Effects of intermittent electrical stimulations on muscle catabolism in intensive care patients

Bioelectric medicine: unveiling the therapeutic potential of micro-current stimulation

Bioelectric medicine (BEM) refers to the use of electrical signals to modulate the electrical activity of cells and tissues in the body for therapeutic purposes. In this review, we particularly focused on the microcurrent stimulation (MCS), because, this can take place at the cellular level with sub-sensory application unlike other stimuli. These extremely low-level currents mimic the body's natural electrical activity and are believed to promote various physiological processes. To date, MCS has limited use in the field of BEM with applications in several therapeutic purposes. However, recent studies provide hopeful signs that MCS is more scalable and widely applicable than what has been used so far. Therefore, this review delves into the landscape of MCS, shedding light on the multifaceted applications and untapped potential of MCS in the realm of healthcare. Particularly, we summarized the hierarchical mediation from cell to whole body responses by MCS including its physiological applications. Our final objective of this review is to contribute to the growing body of literature that unveils the captivating potential of BEM, with MCS poised at the intersection of technological innovation and the intricacies of the human body.

Skeletal muscle adaptation to indirect electrical stimulation: divergence between microvascular and metabolic adaptations

NEW FINDINGS

What is the central question of this study? Can we manipulate muscle recruitment to differentially enhance skeletal muscle fatigue resistance? What is the main finding and its importance? Through manipulation of muscle activation patterns, it is possible to promote distinct microvascular growth. Enhancement of fatigue resistance is closely associated with the distribution of the capillaries within the muscle, not necessarily with quantity. Additionally, at the acute stages of remodelling in response to indirect electrical stimulation, the improvement in fatigue resistance appears to be primarily driven by vascular remodelling, with metabolic adaptation of secondary importance.

ABSTRACT

Exercise involves a complex interaction of factors influencing muscle performance, where variations in recruitment pattern (e.g., endurance vs. resistance training) may differentially modulate the local tissue environment (i.e., oxygenation, blood flow, fuel utilization). These exercise stimuli are potent drivers of vascular and metabolic change. However, their relative contribution to adaptive remodelling of skeletal muscle and subsequent performance is unclear. Using implantable devices, indirect electrical stimulation (ES) of locomotor muscles of rat at different pacing frequencies (4, 10 and 40 Hz) was used to differentially recruit hindlimb blood flow and modulate fuel utilization. After 7 days, ES promoted significant remodelling of microvascular composition, increasing capillary density in the cortex of the tibialis anterior by 73%, 110% and 55% for the 4 Hz, 10 and 40 Hz groups, respectively. Additionally, there was remodelling of the whole muscle metabolome, including significantly elevated amino acid turnover, with muscle kynurenic acid levels doubled by pacing at 10 Hz (P < 0.05). Interestingly, the fatigue index of skeletal muscle was only significantly elevated in 10 Hz (58% increase) and 40 Hz (73% increase) ES groups, apparently linked to improved capillary distribution. These data demonstrate that manipulation of muscle recruitment pattern may be used to differentially expand the capillary network prior to altering the metabolome, emphasising the importance of local capillary supply in promoting exercise tolerance.

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.

Effectiveness of contralaterally controlled functional electrical stimulation vs. neuromuscular electrical stimulation for recovery of lower extremity function in patients with subacute stroke: A randomized controlled trial

Objective

This study aimed to compare the efficacy of contralaterally controlled functional electrical stimulation (CCFES) vs. neuromuscular electrical stimulation (NMES) for motor recovery of the lower extremity in patients with subacute stroke.

Materials and methods

Seventy patients within 6 months post-stroke were randomly assigned to the CCFES group (n = 35) and the NMES group (n = 35). Both groups underwent routine rehabilitation plus 20-min electrical stimulation (CCFES or NMES) on ankle dorsiflexion muscles per day, 5 days a week, for 3 weeks. Ankle AROM (dorsiflexion), Fugl-Meyer assessment-lower extremity (FMA-LE), Barthel Index (BI), Functional Ambulation Category scale (FAC), 10-meter walking test, and surface electromyography (sEMG) were assessed at the baseline and at the end of the intervention.

Result

Ten patients did not complete the study (five in CCFES and five in NMES), so only 60 patients were analyzed in the end. After the 3-week intervention, FMA-LE, BI, Ankle AROM (dorsiflexion), and FAC increased in both groups (p < 0.05). Patients in the CCFES group showed significantly greater improvements only in the measurement of Fugl-Meyer assessment-lower extremity compared with the NMES group after treatment (p < 0.05). The improvement in sEMG response of tibialis anterior by CCFES was greater than NMES (p < 0.05).

Conclusion

Contralateral controlled functional electrical stimulation can effectively improve the motor function of the lower limbs better than conventional neuromuscular electrical stimulation in subacute patients after stroke, but the effect on improving the ability to walk, such as walking speed, was not good.

Clinical trial registration

http://www.chictr.org.cn/, identifier: ChiCTR2100045423.

