Inspiratory Muscle Training in Phase 1 and 2 Postoperative Cardiac Rehabilitation Following Coronary Artery Bypass Graft Surgery: Systematic Review with Meta-Analysis

OBJECTIVE

This study aimed to determine the effects of inspiratory muscle training (IMT) on exercise capacity, respiratory muscle strength, length of hospital stay (LOS), and quality of life (QOL) following coronary artery bypass graft surgery.

METHODS

The search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane Handbook and included the databases MEDLINE, EMBASE, CINAHL, Scopus, and CENTRAL. The review included randomized controlled trials utilizing IMT during phase 1 or 2 postoperative cardiac rehabilitation (PoCR) versus alternative treatment (active or passive control) in patients following coronary artery bypass graft surgery.

RESULTS

Fifteen studies were included (11 phase 1 studies, 4 phase 2 studies) with no reported adverse events. In phase 1 PoCR, IMT reduced the LOS (-1.02 days; 95% CI = -2.00 to -0.03) and increased exercise capacity (6-minute walk distance [6MWD]).(+75.46 m; 95% CI = 52.34 to 98.57), and maximal inspiratory pressure (MIP) (10.46 cm H2O; 95% CI = 2.83 to 18.10), but had no effect on maximal expiratory pressure. In phase 2 PoCR, IMT increased 6MWD (45.84 m; 95% CI = 10.89 to 80.80), MIP (-23.19 cm H2O; 95% CI = -31.31 to -15), maximal expiratory pressure (20.18 cm H2O; 95% CI = 9.60 to 30.76), and QOL (-11.17; 95% CI = -17.98 to -4.36), with no effect on peak oxygen uptake. There was a high risk of bias for MIP (75% of the phase 1 studies) and 6MWT (1 of 4 phase 2 studies). The quality of the evidence ranged from very low to moderate.

CONCLUSIONS

IMT significantly improves exercise capacity, respiratory muscle strength, LOS, and QOL in phase 1 and 2 PoCR.

IMPACT

IMT may benefit patients during phase 1 and 2 of PoCR, considering the safety, low cost, and potential benefits.

A Southern addiction evaluation project: investigating the impact of addiction through a survey HBSC based

Background

Adolescence is a critical phase of development characterized by numerous physical, psychological and social changes. During this stage, individuals may engage in experimentation and risky behavior, leading to increased vulnerability to addiction. This article aims to present the results of a survey based on the HBSC (Health Behavior in School-aged Children) surveillance model in a province of Southern Italy for primary and secondary school students.

Methods

We conducted a prospective study from March 2020 to April 2023 through the administration of a questionnaire to students of the healthcare faculties of the University of Messina and primary and secondary school students, composed of 19 items and based on HBSC surveillance.

Results

We collected a total of 664 questionnaires. We found that smoking habits increase with age: approximately 31% of secondary school students declare they are real smokers compared to 40% of HCP students. At least once, in the three study groups, students experienced alcohol consumption at different rates, with younger students having a greater propensity to drink than older students. Fortunately, in our sample, no middle school students had tried cannabis. At the same time there is a surprising decrease in gambling in all categories compared to national data.

Conclusions

The presence of addictive behaviors in our sample was found to be widespread despite being in line with the national trend. Furthermore, we have observed a reduction in recent years which needs to be investigated to assess the reasons. Primary prevention is probably the main weapon in the hands of politicians and must be applied early in school and community settings to reduce prevalence.

Longitudinal strain and myocardial work in symptomatic patients having recovered from COVID-19 and possible associations with the severity of the disease

COVID-19 may have residual consequences in multiple organs, including the cardiovascular system. The purpose of the present investigation is to quantify myocardial function in symptomatic individuals with long COVID and investigate the association between illness severity and myocardial function. A retrospective cross-sectional study was conducted in which symptomatic individuals with previous COVID-19 underwent echocardiographic analysis of left ventricle global longitudinal strain (LVGLS) and myocardial work (MW). Individuals also performed cardiopulmonary testing (CPX) to assess peak oxygen uptake (VO2peak). Differences between illness severity subgroups were analyzed by the Mann-Whitney test. Correlations were calculated using the Spearman correlation test. Multilinear regressions were performed to evaluate the influences of COVID-19 severity, body mass index, age, and sex on MW. Fifty-six individuals were included (critical subgroup: 17; moderate/severe subgroup: 39), 59% females; median age: 56 years (IQR: 43-63). CPX revealed a substantial reduction in VO2peak (median of 53% of predicted values). LVGLS were not statistically different between subgroups. Global wasted work (GWW) was higher in the critical subgroup [146 (104-212) versus 121 (74-163) mmHg%, p = 0.01], and global work efficiency (GWE) was lower in this subgroup [93 (91-95) versus 94 (93-96), p = 0.03]. Illness severity was the only independent predictor of GWW and GWE (GWW: r2 = 0.167; p = 0.009; GWE: r2 = 0.172; p = 0.005) in multilinear regressions. In our study with long COVID-19 individuals, despite having a similar LVGLS, patients had subclinical LV dysfunction, demonstrated only by an increase in GWW and a decrease in GWE.

Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test

BACKGROUND

Central Illustration : Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test CPET: cardiopulmonary exercise test; TUG: timed up and go test; VO2peak: peak oxygen consumption.

BACKGROUND

The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature.

OBJECTIVES

Test the association between TUG and peak oxygen consumption (VO2peak), construct an equation based on TUG to predict VO2peak, and determine a cutoff point to estimate VO2peak ≥ 20 mL/kg/min.

METHODS

This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05.

RESULTS

The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO2peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO2peak and TUG was r = -0.54 (p < 0.001), and R2 was 0.30. The following equation was developed based on TUG: V O 2 peak = 33.553 + ( - 0.149 × age ) + ( - 0.738 × TUG ) + ( - 2.870 × sex ) ; a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R2: 0.40). The VO2peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO2peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86).

CONCLUSIONS

TUG and VO2peak showed a significant association. A prediction equation for VO2peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.

Early Neuromuscular Electrical Stimulation Preserves Muscle Size and Quality and Maintains Systemic Levels of Signaling Mediators of Muscle Growth and Inflammation in Patients with Traumatic Brain Injury: A Randomized Clinical Trial

Objective

To investigate the effects of an early neuromuscular electrical stimulation (NMES) protocol on muscle quality and size as well as signaling mediators of muscle growth and systemic inflammation in patients with traumatic brain injury (TBI).

Design

Two-arm, single-blinded, parallel-group, randomized, controlled trial with a blinded assessment. Setting. Trauma intensive care unit at a university hospital. Participants. Forty consecutive patients on mechanical ventilation (MV) secondary to TBI were prospectively recruited within the first 24 hours following admission. Interventions. The intervention group (NMES; n = 20) received a daily session of NMES on the rectus femoris muscle for five consecutive days (55 min/each session). The control group (n = 20) received usual care. Main Outcome Measures. Muscle echogenicity and thickness were evaluated by ultrasonography. A daily blood sample was collected to assess circulating levels of insulin-like growth factor I (IGF-I), inflammatory cytokines, and matrix metalloproteinases (MMP).

Results

Both groups were similar at baseline. A smaller change in muscle echogenicity and thickness (difference between Day 1 and Day 7) was found in the control group compared to the NMES group (29.9 ± 2.1 vs. 3.0 ± 1.2, p < 0.001; -0.79 ± 0.12 vs. -0.01 ± 0.06, p < 0.001, respectively). Circulating levels of IGF-I, pro-inflammatory cytokines (IFN-y), and MMP were similar between groups.

