CIM) are common complications of critical illness. Several weakness syndromes are summarized under the term intensive care unit-acquired weakness (ICUAW). We propose a classification of different ICUAW forms (CIM, CIP, sepsis-induced, steroid-denervation myopathy) and pathophysiological mechanisms from clinical and animal model data. Triggers include sepsis, mechanical ventilation, muscle unloading, steroid treatment, or denervation. Some ICUAW forms require stringent diagnostic features; CIM is marked by membrane hypoexcitability, severe atrophy, preferential myosin loss, ultrastructural alterations, and inadequate autophagy activation while myopathies in pure sepsis do not reproduce marked myosin loss. Reduced membrane excitability results from depolarization and ion channel dysfunction. Mitochondrial dysfunction contributes to energy-dependent processes. Ubiquitin proteasome and calpain activation trigger muscle proteolysis and atrophy while protein synthesis is impaired. Myosin loss is more pronounced than actin loss in CIM. Protein quality control is altered by inadequate autophagy. Ca(2+) dysregulation is present through altered Ca(2+) homeostasis. We highlight clinical hallmarks, trigger factors, and potential mechanisms from human studies and animal models that allow separation of risk factors that may trigger distinct mechanisms contributing to weakness. During critical illness, altered inflammatory (cytokines) and metabolic pathways deteriorate muscle function. ICUAW prevention/treatment is limited, e.g., tight glycemic control, delaying nutrition, and early mobilization. Future challenges include identification of primary/secondary events during the time course of critical illness, the interplay between membrane excitability, bioenergetic failure and differential proteolysis, and finding new therapeutic targets by help of tailored animal models.

Physical rehabilitation for critical illness myopathy and neuropathy

BACKGROUND

Intensive care unit (ICU) acquired or generalised weakness due to critical illness myopathy (CIM) and polyneuropathy (CIP) are major causes of chronically impaired motor function that can affect activities of daily living and quality of life. Physical rehabilitation of those affected might help to improve activities of daily living.

OBJECTIVES

Our primary objective was to assess the effects of physical rehabilitation therapies and interventions for people with CIP and CIM in improving activities of daily living such as walking, bathing, dressing and eating. Secondary objectives were to assess effects on muscle strength and quality of life, and to assess adverse effects of physical rehabilitation.

SEARCH METHODS

On 16 July 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register and on 14 July 2014 we searched CENTRAL, MEDLINE, EMBASE and CINAHL Plus. In July 2014, we searched the Physiotherapy Evidence Database (PEDro, http://www.pedro.org.au/) and three trials registries for ongoing trials and further data about included studies. There were no language restrictions. We also handsearched relevant conference proceedings and screened reference lists to identify further trials.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs), quasi-RCTs and randomised controlled cross-over trials of any rehabilitation intervention in people with acquired weakness syndrome due to CIP/CIM.

DATA COLLECTION AND ANALYSIS

We would have extracted data, assessed the risk of bias and classified the quality of evidence for outcomes in duplicate, according to the standard procedures of The Cochrane Collaboration. Outcome data collection would have been for activities of daily living (for example, mobility, walking, transfers and self care). Secondary outcomes included muscle strength, quality of life and adverse events.

MAIN RESULTS

The search strategy retrieved 3587 references. After examination of titles and abstracts, we retrieved the full text of 24 potentially relevant studies. None of these studies met the inclusion criteria of our review. No data were suitable to be included in a meta-analysis.

AUTHORS' CONCLUSIONS

There are no published RCTs or quasi-RCTs that examine whether physical rehabilitation interventions improve activities of daily living for people with CIP and CIM. Large RCTs, which are feasible, need to be conducted to explore the role of physical rehabilitation interventions for people with CIP and CIM.

