Eleftherios Karatzanos

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

IntroductionCritically 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).MethodsForty-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.ResultsTwenty-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).ConclusionsEMS 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 Registrationclinicaltrials.gov: NCT00882830

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

IntroductionCritical 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.MethodsOne hundred and forty consecutive critically ill patients with an APACHE II score ≥ 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.ResultsFifty 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].ConclusionsThis 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 NumberClinicalTrials.gov NCT00882830

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

BackgroundNeuromuscular 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.MethodsWe 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.ResultsThe 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.ConclusionsNMES 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.

Short-term Systemic Effect of Electrical Muscle Stimulation in Critically Ill Patients

BACKGROUND Our study assessed the short-term effect of electrical muscle stimulation (EMS) of the lower extremities on the thenar muscle microcirculation of patients who are critically ill. METHODS Twenty-nine hospital ICU patients (19 men; mean [+/- SD] age, 58 +/- 19 years; mean acute physiology and chronic health evaluation score, 17 +/- 5; mean sequential organ failure assessment score, 9 +/- 3) underwent a 45-min session of EMS of the lower extremities. BP and heart rate were measured, and blood samples were retrieved. Tissue oxygen saturation (Sto(2)) was assessed with near infrared spectroscopy at the thenar muscle with a vascular occlusion before and after EMS. A control group of six patients who were critically ill (4 men; mean age, 50 +/- 19 years) also were included in the study. RESULTS The mean Sto(2) did not differ significantly before and after the EMS session (81 +/- 16% vs 83 +/- 16%, respectively). The oxygen consumption rate during vascular occlusion differed significantly before the beginning and at the end of the session (20 +/- 9%/min vs 22 +/- 9%/min, respectively; p < 0.05). The reperfusion rate differed significantly before the beginning and at the end of the session (299 +/- 177%/min vs 375 +/- 182%/min, respectively; p < 0.05). Heart rate increased significantly at the end of the session (94 +/- 16 beats/min vs 99 +/- 16 beats/min, respectively; p < 0.05) as did systolic BP (127 +/- 21 mm Hg vs 133 +/- 23 mm Hg; p < 0.05, respectively). The Sto(2) value did not differ between the two measurements in control patients. CONCLUSION The data suggest that EMS has a systemic effect on microcirculation. These results suggest that further studies are needed to explore the potential use of EMS as a preventive and rehabilitation tool in critically ill patients.

The addition of strength training to aerobic interval training: effects on muscle strength and body composition in CHF patients.

PURPOSE: The loss of lean muscle mass and muscle strength is a common problem in chronic heart failure (CHF) patients. Endurance training is efficient in improving patient exercise capacity. This study sought to evaluate the additional effects of strength training on muscle strength and body composition in chf patients participating in an interval training program. METHODS: Twenty consecutive, stable CHF patients participated in a rehabilitation program. Subjects were randomly assigned to aerobic (n = 10) or combined aerobic plus strength training group (n = 10). Aerobic group performed interval training on cycle ergometers. Strength training incorporated exercises for various muscle groups, including quadriceps, hamstrings, biceps brachii, and the deltoids. Both regimes were of the same duration. Body composition was evaluated by whole-body dual energy x-ray absorptiometry and quadriceps strength by the sum of the 2-repitition maximum (2-RM) test for each leg. Peak oxygen uptake ( ) and peak work load (Wpeak) as well as oxygen uptake ( ) and workload at anaerobic threshold (WAT) were evaluated by a symptom limited cardiopulmonary exercise testing. RESULTS: Concerning leg lean mass, no significant within-subjects or between-groups changes were observed (P > .05). Both groups improved in 2-RM test (P < .05), while a significant difference was observed between groups (P < .05). and and Wpeak and WAT were equally improved between training groups (P < .05). CONCLUSIONS: Combined aerobic interval and strength training induces a greater benefit than interval training alone on muscle strength in CHF patients. Adaptations other than hypertrophy, such as muscle fiber type alterations and/or neuromuscular adjustments, may account for these results.

Physical exercise improves the peripheral microcirculation of patients with chronic heart failure.