Conclusion

An early NMES protocol can preserve muscle size and quality and maintain systemic levels of signaling mediators of muscle growth and inflammation in patients with TBI. This trial is registered with https://www.ensaiosclinicos.gov.br under number RBR-2db.

Inspiratory muscle training on quality of life in individuals with spinal cord injury: A systematic review and meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

The objective was to summarize the effectiveness of Inspiratory Muscle Training (IMT) on the quality of life in individuals with Spinal Cord Injury (SCI).

METHODS

An online systematic literature search was conducted in the following databases: PubMed/MEDLINE, PubMed CENTRAL, EMBASE, ISI Web of Science, SciELO, CINAHL/SPORTDiscus, and PsycINFO. Randomized and non-randomized clinical studies investigating the effectiveness of IMT in quality of life were included in the present study. The results used the mean difference and 95% confidence interval for maximal inspiratory pressure (MIP), forced expiratory volume in 1 s (FEV1), maximal expiratory pressure (MEP), and the standardized mean differences for the quality of life and maximum ventilation volume.

RESULTS

The search found 232 papers, and after the screening, four studies met the inclusion criteria and were included in the meta-analytical procedures (n = 150 participants). No changes were demonstrated in the quality of life domains (general health, physical function, mental health, vitality, social function, emotional problem, and pain) after IMT. The IMT provided a considerable effect over the MIP but not on FEV1 and MEP. Conversely, it was not able to provide changes in any of the quality of life domains. None of the included studies evaluated the IMT effects on the expiratory muscle maximal expiratory pressure.

CONCLUSION

Evidence from studies shows that inspiratory muscle training improves the MIP; however, this effect does not seem to translate to any change in the quality of life or respiratory function outcomes in individuals with SCI.

Cardiopulmonary Exercise Testing in Post-COVID-19 Patients: Where Does Exercise Intolerance Come From?

BACKGROUND

Post-COVID-19 exercise intolerance is poorly understood. Cardiopulmonary exercise testing (CPET) can identify the underlying exercise limitations.

OBJECTIVES

To evaluate the source and magnitude of exercise intolerance in post-COVID-19 subjects.

METHODS

Cohort study assessing subjects with different COVID-19 illness severities and a control group selected by propensity score matching. In a selected sample with CPET prior to viral infection, before and after comparisons were performed. Level of significance was 5% in the entire analysis.

RESULTS

One hundred forty-four subjects with COVID-19 were assessed (median age: 43.0 years, 57% male), with different illness severities (60% mild, 21% moderate, 19% severe). CPET was performed 11.5 (7.0, 21.2) weeks after disease onset, with exercise limitations being attributed to the peripheral muscle (92%), and the pulmonary (6%), and cardiovascular (2%) systems. Lower median percent-predicted peak oxygen uptake was observed in the severe subgroup (72.2%) as compared to the controls (91.6%). Oxygen uptake differed among illness severities and controls at peak and ventilatory thresholds. Conversely, ventilatory equivalents, oxygen uptake efficiency slope, and peak oxygen pulse were similar. Subgroup analysis of 42 subjects with prior CPET revealed significant reduction in only peak treadmill speed in the mild subgroup and in oxygen uptake at peak and ventilatory thresholds in the moderate/severe subgroup. By contrast, ventilatory equivalents, oxygen uptake efficiency slope, and peak oxygen pulse did not change significantly.

CONCLUSIONS

Peripheral muscle fatigue was the most common exercise limitation etiology in post-COVID-19 patients regardless of the illness severity. Data suggest that treatment should emphasize comprehensive rehabilitation programs, including aerobic and muscle strengthening components.

Analysis of physical function, muscle strength, and pulmonary function in surgical cancer patients: a prospective cohort study

The aim of this study was to investigate mobility, physical functioning, peripheral muscle strength, inspiratory muscle strength and pulmonary function in surgical cancer patients admitted to an intensive care unit (ICU). We conducted a prospective cohort study with 85 patients. Mobility, physical functioning, peripheral muscle strength, inspiratory muscle strength, and pulmonary function were assessed using the following tests: ICU Mobility Scale (IMS); Chelsea Critical Care Physical Assessment (CPAx); handgrip strength and Medical Research Council Sum-Score (MRC-SS); maximal inspiratory pressure (MIP) and S-Index; and peak inspiratory flow, respectively. The assessments were undertaken at ICU admission and discharge. The data were analyzed using the Shapiro-Wilk and Wilcoxon tests and Spearman's correlation coefficient. Significant differences in inspiratory muscle strength, CPAx, grip strength, MRC-SS, MIP, S-Index, and peak inspiratory flow scores were observed between ICU admission and discharge. Grip strength showed a moderate correlation with MIP at admission and discharge. The findings also show a moderate correlation between S-Index scores and both MIP and peak inspiratory flow scores at admission and a strong correlation at discharge. Patients showed a gradual improvement in mobility, physical functioning, peripheral and inspiratory muscle strength, and inspiratory flow during their stay in the ICU.

Impact of COVID-19's on Cardiovascular Rehabilitation Programs in Brazil: An Online Survey-Based Cross-Sectional Study

BACKGROUND

The COVID-19 pandemic had an impact on cardiovascular rehabilitation (CR) programs in Brazil.

OBJECTIVES

To describe the characteristics of CR programs in Brazil, the impacts of the first epidemiological wave of COVID-19 (first 60 days) on the programs and present the initiatives used to overcome the impacts.

METHOD

This cross-sectional and retrospective study utilized a specific online survey. Participants were coordinators of CR programs. Variables were presented by Brazilian geographic region and as the following categories: demographic, clinical and operational characteristics. The significance level for statistical analysis was set at 5%.

RESULTS

Fifty-nine CR programs were responsible for 5,349 patients, of which only 1,817 were post-acute cardiovascular events, which corresponded to 1.99% of hospitalized patients in the month prior to the survey (n=91,231). The greatest impact was the suspension of on-site activities, which occurred similarly in areas with the highest and the lowest rates of COVID-19 in the period. Forty-five programs (75%) were shortly interrupted, while three (5%) were ended. All 42 programs that already used remote rehabilitation strategies noticed a substantial increase in activities, based primarily on the use of media and video calling. Only three (5%) considered safe to see patients during the first 60 days.

CONCLUSIONS

There was a reduction in the number of CR programs with the COVID-19 pandemic. Telerehabilitation activities increased during the first two months of the COVID-19 pandemic, but this was not enough to overcome the reduction in CR program activities across Brazil.

A call to action for blood flow restriction training in older adults with or susceptible to sarcopenia: A systematic review and meta-analysis

Background: The extent to which exercise training with blood flow restriction (BFR) improves functional performance (FP) in people with sarcopenia remains unclear. We performed a comprehensive search of BFR training in subjects with sarcopenia or susceptible to sarcopenia hoping to perform a systematic review and meta-analysis on the effects of BFR on FP in older adults without medical disorders, but with or susceptible to sarcopenia.

Methods: PubMed and the Cochrane library were searched through February 2022. Inclusion criteria were: 1) the study examined older adults (&gt;55 years of age) with or susceptible to sarcopenia and free of overt acute or chronic diseases, 2) there was a random allocation of participants to BFR and active control groups, 3) BFR was the sole intervention difference between the groups, and 4) the study provided post-intervention measures of skeletal muscle and physical function which were either the same or comparable to those included in the revised European Working Group on Sarcopenia in Older People (EWGSOP) diagnostic algorithm.

