The use of ultrasonography as a tool to evaluate the quadriceps muscle in patients with chronic obstructive pulmonary disease: a systematic review

The aim of this review is to understand the feasibility and potential clinical utility of US in measurements of the quadriceps muscles in patients with COPD. A total of 217 studies were identified and after applying the inclusion criteria, 12 were selected. The data were systematically searched by two independent reviewers. Of the included articles, five evaluated the maximal voluntary contraction of the quadriceps muscle and the Transverse Section Area (TSA) measured by US, of these, 4 found a remarkably reduced strength in COPD and in one article, it was described that this reduction occurs in all grades of the disease. Moreover, the greater the thickness of the quadriceps, the greater the maximum voluntary contraction of this musculature, however, the TSA is reduced in these patients when compared to healthy individuals. Thus, it is suggested that the AST, evaluated by US, can be used to assess the presence and/or severity of musculoskeletal dysfunction in these patients. The sonographic evaluation of the quadriceps in patients with COPD may provide a safe, effective, low-cost, reliable and reproducible evaluation, allowing the identification and monitoring of peripheral muscle dysfunction in this population, even when compared with other strategies.

Mechanism of Dyspnea during Exercise in Children with Corrected Congenital Heart Disease

This study will evaluate cardiorespiratory and peripheral muscle function and their relationship with subjective dyspnea threshold after the surgical correction of congenital heart disease in children. Thirteen children with surgically repaired congenital heart disease were recruited. Each participant performed an incremental exercise test on a cycle ergometer until exhaustion. Gas exchanges were continuously sampled to measure the maximal aerobic parameters and ventilatory thresholds. The functional capacity of the subjects was assessed with a 6 min walk test. At the end of the exercise test, isokinetic Cybex Norm was used to evaluate the strength and endurance of the knee extensor muscle in the leg. Dyspnea was subjectively scored with a visual analog scale during the last 15 s of each exercise step. Oxygen consumption measured at the dyspnea score/VO2 relationship located at the dyspnea threshold, at which dyspnea suddenly increased. Results: The maximal and submaximal values of the parameters describing the exercise and the peripheral muscular performances were: VO2 Peak: 33.8 ± 8.9 mL·min−1·kg−1; HR: 174 ± 9 b·min−1; VEmax: 65.68 ± 15.9 L·min−1; P max: 117 ± 27 W; maximal voluntary isometric force MVIF: 120.8 ± 41.9 N/m; and time to exhaustion Tlim: 53 ± 21 s. Oxygen consumption measured at the dyspnea threshold was related to VO2 Peak (R2 = 0.74; p < 0.01), Tlim (R2 = 0.78; p < 0.01), and the distance achieved during the 6MWT (R2 = 0.57; p < 0.05). Compared to the theoretical maximal values for the power output, VO2, and HR, the surgical correction did not repair the exercise performance. After the surgical correction of congenital heart disease, exercise performance was impeded by alterations of the cardiorespiratory function and peripheral local factors. A subjective evaluation of the dyspnea threshold is a reliable criterion that allows the prediction of exercise capacity in subjects suffering from congenital heart disease.

Cardiopulmonary exercise testing in interstitial lung diseases and the value of ventilatory efficiency

Interstitial lung diseases (ILDs) are diverse parenchymal pulmonary disorders, primarily characterised by alveolar and interstitial inflammation and/or fibrosis, and sharing pathophysiological similarities. Thus, patients generally harbour common respiratory symptoms, lung function abnormalities and modified exercise adaptation. The most usual and disabling complaint is exertional dyspnoea, frequently responsible for premature exercise interruption. Cardiopulmonary exercise testing (CPET) is increasingly used for the clinical assessment of patients with ILD. This is because exercise performance or dyspnoea on exertion cannot reliably be predicted by resting pulmonary function tests. CPET, therefore, provides an accurate evaluation of functional capacity on an individual basis. CPET can unmask anomalies in the integrated functions of the respiratory, cardiovascular, metabolic, peripheral muscle and neurosensory systems in ILDs. CPET uniquely provides an evaluation of all above aspects and can help clinicians shape ILD patient management. Preliminary evidence suggests that CPET may also generate valuable prognostic information in ILDs and can be used to shed light on the presence of associated pulmonary hypertension. This review aims to provide comprehensive and updated evidence concerning the clinical utility of CPET in ILD patients, with particular focus on the physiological and clinical value of ventilatory efficiency (V˙E/V˙CO2).

kTMP: A New Non-invasive Magnetic Induction Method to Modulate Cortical Excitability.

We report a novel subthreshold non-invasive brain stimulation approach that we refer to as kilohertz transcranial magnetic perturbation, or kTMP. kTMP is a magnetic induction method that delivers kHz-frequency cortical E-fields and, through amplitude modulation of the kHz carrier frequency, may mimic E-fields at physiological frequencies. To evaluate the efficacy of kTMP, we used suprathreshold TMS to elicit motor-evoked potentials (MEP) in a peripheral muscle, comparing the amplitude of the MEPs before and after kTMP stimulation. In Experiment 1, we used non-modulated kTMP with an E-field amplitude of 2 V/m over motor cortex. Ten minutes of kTMP stimulation resulted in an increase in cortical excitability in a frequency-specific manner. We replicated this effect in Experiment 2 and found that amplitude-modulation at 20 Hz produced an additional boost in cortical excitability. The only percept associated with kTMP is a faint auditory tone, making kTMP ideal for double-blind experimentation.

