Which sit-to-stand test best differentiates functional capacity in older people?

ABSTRACT: The Sit-to-Stand (STS) test provides insight into age-related functional capacity; however, there are various variants of STS, and we do not know which of these better discriminates against age-related functional capacity. Our study aimed to compare the age-related functional capacity in older people by evaluating STS power variants, using young individuals as a reference. A cross-sectional study was conducted in 102 adults (57 women) aged 60-80 and 105 adults (54 women) aged 20-30. Participants performed five times STS (5-STS), 30-seconds STS (30s-STS), and 1-minute STS (1min-STS). Z-scores were obtained for each STS variant using power (W), relative (W/kg), and allometric (W/m2) normalization methods. A mixed repeated-measures ANOVA assessed the interactions among the STS variants, normalization methods, sex, physical activity, and tobacco history. A significant interaction between STS variants, normalization methods, and sex (p=0.002) was found. The mean effect of STS variants revealed that the 1-minSTS had the lowest Z-score (p<0.05). Significant variations were observed between STS variants in all normalization methods for women (p<0.001). However, in men, only the difference between 5-STS and 1min-STS remained consistent across normalization methods (p<0.05). Our findings highlight the efficacy of 1min-STS in distinguishing age-related functional capacity over the other STS tests, especially in women.

Assessment of the Clinical and Functional Health Status of Patients with Amyotrophic Lateral Sclerosis during the COVID-19 Pandemic in Brazil Using Telemedicine.

This study aimed to monitor the clinical and functional progression of patients with amyotrophic lateral sclerosis (ALS) and adjust ventilatory support during the COVID-19 pandemic in Brazil using telemedicine. This longitudinal case series included five evaluations from January 2019 to June 2021. The first and second assessments were performed in person and consisted of pulmonary function, respiratory muscle strength, functionality (ALS Functional Rating Scale-Revised [ALSFRS-R]) and disease staging (King's College criteria). The use of non-invasive ventilation (NIV), ALSFRS-R, and disease staging were assessed in the third, fourth, and fifth assessments during the COVID-19 pandemic, using telemedicine. The rate of functional decline was calculated by the difference in the total score of ALSFRS-R between evaluations. A cutoff of 0.77 in the ALSFRS-R was used to characterize the speed of functional decline. Eleven patients (mean age of 51 years, eight males) were assessed. The total score of the ALSFRS-R (p < 0.01) and its motor domain (p < 0.01) reduced significantly during the pandemic. NIV prescription increased from 54.4% to 83.3%. Telemedicine helped with the clinical and functional follow-up of patients with ALS.

Reliability of maximal respiratory nasal pressure tests in healthy young adults.

INTRODUCTION: Sniff nasal inspiratory (SNIP) and expiratory pressure (SNEP) may complement the assessment of respiratory muscle strength. Thus, specifying their reliability is relevant to improving the clinical consistency of both tests. OBJECTIVE: To assess the reliability of SNIP and SNEP in healthy young adults. METHODS: This cross-sectional study included self-reported healthy aged 18 to 29 years. SNIP was performed using a plug to occlude one nostril, while SNEP was conducted using a facemask. Participants performed 20 SNIP and SNEP maneuvers with 30-second intervals in between. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC) assessed the reliability of SNIP and SNEP. Analyses were conducted between the highest peak pressure and the first reproducible maneuver in men and women. RESULTS: The total sample comprised 32 participants: 16 men and 16 women. The ICC, SEM, and MDC for SNIP maneuvers were 0.994 (95%CI 0.988 to 0.997), 1.820 cmH2O, and 5.043 cmH2O, respectively. For SNEP, these parameters were 0.950 (95%CI 0.897 to 0.976), 6.03 cmH2O, and 16.716 cmH2O. The SNIP and SNEP in men showed ICC of 0.992 (95%CI 0.977 to 0.997) and 0.877 (95%CI 0.648 to 0.957), SEM of 2.07 and 7.66 cmH2O, and MDC of 5.74 and 21.23 cmH2O. In women, SNIP and SNEP presented ICC of 0.992 (95%CI 0.977 to 0.997) and 0.957 (95%CI 0.878 to 0.985), SEM of 1.15 and 6.11 cmH2O, and MDC of 3.19 and 16.95 cmH2O. Also, 60% of the highest SNIPs occurred among the 11th and 20th maneuvers in men and women. In men, 55% of the highest SNEPs occurred among the 11th and 20th maneuvers; this value was 50% in women. CONCLUSION: SNIP and SNEP showed excellent reliability. The reliability of SNIP and SNEP in men was good and excellent, respectively, whereas both tests had excellent reliability in women. Also, women reached the highest peak pressure faster than men in both tests.