Results: No studies of BFR training in individuals with sarcopenia were found and no study included individuals with FP values below the EWGSOP criteria. However, four studies of BFR training in older adults in which FP was examined were found. BFR training significantly improved the timed up and go (MD = −0.46, z = 2.43, p = 0.02), 30-s chair stand (MD = 2.78, z = 3.72, p &lt; 0.001), and knee extension strength (standardized MD = 0.5, z = 2.3, p = 0.02) in older adults.

Conclusion: No studies of BFR exercise appear to have been performed in patients with or suspected sarcopenia based on latest diagnostic criteria. Despite the absence of such studies, BFR training was found to significantly improve the TUG, 30-s chair stand, and knee extension strength in older adults. Studies examining the effects of BFR in subjects below EWGSOP cut-off points are needed.

Acute hemodynamic responses from Low- load resistance exercise with blood flow restriction in young and older individuals: A Systematic Review and Meta-Analysis of Cross-Over Trials

OBJECTIVE

To summarize the existing evidence on the acute response of low-load (LL) resistance exercise (RE) with blood flow restriction (BFR) on hemodynamic parameters.

DATA SOURCES

MEDLINE (via PubMed), EMBASE (via Scopus), SPORTDiscus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Web of Science, and MedRxiv databases were searched from inception to February 2022.

REVIEW METHODS

Cross-over trials investigating the acute effect of LLRE+BFR vs. passive (no exercise) and active control methods (LLRE or HLRE) on heart rate (HR), systolic (SBP), diastolic (DBP), and mean (MBP) blood pressure responses.

RESULTS

The quality of the studies was assessed using the PEDro scale, risk of bias using the RoB 2.0 tool for cross-over trials, and certainty of the evidence using the GRADE method. A total of 15 randomized cross-over studies with 466 participants were eligible for analyses. Our data showed that LLRE+BFR increases all hemodynamic parameters compared to passive control, but not compared to conventional resistance exercise. Subgroup analysis did not demonstrate any differences between LLRE+BFR and low- (LL) or high-load (HL) resistance exercise protocols. Studies including younger volunteers presented higher chronotropic responses (HR) than those with older volunteers.

CONCLUSIONS

Despite causing notable hemodynamic responses compared to no exercise, the short-term low-load resistance exercise with BFR modulates all hemodynamic parameters HR, SBP, DBP, and MBP, similarly to a conventional resistance exercise protocol, whether at low or high-intensity. The chronotropic response is slightly higher in younger healthy individuals despite the similarity regarding pressure parameters. This article is protected by copyright. All rights reserved.

The need for long-term personalized management of frail CVD patients by rehabilitation and telemonitoring: a framework

Due to advances in cardiovascular medicine and preventive cardiology, patients benefit from a better prognosis, even in case of significant disease burden such as acute and chronic coronary syndromes, advanced valvular heart disease and chronic heart failure. These advances have allowed CVD patients to increase their life expectancy, but on the other hand also experience aging-related syndromes such as frailty. Despite being underrecognized, frailty is a critical, common, and co-existent condition among older CVD patients, leading to exercise intolerance and compromised adherence to cardiovascular rehabilitation. Moreover, frail patients need a different approach for CR and are at very high risk for adverse events, but yet are underrepresented in conventional CR. Fortunately, recent advances have been made in technology, allowing remote monitoring, coaching and supervision of CVD patients in secondary prevention programs with promising benefits. Similarly, we hypothesized that such programs should also be implemented to treat frailty in CVD patients. However, considering frail patients' particular needs and challenges, telerehabilitation interventions should thus be appropriately adapted. Our purpose is to provide, for the first time and based on expert opinions, a framework of how such a cardiac telerehabilitation program could be developed and implemented to manage a prevention and rehabilitation program for CVD patients with frailty.

Relação da Função Pulmonar e da Força Inspiratória com Capacidade Aeróbica e com Prognóstico na Insuficiência Cardíaca

Fundamento

A espirometria é subutilizada na insuficiência cardíaca (IC) e não está claro o grau de associação de cada defeito com a capacidade de exercício e com o prognóstico desses pacientes.

Objetivo

Determinar a relação da %CVF prevista (ppCVF) e do VEF₁/CVF contínuos com: 1) pressão inspiratória máxima (PImáx), fração de ejeção do ventrículo esquerdo (FEVE) e desempenho ao exercício; e 2) prognóstico, para o desfecho composto de morte cardiovascular, transplante cardíaco ou implante de dispositivo de assistência ventricular.

Métodos

Coorte de 111 participantes com IC (estágios AHA C/D) sem pneumopatia; foram submetidos a espirometria, manovacuometria e teste cardiopulmonar máximo. As magnitudes de associação foram verificadas por regressões lineares e de Cox (HR; IC 95%), ajustadas para idade/sexo, e p <0,05 foi considerado significativo.

Resultados

Com idade média 57±12 anos, 60% eram homens, 64% em NYHAIII. A cada aumento de 10% no VEF₁/CVF [β 7% (IC 95%: 3-10)] e no ppCVF [4% (2-6)], foi associado à reserva ventilatória (VRes); no entanto, apenas o ppCVF associado à PImáx [3,8cmH₂O (0,3-7,3)], à fração de ejeção do ventrículo esquerdo (FEVE) [2,1% (0,5-3,8)] e ao VO₂ pico [0,5mL/kg/min (0,1-1,0)], considerando idade/sexo. Em 2,2 anos (média), ocorreram 22 eventos; tanto FEV1/FVC (HR 1,44; IC 95%: 0,97-2,13) quanto ppCVF (HR 1,13; 0,89-1,43) não foram associados ao desfecho. Apenas no subgrupo FEVE ≤50% (n=87, 20 eventos), VEF₁/CVF (HR 1,50; 1,01-2,23), mas não ppCVF, foi associado a risco.

Conclusão

Na IC crônica, ppCVF reduzido associou-se a menor PImáx, FEVE, VRes e VO₂ pico, mas não distinguiu pior prognóstico em 2,2 anos de acompanhamento. Entretanto, VEF₁/CVF associou-se apenas com VRes, e, em participantes com FEVE ≤50%, o VEF₁/CVF reduzido mostrou pior prognóstico proporcional. Portanto, VEF₁/CVF e ppFVC contribuem para melhor fenotipagem de pacientes com IC.

High-intensity interval training versus progressive high-intensity circuit resistance training on endothelial function and cardiorespiratory fitness in heart failure: A preliminary randomized controlled trial

INTRODUCTION

Exercise training is strongly recommended as a therapeutic approach to treat individuals with heart failure. High-intensity exercise training modalities still controversial in this population. The study aims to preliminary assess the consequences of high-intensity exercise training modalities, aerobic interval training (HIIT) and progressive high circuit-resistance training (CRT), on primarily endothelial function and cardiorespiratory fitness, and secondly on muscle strength and physical performance in heart failure patients.

METHODS

This preliminary multicentric randomized controlled trial comprised 23 heart failure patients, aged 56 ± 10 years old, mainly New York Heart Association classification I and II (%), hemodynamically stable, who compromise at least 36 exercise sessions of a randomly assigned intervention (HIIT, CRT or control group). Endothelial function, cardiopulmonary exercise testing, muscle strength and physical performance were completed at baseline and post-intervention.