Neuromuscular electrical stimulation prevents muscle wasting in critically ill comatose patients

Fully sedated patients, being treated in the intensive care unit (ICU), experience substantial skeletal muscle loss. Consequently, survival rate is reduced and full recovery after awakening is compromised. Neuromuscular electrical stimulation (NMES) represents an effective method to stimulate muscle protein synthesis and alleviate muscle disuse atrophy in healthy subjects. We investigated the efficacy of twice-daily NMES to alleviate muscle loss in six fully sedated ICU patients admitted for acute critical illness [n=3 males, n=3 females; age 63 ± 6 y; APACHE II (Acute Physiology and Chronic Health Evaluation II) disease-severity-score: 29 ± 2]. One leg was subjected to twice-daily NMES of the quadriceps muscle for a period of 7 ± 1 day whereas the other leg acted as a non-stimulated control (CON). Directly before the first and on the morning after the final NMES session, quadriceps muscle biopsies were collected from both legs to assess muscle fibre-type-specific cross-sectional area (CSA). Furthermore, phosphorylation status of the key proteins involved in the regulation of muscle protein synthesis was assessed and mRNA expression of selected genes was measured. In the CON leg, type 1 and type 2 muscle-fibre-CSA decreased by 16 ± 9% and 24 ± 7% respectively (P<0.05). No muscle atrophy was observed in the stimulated leg. NMES increased mammalian target of rapamycin (mTOR) phosphorylation by 19 ± 5% when compared with baseline (P<0.05), with no changes in the CON leg. Furthermore, mRNA expression of key genes involved in muscle protein breakdown either declined [forkhead box protein O1 (FOXO1); P<0.05] or remained unchanged [muscle atrophy F-box (MAFBx) and muscle RING-finger protein-1 (MuRF1)], with no differences between the legs. In conclusion, NMES represents an effective and feasible interventional strategy to prevent skeletal muscle atrophy in critically ill comatose patients.

Muscle atrophy in intensive care unit patients

Introduction:

The muscle atrophy is one of the most important and frequent problems observed in patients in Intensive Care Units. The term describes the disorder in the structure and in the function of the muscle while incidence rates range from 25-90 % in patients with prolonged hospitalization.

Purpose:

This is a review containing all data related to the issue of muscle atrophy and is especially referred to its causes and risk factors. The importance of early diagnosis and early mobilization are also highlighted in the study.

Material and methods:

a literature review was performed on valid databases such as Scopus, PubMed, Cinhal for the period 2000-2013 in English language. The following keywords were used: loss of muscle mass, ICU patients, immobilization, bed rest.

Results:

From the review is concluded that bed rest and immobilization in order to reduce total energy costs, are the main causes for the appearance of the problem. The results of the reduction of the muscle mass mainly affect the musculoskeletal, cardiovascular and respiratory system. The administration of the cortisone, the immobility, the sepsis and hyperglycemia are included in the risk factors. The prevention is the primary therapeutic agent and this is achieved due to the early mobilization of the patients, the use of neuromuscular electrical stimulation and the avoidance of exposure to risk factors.

Conclusions:

The prevention of muscle atrophy is a primary goal of treatment for the patients in the ICU, because it reduces the incidence of the disease, reduces the time spent in ICU and finally improves the quality of patients’ life.

An evaluation of neuromuscular electrical stimulation in critical care using the ICF framework: a systematic review and meta-analysis

OBJECTIVE

To review, in conformance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the totality of evidence for the use of neuromuscular electrical stimulation (NMES) in the critical care setting, when compared with usual care, under all domains of the World Health Organisation, International Classification of Functioning, Disability and Health (ICF) framework.

DATA SOURCE

Six electronic databases were searched: PubMed, Embase, Web of Knowledge, Cumulative Index to Nursing and Allied Health Literature, The Cochrane Library and the Physiotherapy Evidence Database (PEDro) (1945-2014). Limits of the English language and human studies were applied.

STUDY SELECTION

Trials investigating the effect of NMES in critical care adult patients were included. One reviewer excluded articles by title. Two reviewers excluded remaining articles by abstract and full text. One reviewer extracted data under a standardised form. Two reviewers assessed methodological quality using the Cochrane Risk of Bias Tool and the Newcastle Ottawa Scale.

RESULTS

Twelve full-text articles, eleven randomised controlled trials (RCTs) and one case-control trial indicated the potential of NMES to preserve muscle mass and joint range of motion, improve outcomes of ventilation, and reduce activity limitations. Meta-analysis from three RCTs supported NMES to preserve muscle strength using a fixed-effects model [n = 146; standardised mean difference 0.93 (0.51, 1.35) P = 0.0002]; however, significant heterogeneity was recorded. No outcomes evaluated the effect on participation restrictions.