Prolonged Weaning: S2k Guideline Published by the German Respiratory Society

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by respiratory muscle insufficiency and/or lung parenchymal disease; that is, when other treatments such as medication, oxygen administration, secretion management, continuous positive airway pressure (CPAP), or nasal high-flow therapy have failed. MV is required for maintaining gas exchange and allows more time to curatively treat the underlying cause of respiratory failure. In the majority of ventilated patients, liberation or "weaning" from MV is routine, without the occurrence of any major problems. However, approximately 20% of patients require ongoing MV, despite amelioration of the conditions that precipitated the need for it in the first place. Approximately 40-50% of the time spent on MV is required to liberate the patient from the ventilator, a process called "weaning". In addition to acute respiratory failure, numerous factors can influence the duration and success rate of the weaning process; these include age, comorbidities, and conditions and complications acquired during the ICU stay. According to international consensus, "prolonged weaning" is defined as the weaning process in patients who have failed at least 3 weaning attempts, or require more than 7 days of weaning after the first spontaneous breathing trial (SBT). Given that prolonged weaning is a complex process, an interdisciplinary approach is essential for it to be successful. In specialised weaning centres, approximately 50% of patients with initial weaning failure can be liberated from MV after prolonged weaning. However, the heterogeneity of patients undergoing prolonged weaning precludes the direct comparison of individual centres. Patients with persistent weaning failure either die during the weaning process, or are discharged back to their home or to a long-term care facility with ongoing MV. Urged by the growing importance of prolonged weaning, this Sk2 Guideline was first published in 2014 as an initiative of the German Respiratory Society (DGP), in conjunction with other scientific societies involved in prolonged weaning. The emergence of new research, clinical study findings and registry data, as well as the accumulation of experience in daily practice, have made the revision of this guideline necessary. The following topics are dealt with in the present guideline: Definitions, epidemiology, weaning categories, underlying pathophysiology, prevention of prolonged weaning, treatment strategies in prolonged weaning, the weaning unit, discharge from hospital on MV, and recommendations for end-of-life decisions. Special emphasis was placed on the following themes: (1) A new classification of patient sub-groups in prolonged weaning. (2) Important aspects of pulmonary rehabilitation and neurorehabilitation in prolonged weaning. (3) Infrastructure and process organisation in the care of patients in prolonged weaning based on a continuous treatment concept. (4) Changes in therapeutic goals and communication with relatives. Aspects of paediatric weaning are addressed separately within individual chapters. The main aim of the revised guideline was to summarize both current evidence and expert-based knowledge on the topic of "prolonged weaning", and to use this information as a foundation for formulating recommendations related to "prolonged weaning", not only in acute medicine but also in the field of chronic intensive care medicine. The following professionals served as important addressees for this guideline: intensivists, pulmonary medicine specialists, anaesthesiologists, internists, cardiologists, surgeons, neurologists, paediatricians, geriatricians, palliative care clinicians, rehabilitation physicians, intensive/chronic care nurses, physiotherapists, respiratory therapists, speech therapists, medical service of health insurance, and associated ventilator manufacturers.

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.

Safety of neuromuscular electrical stimulation among critically ill patients: systematic review

OBJECTIVE

To review the evidence on the safety of neuromuscular electrical stimulation when used in the intensive care unit.

METHODS

A systematic review was conducted; a literature search was performed of the MEDLINE (via PubMed), PEDro, Cochrane CENTRAL and EMBASE databases, and a further manual search was performed among the references cited in randomized studies. Randomized clinical trials that compared neuromuscular electrical stimulation to a control or placebo group in the intensive care unit and reporting on the technique safety in the outcomes were included. Hemodynamic variables and information on adverse effects were considered safety parameters. Articles were independently analyzed by two reviewers, and the data analysis was descriptive.

RESULTS

The initial search located 1,533 articles, from which only four randomized clinical trials were included. Two studies assessed safety based on hemodynamic variables, and only one study reported an increase in heart rate, respiratory rate and blood lactate, without clinical relevance. The other two studies assessed safety based on reported adverse effects. In one, 15% of patients described a prickling sensation, without any clinically relevant abnormalities. In the other, one patient suffered a superficial burn due to improper parameter configuration.

CONCLUSION

Neuromuscular electrical stimulation is safe for critically ill patients; however, it should be applied by duly trained professionals and with proper evidence-based parameters.

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.

Effect of neuromuscular stimulation and individualized rehabilitation on muscle strength in Intensive Care Unit survivors: A randomized trial

PURPOSE

Intensive Care Unit (ICU) survivors experience muscle weakness leading to restrictions in functional ability. Neuromuscular electrical stimulation (NMES) has been an alternative to exercise in critically ill patients. The aim of our study was to investigate its effects along with individualized rehabilitation on muscle strength of ICU survivors.

MATERIAL AND METHODS

Following ICU discharge, 128 patients (age: 53±16years) were randomly assigned to daily NMES sessions and individualized rehabilitation (NMES group) or to control group. Muscle strength was assessed by the Medical Research Council (MRC) score and hand grip at hospital discharge. Secondary outcomes were functional ability and hospital length of stay.

RESULTS

MRC, handgrip, functional status and hospital length of stay did not differ at hospital discharge between groups (p>0.05). ΔMRC% one and two weeks after ICU discharge tended to be higher in NMES group, while it was significant higher in NMES group of patients with ICU-acquired weakness at two weeks (p=0.05).

CONCLUSIONS

NMES and personalized physiotherapy in ICU survivors did not result in greater improvement of muscle strength and functional status at hospital discharge. However, in patients with ICU-aw NMES may be effective. The potential benefits of rehabilitation strategies should be explored in larger number of patients in future studies.

CLINICAL TRIAL REGISTRATION

www.Clinicaltrials.gov: NCT01717833.

Neuromuscular electrical stimulation may attenuate muscle proteolysis after cardiovascular surgery: A preliminary study

OBJECTIVE

To explore the efficacy of postoperative neuromuscular electrical stimulation (NMES) on muscle protein degradation and muscle weakness in patients after cardiovascular surgery.

METHODS

Sixty-one patients underwent NMES daily from postoperative days (PODs) 1 to 5 in addition to postoperative mobilization program (NMES group), and 41 patients underwent postoperative mobilization program only (non-NMES group). The primary outcome was the concentration of 3-methylhistidine (3-MH) in 24-hour urine corrected for urinary creatinine content (3-MH/Cre) from PODs 1 to 5. The secondary outcomes were knee extensor isometric strength (KEIS) and handgrip strength at POD 7.