Physical performance testing in post-COVID-19 patients: protocol for a systematic review of psychometric measurement properties.

INTRODUCTION: COVID-19 is an infectious disease that causes severe acute respiratory syndrome. A large variety of exercise capacity tests are used for the evaluation of post-COVID-19 patients, but the psychometric properties of these exercise tests remain undetermined in this population. This study aims to critically appraise, compare and summarise the psychometric properties (validity, reliability and responsiveness) of all physical performance tests that are used to assess exercise capacity in post-COVID-19 patients. METHODS AND ANALYSIS: This systematic review protocol follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will include studies with hospitalised adult post-COVID-19 patients (aged 18 years or older and with a confirmed diagnosis of COVID-19). The research will cover randomised controlled trials (RCTs), quasi-RCTs and observational studies published in English and performed in the following settings: hospital, rehabilitation centre, outpatient clinic. We will search the following databases with no date restrictions: PubMed/MEDLINE, EMBASE, SciELO, Cochrane Library, CINAHL and Web of Science. Two authors will independently assess the risk of bias (using the Consensus-Based Standards for the Selection of Health Measurement Instruments Risk of bias checklist) and the certainty of evidence (using the Grading of Recommendations, Assessment, Development and Evaluations). According to the results obtained, data will be meta-analysed or reported narratively. ETHICS AND DISSEMINATION: No ethical approval is required for this publication since it will be based on published data. Results of this review will be disseminated via peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42021242334.

Non-invasive assessment of fatigue and recovery of inspiratory rib cage muscles during endurance test in healthy individuals.

INTRODUCTION: Fatigue is defined as loss of capacity to develop muscle force and/or velocity that is reversible at rest. We assessed non-invasively the fatigue and recovery of inspiratory rib cage muscles during two respiratory endurance tests in healthy individuals. METHODS: The sniff nasal inspiratory pressure (SNIP) was assessed before and after two respiratory endurance tests: normocapnic hyperpnea (NH) and inspiratory pressure threshold loading (IPTL). Contractile (maximum rate of pressure development and time to peak pressure) and relaxation parameters (maximum relaxation rate [MRR], time constant of pressure decay [τ], and half relaxation time) obtained from sniff curves and shortening velocity and mechanical power estimated using optoelectronic plethysmography were analyzed during SNIP maneuvers. Respiratory muscle activity (electromyography) and tissue oxygenation (near-infrared spectroscopy-NIRS) were obtained during endurance tests and SNIP maneuvers. Fatigue development of inspiratory rib cage muscles was assessed according to the slope of decay of median frequency. RESULTS: Peak pressure during SNIP decreased after both protocols (p <0.05). MRR, shortening velocity, and mechanical power decreased (p <0.05), whereas τ increased after IPTL (p <0.05). The median frequency of inspiratory rib cage muscles (i.e., sum of sternocleidomastoid, scalene, and parasternal) decreased linearly during IPTL and exponentially during NH, mainly due to the sternocleidomastoid. CONCLUSION: Fatigue development behaved differently between protocols and relaxation properties (MRR and τ), shortening velocity, and mechanical power changed only in the IPTL.

New reference values for maximum respiratory pressures in healthy Brazilian children following guidelines recommendations: A regional study.