PURPOSE Patients with chronic heart failure (CHF) present with microcirculation alterations, partially attributed to endothelial dysfunction. Exercise training has been shown to induce beneficial effects in CHF patients. The aim of our study was to assess the effect of physical exercise on the microcirculation of CHF patients by near-infrared spectroscopy (NIRS). METHODS Sixteen consecutive stable CHF patients (men, n = 10; mean age = 50 ± 12 years) participated in a 3-month rehabilitation program (3 sessions per week). All patients performed symptom-limited, ramp-incremental cardiopulmonary exercise testing on a cycle ergometer before and after the completion of the program. Measurements included peak oxygen uptake (VO2peak), VO2 at anaerobic threshold (AT), and first-degree slope of VO2 during the first minute of recovery (VO2/t slope). Tissue oxygen saturation was continuously measured by NIRS at the thenar muscle during a 3-minute vascular occlusion with a pneumatic cuff (occlusion technique) before and after the rehabilitation program. RESULTS The oxygen reperfusion rate (%/min) following the release of vascular occlusion increased significantly after the rehabilitation program (450 ± 105 to 532 ± 151, P = .004) as did vascular reactivity (from 27 ± 13%/min to 39 ± 21%/min, P = .006). In addition, there was a significant increase in VO2peak and AT (from 14.3 ± 4.7 mL · kg−1 · min−1 to 16.7 ± 6.3 mL · kg−1 · min−1 and from 9.5 ± 3.6 mL · kg−1 · min−1 to 11.3 ± 4 mL · kg−1 · min−1, P = .007 and P = .012, respectively) as well as in VO2/t slope (from 0.35 ± 0.17 to 0.51 ± 0.07 mL · kg−1 · min−1, P = .005). CONCLUSIONS Peripheral microcirculation of CHF patients measured by NIRS improved after the rehabilitation program. NIRS is a noninvasive technique that could be used to evaluate the effect of rehabilitation on the peripheral microcirculation of CHF patients.

Effects of interval exercise training on respiratory drive in patients with chronic heart failure

BACKGROUND Patients with chronic heart failure (CHF) suffer from ventilatory abnormalities. This study examined the effects of interval exercise training on the respiratory drive in CHF patients. METHODS Forty-six clinically stable CHF patients (38 males/8 women, mean age = 53 +/- 11 years) participated in an exercise rehabilitation program (ERP) 3 times/week, for 12 weeks by interval training modality with or without the addition of resistance training. All patients underwent symptom-limited cardiopulmonary exercise testing (CPET), and measurements of mouth occlusion pressure at 100 ms (P(0.1)) and maximum inspiratory muscle strength (P(Imax)) before and after ERP. Respiratory drive was estimated by mouth occlusion pressure P(0.1) and P(0.1)/P(Imax) ratio at rest, and the ventilatory pattern by resting mean inspiratory flow (V(T)/T(I)) and by V(T)/T(I) at identical CPET workloads, before and after ERP. We also studied a control non exercising group of 11 patients (8 men and 3 women). RESULTS P(0.1) at rest decreased from 3.04 +/- 1.52 to 2.62 +/- 0.9 cmH(2)O (p = 0.015), P(0.1)/P(Imax) % at rest from 4.56 +/- 3.73 to 3.69 +/- 2.03 (p = 0.006), resting V(T)/T(I) from 0.44 +/- 0.10 to 0.41 +/- 0.10 l/s (p = 0.014), and V(T)/T(I) at identical work rate from 2.13 +/- 0.59 to 1.93 +/- 0.58 l/s (p = 0.001) after ERP. VO(2) at peak exercise increased from 16.3 +/- 4.8 to 18.5 +/- 5.3 ml/kg/min (p < 0.001) in the exercise group. No improvement was noted in the control group. CONCLUSIONS ERP by interval training improves the respiratory drive and ventilatory pattern at rest and during exercise in CHF patients.