RESULTS

Although no effects on endothelial function; both HIIT and CRT modalities were able to produce a positive effect on [Formula: see text] peak (HIIT = +2.1±6.5, CRT = +3.0±4.2 and control group = -0.1± 5.3 mL/kg/min, time*group p-value<0,05) and METs (HIIT = +0.6±1.8, CRT = +0.9±1.2 and control group = 0±1.6, time*group p-value<0,05). Only HIIT increased isokinetic torque peak (HIIT = +8.8±55.8, CRT = 0.0±60.7 and control group = 1.6±57.6 Nm) matched p-value<0,05. Regarding the physical performance, the CRT modality reduced chair stand test completion time (HIIT = -0.7±3.1, CRT = -3.3±3.2 and control group = -0.3±2.5 s, matched p-value<0,05 and HIIT improved global physical performance(time*group p<0,05).

CONCLUSION

This preliminary study trends to indicate for the first time that high-intensity interval training promotes a jointly superior effect compared to progressive high intensity circuit-resistance training by improving cardiorespiratory fitness, muscular strength, and physical performance. Further research with larger cohort is necessary.

CLINICAL TRIAL REGISTRATION NUMBER

ReBEC RBR-668c8v.

Adjunctive inspiratory muscle training for patients with COVID-19 (COVIDIMT): protocol for randomised controlled double-blind trial

INTRODUCTION

A significant number of patients with COVID-19 may experience dyspnoea, anxiety, depression, pain, fatigue and physical impairment symptoms, raising the need for a multidisciplinary rehabilitation approach, especially for those with advanced age, obesity, comorbidities and organ failure. Traditional pulmonary rehabilitation (PR), including exercise training, psychosocial counselling and education, has been employed to improve pulmonary function, exercise capacity and quality of life in patients with COVID-19. However, the effects of inspiratory muscle training (IMT) in PR programmes remain unclear. This study aimed to determine whether the addition of a supervised IMT in a PR is more effective than PR itself in improving dyspnoea, health-related quality of life and exercise capacity in symptomatic patients with post-COVID-19.

METHODS AND ANALYSIS

This parallel-group, assessor-blinded randomised controlled trial, powered for superiority, aimed to assess exercise capacity as the primary outcome. A total of 138 are being recruited at two PR centres in Brazil. Following baseline testing, participants will be randomised using concealed allocation, to receive either (1) standard PR with sham IMT or (2) standard PR added to IMT. Treatment effects or differences between the outcomes (at baseline, after 8 and 16 weeks, and after 6 months) of the study groups will be analysed using an ordinary two-way analysis of variance.

ETHICS AND DISSEMINATION

This trial was approved by the Brazilian National Ethics Committee and obtained approval on 7 October 2020 (document number 4324069). The findings will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT04595097.

Acute and Time-Course Effects of Osteopathic Manipulative Treatment on Vascular and Autonomic Function in Patients With Heart Failure: A Randomized Trial

OBJECTIVE

The purposed of this study was to valuate the effect of osteopathic manipulative treatment (OMT) on flow-mediated dilation and heart rate variability of patients with heart failure.

BACKGROUND

Osteopathic manipulative treatment modulates both the vascular and autonomic nervous system (ANS) in healthy volunteers. However, the acute and time-course effects of the OMT on patients with an overactive ANS remain unclear.

METHODS

This randomized controlled trial study included 20 patients with heart failure aged 50 to 60 years, allocated to a single session of OMT (base of the skull, retromaxillary region, heart, and thoracic duct) or sham. Flow-mediated dilation (FMD) at the brachial artery, hemodynamic measures, and heart rate variability were assessed in 3 periods (baseline, immediately after the intervention, and after 15 minutes). Multivariate analysis of variance procedure was used to compare intervention and periods.

RESULTS

The OMT group had a greater FMD modulation compared with the sham (FMD,% =  9.5 vs. -5.6, 95% confidence interval (CI): [6.6, -12.35] vs. [-14.25, 2.8]; p = 0.001) and grater peak diameter (PD, mm =  0.77 vs -0.16 mm, 95% CI: [0.31,-1.24] vs [-0.63, 0.29]; P =  0.001), suggesting an important acute and time-course vascular effect from OMT. We also found some relevant heart rate variability modulation after 15 minutes from OMT: high frequency (HF, ms² = 295 vs -354, 95% CI: [144.2, -769]; P = .001) and low frequency (LF, ms²) = 670 vs 775, 95% CI: [-98, 3591]; P = .001), suggesting a time-course ANS modulation after OMT.

CONCLUSIONS

Osteopathic manipulative treatment was effective at increasing brachial blood flow and stimulating the vagal system in patients with heart failure. Moreover, vascular changes seem to precede the autonomic modulation.

Moderate-intensity exercise with blood flow restriction on cardiopulmonary kinetics and efficiency during a subsequent high-intensity exercise in young women: A cross-sectional study

Blood flow restriction (BFR) training applied prior to a subsequent exercise has been used as a method to induce changes in oxygen uptake pulmonary kinetics (O2P) and exercise performance. However, the effects of a moderate-intensity training associated with BFR on a subsequent high-intensity exercise on O2P and cardiac output (QT) kinetics, exercise tolerance, and efficiency remain unknown.This prospective physiologic study was performed at the Exercise Physiology Lab, University of Brasilia. Ten healthy females (mean ± SD values: age = 21.3 ± 2.2 years; height = 1.6 ± 0.07 m, and weight = 55.6 ± 8.8 kg) underwent moderate-intensity training associated with or without BFR for 6 minutes prior to a maximal high-intensity exercise bout. O2P, heart rate, and QT kinetics and gross efficiency were obtained during the high-intensity constant workload exercise test.No differences were observed in O2P, heart rate, and QT kinetics in the subsequent high-intensity exercise following BFR training. However, exercise tolerance and gross efficiency were significantly greater after BFR (220 ± 45 vs 136 ± 30 seconds; P < .05, and 32.8 ± 6.3 vs 27.1 ± 5.4%; P < .05, respectively), which also resulted in lower oxygen cost (1382 ± 227 vs 1695 ± 305 mL min-1).We concluded that moderate-intensity BFR training implemented prior to a high-intensity protocol did not accelerate subsequent O2P and QT kinetics, but it has the potential to improve both exercise tolerance and work efficiency at high workloads.

Dataset and species aggregation method applied to food-web models in the Northern Ionian Sea (Central Mediterranean Sea)

The ecological roles of the species in the food web are studied through the Ecopath with Ecosim modelling approach. In this modelling approach, the food web is described by means of functional groups, each representing a species, a life stage of a species, or a group of species with similar trophic, ecological and physiological features. Links between the groups are formally described by a set of linear equations, informed with ecological and fishing data. Here, the data input collected to implement 3 Ecopath models in the Northern Ionian Sea (Central Mediterranean Sea) from 1995 to 2015 are reported. This dataset applied to study the ecological roles of the demersal Chondrichthyes in the study area could be useful to explore different fishing management scenarios. A large dataset of over 300 taxa is shown detailing the ecological inputs, such as Biomass (kg km-2), Production and Consumption rates (y-1), Diet information (weight in %), and fishing data represented by Landings and Discards (t km-2 y-1). In particular, the fishery data described the catches of trawls, longlines, passive nets, other gears and purse seine. In addition, a description of the aggregation method of the species is shown.

Maximal Dynamic Inspiratory Pressure Evaluation in Heart Failure: A Comprehensive Reliability and Agreement Study

OBJECTIVE

The purpose of this study was to analyze the reliability (interrater and intrarater) and agreement (repeatability and reproducibility) properties of tapered flow resistive loading (TFRL) measures in patients with heart failure (HF).