OBJECTIVE: To determine reference values for maximum static respiratory pressures in healthy children from a Brazilian region, following recommendations of the European Respiratory Society (ERS) and the Brazilian Society of Pneumology and Tisiology (SBPT). METHODS: A cross-sectional observational study was conducted with healthy children (6 to 11 years) of both sexes. The maximum inspiratory and expiratory pressures (PImax and PEmax, respectively) were measured using a digital manometer. Each child performed a minimum of three and a maximum of five maneuvers; three acceptable and reproducible maneuvers were considered for analysis. Minimum time for each maneuver was 1.5 seconds, with a one-second plateau, and one minute of rest between them. A stepwise multiple linear regression analysis was conducted for PImax and PEmax, considering correlations between independent variables: age, weight, and sex. RESULTS: We included 121 children (62 girls [51%]). Boys reached higher values for maximum respiratory pressures than girls. Respiratory pressures increased with age showing moderate effect sizes (PImax: f = 0.36; PEmax: f = 0.30) between the stratified age groups (6-7, 8-9, and 10-11 years). Age and sex were included in the PImax equation (PImax = 24.630 + 7.044 x age (years) + 13.161 x sex; R2 = 0.189). PEmax equations were built considering age for girls and weight for boys [PEmax (girls) = 55.623 + 4.698 x age (years) and PEmax (boys) = 82.617 + 0.612 x weight (kg); R2 = 0.068]. CONCLUSIONS: This study determined new reference equations for maximal respiratory pressures in healthy Brazilian children, following ERS and SBPT recommendations.

Physical therapy for the management of motor symptoms in amyotrophic lateral sclerosis: protocol for a systematic review.

INTRODUCTION: The prescription of an intervention plan can be challenging for the physical therapist, considering clinical phenotypes, individual prognosis and the rapid, progressive and deteriorating nature of amyotrophic lateral sclerosis (ALS). In this context, therapeutic exercises (eg, resistance and aerobic exercises) for patients with ALS remain controversial and may influence the treatment plan. Therefore, this review aims to critically assess whether physical therapy interventions are effective for improving functional capacity, quality of life and fatigue of individuals with ALS. METHODS AND ANALYSIS: Studies will be selected according to eligibility criteria, and language, geographical area or publication date will not be restricted. Four databases will be used: MEDLINE, EMBASE, Cochrane Library (CENTRAL) and Physiotherapy Evidence Database (PEDro). Searches will also be conducted on ClinicalTrials.gov and references from included studies. We plan to conduct the searches between October and December 2022. Two independent authors will examine titles and abstracts and exclude irrelevant studies and duplicates. We will assess the quality of studies and quality of evidence, and disagreements will be resolved with a third researcher. The findings will be presented in the text and tables; if possible, we will perform meta-analyses. ETHICS AND DISSEMINATION: No ethical approval is required because this study does not involve human beings. We will publish our findings in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42021251350.

Psychometric properties of the sit-to-stand test for patients with pulmonary hypertension: A systematic review protocol.

BACKGROUND: Pulmonary hypertension (PH) is a complex syndrome characterized by increased pulmonary arterial pressure and classified into five groups, according to dyspnea on exertion and systemic muscle dysfunction. These symptoms can be identified using the sit-to-stand test (STS), which indirectly evaluates exercise tolerance and lower limb muscle strength. Previous studies used the STS in PH; however, psychometric properties to understand and validate this test were not described for patients with PH. OBJECTIVE: To evaluate the psychometric properties (validity, reliability, and responsiveness) of different STS protocols in patients with PH. METHODS AND ANALYSES: This is a systematic review protocol that will include studies using STS in patients with PH. Searches will be conducted on PubMed/MEDLINE, EMBASE, SciELO, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases following PICOT mnemonic strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). Rayyan software will be used for study selection. The Risk of bias will be assessed using the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) tool, while the quality of evidence will be assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Two researchers will independently conduct the study, and a third researcher will be consulted in case of disagreement. The psychometric properties will be evaluated according to the COSMIN. This protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO, no. CRD42021244271). CONCLUSION: This systematic review will attempt to identify and show the available evidence on STS for different groups of PH and report validity, reliability, and responsiveness of different protocols.