RESULTS

Baseline characteristics such as age, sex, preoperative body mass index, hemoglobin, handgrip strength, KEIS, surgery type, cardiopulmonary bypass time, and immediate postoperative interleukin-6 were not different between the groups. Urinary 3-MH/Cre was increased significantly in both groups; however, urinary 3-MH/Cre in the NMES group peaked earlier compared with that in the non-NMES group. KEIS at POD 7 was significantly greater in the NMES group (median [interquartile range], 0.40 kg/weight [0.33-0.45] in the NMES group vs 0.23 kg/weight [0.15-0.36] in the non-NMES group; P < .01). Handgrip strength at POD 7 was also significantly greater in the NMES group (median [interquartile range], 32 kg [24.5-35.3] in the NMES group vs 24 kg [16.0-30.0] in the non-NMES group; P < .01).

CONCLUSIONS

This study demonstrated that NMES might attenuate skeletal muscle protein degradation and muscle weakness after cardiovascular surgery. A cause-effect relationship between NMES and functional preservation would be a future challenging issue.

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.

Critical illness polyneuropathy and myopathy: a systematic review

Critical illness polyneuropathy and critical illness myopathy are frequent complications of severe illness that involve sensorimotor axons and skeletal muscles, respectively. Clinically, they manifest as limb and respiratory muscle weakness. Critical illness polyneuropathy/myopathy in isolation or combination increases intensive care unit morbidity via the inability or difficulty in weaning these patients off mechanical ventilation. Many patients continue to suffer from decreased exercise capacity and compromised quality of life for months to years after the acute event. Substantial progress has been made lately in the understanding of the pathophysiology of critical illness polyneuropathy and myopathy. Clinical and ancillary test results should be carefully interpreted to differentiate critical illness polyneuropathy/myopathy from similar weaknesses in this patient population. The present review is aimed at providing the latest knowledge concerning the pathophysiology of critical illness polyneuropathy/myopathy along with relevant clinical, diagnostic, differentiating, and treatment information for this debilitating neurological disease.

Application and effects of neuromuscular electrical stimulation in critically ill patients: systematic review

OBJECTIVE

To investigate the applications and effects of neuromuscular electrical stimulation (NMES) in critically ill patients in ICU by means of a systematic review.

MATERIALS AND METHODS

Electronic searches were conducted in the databases Medline, CINAHL, Cochrane Central Register of Controlled Trials, Web of Science, Embase, ProQuest Health and Medical Complete, AMED, and PEDro. The PEDro score was used to assess the methodological quality of the eligible studies.

RESULTS

The search yielded a total of 9759 titles and nine articles satisfied the eligibility criteria. These studies showed that NMES can maintain or increase muscle mass, strength and volume, reduce time in mechanical ventilation and weaning time, and increase muscle degradation in critically ill patients in ICU. Two studies allowed a meta-analysis of the effects of NMES on quadriceps femoris strength and it showed a significant effect in favor of NMES in the Medical Research Council (MRC) Scale (standardized mean difference 0.77 points; p=0.02; 95% CI: 0.13-1.40).

CONCLUSIONS

The selected studies showed that NMES has good results when used for the maintenance of muscle mass and strength in critically ill patients in ICU. Future studies with high methodological quality should be conducted to provide more evidence for the use of NMES in an ICU setting.

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.

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

BACKGROUND

Critical illness polyneuropathy or myopathy (CIP/CIM) is a frequent complication in the intensive care unit (ICU) and is associated with prolonged mechanical ventilation, longer ICU stay and increased mortality. This is an interim update of a review first published in 2009 (Hermans 2009). It has been updated to October 2011, with further potentially eligible studies from a December 2013 search characterised as awaiting assessment.

OBJECTIVES

To systematically review the evidence from RCTs concerning the ability of any intervention to reduce the incidence of CIP or CIM in critically ill individuals.

SEARCH METHODS

On 4 October 2011, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, and EMBASE. We checked the bibliographies of identified trials and contacted trial authors and experts in the field. We carried out an additional search of these databases on 6 December 2013 to identify recent studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs), examining the effect of any intervention on the incidence of CIP/CIM in people admitted to adult medical or surgical ICUs. The primary outcome was the incidence of CIP/CIM in ICU, based on electrophysiological or clinical examination. Secondary outcomes included duration of mechanical ventilation, duration of ICU stay, death at 30 and 180 days after ICU admission and serious adverse events from the treatment regimens.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias in included studies.

MAIN RESULTS

We identified five trials that met our inclusion criteria. Two trials compared intensive insulin therapy (IIT) to conventional insulin therapy (CIT). IIT significantly reduced CIP/CIM in the screened (n = 825; risk ratio (RR) 0.65, 95% confidence interval (CI) 0.55 to 0.77) and total (n = 2748; RR 0.70, 95% CI 0.60 to 0.82) population randomised. IIT reduced duration of mechanical ventilation, ICU stay and 180-day mortality, but not 30-day mortality compared with CIT. Hypoglycaemia increased with IIT but did not cause early deaths.One trial compared corticosteroids with placebo (n = 180). The trial found no effect of treatment on CIP/CIM (RR 1.27, 95% CI 0.77 to 2.08), 180-day mortality, new infections, glycaemia at day seven, or episodes of pneumonia, but did show a reduction of new shock events.In the fourth trial, early physical therapy reduced CIP/CIM in 82/104 evaluable participants in ICU (RR 0.62. 95% CI 0.39 to 0.96). Statistical significance was lost when we performed a full intention-to-treat analysis (RR 0.81, 95% CI 0.60 to 1.08). Duration of mechanical ventilation but not ICU stay was significantly shorter in the intervention group. Hospital mortality was not affected but 30- and 180-day mortality results were not available. No adverse effects were noticed.The last trial found a reduced incidence of CIP/CIM in 52 evaluable participants out of a total of 140 who were randomised to electrical muscle stimulation (EMS) versus no stimulation (RR 0.32, 95% CI 0.10 to 1.01). These data were prone to bias due to imbalances between treatment groups in this subgroup of participants. After we imputed missing data and performed an intention-to-treat analysis, there was still no significant effect (RR 0.94, 95% CI 0.78 to 1.15). The investigators found no effect on duration of mechanical ventilation and noted no difference in ICU mortality, but did not report 30- and 180-day mortality.We updated the searches in December 2013 and identified nine potentially eligible studies that will be assessed for inclusion in the next update of the review.

