Respiratory Muscle Strength Is Related to Handgrip Performance in Community-Dwelling Persons Aged 80+ from the BUTTERFLY Study.

INTRODUCTION: This study aimed to evaluate the association of respiratory muscle strength with sarcopenia and its indicators in the oldest old. METHODS: Maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), and sarcopenia-related factors (handgrip strength and appendicular lean mass) were evaluated in a cohort of n = 286 (45.5% female) non-frail, community-dwelling persons aged 83.6 ± 3.0 years (age range 80-97 years). RESULTS: The sample presented a sarcopenia prevalence of 32.2%. Sarcopenic subjects showed comparable MIP and MEP as non-sarcopenic ones (female: MIP 43.9 ± 18.9 vs. 50.3 ± 19.5, p = 0.053; MEP 63.0 ± 23.0 vs. 69.2 ± 19.1, p = 0.067; male: MIP, 65.1 ± 24.4 vs. 64.4 ± 23.9, p = 0.433; MEP 87.7 ± 33.3 vs. 93.8 ± 30.9, p = 0.124). Statistically significant but very low associations were found between grip strength and MIP (r = 0.193 for male, p < 0.05 and r = 0.257 for female participants, p < 0.01) and MEP (r = 0.200 for male, p < 0.01 and r = 0.191 for female participants, p < 0.05). Lean mass was significantly correlated to MIP and MEP in female (r = 0.253, p < 0.01 and r = 0.343, p < 0.01, respectively), whereas this association was not found in male participants. Grip strength was the only statistically significant predictor of MEP (r2 = 0.212, p < 0.001), while MIP was independently predicted by age, male sex, and grip strength (r2 = 0.177, p < 0.001). CONCLUSIONS: Peripheral muscle strength is a statistically significant, albeit weak predictor for respiratory muscle strength in well-functioning, community-dwelling persons aged 80+. When confronted to a low grip strength, one should be aware of concomitant respiratory muscle weakness, as this is a known risk factor for atelectasis and pneumonia. Given the relatively low association with handgrip strength, respiratory muscle strength testing might be indicated.

Inspiratory Muscle Dysfunction Mediates and Predicts a Disease Continuum of Hypercapnic Failure in Chronic Obstructive Pulmonary Disease.

INTRODUCTION: Advanced chronic obstructive pulmonary disease (COPD) is associated with chronic hypercapnic failure. The present work aimed to comprehensively investigate inspiratory muscle function as a potential key determinant of hypercapnic respiratory failure in patients with COPD. METHODS: Prospective patient recruitment encompassed 61 stable subjects with COPD across different stages of respiratory failure, ranging from normocapnia to isolated nighttime hypercapnia and daytime hypercapnia. Arterialized blood gas analyses and overnight transcutaneous capnometry were used for patient stratification. Assessment of respiratory muscle function encompassed body plethysmography, maximum inspiratory pressure (MIP), diaphragm ultrasound, and transdiaphragmatic pressure recordings following cervical magnetic stimulation of the phrenic nerves (twPdi) and a maximum sniff manoeuvre (Sniff Pdi). RESULTS: Twenty patients showed no hypercapnia, 10 had isolated nocturnal hypercapnia, and 31 had daytime hypercapnia. Body plethysmography clearly distinguished patients with and without hypercapnia but did not discriminate patients with isolated nocturnal hypercapnia from those with daytime hypercapnia. In contrast to ultrasound parameters and transdiaphragmatic pressures, only MIP reflected the extent of hypercapnia across all three stages. MIP values below -48 cmH2O predicted nocturnal hypercapnia (area under the curve = 0.733, p = 0.052). CONCLUSION: In COPD, inspiratory muscle dysfunction contributes to progressive hypercapnic failure. In contrast to invasive tests of diaphragm strength only MIP fully reflects the pathophysiological continuum of hypercapnic failure and predicts isolated nocturnal hypercapnia.

Low-Medium and High-Intensity Inspiratory Muscle Training in Critically Ill Patients: A Systematic Review and Meta-Analysis.