After-effects of thixotropic conditionings on operational chest wall and compartmental volumes of patients with Parkinson's disease.

Individuals with Parkinson's disease (PD) present respiratory dysfunctions, mainly due to decreased chest wall expansion, which worsens with the course of the disease. These findings contribute to the restrictive respiratory pattern and the reduction in chest wall volume. According to literature, inspiratory muscle thixotropic conditioning maneuvers may improve lung volumes in these patients. The study aimed to determine the after-effects of respiratory muscle thixotropic maneuvers on breathing patterns and chest wall volumes of PD. A crossover study was performed with twelve patients with PD (8 males; mean age 63.9±8.8 years, FVC%pred 89.7±13.9, FEV1%pred 91.2±15, FEV1/FVC%pred 83.7±5.7). Chest wall volumes were assessed using OEP during thixotropic maneuvers. Increases in EIVCW (mean of 126mL, p = 0.01) and EEVCW (mean of 150mL, p = 0.005) were observed after DITLC (deep inspiration from total lung capacity) due to increases in pulmonary (RCp) and abdominal (RCa) ribcage compartments. Changes in ICoTLC (inspiratory contraction from TLC) led to significant EIVCW (mean of 224mL, p = 0.001) and EEVCW (mean of 229mL, p = 0.02) increases that were mainly observed in the RCp. No significant changes were found when performing DERV (deep expiration from residual volume) and ICoRV (Inspiratory contraction from RV). Positive correlations were also observed between the degree of inspiratory contraction during ICoTLC and EEVRCp (rho = 0.613, p = 0.03) and EIVRCp (rho = 0.697, p = 0.01) changes. Thixotropy conditioning of inspiratory muscles at an inflated chest wall volume increases EIVCW and EEVCW in the ten subsequent breaths in PD patients. These maneuvers are easy to perform, free of equipment, low-cost, and may help patients improve chest wall volumes during rehabilitation.

Impaired functional exercise capacity and greater cardiovascular response to the 6-min walk test in congenital generalized lipodystrophy.

BACKGROUND: Congenital Generalized Lipodystrophy (CGL) is an ultra-rare disease characterized by metabolic disorders. However, the evaluation of functional exercise capacity, cardiovascular (CV) response to exercise, and peripheral arterial disease (PAD) in CGL is scarce. Here we evaluated the performance and CV response to exercise and their association with PAD in CGL compared to healthy individuals. METHODS: Twelve CGL and 12 healthy subjects matched for age and gender were included. Functional exercise capacity, CV response, and PAD were measured using the six-minute walk test (6MWT) and ankle-brachial index (ABI), respectively. RESULTS: At baseline, CGL subjects showed reduced predicted walked distance (6MWD) (p = 0.009) and increased heart rate (HR), systolic (SBP), and diastolic (DBP) pressures compared to healthy subjects (p < 0.05). Most CGL subjects presented normal ABI values (1.0 ≤ ABI ≤ 1.4). Only 25% (n = 3) had ABI ≤ 0.9. CGL subjects did not present changes in ABI and blood pressure 12 months after metreleptin (MLP) replacement, but they walked a greater 6MWD than baseline (p = 0.04). Further, 6MWD and right ABI measurements were positively correlated in CGL subjects (p = 0.03). Right ABI negatively correlated with glucose, triglycerides, and VLDL-c (p < 0.05). CONCLUSIONS: We observed that CGL subjects had lower functional exercise capacity and higher cardiovascular effort for similar performance of 6MWT, suggesting that strategies for decreasing exercise effort in this population should be essential. Furthermore, better physical performance was associated with high ABI in CGL. Additional studies are needed to clarify leptin's role in preserving functional exercise capacity in CGL.

Effects of respiratory physiotherapy in patients with amyotrophic lateral sclerosis: protocol for a systematic review of randomised controlled trials.