AUTHORS' CONCLUSIONS

There is moderate quality evidence from two large trials that intensive insulin therapy reduces CIP/CIM, and high quality evidence that it reduces duration of mechanical ventilation, ICU stay and 180-day mortality, at the expense of hypoglycaemia. Consequences and prevention of hypoglycaemia need further study. There is moderate quality evidence which suggests no effect of corticosteroids on CIP/CIM and high quality evidence that steroids do not affect secondary outcomes, except for fewer new shock episodes. Moderate quality evidence suggests a potential benefit of early rehabilitation on CIP/CIM which is accompanied by a shorter duration of mechanical ventilation but without an effect on ICU stay. Very low quality evidence suggests no effect of EMS, although data are prone to bias. Strict diagnostic criteria for CIP/CIM are urgently needed for research purposes. Large RCTs need to be conducted to further explore the role of early rehabilitation and EMS and to develop new preventive strategies.

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

BACKGROUND

Critical illness polyneuropathy or myopathy (CIP/CIM) is a frequent complication in the intensive care unit (ICU) and is associated with prolonged mechanical ventilation, longer ICU stay and increased mortality. This is an interim update of a review first published in 2009 (Hermans 2009). It has been updated to October 2011, with further potentially eligible studies from a December 2013 search characterised as awaiting assessment.

OBJECTIVES

To systematically review the evidence from RCTs concerning the ability of any intervention to reduce the incidence of CIP or CIM in critically ill individuals.

SEARCH METHODS

On 4 October 2011, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, and EMBASE. We checked the bibliographies of identified trials and contacted trial authors and experts in the field. We carried out an additional search of these databases on 6 December 2013 to identify recent studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs), examining the effect of any intervention on the incidence of CIP/CIM in people admitted to adult medical or surgical ICUs. The primary outcome was the incidence of CIP/CIM in ICU, based on electrophysiological or clinical examination. Secondary outcomes included duration of mechanical ventilation, duration of ICU stay, death at 30 and 180 days after ICU admission and serious adverse events from the treatment regimens.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias in included studies.

MAIN RESULTS

We identified five trials that met our inclusion criteria. Two trials compared intensive insulin therapy (IIT) to conventional insulin therapy (CIT). IIT significantly reduced CIP/CIM in the screened (n = 825; risk ratio (RR) 0.65, 95% confidence interval (CI) 0.55 to 0.77) and total (n = 2748; RR 0.70, 95% CI 0.60 to 0.82) population randomised. IIT reduced duration of mechanical ventilation, ICU stay and 180-day mortality, but not 30-day mortality compared with CIT. Hypoglycaemia increased with IIT but did not cause early deaths.One trial compared corticosteroids with placebo (n = 180). The trial found no effect of treatment on CIP/CIM (RR 1.27, 95% CI 0.77 to 2.08), 180-day mortality, new infections, glycaemia at day seven, or episodes of pneumonia, but did show a reduction of new shock events.In the fourth trial, early physical therapy reduced CIP/CIM in 82/104 evaluable participants in ICU (RR 0.62. 95% CI 0.39 to 0.96). Statistical significance was lost when we performed a full intention-to-treat analysis (RR 0.81, 95% CI 0.60 to 1.08). Duration of mechanical ventilation but not ICU stay was significantly shorter in the intervention group. Hospital mortality was not affected but 30- and 180-day mortality results were not available. No adverse effects were noticed.The last trial found a reduced incidence of CIP/CIM in 52 evaluable participants out of a total of 140 who were randomised to electrical muscle stimulation (EMS) versus no stimulation (RR 0.32, 95% CI 0.10 to 1.01). These data were prone to bias due to imbalances between treatment groups in this subgroup of participants. After we imputed missing data and performed an intention-to-treat analysis, there was still no significant effect (RR 0.94, 95% CI 0.78 to 1.15). The investigators found no effect on duration of mechanical ventilation and noted no difference in ICU mortality, but did not report 30- and 180-day mortality.We updated the searches in December 2013 and identified nine potentially eligible studies that will be assessed for inclusion in the next update of the review.

AUTHORS' CONCLUSIONS

There is moderate quality evidence from two large trials that intensive insulin therapy reduces CIP/CIM, and high quality evidence that it reduces duration of mechanical ventilation, ICU stay and 180-day mortality, at the expense of hypoglycaemia. Consequences and prevention of hypoglycaemia need further study. There is moderate quality evidence which suggests no effect of corticosteroids on CIP/CIM and high quality evidence that steroids do not affect secondary outcomes, except for fewer new shock episodes. Moderate quality evidence suggests a potential benefit of early rehabilitation on CIP/CIM which is accompanied by a shorter duration of mechanical ventilation but without an effect on ICU stay. Very low quality evidence suggests no effect of EMS, although data are prone to bias. Strict diagnostic criteria for CIP/CIM are urgently needed for research purposes. Large RCTs need to be conducted to further explore the role of early rehabilitation and EMS and to develop new preventive strategies.