Background and objectives: Mechanical ventilation is often used in intensive care units to assist patients' breathing. This often leads to respiratory muscle weakness and diaphragmatic dysfunction, causing weaning difficulties. Inspiratory muscle training (IMT) has been found to be beneficial in increasing inspiratory muscle strength and facilitating weaning. Over the years, different protocols and devices have been used. Materials and Methods: The aim of this systematic review and meta-analysis was to investigate the effectiveness of low-medium (LM-IMT) and high-intensity (H-IMT) threshold inspiratory muscle training in critically ill patients. A systematic literature search was performed for randomized controlled trials (RCTs) in the electronic databases Google Scholar, PubMed, Scopus, and Science Direct. The search involved screening for studies examining the effectiveness of two different intensities of threshold IMT in critically ill patients published the last 10 years. The Physiotherapy Evidence Database (PEDro) scale was chosen as the tool to assess the quality of studies. A meta-analysis was performed where possible. Results: Fourteen studies were included in the systematic review, with five of them having high methodological quality. Conclusions: When examining LM-IMT and H-IMT though, neither was able to reach statistically significant improvement in their maximal inspiratory pressure (MIP), while LM-IMT reached it in terms of weaning duration. Additionally, no statistical difference was noticed in the duration of mechanical ventilation. The application of IMT is recommended to ICU patients in order to prevent diaphragmatic dysfunction and facilitate weaning from mechanical ventilation. Therefore, further research as well as additional RCTs regarding different protocols are needed to enhance its effectiveness.

Inspiratory Muscle Training and Physical Fitness in Children With Down Syndrome: A Randomized Controlled Trial.

OBJECTIVE: To investigate the effect of inspiratory muscle training (IMT) on physical fitness in children with Down syndrome (DS). DESIGN: Randomized control trial. SETTING: The study was conducted in a private physical therapy center. PARTICIPANTS: Forty boys and girls with DS aged between 7 and 10 years were enrolled in this study (N=40). They were randomly and equally divided into 2 groups (A and B). INTERVENTIONS: All participants received 30 minutes of aerobic exercise training 3 times per week for 12 weeks, whereas group B received an additional 30 minutes of IMT before each aerobic exercise session. MAIN OUTCOMES MEASURES: Maximal inspiratory pressure (MIP); maximal expiratory pressure (MEP); submaximal aerobic endurance; muscular strength; endurance. RESULTS: Among the group undergoing IMT, there were significant improvements in MIP, MEP, and submaximal aerobic endurance using the six-minute walk test (6MWT); strength and endurance using the curl-up, dumbbell press, trunk lift, standing long jump, seated push-up, pull-up, and flexed-arm hang; and back saver sit and reach tests (P > 0.05). CONCLUSIONS: Inspiratory muscle training and aerobic exercise training demonstrated more significant improvements in physical fitness than in those children who received only aerobic exercise training.

Immediate effects of stretching on trunk functions using a stretch pole half-cut.

[Purpose] To analyze the immediate effects of stretching on respiratory and trunk functions using a stretch pole half-cut in healthy male participants. [Participants and Methods] Thirty healthy male participants with a mean age of 21.1 ± 0.8 years were recruited in this study. The participant had to lay on his back on the convex surface of the pole with the semicircle of the pole touching the surface of the platform mat. The convex of the pole was placed at the level from seventh to 10th thoracic vertebra for 4 min and was applied perpendicular (anatomically horizontal) to the body axis. Respiratory function and muscle strength using a spirometer with attached units, maximum-minimum chest wall expansion difference using a tape measure, and body alignment, such as angles obtained from the spinal mouse, were measured before and immediately after the intervention in random order. [Results] The total inclination angle was found to decrease significantly, while the thoracic kyphosis angle and maximum inspiratory pressure showed a significant increase. [Conclusion] This intervention was suggested to be easy for incorporating into day life and useful in situations where the subjects want to increase the maximum inspiratory pressure, such as in sports.

Diaphragmatic muscle thickness and diaphragmatic function are reduced in patients with systemic lupus erythematosus compared to those with primary Sjögren's syndrome.