INTRODUCTION: Respiratory muscle weakness and ventilatory failure are common complications in patients with amyotrophic lateral sclerosis (ALS) and may lead to death. Respiratory physiotherapy may improve lung function in this population. This study aims to investigate the effects of respiratory physiotherapy on lung function, cough efficacy and functional status of patients with ALS. METHODS AND ANALYSIS: A protocol was published on the International prospective register of systematic reviews (PROSPERO). The research will cover randomised controlled trials, with no language or publication date restriction, available in the following databases: MEDLINE/PubMed, EMBASE, Cochrane Library, Web of Science and Physiotherapy Evidence Database. The research question will be answered using a search strategy adapted for each database. Searches in databases will be conducted from January 2021 to December 2022. Two authors using the Cochrane risk of bias tool for randomised trials V.2 and Grading of Recommendations, Assessment, Development and Evaluations, respectively, will assess risk of bias and quality of evidence independently. According to the results obtained, data will be reported as a meta-analysis or a narrative report. ETHICS AND DISSEMINATION: No previous ethical approval is required for this publication since data used are already published. Results of this review will be disclosed via peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42021251842.

Remote versus face-to-face home-based exercise programme in people with amyotrophic lateral sclerosis: protocol for a randomised clinical trial.

INTRODUCTION: Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease with variable and complex clinical manifestations that requires a multidisciplinary approach. However, face-to-face treatment in this population may experience barriers, such as difficulty accessing physical therapists or other professionals. As a result, strategies (eg, telerehabilitation) emerged to facilitate treatment and physical therapy monitoring. This study aims to evaluate the effects of remote versus face-to-face home-based exercise programmes on clinical outcomes and treatment adherence of people with ALS. METHODS AND ANALYSIS: This is a single-blind randomised clinical trial protocol that will include 44 people with clinical diagnosis of ALS at any clinical stage and aged between 18 and 80 years. Participants will be randomised into two groups after face-to-face evaluation and perform a home-based exercise programme three times a week for 6 months. A physical therapist will monitor the exercise programme once a week remotely (phone calls-experimental group) or face-to-face (home visits-control group). The primary outcome measure will be functional capacity (Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised). Secondary outcomes will include disease severity (Amyotrophic Lateral Sclerosis Severity Scale), fatigue (Fatigue Severity Scale), pain (Visual Analogue Scale and body pain diagram), adverse events and adherence rate. Outcomes will be initially evaluated face-to-face and revaluated remotely every 2 months and 1 month after interventions. Linear mixed models will compare outcome measures between groups and evaluations (α=5%). ETHICS AND DISSEMINATION: This study was approved by the research ethics committee of Hospital Universitário Onofre Lopes/Universidade Federal do Rio Grande do Norte (no. 3735479). We expect to identify the effects of an exercise programme developed according to ALS stages and associated with remote or face-to-face monitoring on clinical outcomes using revaluations and follow-up after interventions. TRIAL REGISTRATION NUMBER: Brazilian Registry Clinical Trials (RBR-10z9pgfv).

Breathing pattern and muscle activity using different inspiratory resistance devices in children with mouth breathing syndrome.

Aim: The aim of this study was to evaluate the acute effects of different inspiratory resistance devices and intensity of loads via nasal airway on the breathing pattern and activity of respiratory muscles in children with mouth breathing syndrome (MBS). Methods: Children with MBS were randomised into two groups based on inspiratory load intensity (20% and 40% of the maximal inspiratory pressure). These subjects were assessed during quiet breathing, breathing against inspiratory load via nasal airway and recovery. The measurements were repeated using two different devices (pressure threshold and flow resistance). Chest wall volumes and respiratory muscle activity were evaluated by optoelectronic plethysmography and surface electromyography, respectively. Results: During the application of inspiratory load, there was a significant reduction in respiratory rate (p<0.04) and an increase in inspiratory time (p<0.02), total time of respiratory cycle (p<0.02), minute ventilation (p<0.03), tidal volume (p<0.01) and scalene and sternocleidomastoid muscles activity (root mean square values, p<0.01) when compared to quiet spontaneous breathing and recovery, regardless of load level or device applied. The application of inspiratory load using the flow resistance device showed an increase in the tidal volume (p<0.02) and end-inspiratory volume (p<0.02). Conclusion: For both devices, the addition of inspiratory loads using a nasal interface had a positive effect on the breathing pattern. However, the flow resistance device was more effective in generating volume and, therefore, has advantages compared to pressure threshold.