Myofibrillar protein overdegradation in overweight patients with chronic heart failure: the relationship to serum potassium levels

OBJECTIVES

Muscle release of the amino acid 3-methyl-histidine (3MH) is a sensitive index of myofibrillar protein overdegradation (MPO). We hypothesized that patients with chronic heart failure (CHF) could have increased muscle release of 3MH, which in turn reflects MPO, and that serum electrolyte sodium (Na(+)) and potassium (K(+)) levels may be associated with this 3MH muscle release.

METHODS

Thirty-one overweight outpatients (body mass index, 27 ± 4.4 kg/m(2); 22 men and 9 women; age, 56 ± 8.7 y) with clinically stable CHF were studied. After a 24-hour meat-free diet and overnight fasting, patients underwent blood sampling from a cannulated arm vein (V) and concomitantly from the arterial artery (A) to determine plasma 3MH levels and to calculate the A-V difference. Serum levels of Na(+) and K(+) in the venous blood were determined, and the Na(+)/K(+) ratio was calculated. Ten healthy subjects who were matched for gender, age, and body mass index served as controls and underwent the same protocol as the patients with CHF.

RESULTS

The patient group had higher arterial (P = 0.02) and venous (P = 0.005) 3MH levels but a similar A-V 3MH difference (P = 0.28) as compared with the controls. Within the CHF group, 67.7% of patients released 3MH, which resulted in a negative A-V value (P < 0.02 as compared with controls). In patients with CHF, the A-V 3MH difference correlated positively with the serum K(+) level (r = 0.62; P = 0.0002) and negatively with Na(+)/K(+) ratio (r = -0.55; P = 0.002). No association was found between the A-V 3MH difference and the Na(+) level.

CONCLUSIONS

The study demonstrated the existence of MPO in resting overweight patients with CHF, thereby suggesting that low serum levels of K(+) may contribute to MPO.

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.

Early Physical Rehabilitation in the ICU: A Review for the Neurohospitalist

Advances in critical care have resulted in improved intensive care unit (ICU) mortality. However, improved ICU survival has resulted in a growing number of ICU survivors living with long-term sequelae of critical illness, such as impaired physical function and quality of life (QOL). In addition to critical illness, prolonged bed rest and immobility may lead to severe physical deconditioning and loss of muscle mass and muscle weakness. ICU-acquired weakness is associated with increased duration of mechanical ventilation and weaning, longer ICU and hospital stay, and increased mortality. These physical impairments may last for years after ICU discharge. Early Physical Medicine and Rehabilitation (PM&R) interventions in the ICU may attenuate or prevent the weakness and physical impairments occurring during critical illness. This article reviews the evidence regarding safety, feasibility, barriers, and benefits of early PM&R interventions in ICU patients and discusses the limited existing data on early PM&R in the neurological ICU and future directions for early PM&R in the ICU.

Physical therapy for the critically ill in the ICU: a systematic review and meta-analysis

OBJECTIVE

The purpose of this systematic review was to review the evidence base for exercise in critically ill patients.

DATA SOURCES AND STUDY SELECTION

Using keywords critical care and physical therapy and related synonyms, randomized controlled trials, meta-analyses, and systematic reviews were identified through electronic database searches and citation tracking. Clinical trials with outcomes of mortality, length of hospital and ICU stay, physical function and quality of life, muscle strength, and ventilator-free days were included.

DATA EXTRACTION AND SYNTHESIS

Two reviewers abstracted data and assessed quality independently. Effect sizes and 95% confidence intervals were calculated. From 3,126 screened abstracts, 10 randomized controlled trials and five reviews were found. The mean Physiotherapy Evidence Database score was 5.4. Overall there was a significant positive effect favoring physical therapy for the critically ill to improve the quality of life (g = 0.40, 95% confidence interval 0.08, 0.71), physical function (g = 0.46, 95% confidence interval 0.13, 0.78), peripheral muscle strength (g = 0.27, 95% confidence interval 0.02, 0.52), and respiratory muscle strength (g = 0.51, 95% confidence interval 0.12, 0.89). Length of hospital (g = -0.34, 95% confidence interval -0.53, -0.15) and ICU stay (g = -0.34, 95% confidence interval -0.51, -0.18) significantly decreased and ventilator-free days increased (g = 0.38, 95% confidence interval 0.16, 0.59) following physical therapy in the ICU. There was no effect on mortality.

CONCLUSION

Physical therapy in the ICU appears to confer significant benefit in improving quality of life, physical function, peripheral and respiratory muscle strength, increasing ventilator-free days, and decreasing hospital and ICU stay. However, further controlled trials of better quality and larger sample sizes are required to verify the strength of these tentative associations.

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.

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.

Electrical muscle stimulation: an effective form of exercise and early mobilization to preserve muscle strength in critically ill patients

Purpose. This is a secondary analysis of previously published data to investigate the effects of electrical muscle stimulation (EMS) on strength of various muscle groups in critically ill patients. Methods. One hundred forty-two consecutive patients, with APACHE II score ≥ 13, were randomly assigned to the EMS or the control group. EMS sessions were applied daily on vastus lateralis, vastus medialis, and peroneus longus of both lower extremities. Various muscle groups were evaluated with the Medical Research Council (MRC) scale for muscle strength. Handgrip strength assessment was also employed. Results. Twenty four patients in the EMS group and 28 patients in the control group were finally evaluated. EMS patients achieved higher MRC scores than controls (P ≤ 0.05) in wrist flexion, hip flexion, knee extension, and ankle dorsiflexion. Collectively, the EMS group performed higher (P < 0.01) in the legs and overall. Handgrip strength correlated (P ≤ 0.01) with the upper and lower extremities' muscle strength and the overall MRC scores. Conclusions. EMS has beneficial effects on the strength of critically ill patients mainly affecting muscle groups stimulated, while it may also affect muscle groups not involved presenting itself as a potential effective means of muscle strength preservation and early mobilization in this patient population.