INTRODUCTION: Systemic lupus erythematosus (SLE) is associated with an increased risk of pulmonary infections, as well as a rare condition known as shrinking lung syndrome (SLS). The diaphragm has an important role to play in lung physiology and might also play a role in these adverse events. Here, we aimed to investigate whether SLE patients have impairment in their diaphragmatic muscle thickness and function with respect to another connective-tissue disease: primary Sjögren's syndrome (pSS). METHOD: Patients diagnosed with SLE who were in remission or who had minimal disease activity and had at least one year of follow-up were included in this study. Patients with known lung pathology and smokers were excluded. Patients with pSS constituted the second experimental group. Ultrasonographic evaluation of the diaphragmatic muscle was conducted by an experienced independent sonographer at three time points, diaphragmatic thickness during deep and quiet inspiration and maximum expiration being measured. Diaphragmatic muscle function was evaluated with maximum expiratory pressure (MEP) and maximum inspiratory pressure (MIP). RESULTS: A total of 115 patients were studied (n = 39 SLE; n = 76 pSS). The mean ± standard deviation (SD) thickness of the diaphragmatic muscles during quiet inspiration was significantly reduced in patients with SLE compared to patients with pSS (2.32 mm vs. 2.81 mm; p < 0.05). Similarly, the thickness during deep inspiration and at maximum deep expiration were significantly lower in SLE patients (2.88 mm vs. 3.29 mm and 1.92 mm vs. 2.33 mm, respectively; p < 0.01). MIPs and MEPs, defined as the percentages of expected values, were significantly lower in patients with SLE compared to those with pSS (80% vs. 92% and 76% vs. 120%, respectively; p < 0.05). Diaphragmatic muscle thickness during deep inspiration demonstrated a moderate correlation with MIP (r = 0.434; p = 0.001). CONCLUSION: SLE patients had reduced diaphragmatic muscle thickness compared to those with pSS, which was associated with impaired functional tests. Further prospective studies are needed to investigate whether structural and functional impairments in diaphragmatic muscle play a role in an increased risk of pulmonary infections and SLS in patients with SLE.

[The predictive value of ultrasonic measurement of the diaphragmatic thickening fraction combined with the maximal inspiratory pressure in mechanical ventilation patients].

Objective: To evaluate the value of the diaphragmatic thickening fraction (DTF) combined with the maximum inspiratory pressure (MIP) for the prediction of weaning success in mechanically ventilated patients. Methods: Patients admitted to the intensive care unit (ICU) of Yijishan Hospital of Wannan Medical College and on mechanical ventilation for 24 hours from June 2018 to April 2019 were selected as the study subjects. A low-level pressure support ventilation (PSV) method was applied to conduct a spontaneous breathing test (SBT) for 30 minutes after the patients met the screening conditions for clinical weaning; and the patients were weaned when they met the clinical weaning criteria. Before weaning, the patient's MIP was measured. The right hemidiaphragmatic excursion (DE) and the thickness of the diaphragm at the end of inspiration and at the end of exhalation were measured by ultrasound, and the DTF was calculated. The statistical relationship between the DTF, DE and MIP was analyzed. The predictive value for the success of weaning was calculated with the DTF, DE and MIP and was evaluated by the area under the receiver operating characteristic curve (AUC). Results: A total of 73 patients were included in this study, including 57 patients who were successfully weaned, and 16 patients who experienced failure. The DTF of the successful weaning group (35%, 8%) was significantly higher than that of the failed weaning group (25%±5%), and the difference was statistically significant (t=6.401, P<0.01). The MIP (34±9 cmH(2)O) in the successful weaning group was significantly higher than that in the failed weaning group (23±3 cmH(2)O), and the difference was statistically significant (t=7.186, P<0.01). The ROCs for the DTF, MIP, and diaphragmatic displacement were 0.907, 0.896, and 0.749, respectively. A DTF ≥ 27.78%, with a sensitivity of 92.98%, a specificity of 81.25%, and an AUC of 0.907 (95% CI: 0.816-0.963), was used as the standard to predict the success of weaning. An MIP>26.5 cmH(2)O, with a sensitivity of 80.7%, a specificity of 93.75%, and an AUC of 0.896 (95% CI: 0.803-0.955), was used as the standard to predict the success of weaning. The AUC of DTF ≥ 27.78% and MIP ≥ 26.5 cmH(2)O was 0.920 (95% CI:0.832-0.971), and the specificity increased to 87.7%, but the sensitivity was slightly reduced to 87.5%. Conclusions: The DTF and MIP play a crucial role in determining the appropriate time and predicting the outcome of weaning of mechanical ventilation patients. Compared with the DTF and MIP alone, the DTF combined with MIP greatly improved the accuracy of predicting successful weaning.

Respiratory muscle training (RMT) in late-onset Pompe disease (LOPD): A protocol for a sham-controlled clinical trial.