Electrical activity and fatigue of respiratory and locomotor muscles in obstructive respiratory diseases during field walking test.

INTRODUCTION: In subjects with obstructive respiratory diseases the increased work of breathing during exercise can trigger greater recruitment and fatigue of respiratory muscles. Associated with these changes, lower limb muscle dysfunctions, further contribute to exercise limitations. We aimed to assess electrical activity and fatigue of two respiratory and one locomotor muscle during Incremental Shuttle Walking Test (ISWT) in individuals with obstructive respiratory diseases and compare with healthy. METHODS: This is a case-control study. Seventeen individuals with asthma (asthma group) and fifteen with chronic obstructive pulmonary disease (COPD group) were matched with healthy individuals (asthma and COPD control groups). Surface electromyographic (sEMG) activity of sternocleidomastoid (SCM), scalene (ESC), and rectus femoris (RF) were recorded during ISWT. sEMG activity was analyzed in time and frequency domains at baseline and during the test (33%, 66%, and 100% of ISWT total time) to obtain, respectively, signal amplitude and power spectrum density (EMG median frequency [MF], high- and low-frequency bands, and high/low [H/L] ratio). RESULTS: Asthma group walked a shorter distance than controls (p = 0.0007). sEMG amplitudes of SCM, ESC, and RF of asthma and COPD groups were higher at 33% and 66% of ISWT compared with controls groups (all p<0.05). SCM and ESC of COPD group remained higher until 100% of the test. MF of ESC and RF decreased in asthma group (p = 0.016 and p < 0.0001, respectively) versus controls, whereas MF of SCM (p < 0.0001) decreased in COPD group compared with controls. H/L ratio of RF decreased (p = 0.002) in COPD group versus controls. CONCLUSION: Reduced performance is accompanied by increased electromyographic activity of SCM and ESC and activation of RF in individuals with obstructive respiratory diseases during ISWT. These are susceptible to be more pronounced respiratory and peripheral muscle fatigue than healthy subjects during exercise.

Association between performance on the Glittre ADL-test and the functional capacity of patients with HF: A cross-sectional study.

Background: The Weber classification based on peak VO2 is a well-established method for categorizing patients with heart failure (HF) regarding severity. However, other submaximal tests such as the Glittre ADL-Test have been gaining prominence in practice due to a coherent and more comprehensive correlation with limitations for performing activities of daily living in patients with heart failure.Objective: To investigate the correlation between the time required to perform the Glittre ADL-Test and the peak VO2 in patients with HF.Methods: A cross-sectional study conducted with 40 adult individuals (21 to 65 years) diagnosed with HF of all etiologies, with LVEF<50% and NYHA II and III.Results: The average time for performing the Glittre ADL-Test was 284.9 seconds, and a significant difference was found between Weber classification classes A and C (p = .01). Significant correlations with peak VO2 were also found (r = -0.424 - p < .01). Thirty (30) patients performed a second test, and the ICC found in the reproducibility analysis was 0.75 (95% CI 0.14-0.91) and p < .01.Conclusion: The Glittre ADL-Test was able to reflect the functional performance of individuals with HF, suggesting that it represents an evaluation tool which can be safely used in clinical practice.

Weaning from mechanical ventilation in people with neuromuscular disease: a systematic review.