METHODS

For this cross-sectional study, participants were recruited from the cardiopulmonary rehabilitation program at the University of Brasilia from July 2015 to July 2016. All patients participated in the study, and 10 were randomly chosen for intrarater and interrater reliability testing. The 124 participants with HF (75% men) were 57.6 (SD = 1.81) years old and had a mean left ventricular ejection fraction of 38.9% (SD = 15%) and a peak oxygen consumption of 13.05 (SD = 5.3) mL·kg·min-1. The main outcome measures were the maximal inspiratory pressure (MIP) measured with a standard manovacuometer (SM) and the MIP and maximal dynamic inspiratory pressure (S-Index) obtained with TFRL. The S-Index reliability (interrater and intrarater) was examined by 2 evaluators, the S-Index repeatability was examined with 10 repetitions, and the reproducibility of the MIP and S-Index was measured with SM and TFRL, respectively.

RESULTS

The reliability analysis revealed high S-Index interrater and intrarater reliability values (intraclass correlation coefficients [ICCs] of 0.89 [95% CI = 0.58-0.98] and 0.97 [95% CI = 0.89-0.99], respectively). Repeatability analyses revealed that 8 maneuvers were required to reach the maximum S-Index in 75.81% (95% CI = 68.27-83.34) of the population. The reproducibility of TFRL measures (S-Index = 68.8 [SD = 32.8] cm H2O; MIP = 66 [SD = 32.3] cm H2O) was slightly lower than that of the SM measurement (MIP = 70.1 [SD = 35.9] cm H2O).

CONCLUSIONS

The TFRL device provided a reliable intrarater and interrater S-Index measure in patients with HF and had acceptable repeatability, requiring 8 maneuvers to produce a stable S-Index measure. The reproducibilities of the S-Index, MIP obtained with SM, and MIP obtained with TRFL were similar.

IMPACT

TRFL is a feasible method to assess both MIP and the S-index as measures of inspiratory muscle strength in patients with HF and can be used for inspiratory muscle training, making the combined testing and training capabilities important in both clinical research and the management of patients with HF.

Functional Resistance Training Superiority Over Conventional Training in Metabolic Syndrome: A Randomized Clinical Trial

Metabolic syndrome (MetS) is a growing epidemic related with higher values of blood pressure (BP) and autonomic dysfunction. Scientific evidence has been indicating that functional resistance training (FRT) is superior over conventional (CRT) for muscle fatigue and pain, yet its effects on autonomic modulation (AM), BP and heart rate in MetS are unclear. We theorized that FRT can be superior to CRT in MetS patients because of larger muscle activation. This study compares FRT and CRT on AM, blood pressure, heart rate and muscle strength. Thirty-eight sex and age matched individuals (40 to 60 years) were randomized for FRT or CRT, with training intensity varying gradually from 30%-100% of one maximal repetition test (1MR), 3 times/week for 30 sessions. All outcomes were evaluated at baseline and post training. AM was assessed by heart rate variability (mean RR, RMSSD, SDNN, LF, HF, TINN, RRtri, SD1 and SD2). BP (mmHg) was obtained by cuff measures. Muscle strength was assessed by 1MR. An increase in cardiac parasympathetic activity was observed in individuals allocated to FRT in comparison to CRT group (RMSSD ∆40%; SD1 ∆39%; and HF _ms ² ∆80%). Moreover, just FRT was capable of reducing BP post intervention (SBP from 129.21 ± 19.02 to 118.94 ± 14.14 mmHg, p < .009,/d/ = 0.49; DBP from 85.26 ± 11.48 to 77.76 ± 8.93 mmHg, p < .01,/d/ = 0.51). Both groups had a similar increase in muscle strength and no changes between HR. Progressive FRT was more beneficial to CRT regarding AM, increasing vagal activity, and reducing blood pressure in MetS individuals.

Reliability of skeletal muscle ultrasound in critically ill trauma patients

Objective

To evaluate the safety and feasibility of the ultrasound assessment of quadriceps in the emergency setting. To assess the intra- and interrater reliability for the acquisition and analysis of ultrasound images of muscle thickness and echogenicity in critically ill trauma patients between health professionals with different levels of expertise.

Methods

Diagnostic accuracy study. Two examiners (expert and novice) acquired ultrasound images from ten patients; an experienced, blinded analyst quantified the images. In a separate group of ten patients, two analysts (expert and novice) quantified quadriceps muscle thickness and echogenicity (square or trace method) from images acquired by one examiner.

Results

Excellent reliability was found for image acquisition and analysis (intraclass correlation coefficients > 0.987; p < 0.001). The standard error of the measurement values ranged from 0.01 - 0.06cm for muscle thickness and from 0.75 - 2.04 arbitrary units for muscle echogenicity. The coefficients of variation were < 6% for thickness and echogenicity. The echogenicity values were higher when using the square technique than when using the tracing technique (p = 0.003).

Conclusion

Ultrasound is safe, feasible, and reliable for muscle assessment in critically ill trauma patients, regardless of the assessor's level of expertise.

Current insights of inspiratory muscle training on the cardiovascular system: a systematic review with meta-analysis

Background: Cardiorespiratory limitation is a common hallmark of cardiovascular disease which is a key component of pharmacological and exercise treatments. More recently, inspiratory muscle training (IMT) is becoming an effective complementary treatment with positive effects on muscle strength and exercise capacity. We assessed the effectiveness of IMT on the cardiovascular system through autonomic function modulation via heart rate variability and arterial blood pressure.

Methods: Randomized controlled trials (RCTs) were identified from searches of The Cochrane Library, MEDLINE and EMBASE to November 2018. Citations, conference proceedings and previous reviews were included without population restriction, comparing IMT intervention to no treatment, placebo or active control.

Results: We identified 10 RCTs involving 267 subjects (mean age range 51–71 years). IMT programs targeted maximum inspiratory pressure (MIP) and cardiovascular outcomes, using low (n=6) and moderate to high intensity (n=4) protocols, but the protocols varied considerably (duration: 1–12 weeks, frequency: 3–14 times/week, time: 10–30 mins). An overall increase of the MIP (cmH₂O) was observed (−27.57 95% CI −18.48, −37.45, I²=64%), according to weighted mean difference (95%CI), and was accompanied by a reduction of the low to high frequency ratio (−0.72 95% CI−1.40, −0.05, I²=50%). In a subgroup analysis, low- and moderate-intensity IMT treatment was associated with a reduction of the heart rate (HR) (−7.59 95% CI −13.96, −1.22 bpm, I²=0%) and diastolic blood pressure (DBP) (−8.29 [−11.64, −4.94 mmHg], I²=0%), respectively.

Conclusion: IMT is an effective treatment for inspiratory muscle weakness in several populations and could be considered as a complementary treatment to improve the cardiovascular system, mainly HR and DBP. Further research is required to better understand the above findings.