CONCLUSION

NMES, as an adjunct to current rehabilitation practices in critically ill patients, may maintain muscle strength. However, high-quality studies with longer follow-up periods and standardised outcome measures across all domains of the ICF framework are required.

Functional electrical stimulation with cycling in the critically ill: a pilot case-matched control study

PURPOSE

The purpose was to determine (a) safety and feasibility of functional electrical stimulation (FES)-cycling and (b) compare FES-cycling to case-matched controls in terms of functional recovery and delirium outcomes.

MATERIALS AND METHODS

Sixteen adult intensive care unit patients with sepsis ventilated for more than 48 hours and in the intensive care unit for at least 4 days were included. Eight subjects underwent FES-cycling in addition to usual care and were compared to 8 case-matched control individuals. Primary outcomes were safety and feasibility of FES-cycling. Secondary outcomes were Physical Function in Intensive Care Test scored on awakening, time to reach functional milestones, and incidence and duration of delirium.

RESULTS

One minor adverse event was recorded. Sixty-nine out of total possible 95 FES sessions (73%) were completed. A visible or palpable contraction was present 80% of the time. There was an improvement in Physical Function in Intensive Care Test score of 3.9/10 points in the intervention cohort with faster recovery of functional milestones. There was also a shorter duration of delirium in the intervention cohort.

CONCLUSIONS

The delivery of FES-cycling is both safe and feasible. The preliminary findings suggest that FES-cycling may improve function and reduce delirium. Further research is required to confirm the findings of this study and evaluate the efficacy of FES-cycling.

Feasibility of neuromuscular electrical stimulation in critically ill patients

OBJECTIVE

Critically ill patients often develop intensive care unit-acquired weakness. Reduction in muscle mass and muscle strength occurs early after admission to the intensive care unit (ICU). Although early active muscle training could attenuate this intensive care unit-acquired weakness, in the early phase of critical illness, a large proportion of patients are unable to participate in any active mobilization. Neuromuscular electrical stimulation (NMES) could be an alternative strategy for muscle training. The aim of this study was to investigate the safety and feasibility of NMES in critically ill patients.

DESIGN

This is an observational study.

SETTING

The setting is in the medical and surgical ICUs of a tertiary referral university hospital.

PATIENTS

Fifty patients with a prognosticated prolonged stay of at least 6 days were included on day 3 to 5 of their ICU stay. Patients with preexisting neuromuscular disorders and patients with musculoskeletal conditions limiting quadriceps contraction were excluded.

INTERVENTION

Twenty-five minutes of simultaneous bilateral NMES of the quadriceps femoris muscle. This intervention was performed 5 days per week (Monday-Friday). Effective muscle stimulation was defined as a palpable and visible contraction (partial or full muscle bulk).

MEASUREMENTS

The following parameters, potentially affecting contraction upon NMES, were assessed: functional status before admission to the ICU (Barthel index), type and severity of illness (Acute Physiology And Chronic Health Evaluation II score and sepsis), treatments possibly influencing the muscle contraction (corticosteroids, vasopressors, inotropes, aminoglycosides, and neuromuscular blocking agents), level of consciousness (Glasgow Coma Scale, score on 5 standardized questions evaluating awakening, and sedation agitation scale), characteristics of stimulation (intensity of the NMES, number of sessions per patient, and edema), and neuromuscular electrophysiologic characteristics. Changes in heart rate, blood pressure, oxygen saturation, respiratory rate, and skin reactions were registered to assess the safety of the technique.

RESULTS

In 50% of the patients, an adequate quadriceps contraction was obtained in at least 75% of the NMES sessions. Univariate analysis showed that lower limb edema (P<.001), sepsis (P=.008), admission to the medical ICU (P=.041), and treatment with vasopressors (P=.011) were associated with impaired quadriceps contraction. A backward multivariate analysis identified presence of sepsis, lower limb edema, and use of vasopressors as independent predictors of impaired quadriceps contraction (R2=59.5%). Patients responded better to NMES in the beginning of their ICU stay in comparison with after 1 week of ICU stay. There was no change in any of the safety end points with NMES.