OBJECTIVE: This systematic review aimed in assessing the effects of different weaning protocols in people with neuromuscular disease (NMD) receiving invasive mechanical ventilation, identifying which protocol is the best and how different protocols can affect weaning outcome success, duration of weaning, intensive care unit (ICU) and hospital stay and mortality. DESIGN: Systematic review. DATA SOURCES: Electronic databases (MEDLINE, EMBASE, Web of Science and Scopus) were searched from January 2009 to August 2020. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Randomised controlled trials (RCTs) and non-RCT that evaluated patients with NMD (adults and children from 5 years old) in the weaning process managed with a protocol (pressure support ventilation; synchronised intermittent mandatory ventilation; continuous positive airway pressure; 'T' piece). PRIMARY OUTCOME: Weaning success. SECONDARY OUTCOMES: Weaning duration, ICU stay, hospital stay, ICU mortality, complications (pneumothorax, ventilation-associated pneumonia). DATA EXTRACTION AND SYNTHESIS: Two review authors assessed the titles and the abstracts for inclusion and reviewed the full texts independently. RESULTS: We found no studies that fulfilled the inclusion criteria. CONCLUSIONS: The absence of studies about different weaning protocols for patients with NMD does not allow concluding the superiority of any specific weaning protocol for patients with NMD or determining the impact of different types of protocols on other outcomes. The result of this review encourages further studies. PROSPERO REGISTRATION NUMBER: CRD42019117393.

Effects of diaphragmatic control on multiparametric analysis of the sniff nasal inspiratory pressure test and inspiratory muscle activity in healthy subjects.

BACKGROUND: We investigated the influence of diaphragmatic activation control (diaphC) on the relaxation rate, contractile properties and electrical activity of the inspiratory muscles of healthy subjects. Assessments were performed non-invasively using the sniff inspiratory pressure test (SNIP) and surface electromyography, respectively. METHODS: Twenty-two subjects (10 men and 12 women) performed 10 sniff maneuvers in two different days: with and without diaphC instructions. For the SNIP test with diaphC, the subjects were instructed to perform intense activation of the diaphragm. The tests with the best SNIP values were used for analysis. RESULTS: The maneuver with diaphC when compared to the maneuver without diaphC exhibited significant lower values for: SNIP (p <0.01), maximum relaxation rate (MRR) (p <0.01), maximum rate of pressure development (MRPD) (p <0.01), contraction times (CT) (p = 0.02) and electrical activity of the sternocleidomastoid (SCM) (p <0.01), scalene (SCL) (p = 0.01) and intercostal (CI) (p = 0.03) muscles. In addition, the decay constant (tau, τ) and relaxation time (½ RT) did not present any changes. CONCLUSION: The diaphragmatic control performed during the SNIP test influences the inspiratory pressure and the contractile properties of inspiratory muscles. This occurs due to changes in the pattern of muscle recruitment, which change force velocity characteristics of the test. Thus, instruction on diaphC should be encouraged for better performance of the SNIP test and for evaluation targeting the diaphragm muscle activity.

Changes in electromyographic activity, mechanical power, and relaxation rates following inspiratory ribcage muscle fatigue.

Muscle fatigue is a complex phenomenon enclosing various mechanisms. Despite technological advances, these mechanisms are still not fully understood in vivo. Here, simultaneous measurements of pressure, volume, and ribcage inspiratory muscle activity were performed non-invasively during fatigue (inspiratory threshold valve set at 70% of maximal inspiratory pressure) and recovery to verify if inspiratory ribcage muscle fatigue (1) leads to slowing of contraction and relaxation properties of ribcage muscles and (2) alters median frequency and high-to-low frequency ratio (H/L). During the fatigue protocol, sternocleidomastoid showed the fastest decrease in median frequency and slowest decrease in H/L. Fatigue was also characterized by a reduction in the relative power of the high-frequency and increase of the low-frequency. During recovery, changes in mechanical power were due to changes in shortening velocity with long-lasting reduction in pressure generation, and slowing of relaxation [i.e., tau (τ), half-relaxation time (½RT), and maximum relaxation rate (MRR)] was observed with no significant changes in contractile properties. Recovery of median frequency was faster than H/L, and relaxation rates correlated with shortening velocity and mechanical power of inspiratory ribcage muscles; however, with different time courses. Time constant of the inspiratory ribcage muscles during fatigue and recovery is not uniform (i.e., different inspiratory muscles may have different underlying mechanisms of fatigue), and MRR, ½RT, and τ are not only useful predictors of inspiratory ribcage muscle recovery but may also share common underlying mechanisms with shortening velocity.