Resistance exercise enhances oxygen uptake without worsening cardiac function in patients with systolic heart failure: a systematic review and meta-analysis

Recent literature suggests that resistance training (RT) improves peak oxygen uptake ([Formula: see text] peak), similarly to aerobic exercise (AE) in patients with heart failure (HF), but its effect on cardiac remodeling is controversial. Thus, we examined the effects of RT and AE on [Formula: see text] peak and cardiac remodeling in patients with heart failure (HF) via a systematic review and meta-analysis. MEDLINE, EMBASE, Cochrane Library and CINAHL, AMEDEO and PEDro databases search were extracted study characteristics, exercise type, and ventricular outcomes. The main outcomes were [Formula: see text] peak (ml kg^-1 min^-1), LVEF (%) and LVEDV (mL). Fifty-nine RCTs were included. RT produced a greater increase in [Formula: see text] peak (3.57 ml kg^-1 min^-1, P < 0.00001, I ² = 0%) compared to AE (2.63 ml kg^-1 min^-1, P < 0.00001, I ² = 58%) while combined RT and AE produced a 2.48 ml kg^-1 min^-1 increase in [Formula: see text]; I ² = 69%) compared to control group. Comparison among the three forms of exercise revealed similar effects on [Formula: see text] peak (P = 0.84 and 1.00, respectively; I ² = 0%). AE was associated with a greater gain in LVEF (3.15%; P < 0.00001, I ² = 17%) compared to RT alone or combined exercise which produced similar gains compared to control groups. Subgroup analysis revealed that AE reduced LVEDV (- 10.21 ml; P = 0.007, I ² = 0%), while RT and combined RT and AE had no effect on LVEDV compared with control participants. RT results in a greater gain in [Formula: see text] peak, and induces no deleterious effects on cardiac function in HF patients.

Impact of Passive Leg Cycling in Persons With Spinal Cord Injury: A Systematic Review

Background: Passive leg cycling is an important clinical tool available for rehabilitation after spinal cord injury (SCI). Passive cycling can be used to derive exercise-related benefits in patients with poor motor control. There have been a number of studies examining the effects of passive cycling on a variety of outcomes. There is need for a systematic assessment of the cycling parameters and the associated clinical changes in cardiovascular, neuromuscular, and musculoskeletal outcomes after passive cycling. Objectives: To assess the effectiveness of passive leg cycling interventions on cardiovascular, neuromuscular, and musculoskeletal outcomes post SCI, and to describe intensity, duration, and type of passive leg cycling post SCI. Methods: PRISMA guided systematic review of literature based on searches in the following databases: PubMed/MEDLINE, PEDro, EMBASE, Cochrane Library, and Google Scholar. Peer-reviewed publications that were written in English were included if they described the effects of a single session or multiple sessions of passive leg cycling in persons post SCI. Results: Eleven papers were included: two were randomized controlled trials (RCTs), one was a crossover trial, and the rest were pre-post single-group designs. Three studies (including two RCTs) reported statistically significant benefits of multiple sessions of passive cycling on leg blood flow velocity, spasticity, reflex excitability and joint range of motion, and markers of muscle hypertrophy. About half of the single session studies showed statistically significant improvement in acute responses. Conclusion: Multiple sessions of passive leg cycling showed benefits in three categories - cardiovascular, musculoskeletal, and neurological - with medium to large effect sizes.

Neuromuscular electrical stimulation combined with exercise decreases duration of mechanical ventilation in ICU patients: A randomized controlled trial

BACKGROUND

Early mobilization can be employed to minimize the duration of intensive care. However, a protocol combining neuromuscular electrical stimulation (NMES) with early mobilization has not yet been tested in ICU patients. Our aim was to assess the efficacy of NMES, exercise (EX), and combined therapy (NMES + EX) on duration of mechanical ventilation (MV) in critically ill patients.

METHODS

The participants in this randomized double-blind trial were prospectively recruited within 24 hours following admission to the intensive care unit of a tertiary hospital. Eligible patients had 18 years of age or older; MV for less than 72 hours; and no known neuromuscular disease. Computer-generated permuted block randomization was used to assign patients to NMES, EX, NMES + EX, or standard care (control group). The main endpoint was duration of MV. Clinical characteristics were also evaluated and intention to treat analysis was employed.

RESULTS

One hundred forty-four patients were assessed for eligibility to participate in the trial, 51 of whom were enrolled and randomly allocated into four groups: 11 patients in the NMES group, 13 in the EX group, 12 in the NMES + EX group, and 15 in the control group (CG). Duration of MV (days) was significantly shorter in the combined therapy (5.7 ± 1.1) and NMEN (9.0 ± 7.0) groups in comparison to CG (14.8 ± 5.4).

CONCLUSIONS

NMES + EX consisting of NMES and active EXs was well tolerated and resulted in shorter duration of MV in comparison to standard care or isolated therapy (NMES or EX alone).

Brazilian version of the Functional Status Score for the ICU: translation and cross-cultural adaptation

Objective

The aim of the present study was to translate and cross-culturally adapt the Functional Status Score for the intensive care unit (FSS-ICU) into Brazilian Portuguese.

Methods

This study consisted of the following steps: translation (performed by two independent translators), synthesis of the initial translation, back-translation (by two independent translators who were unaware of the original FSS-ICU), and testing to evaluate the target audience's understanding. An Expert Committee supervised all steps and was responsible for the modifications made throughout the process and the final translated version.

Results

The testing phase included two experienced physiotherapists who assessed a total of 30 critical care patients (mean FSS-ICU score = 25 ± 6). As the physiotherapists did not report any uncertainties or problems with interpretation affecting their performance, no additional adjustments were made to the Brazilian Portuguese version after the testing phase. Good interobserver reliability between the two assessors was obtained for each of the 5 FSS-ICU tasks and for the total FSS-ICU score (intraclass correlation coefficients ranged from 0.88 to 0.91).

Conclusion

The adapted version of the FSS-ICU in Brazilian Portuguese was easy to understand and apply in an intensive care unit environment.

Association between inspiratory muscle weakness and slowed oxygen uptake kinetics in patients with chronic obstructive pulmonary disease

Patients with chronic obstructive pulmonary disease (COPD) may have poor inspiratory muscle function, which reduces minute and alveolar ventilation, leading to increased hypoxemia and slow pulmonary oxygen uptake kinetics. However, little is known about the effect of inspiratory muscle weakness (IMW) on oxygen uptake kinetics in patients with COPD. Thus, we tested the hypothesis that COPD patients with IMW have slowed oxygen uptake kinetics. An observational study was conducted that included COPD patients with moderate to severe airflow limitation and a history of intolerance to exercise. Participants were divided into 2 groups: (IMW+; n = 22) (IMW–; n = 23) of muscle weakness. The maximal inspiratory, expiratory, and sustained inspiratory strength as well as the maximal endurance of the inspiratory muscles were lower in IMW+ patients (36 ± 9.5 cm H2O; 52 ± 14 cm H2O; 20 ± 6.5 cm H2O; 94 ± 84 s, respectively) than in IMW– patients (88 ± 12 cm H2O; 97 ± 28 cm H2O; 82.5 ± 54 cm H2O; 559 ± 92 s, respectively; p < 0.05). Moreover, the 6-min walk test and peak oxygen uptake were reduced in the IMW+ patients. During the constant work test, oxygen uptake kinetics were slowed in the IMW+ compared with IMW– patients (88 ± 29 vs 61 ± 18 s, p < 0.05). Our findings demonstrate that inspiratory muscle weakness in COPD is associated with slowed oxygen uptake kinetics, and thus, reduced functional capacity.

Neuromuscular electrophysiological disorders and muscle atrophy in mechanically-ventilated traumatic brain injury patients: New insights from a prospective observational study

PURPOSE

It is unclear whether the muscular changes in mechanically-ventilated traumatic brain injury patients (TBI) are only associated with disuse or additionally to neuromuscular electrophysiological disorders (NED). The correlation between muscle atrophy and NED may affect functional outcomes and rehabilitation programs significantly.