CONCLUSIONS

Critically ill patients having sepsis, edema, or receiving vasopressors were less likely to respond to NMES with an adequate quadriceps contraction. Neuromuscular electrical stimulation is a safe intervention to be administered in the ICU.

Electrical Muscle Stimulation in the Intensive Care Unit: An Integrative Review

Following a period of critical illness, physical function and health-related quality of life are slow to recover, both in the short and long term. Muscle wasting and weakness during the intensive care unit (ICU) admission is a recognised contributory factor. Enhanced rehabilitation programmes are advocated to improve outcomes, and electrical muscle stimulation (EMS) has been recommended during the early critical illness trajectory. This technique is fairly new to the ICU, and limited efficacy data exists for its use in this setting. This integrative review will examine published and on-going ICU studies with the purpose of reporting on the characteristics of EMS study participants; content of EMS treatment protocols; safety of EMS in the ICU setting; effects on EMS on muscle wasting; effects of EMS on muscle strength; and future research.

Electrical muscle stimulation in the intensive care setting: a systematic review

CONTEXT

The role of electrical muscle stimulation in intensive care has not previously been systematically reviewed.

OBJECTIVES

To identify, evaluate, and synthesize the evidence examining the effectiveness and the safety of electrical muscle stimulation in the intensive care, and the optimal intervention variables.

DATA SOURCES

A systematic review of articles using eight electronic databases (Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Excerpta Medica Database, Expanded Academic ASAP, MEDLINE, Physiotherapy Evidence Database, PubMed, and Scopus) personal files were searched, and cross-referencing was undertaken.

ELIGIBILITY CRITERIA

Quantitative studies published in English, assessing electrical muscle stimulation in intensive care, were included.

DATA EXTRACTION AND DATA SYNTHESIS

One reviewer extracted data using a standardized form, which were cross-checked by a second reviewer. Quality appraisal was undertaken by two independent reviewers using the Physiotherapy Evidence Database and Newcastle-Ottawa scales, and the National Health and Medical Research Council Hierarchy of Evidence Scale. Preferred Reporting Items for Systematic Reviews guidelines were followed.

RESULTS

Nine studies on six individual patient groups of 136 participants were included. Eight were randomized controlled trials, with four studies reporting on the same cohort of participants. Electrical muscle stimulation appears to preserve muscle mass and strength in long-stay participants and in those with less acuity. No such benefits were observed when commenced prior to 7 days or in patients with high acuity. One adverse event was reported. Optimal training variables and safety of the intervention require further investigation.

CONCLUSIONS

Electrical muscle stimulation is a promising intervention; however, there is conflicting evidence for its effectiveness when administered acutely. Outcomes measured are heterogeneous with small sample sizes.

A review of the efficacy of neuromuscular electrical stimulation in critically ill patients

BACKGROUND

Muscle wasting in critical illness has been identified as a major clinical concern which can lead to persistent muscle weakness, impede recovery and limit physical function and quality of life in survivors. Neuromuscular electrical stimulation (NMES) has been suggested as an alternative to active exercise in critically ill patients.

OBJECTIVES

To evaluate the efficacy of NMES in critically ill patients by evaluating the research literature.

METHODS

Structured database searches of the Cochrane Library, Ovid (Medline), CINHAL, Scopus and PEDro were completed.

RESULTS

Eight papers were retrieved and methodological quality evaluated using the Critical Appraisal and Skills Program tool. The NMES protocols, outcomes and findings were analysed and, given the methodological heterogeneity, the study findings were synthesised as a narrative. Analysis showed minimal adverse effects in the use of NMES and some potential benefits of NMES on preservation of muscle strength, decreased duration of mechanical ventilation and shorter Intensive Care Unit (ICU) length of stay.

CONCLUSIONS

Evidence of the clinical benefits of NMES in the ICU is inconclusive and provides minimal guidance for use in clinical practice. There is a need for further research in this area.