Reliability of SNIP test and optimal number of maneuvers in 6-11 years healthy children.

BACKGROUND AND PURPOSE: Sniff nasal inspiratory pressure (SNIP) is a voluntary inspiratory maneuver measured through a plug occluding one nostril. The investigation of the number of maneuvers necessary to reach the highest peak of SNIP in pediatric populations has been inconsistent. Thus, this study aimed to assess the reliability of SNIP in healthy children aged 6 to 11 years according to sex and age group, and to determine the optimal number of SNIP maneuvers for this age group. METHODS: This cross-sectional study included healthy children with normal pulmonary function. We performed 12 to 20 SNIP maneuvers, with a 30 s rest between each maneuver. The reliability was tested using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC), and Bland-Altman analysis for agreement. RESULTS: A total of 121 healthy children (62 girls [51%]) were included in this study. The ICC and corresponding confidence interval (CI) between the highest measure and the first reproducible maneuver were 0.752 (0.656-0.824), SEM = 10.37 cmH2O, and MDC = 28.74 cmH2O. For children aged 6 to 7 years, the ICC was 0.669 (0.427-0.822), SEM = 10.76 cmH2O and MDC = 29.82 cmH2O; for children aged 8 to 11 years, the ICC was 0.774 (0.662-0.852), SEM = 9.74 cmH2O, and MDC = 26.05 cmH2O. For girls, the ICC was 0.817 (0.706-0.889), SEM = 9.40 cmH2O and MDC = 26.05 cmH2O; for boys, the ICC was 0.671 (0.487-0.798), SEM = 11.51 cmH2O, and MDC = 31.90 cmH2O. Approximately 80% of the total sample reached the highest SNIP before the 10th maneuver. CONCLUSIONS: SNIP demonstrated moderate reliability between the maneuvers in children aged 6 to 11 years; older children and girls reached the SNIP peak faster. Finally, results indicated that 12 maneuvers were sufficient for healthy children aged 6 to 11 years to achieve the highest SNIP peak.

Thoracoabdominal asynchrony and paradoxical motion in Duchenne muscular dystrophy and healthy subjects during cough: A case control study.

OBJECTIVE: To assess thoracoabdominal asynchrony (TAA) and inspiratory paradoxical motion at different positionings in subjects with Duchenne muscular dystrophy (DMD) versus healthy subjects during quiet spontaneous breathing (QB) and cough. METHODS: This is a case control study with a matched-pair design. We assessed 14 DMD subjects and 12 controls using optoelectronic plethysmography (OEP) during QB and spontaneous cough in 3 positions: supine, supine with headrest raised at 45°, and sitting with back support at 80°. The TAA was assessed using phase angle (θ) between upper (RCp) and lower rib cage (RCa) and abdomen (AB), as well as the percentage of inspiratory time the RCp (IPRCp ), RCa (IPRCa ), and AB (IPAB ) moved in opposite directions. RESULTS: During cough, DMD group showed higher RCp and RCa θ (p < .05), RCp and AB θ (p < .05) in supine and 45° positions, and higher RCp and Rca θ (p = .006) only in supine position compared with controls. Regarding the intragroup analysis, during cough, DMD group presented higher RCp and AB θ (p = .02) and RCa and AB θ (p = .002) in supine and higher RCa and AB θ (p = .002) in 45° position when compared to 80°. Receiver operating characteristic curve analyzes were able to discriminate TAA between controls and DMD in RCa supine position (area under the curve: 0.81, sensibility: 78.6% and specificity: 91.7%, p = .001). CONCLUSION: Subjects with DMD yields TAA with insufficient deflation of chest wall compartments and rib cage distortion during cough, by noninvasive assessment.