MATERIAL AND METHODS

An observational study was performed to investigate the presence of NED and muscle atrophy in TBI patients undergoing mechanical ventilation. NED was diagnosed by the stimulus electrodiagnosis test when chronaxie was ≥1000μs. The muscle structure (thickness and echogenicity) was assessed by B-mode ultrasound. Tibialis anterior (TA), rectus femoris (RF), and biceps brachialis (BB) muscles were analyzed. Patients were followed from the first day of admission in the intensive care unit (ICU) to the fourteenth day.

RESULTS

Twenty-two patients were analyzed. An increase of 48% in NED from day 1 to day 14 was detected in TA (p=0.004). All muscles presented a significant decrease in thickness (~18%, p<0.05), but echogenicity increased only in TA (19%), p<0.01 and RF (23%), p<0.01.

CONCLUSIONS

Mechanically-ventilated patients with TBI developed NED in addition to changes in muscle structure during their stay in the ICU.

Maximal Inspiratory Pressure: Does the Choice of Reference Values Actually Matter?

BACKGROUND

Single-point measurements of maximal inspiratory pressure (MIP) are frequently used to suggest muscle weakness in clinical practice. Although there is a large variability in "mean" predicted MIP depending on the chosen reference values, it remains unclear whether those discrepancies actually impact on the prevalence of weakness, that is, MIP below the lower limit of normal.

METHODS

A total of 1,729 subjects (50.1% men, aged 20 to 94 years) who underwent MIP measurements in a clinical laboratory comprised the study group. MIP was predicted according to the most frequently cited regression equations as of August 2015. Pretest probability of weakness was defined by a cluster of clinical and physiologic variables.

RESULTS

Prevalence of weakness ranged from 33.4 to 66.9%. Set 2 equations agreed well in indicating weakness (κ [95% CI] ranging from 0.81 [0.79-0.83] to 0.83 [0.81-0.85]; P < .01). There was closer agreement between higher pretest probability of weakness and low MIP according to set 2 equations compared with set 1 equations. Thus, a significant fraction of subjects with abnormal MIP according to set 1 equations but preserved MIP according to set 2 equations had higher pretest probability of weakness (P < .05).

CONCLUSIONS

The choice of MIP reference values strongly impacts on the prevalence of weakness. Some specific equations relate better to clinical and physiologic indicators of weakness, suggesting that they might be particularly useful to screen subjects for advanced respiratory neuromuscular assessment.

Spontaneous breathing trial in T-tube negatively impact on autonomic modulation of heart rate compared with pressure support in critically ill patients

INTRODUCTION

Spontaneous breathing with a conventional T-piece (TT) connected to the tracheal tube orotraqueal has been frequently used in clinical setting to weaning of mechanical ventilation (MV), when compared with pressure support ventilation (PSV). However, the acute effects of spontaneous breathing with TT versus PSV on autonomic function assessed through heart rate variability (HRV) have not been fully elucidated.

OBJECTIVE

The purpose of this study was to examine the acute effects of spontaneous breathing in TT vs PSV in critically ill patients.

METHOD

Twenty-one patients who had received MV for ≥ 48 h and who met the study inclusion criteria for weaning were assessed. Eligible patients were randomized to TT and PSV. Cardiorespiratory responses (respiratory rate -ƒ, tidal volume-V_T , mean blood pressure (MBP) and diastolic blood pressure (DBP), end tidal dioxide carbone (P_ET CO₂ ), peripheral oxygen saturation (SpO₂ ) and HRV indices in frequency domain (low-LF, high frequency (HF) and LF/HF ratio were evaluated.

RESULTS

TT increased ƒ (20 ± 5 vs 25 ± 4 breaths/min, P<0.05), MBP (90 ± 14 vs 94 ± 18 mmHg, P<0.05), HR (90 ± 17 vs 96 ± 12 beats/min, P<0.05), P_ET CO₂ (33 ± 8 vs 48 ± 10 mmHg, P<0.05) and reduced SpO₂ (98 ± 1.6 vs 96 ± 1.6%, P<0.05). In addition, LF increased (47 ± 18 vs 38 ± 12 nu, P<0.05) and HF reduced (29 ± 13 vs 32 ± 16 nu, P<0.05), resulting in higher LF/HF ratio (1.62 ± 2 vs 1.18 ± 1, P<0.05) during TT. Conversely, V_T increased with PSV (0.58 ± 0.16 vs 0.50 ± 0.15 L, P<0.05) compared with TT.

CONCLUSION

Acute effects of TT mode may be closely linked to cardiorespiratory mismatches and cardiac autonomic imbalance in critically ill patients.

Hemodynamic Effects Induced by Transcutaneous Electrical Nerve Stimulation in Apparently Healthy Individuals: A Systematic Review With Meta-Analysis

OBJECTIVE

To determine the immediate effects of transcutaneous electrical nerve stimulation (TENS) on heart rate, systolic blood pressure (SBP), and diastolic blood pressure (DBP) in apparently healthy adults (age ≥18y).

DATA SOURCES

The Cochrane Library (online version 2014), PubMed (1962-2014), EMBASE (1980-2014), and LILACS (1980-2014) electronic databases were searched.

STUDY SELECTION

Randomized controlled trials were included when TENS was administered noninvasively with surface electrodes during rest, and the effect of TENS was compared with that of control or placebo TENS. A sensitive search strategy for identifying randomized controlled trials was used by 2 independent reviewers. The initial search led to the identification of 432 studies, of which 5 articles met the eligibility criteria.

DATA EXTRACTION

Two independent reviewers extracted data from the selected studies. Quality was evaluated using the PEDro scale. Mean differences or standardized mean differences in outcomes were calculated.

DATA SYNTHESIS

Five eligible articles involved a total of 142 apparently healthy individuals. Four studies used high-frequency TENS and 3 used low-frequency TENS and evaluated the effect on SBP. Three studies using high-frequency TENS and 2 using low-frequency TENS evaluated the effect on DBP. Three studies using high-frequency TENS and 1 study using low-frequency TENS evaluated the effect on heart rate. A statistically significant reduction in SBP (-3.00mmHg; 95% confidence interval [CI], -5.02 to -0.98; P=.004) was found using low-frequency TENS. A statistically significant reduction in DBP (-1.04mmHg; 95% CI, -2.77 to -0.03; I(2)=61%; P=.04) and in heart rate (-2.55beats/min; 95% CI, -4.31 to -0.78; I(2)=86%; P=.005]) was found using both frequencies. The median value on the PEDro scale was 7 (range, 4-8).

CONCLUSIONS

TENS seems to promote a discrete reduction in SBP, DBP, and heart rate in apparently healthy individuals.

Oxidative damage induced by cigarette smoke exposure in mice: impact on lung tissue and diaphragm muscle

OBJECTIVE

To evaluate oxidative damage (lipid oxidation, protein oxidation, thiobarbituric acid-reactive substances [TBARS], and carbonylation) and inflammation (expression of phosphorylated AMP-activated protein kinase and mammalian target of rapamycin [p-AMPK and p-mTOR, respectively]) in the lung parenchyma and diaphragm muscles of male C57BL-6 mice exposed to cigarette smoke (CS) for 7, 15, 30, 45, or 60 days.

METHODS

Thirty-six male C57BL-6 mice were divided into six groups (n = 6/group): a control group; and five groups exposed to CS for 7, 15, 30, 45, and 60 days, respectively.