Long-term TENS treatment decreases cortical motor representation in multiple sclerosis

This study investigated the effects of a long-term transcutaneous electrical nerve stimulation (TENS) treatment on cortical motor representation in patients with multiple sclerosis (MS). In this double-blind crossover design, patients received either TENS or sham stimulation for 3 weeks (1h per day) on the median nerve region of the most impaired hand, followed by the other stimulation condition after a washout period of 6 months. Cortical motor representation was mapped using transcranial magnetic stimulation (TMS) at the baseline and after the 3-week stimulation protocol. Our results revealed that 3 weeks of daily stimulation with TENS significantly decreased the cortical motor representation of the stimulated muscle in MS patients. Although the mechanisms underlying this decrease remain unclear, our findings indicate that TENS has the ability to induce long-term reorganization in the motor cortex of MS patients.

Neuromuscular electrical stimulation for preventing skeletal-muscle weakness and wasting in critically ill patients: a systematic review

BACKGROUND

Neuromuscular electrical stimulation (NMES) therapy may be useful in early musculoskeletal rehabilitation during acute critical illness. The objective of this systematic review was to evaluate the effectiveness of NMES for preventing skeletal-muscle weakness and wasting in critically ill patients, in comparison with usual care.

METHODS

We searched PubMed, CENTRAL, CINAHL, Web of Science, and PEDro to identify randomized controlled trials exploring the effect of NMES in critically ill patients, which had a well-defined NMES protocol, provided outcomes related to skeletal-muscle strength and/or mass, and for which full text was available. Two independent reviewers extracted data on muscle-related outcomes (strength and mass), and participant and intervention characteristics, and assessed the methodological quality of the studies. Owing to the lack of means and standard deviations (SDs) in some studies, as well as the lack of baseline measurements in two studies, it was impossible to conduct a full meta-analysis. When means and SDs were provided, the effect sizes of individual outcomes were calculated, and otherwise, a qualitative analysis was performed.

RESULTS

The search yielded 8 eligible studies involving 172 patients. The methodological quality of the studies was moderate to high. Five studies reported an increase in strength or better preservation of strength with NMES, with one study having a large effect size. Two studies found better preservation of muscle mass with NMES, with small to moderate effect sizes, while no significant benefits were found in two other studies.

CONCLUSIONS

NMES added to usual care proved to be more effective than usual care alone for preventing skeletal-muscle weakness in critically ill patients. However, there is inconclusive evidence for its benefit in prevention of muscle wasting.

Neuromuscular electrical stimulation for intensive care unit-acquired weakness: protocol and methodological implications for a randomized, sham-controlled, phase II trial

BACKGROUND

As the population ages and critical care advances, a growing number of survivors of critical illness will be at risk for intensive care unit (ICU)-acquired weakness. Bed rest, which is common in the ICU, causes adverse effects, including muscle weakness. Consequently, patients need ICU-based interventions focused on the muscular system. Although emerging evidence supports the benefits of early rehabilitation during mechanical ventilation, additional therapies may be beneficial. Neuromuscular electrical stimulation (NMES), which can provide some muscular activity even very early during critical illness, is a promising modality for patients in the ICU.

OBJECTIVE

The objectives of this article are to discuss the implications of bed rest for patients with critical illness, summarize recent studies of early rehabilitation and NMES in the ICU, and describe a protocol for a randomized, phase II pilot study of NMES in patients receiving mechanical ventilation.

DESIGN

The study was a randomized, sham-controlled, concealed, phase II pilot study with caregivers and outcome assessors blinded to the treatment allocation.

SETTING

The study setting will be a medical ICU.

PARTICIPANTS

The study participants will be patients who are receiving mechanical ventilation for 1 day or more, who are expected to stay in the ICU for an additional 2 days or more, and who meet no exclusion criteria.

INTERVENTION

The intervention will be NMES (versus a sham [control] intervention) applied to the quadriceps, tibialis anterior, and gastrocnemius muscles for 60 minutes per day.

MEASUREMENTS

Lower-extremity muscle strength at hospital discharge will be the primary outcome measure.

LIMITATIONS

Muscle strength is a surrogate measure, not a patient-centered outcome. The assessments will not include laboratory, genetic, or histological measures aimed at a mechanistic understanding of NMES. The optimal duration or dose of NMES is unclear.

CONCLUSIONS

If NMES is beneficial, the results of the study will help advance research aimed at reducing the burden of muscular weakness and physical disability in survivors of critical illness.