Electrical muscle stimulation prevents critical illness polyneuromyopathy: a randomized parallel intervention trial

INTRODUCTION

Critical illness polyneuromyopathy (CIPNM) is a common complication of critical illness presenting with muscle weakness and is associated with increased duration of mechanical ventilation and weaning period. No preventive tool and no specific treatment have been proposed so far for CIPNM. Electrical muscle stimulation (EMS) has been shown to be beneficial in patients with severe chronic heart failure and chronic obstructive pulmonary disease. Aim of our study was to assess the efficacy of EMS in preventing CIPNM in critically ill patients.

METHODS

One hundred and forty consecutive critically ill patients with an APACHE II score >or= 13 were randomly assigned after stratification to the EMS group (n = 68) (age:61 +/- 19 years) (APACHE II:18 +/- 4, SOFA:9 +/- 3) or to the control group (n = 72) (age:58 +/- 18 years) (APACHE II:18 +/- 5, SOFA:9 +/- 3). Patients of the EMS group received daily EMS sessions. CIPNM was diagnosed clinically with the medical research council (MRC) scale for muscle strength (maximum score 60, <48/60 cut off for diagnosis) by two unblinded independent investigators. Duration of weaning from mechanical ventilation and intensive care unit (ICU) stay were recorded.

RESULTS

Fifty two patients could be finally evaluated with MRC; 24 in the EMS group and 28 in the control group. CIPNM was diagnosed in 3 patients in the EMS group as compared to 11 patients in the control group (OR = 0.22; CI: 0.05 to 0.92, P = 0.04). The MRC score was significantly higher in patients of the EMS group as compared to the control group [58 (33 to 60) vs. 52 (2 to 60) respectively, median (range), P = 0.04). The weaning period was statistically significantly shorter in patients of the EMS group vs. the control group [1 (0 to 10) days vs. 3 (0 to 44) days, respectively, median (range), P = 0.003].

CONCLUSIONS

This study suggests that daily EMS sessions prevent the development of CIPNM in critically ill patients and also result in shorter duration of weaning. Further studies should evaluate which patients benefit more from EMS and explore the EMS characteristics most appropriate for preventing CIPNM.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT00882830.

Weakness in the ICU: a call to action

Muscle weakness is prevalent in critically ill patients and can have a dramatic effect on short- and long-term outcomes, yet there are currently no interventions with proven efficacy in preventing or treating this complication. In a new randomized trial, researchers found that serial electrical muscle stimulation significantly mitigated ultrasound-defined muscle atrophy, and the treatment was not linked to adverse effects. Although preliminary, these results, together with other recent studies, indicate a paradigm shift to a proactive approach in managing neuromuscular complications in the ICU.

Electrical muscle stimulation preserves the muscle mass of critically ill patients: a randomized study

Introduction

Critically ill patients are characterized by increased loss of muscle mass, partially attributed to sepsis and multiple organ failure, as well as immobilization. Recent studies have shown that electrical muscle stimulation (EMS) may be an alternative to active exercise in chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF) patients with myopathy. The aim of our study was to investigate the EMS effects on muscle mass preservation of critically ill patients with the use of ultrasonography (US).

Methods

Forty-nine critically ill patients (age: 59 ± 21 years) with an APACHE II admission score ≥13 were randomly assigned after stratification upon admission to receive daily EMS sessions of both lower extremities (EMS-group) or to the control group (control group). Muscle mass was evaluated with US, by measuring the cross sectional diameter (CSD) of the vastus intermedius and the rectus femoris of the quadriceps muscle.

Results

Twenty-six patients were finally evaluated. Right rectus femoris and right vastus intermedius CSD decreased in both groups (EMS group: from 1.42 ± 0.48 to 1.31 ± 0.45 cm, P = 0.001 control group: from 1.59 ± 0.53 to 1.37 ± 0.5 cm, P = 0.002; EMS group: from 0.91 ± 0.39 to 0.81 ± 0.38 cm, P = 0.001 control group: from 1.40 ± 0.64 to 1.11 ± 0.56 cm, P = 0.004, respectively). However, the CSD of the right rectus femoris decreased significantly less in the EMS group (-0.11 ± 0.06 cm, -8 ± 3.9%) as compared to the control group (-0.21 ± 0.10 cm, -13.9 ± 6.4%; P < 0.05) and the CSD of the right vastus intermedius decreased significantly less in the EMS group (-0.10 ± 0.05 cm, -12.5 ± 7.4%) as compared to the control group (-0.29 ± 0.28 cm, -21.5 ± 15.3%; P < 0.05).

Conclusions

EMS is well tolerated and seems to preserve the muscle mass of critically ill patients. The potential use of EMS as a preventive and rehabilitation tool in ICU patients with polyneuromyopathy needs to be further investigated.

Trial Registration

clinicaltrials.gov: NCT00882830

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

BACKGROUND

Critical illness polyneuro-and/or myopathy (CIP/CIM) is an important and frequent complication in the intensive care unit (ICU), causing delayed weaning from mechanical ventilation. It may increase ICU stay and mortality.