RESULTS

Compared with control mice, CS-exposed mice presented lower body weights at 30 days. In CS-exposed mice (compared with control mice), the greatest differences (increases) in TBARS levels were observed on day 7 in diaphragm-muscle, compared with day 45 in lung tissue; the greatest differences (increases) in carbonyl levels were observed on day 7 in both tissue types; and sulfhydryl levels were lower, in both tissue types, at all time points. In lung tissue and diaphragm muscle, p-AMPK expression exhibited behavior similar to that of TBARS. Expression of p-mTOR was higher than the control value on days 7 and 15 in lung tissue, as it was on day 45 in diaphragm muscle.

CONCLUSION

Our data demonstrate that CS exposure produces oxidative damage, not only in lung tissue but also (primarily) in muscle tissue, having an additional effect on respiratory muscle, as is frequently observed in smokers with COPD.

Transcutaneous Electrical Nerve Stimulation Improves Exercise Tolerance in Healthy Subjects

Transcutaneous electrical nerve stimulation (TENS) increases peripheral blood flow by attenuation of the muscle metaboreflex, improving oxygen supply to working muscles. We tested the hypothesis that application of TENS at ganglion improves exercise performance. 11 subjects underwent constant-work rate tests (CWR) to the limit of tolerance (Tlim) while receiving TENS or placebo. Oxygen uptake (V.O2), carbon dioxide (V.CO2), minute ventilation (V.E), ventilatory equivalent (V.E/V.CO2), heart rate (HR) and oxygen pulse (V.O2/HR) were analyzed at isotime separated by percentile and Tlim. V.O2 was lower and V.CO2 was higher at 100% of isotime during TENS, while there were no differences in V.E and V.E/V.CO2. HR was lower during exercise with TENS, and V.O2/HR increased at peak exercise (17.96±1.9 vs. 20.38±1 ml/min/bpm, P<0.05). TENS increased mechanical efficiency at isotime and Tlim (4.10±0.50 vs. 3.39±0.52%, P<0.05 and 3.95±0.67 vs. 3.77±0.45%, P<0.05) and exercise tolerance compared to P-TENS (390±41 vs. 321±41 s; P<0.05). Our data shows that the application of TENS can potentially increase exercise tolerance and oxygen supply in healthy subjects.

Low-level laser therapy associated with high intensity resistance training on cardiac autonomic control of heart rate and skeletal muscle remodeling in wistar rats

BACKGROUND AND OBJECTIVE

Phototherapy plus dynamic exercise can enhance physical performance and improve health. The aim of our study was to evaluate the effect of low-level laser therapy (LLLT) associated with high intensity resistance training (HIT) on cardiac autonomic and muscle metabolic responses in rats.

STUDY DESIGN/MATERIALS AND METHODS

Forty Wistar rats were randomized into 4 groups: sedentary control (CG), HIT, LLLT and HIT + LLLT. HIT was performed 3 times/week for 8 weeks with loads attached to the tail of the animal. The load was gradually increased by 10% of body mass until reaching a maximal overload. For LLLT, irradiation parameters applied to the tibialis anterior (TA) muscle were as follows: infrared laser (780 nm), power of 15 mW for 10 seconds, leading to an irradiance of 37.5 mW/cm(2), energy of 0.15 J per point and fluency of 3.8 J/cm(2). Blood lactate (BL), matrix metalloproteinase gelatinase A (MMP(-2)) gene expression and heart rate variability (HRV) indices were performed.

RESULTS

BL significantly increased after 8-weeks for HIT, LLLT and HIT + LLLT groups. However, peak lactate when normalized by maximal load was significantly reduced for both HIT and HIT + LLLT groups (P<0.05). MMP-2 in the active form was significantly increased after HIT, LLLT and HIT + LLLT compared tom the CG (P<0.05). There was a significant reduction in low frequency [LF (ms(2))] and increase in high frequency [HF (un)] and HF (ms(2))] for the HIT, LLLT and HIT + LLLT groups compared with the CG (P < 0.05). However, the LF/HF ratio was further reduced in the LLLT and HIT + LLLT groups compared to the CG and HIT group (P < 0.05).

CONCLUSION

These results provide evidence for the positive benefits of LLLT and HIT with respect to enhanced muscle metabolic and cardiac autonomic function in Wistar rats.

Interferential electrical stimulation improves peripheral vasodilatation in healthy individuals

BACKGROUND

Interferential electrical stimulation (IES), which may be linked to greater penetration of deep tissue, may restore blood flow by sympathetic nervous modulation; however, studies have found no association between the frequency and duration of the application and blood flow. We hypothesized that 30 min of IES applied to the ganglion stellate region might improve blood flow redistribution.

OBJECTIVES

The purpose of this study was to determine the effect of IES on metaboreflex activation in healthy individuals.

METHOD

Interferential electrical stimulation or a placebo stimulus (same protocol without electrical output) was applied to the stellate ganglion region in eleven healthy subjects (age 25±1.3 years) prior to exercise. Mean blood pressure (MBP), heart rate (HR), calf blood flow (CBF) and calf vascular resistance (CVR) were measured throughout exercise protocols (submaximal static handgrip exercise) and with recovery periods with or without postexercise circulatory occlusion (PECO+ and PECO -, respectively). Muscle metaboreflex control of calf vascular resistance was estimated by subtracting the area under the curve when circulation was occluded from the area under the curve from the AUC without circulatory occlusion.

RESULTS

At peak exercise, increases in mean blood pressure were attenuated by IES (p<0.05), and the effect persisted under both the PECO+ and PECO- treatments. IES promoted higher CBF and lower CVR during exercise and recovery. Likewise, IES induced a reduction in the estimated muscle metaboreflex control (placebo, 21±5 units vs. IES, 6±3, p<0.01).

CONCLUSION

Acute application of IES prior to exercise attenuates the increase in blood pressure and vasoconstriction during exercise and metaboreflex activation in healthy subjects.

Sympathetic ganglion transcutaneous electrical nerve stimulation after coronary artery bypass graft surgery improves femoral blood flow and exercise tolerance

We tested the hypothesis that transcutaneous electrical nerve stimulation (TENS) over the stellate ganglion region would reduce sympathetic overstimulation and improve femoral blood flow (FBF) after coronary artery bypass graft surgery. Thirty-eight patients (20 men, 24 New York Heart Association class III-IV) were randomized to 5-day postoperative TENS (n = 20; 4 times/day; 30 min/session) or sham TENS (n = 18) applied to the posterior cervical region (C7-T4). Sympathetic nervous system was stimulated by the cold pressor test, with FBF being measured by ultrasound Doppler. Femoral vascular conductance (FVC) was calculated as FBF/mean arterial pressure (MAP). Six-min walking distance established patients' functional capacity. Before and after the intervention periods, pain scores, opiate requirements, and circulating β-endorphin levels were determined. As expected, preoperative MAP increased and FBF and FVC decreased during the cold pressor test. Sham TENS had no significant effect on these variables (P > 0.05). In contrast, MAP decreased in the TENS group (125 ± 12 vs. 112 ± 10 mmHg). This finding, in association with a consistent increase in FBF (95 ± 5 vs. 145 ± 14 ml/min), led to significant improvements in FVC (P < 0.01). Moreover, 6-min walking distance improved only with TENS (postsurgery-presurgery = 35 ± 12 vs. 6 ± 10 m; P < 0.01). TENS was associated with lesser postoperative pain and opiate requirements but greater circulating β-endorphin levels (P < 0.05). In conclusion, stellate ganglion TENS after coronary artery bypass graft surgery positively impacted on limb blood flow during a sympathetic stimulation maneuver, a beneficial effect associated with improved clinical and functional outcomes.