Beneficial Effect of Water-Based Exercise Training on Exercise Capacity in COPD Patients—a Pilot Study

Background: Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable condition, characterized by persistent airflow limitation. Exercise training is a core component of pulmonary rehabilitation in people with COPD. Water-based exercise has been studied, but it remains unclear whether water-based exercise program leads to the improvement in respiratory function, muscle strength, balance ability, and exercise capacity. We aim to study the effect of an 8-week water-based exercise program on respiratory function, muscle strength, balance ability, and exercise capacity in people with COPD.Methods: Fourteen stable COPD participants (FEV1 56.8 ± 24.6%pred) were recruited and randomized into a water-based exercise or a land-based exercise group. Both groups were trained for 8 weeks, two sessions per week. Pulmonary function, respiratory muscle strength, peripheral muscle strength, balance ability, exercise capacity [6-min walking test (6MWT), incremental shuttle walk test (ISWT), and endurance shuttle walk test (ESWT)] were assessed at baseline and at the end of the program. ANCOVA was used to conduct between-group comparisons of outcomes after adjusting for pre-intervention values.Results: Baseline characteristics of participants were not significantly different between the two groups (p ≥ 0.05). After the 8-week training program, participants in the intervention group achieved larger gains in ESWT (Δ663.4 ± 279.5 vs. Δ45.4 ± 93.2 s, p = 0.001). In addition, maximal inspiratory pressure (MIP) was significantly increased more in the intervention group (Δ11.1 ± 7.8 vs. Δ1.1 ± 5.7 cmH2O, p = 0.026). However, no significant differences in pulmonary function, peripheral muscle strength, balance ability variables, 6MWD (p = 0.248), and ISWT (p = 0.506) were observed between the two groups.Conclusions: The water-based exercise program could be recommended to the COPD rehabilitation program for improving the endurance exercise capacity and inspiratory muscle strength.Clinical Trial Registration:www.thaiclinicaltrials.org, identifier: TCTR20210125005.

Isolated Resistance Training Programs to Improve Peripheral Muscle Function in Outpatients with Chronic Obstructive Pulmonary Diseases: A Systematic Review

This systematic review aims to establish which isolated resistance training (RT) programs have been used in outpatients with chronic obstructive pulmonary disease (COPD) and their impact on all aspects of peripheral skeletal muscle function. Electronic databases were systematically searched up to June 2021. The eligibility criteria were: (1) randomized controlled trials investigating the effects of supervised and isolated RT programs in outpatients with COPD and (2) RT programs lasting 8–12 weeks, (3) including at least one outcome measure related to trainable muscle characteristics. Initially, 6576 studies were identified, whereas 15 trials met the inclusion criteria. All the included trials reported that isolated RT improved both upper and lower limbs’ maximal strength. Muscle endurance and power also increased after RT but received less attention in the analysis. Furthermore, few studies assessed the effect of RT on muscle mass and cross-sectional area, reporting only limited improvement. Isolated RT programs carried out 2–3 days a week for 8–12 weeks improved skeletal muscle function in individuals with COPD. The RT program should be specifically focused to the trainable muscle characteristic to be improved. For this reason, we further encourage the introduction of a detailed assessment of muscle function and structure during the pulmonary rehabilitation practice.

Functional respiratory capacity in the elderly after COVID-19 — a pilot study

Background: The pandemic spread of SARS-CoV-2 has led to an unprecedented outbreak of viral pneumonia. Despite the current focus of worldwide research being the characterization of post-COVID-19 sequelae, the level of functional impact that this disease causes in the elderly who have presented moderate, severe or critical manifestations is still unknown. Objective: To identify the main consequences/sequelae on functional respiratory capacity in the elderly after CoViD-19. Methodology: A cross-sectional study was carried out in the community. Functional aerobic capacity (2min step test), dyspnea perception (modified Medical Research Council Dyspnea Questionnaire), respiratory and peripheral muscle strength (maximum inspiratory and expiratory pressure, grip strength) and the Frailty Index (Clinical Fragility Scale) were assessed in 25 community-dwelling individuals aged ≥65 years, who have had a diagnosis of CoViD-19 for up to 6 months, and in an equal number of elderly people with the same characteristics without a known diagnosis of CoViD-19. Results: The elderly with a diagnosis of CoViD-19 up to 6 months presented a decrease in the values of maximum inspiratory pressure (p=0.001) and maximum expiratory pressure (p=0.015), in aerobic capacity (p<0.001) with significant presence of desaturation on exertion (p<0.001), and increased values of dyspnea perception (p=0.001) and Frailty Index (p=0.026). Conclusion: Significant changes were found in the functional respiratory capacity of elderly patients diagnosed with CoViD-19 for up to 6 months, when compared with elderly individuals without a known diagnosis of CoViD-19. It is not possible to extrapolate the results obtained to the Portuguese population, however these results may be an important indicator in the characterization of sequelae in the elderly after infection by SARS-CoV-2. Keywords: CoViD-19, elderly, functional respiratory capacity, respiratory pressures, grip strength.