OBJECTIVES

To examine the ability of any intervention to prevent the occurrence of CIP/CIM.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Trials Register (October 2007), MEDLINE (January 1950 to April 2008), EMBASE (January 1980 to October 2007), checked bibliographies and contacted trial authors and experts in the field.

SELECTION CRITERIA

All randomised controlled trials (RCTs), examining the effect of any intervention on the incidence of CIP/CIM in adult medical or surgical ICU patients. The primary outcome measure was the incidence of CIP/CIM after at least seven days in ICU, based on electrophysiological or clinical examination.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data.

MAIN RESULTS

Three out of nine identified trials, provided data on our primary outcome measure. Two trials examined the effects of intensive insulin therapy versus conventional insulin therapy. Eight hundred and twenty-five out of 2748 patients randomised, were included in the analysis. The incidence of CIP/CIM was significantly reduced with intensive insulin therapy in the population screened for CIP/CIM (relative risk (RR) 0.65, 95% confidence interval (CI) 0.55 to 0.78) and in the total population randomised (RR 0.60, 95% CI 0.49 to 0.74). Duration of mechanical ventilation, duration of ICU stay and 180-day mortality but not 30-day mortality, were significantly reduced with intensive insulin therapy, in both the total and the screened population. Intensive insulin therapy significantly increased hypoglycaemic events and recurrent hypoglycaemia. Death within 24 hours of the hypoglycaemic event was not different between groups. The third trial examined the effects of corticosteroids versus placebo in 180 patients with prolonged acute respiratory distress syndrome. No significant effect of corticosteroids on CIP/CIM was found (RR 1.09, 95% CI 0.53 to 2.26). No effect on 180-day mortality, new serious infections and glycaemia at day seven was found. A trend towards fewer episodes of pneumonia and reduction of new events of shock was shown.

AUTHORS' CONCLUSIONS

Substantial evidence shows that intensive insulin therapy reduces the incidence of CIP/CIM, the duration of mechanical ventilation, duration of ICU stay and 180-day mortality. There was a significant associated increase in hypoglycaemia. Further research needs to identify the clinical impact of this and strategies need to be developed to reduce the risk of hypoglycaemia. Limited evidence shows no significant effect of corticosteroids on the incidence of CIP/CIM, or on any of the other secondary outcome measures, except for a significant reduction of new episodes of shock. Strict diagnostic criteria for the purpose of research should be defined. Other interventions should be investigated in randomised controlled trials.

Electrostimulation for the prevention of deep venous thrombosis in patients with major trauma: a prospective randomized study

BACKGROUND

Current methods of posttraumatic thromboprophylaxis (heparins and sequential compression devices) are inadequate. New methods should be tested. Muscle electrostimulation (MEST) has been used over the years with mixed-but predominantly encouraging-results for a variety of conditions, including prevention of deep venous thrombosis (DVT). It has not been tested in multiple trauma patients.

METHODS

Trauma patients with Injury Severity Score higher than 9 who were admitted to the intensive care unit and had a contraindication for prophylactic heparinization were randomized to groups MEST and control. MEST patients received 30-minute MEST sessions twice daily for 7 to 14 days. Venous flow velocity and venous diameter were measured by duplex venous scan. Venography-or, if not available, duplex-was used to evaluate the presence of proximal and peripheral DVT between days 7 and 15.

RESULTS

After exclusions, 26 MEST and 21 control patients completed the study and received outcome evaluation by venography (25) or duplex (22). Three patients in each group developed proximal DVT (11.5% vs 14%, P = .79), and an additional 4 (15%) MEST group and 3 (14%) control group patients developed peripheral DVT ( P = .96). There was no difference in venous flow velocity or venous diameter between the groups.

CONCLUSIONS

MEST was not effective in decreasing DVT rates in major trauma patients.

Randomised controlled trial of transcutaneous electrical muscle stimulation of the lower extremities in patients with chronic obstructive pulmonary disease

BACKGROUND

Although exercise training improves exercise tolerance in most patients with chronic obstructive pulmonary disease (COPD), some patients with severe disease may not be able to tolerate exercise training due to incapacitating breathlessness. Transcutaneous electrical muscle stimulation (TCEMS) has been shown to improve muscle strength, muscle mass, and performance in paraplegics, patients with knee ligament injury, and patients with peripheral vascular disease. We hypothesised that TCEMS of the lower extremities can improve muscle strength and exercise tolerance in patients with moderate to severe COPD.

METHODS

A randomised controlled trial of TCEMS of the lower extremities was performed in 18 medically stable patients of mean (SD) age 60.0 (1.5) years with a mean forced expiratory volume in 1 second (FEV(1)) of 1.03 (0.10) l (38% predicted) and residual volume/total lung capacity (RV/TLC) of 59 (2)%. Stimulation of the lower extremities was performed three times a week, 20 minutes each session, for six continuous weeks. Quadriceps and hamstring muscle strength, exercise capacity, and peak oxygen uptake were measured at baseline and after 6 weeks of stimulation.

RESULTS

TCEMS improved both the quadriceps strength (by 39.0 (20.4)% v 9.0 (8.1)%, p=0.046) and hamstring muscle strength (by 33.9 (13.0)% v 2.9 (4.7)%, p=0.038) in the treated (n=9) and sham treated (n=9) groups, respectively. The improvement in muscle strength carried over to better performance in the shuttle walk test in the treated group (36.1% v 1.6% in the treated and sham groups respectively, p=0.007, Mann-Whitney U test). There was no significant change in lung function, peak workload, or peak oxygen consumption in either group. Muscle stimulation was well tolerated by the patients with no dropouts and better than 95% compliance with the protocol.

CONCLUSIONS

TCEMS of peripheral muscles can be a useful adjunct to the comprehensive pulmonary rehabilitation of patients with COPD.