Hormonal imbalance in relation to exercise intolerance and ventilatory inefficiency in chronic heart failure

BACKGROUND Skeletal muscle wasting is associated with altered catabolic/anabolic balance and poor prognosis in patients with chronic heart failure (CHF). This study evaluated catabolic and anabolic abnormalities in relation to disease severity in CHF patients. METHODS Forty-two stable CHF patients (34 men; aged 56±12 years, body mass index, 27±5 kg/m2) receiving optimal medical treatment underwent incremental symptom-limited cardiopulmonary exercise testing on a cycle ergometer. Blood samples were drawn within 10 days to determine serum cortisol, plasma adrenocorticotropin (ACTH), and serum dehydroepiandrosterone sulfate, insulin-like growth factor 1, growth hormone, and total testosterone in men. RESULTS Patients with higher cortisol levels presented with impaired peak oxygen uptake (Vo2 peak: 18.3±3.9 vs. 14.2±3.7 ml/kg/min, p<0.01), ventilatory (Ve) response to exercise (Ve/carbon dioxide output [Vco2] slope: 36±6 vs 30±5, p<0.01), and chronotropic reserve ([peak heart rate [HR]--resting HR/220--age--resting HR]×100%: 40±19 vs. 58±18, p=0.01) compared with those with lower serum cortisol. Cortisol was inversely correlated with Vo2 peak, (r = -0.57; p<0.01) and was correlated with Ve/Vco2 slope (r = 0.47; p<0.01) and chronotropic reserve (r = 0.44; p = 0.017). In multivariate regression analysis, cortisol was an independent predictor of Vo2peak (R2 = 0.365, F = 12.5, SE = 3.4; p≤0.001) and Ve/Vco2 slope (R2 = 0.154; F = 8.5; SE = 5.96; p = 0.006), after accounting for age, body mass index, sex, CHF etiology, creatinine, left ventricular ejection fraction, and ACTH in all patients. In men, cortisol and dehydroepiandrosterone levels were both independent predictors of Vo2peak (R2 = 0.595, F = 24.53, SE = 2.76; p<0.001) after accounting also for all measured hormones, whereas cortisol remained the only independent predictor of Ve/Vco2 slope (R2 = 0.133; F = 6.1; SE = 6.2; p = 0.02). CONCLUSIONS Enhanced catabolic status is significantly associated with exercise intolerance, ventilatory inefficiency, and chronotropic incompetence in CHF patients, suggesting a significant contributing mechanism to their limited functional status.

Exercise training improves characteristics of exercise oscillatory ventilation in chronic heart failure

Background Exercise oscillatory ventilation in chronic heart failure has been suggested as a factor related to adverse cardiac events, aggravated prognosis and higher mortality. Exercise training is well known to affect exercise capacity and mechanisms of pathophysiology beneficially in chronic heart failure. Little is known, however, about the exercise training effects on characteristics of exercise oscillatory ventilation in chronic heart failure patients. Design and methods Twenty (out of 38) stable chronic heart failure patients exhibited exercise oscillatory ventilation (age 54 ± 11 years, peak oxygen uptake 15.0 ± 5.0 ml/kg per minute). Patients attended 36 sessions of high intensity interval exercise. All patients underwent cardiopulmonary exercise testing before and after the programme. Assessment of exercise oscillatory ventilation was based on the amplitude of cyclic fluctuations in breathing during rest and exercise. All values are mean ± SD. Results Exercise training reduced (P < 0.05) the percentage of exercise oscillatory ventilation duration (79.0 ± 13.0 to 50.0 ± 25.0%), while average amplitude (5.2 ± 2.0 to 4.9 ± 1.6 L/minute) and length (44.0 ± 10.9 to 41.0 ± 6.7 seconds) did not change (P > 0.05). Exercise oscillatory ventilation patients also increased exercise capacity (P < 0.05). Conclusions A rehabilitation programme based on high intensity interval training improved exercise oscillatory ventilation observed in chronic heart failure patients, as well as cardiopulmonary efficiency and functional capacity.

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 ± 16 years) 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). &Dgr;MRC% 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 HighlightsRandomized trial implementing Neuromuscular Electrical Stimulation (NMES) and rehabilitation program in ICU survivors.The program was performed from ICU discharge to hospital discharge.Outcome measures included assessment of muscle strength, functional ability and hospital length of stay.MRC, handgrip strength, functional status and length of stay did not differ at hospital.MRC improved significantly in patients with ICU‐acquired weakness after 2 weeks of NMES.Intervention may be beneficial in ICU survivors with ICU‐acquired weakness.