Muscle strength as a predictor of loss of functional status in hospitalized patients

OBJECTIVE

The incidence of protein-calorie malnutrition in hospitalized adult patients can reach 30% to 50% and adversely affect clinical outcome. We evaluated the efficacy of muscle strength to predict functional derangement and detect early changes in nutrition status in hospitalized patients.

METHODS

Patients hospitalized at medical and surgical wards from two different hospitals in Santiago, Chile, were studied during their hospital stay. Subjective Global Assessment of nutrition status and laboratory parameters were measured on admission. Anthropometric measures, handgrip dynamometry, and maximal inspiratory and expiratory pressures were measured on admission and discharge. The Karnofsky index was used to assess functional status. Twice weekly, caloric balance was calculated with indirect calorimetry and assessment of dietary intake.

RESULTS

From the initial selection of patients (n = 70), 50 patients (26 men and 24 women) completed the study. Median hospital stay was 10 d. Subjective Global Assessment was associated with anthropometric data, handgrip dynamometry, and serum levels of total proteins. Patients in whom functional status declined during hospital stay, on admission had lower left handgrip strength, a worse Subjective Global Assessment classification, were older, and had lower fat mass. No association between caloric balance during hospital stay and changes in muscle strength was observed.

CONCLUSIONS

Subjective Global Assessment, handgrip strength, and fat mass were good predictors for the decline in functional status during hospital stay. No association between caloric balance and changes in muscle strength was observed.

Improvement of thigh muscles by neuromuscular electrical stimulation in patients with refractory heart failure: a single-blind, randomized, controlled trial

OBJECTIVE

To determine the impact of an 8-wk neuromuscular stimulation program of thigh muscles on strength and cross-sectional area in patients with refractory heart failure listed for transplantation.

DESIGN

Forty-two patients with a stable disease course were assigned randomly to a stimulation group (SG) or a control group (CG). The stimulation protocol consisted of biphasic symmetric impulses with a frequency of 50 Hz and an on/off regime of 2/6 sec.

RESULTS

Primary outcome measures were isometric and isokinetic thigh muscle strength and muscle cross-sectional area. Our results showed an increase of muscle strength by mean 22.7 for knee extensor and by 35.4 for knee flexor muscles. The CG remained unchanged or decreased by -8.4 in extensor strength. Cross-sectional area increased in the SG by 15.5 and in the CG by 1.7.

CONCLUSIONS

Activities of daily living as well as quality of life increased in the SG but not in the CG. Subscales of the SF-36 increased significantly in the SG, especially concerning physical functioning by +7.5 (1.3-30.0), emotional role by +33.3 (0-66.6), and social functioning by +18.8 (0-46.9), all P < 0.05. Neither a change nor a decrease was observed in the CG. Neuromuscular electrical stimulation of thigh muscles in patients with refractory heart failure is effective in increasing muscle strength and bulk and positively affects the perception of quality of life and activities of daily living.

Neuromuscular Blockade Does Not Decrease Oxygen Consumption or Energy Expenditure Beyond Sedation in the Mechanically Ventilated Child

Minimizing the high oxygen consumption and energy expenditure of the critically ill is an important therapeutic goal. This study was done to determine if neuromuscular blockade decreases oxygen consumption or energy expenditure more than sedation alone in the mechanically ventilated child. Twelve burned children, with an average age of 5.1- 1.6 yrs, average weight of 22.8 − 6.5 kg, and average burn size of 28.3 − 5.8% of the body surface, scheduled for a planned surgical procedure under general anesthesia were enrolled in this prospective self-controlled study. In conjunction with planned operative procedures and using an intravenous anesthetic technique, the children underwent expired gas collection before and after neuromuscular blockade was induced. Expired gas was collected and analyzed for the fractional concentration of oxygen and carbon dioxide. Oxygen consumption (VO2), carbon dioxide production (VCO2), energy expenditure (EE), and respiratory quotient (RQ) were calculated. We found no significant difference in EE, VO2, VCO2, or RQ between the well-sedated and mechanically ventilated and the well-sedated, mechanically ventilated and paralyzed states. We therefore concluded that neuromuscular blockade does not decrease energy expenditure in the otherwise well-sedated burned child.

Nutritional and metabolic response to acute spinal-cord injury

The metabolic response to complete spinal cord injury was prospectively studied in 10 patients with Frankel class A spinal cord injury. Weekly excretory and balance studies profile the changes in nitrogen, calcium, and 3-methylhistidine excretion in relation to body weight and metabolic rate. The initial resting energy expenditures were 10% below what was predicted, and body weight decreased by 10%. Nitrogen excretion paralleled the changes in body weight. Calcium excretion increased for 3 weeks and reached a plateau 150% above baseline. Our results chronicle the magnitude of metabolic response to spinal shock. Comparison with reported values shows this response exceeds that seen in immobilized patients. Nitrogen excretion rose to levels seen in highly stressed patients and must be considered in the management of patients with acute spinal-cord injury.

Adjunctive therapy for nutritional support in hospitalized patients

It would be unrealistic to expect that a single adjuvant modality may be applicable to all patients receiving nutritional support, either IV or enterally. Further characterization of the optimal application of each adjuvant modality may establish the precise role of adjuvant anabolic stimulation throughout the clinical course. Better definition of IV formulas with addition of stable glutamine dipeptides may be of benefit in patients at high risk for sepsis and significant skeletal muscle wasting, while use of met-hGH may improve nitrogen retention and whole-body net protein accrual under these circumstances. Chronic, low- to moderate-intensity exercise may be applicable in a select group of patients, particularly patients at risk for developing complications after surgical intervention in whom aggressive nutritional support has been shown to improve operative outcome.