INTRODUCTION: Morbidity and mortality in adults with late-onset Pompe disease (LOPD) results primarily from persistent progressive respiratory muscle weakness despite treatment with enzyme replacement therapy (ERT). To address this need, we have developed a 12-week respiratory muscle training (RMT) program that provides calibrated, individualized, and progressive pressure-threshold resistance against inspiration and expiration. Our previous results suggest that our RMT regimen is safe, well-tolerated, and results in large increases in respiratory muscle strength. We now conduct an exploratory double-blind, randomized control trial (RCT) to determine: 1) utility and feasibility of sham-RMT as a control condition, 2) the clinically meaningful outcome measures for inclusion in a future efficacy trial. This manuscript provides comprehensive information regarding the design and methods used in our trial and will aid in the reporting and interpretation of our future findings. METHODS: Twenty-eight adults with LOPD will be randomized (1:1) in blocks of 4 to RMT (treatment) or sham-RMT (control). Assessments will be conducted at pretest, posttest, 3-months detraining, and 6-months detraining. The primary outcome is maximum inspiratory pressure (MIP). Secondary outcomes include maximum expiratory pressure (MEP), 6-min walk test (6MWT), Gait, Stairs, Gowers, and Chair test (GSGC), peak cough flow (PCF), and patient-reported life activity/social participation (Rasch-built Pompe-specific Activity scale [R-Pact]). Exploratory outcomes include quantitative measures from polysomnography; patient reported measures of fatigue, daytime sleepiness, and sleep quality; and ultrasound measures of diaphragm thickness. This research will use a novel tool to provide automated data collection and user feedback, and improve control over dose. ETHICS AND DISSEMINATION: The results of this clinical trial will be promptly analyzed and submitted for publication. Results will also be made available on clinicaltrials.gov. ClinicalTrials.gov: NCT02801539, R21AR069880.

Intra- and inter-rater reliability of maximum inspiratory pressure measured using a portable capsule-sensing pressure gauge device in healthy adults.

BACKGROUND: Measurement of maximum inspiratory pressure is the most prevalent method used in clinical practice to assess the strength of the inspiratory muscles. Although there are many devices available for the assessment of inspiratory muscle strength, there is a dearth of literature describing the reliability of devices that can be used in clinical patient assessment. The capsule-sensing pressure gauge (CSPG-V) is a new tool that measures the strength of inspiratory muscles; it is easy to use, noninvasive, inexpensive and lightweight. OBJECTIVE: To test the intra- and inter-rater reliability of a CSPG-V device in healthy adults. METHODS: A cross-sectional study involving 80 adult subjects with a mean (± SD) age of 22±3 years was performed. Using simple randomization, 40 individuals (20 male, 20 female) were used for intrarater and 40 (20 male, 20 female) were used for inter-rater reliability testing of the CSPG-V device. The subjects performed three inspiratory efforts, which were sustained for at least 3 s; the best of the three readings was used for intra- and inter-rater comparison. The intra- and inter-rater reliability were calculated using intraclass correlation coefficients (ICCs). RESULTS: The intrarater reliability ICC was 0.962 and the inter-rater reliability ICC was 0.922. CONCLUSION: Results of the present study suggest that maximum inspiratory pressure measured using a CSPG-V device has excellent intraand inter-rater reliability, and can be used as a diagnostic and prognostic tool in patients with respiratory muscle impairment.

HISTORIQUE: La mesure de la pression inspiratoire maximale est la méthode la plus utilisée en pratique clinique pour évaluer la force des muscles inspiratoires. Même si de nombreux dispositifs sont conçus pour effectuer cette mesure, très peu de publications décrivent la fiabilité de ceux qui peuvent être utilisés pour l'évaluation clinique des patients. Les capsules manométriques (CM-V), un nouvel outil, mesurent la force des muscles inspiratoires. Ils sont faciles à utiliser, non invasifs, peu coûteux et légers. OBJECTIF: Vérifier la fiabilité intraévaluateurs et interévaluateurs d'un CM-V chez des adultes en santé. MÉTHODOLOGIE: Des chercheurs ont réalisé une étude transversale par randomisation simple auprès de 40 adultes (20 hommes, 20 femmes) pour les tests de fiabilité intraévaluateurs et de 40 adultes (20 hommes, 20 femmes) d'un âge moyen (± ÉT) de 22±3 ans pour les tests de fiabilités interévaluateurs. Les sujets ont effectué trois efforts inspiratoires soutenus pendant au moins trois secondes. La meilleure des trois lectures servait à la comparaison intraévaluateurs et interévaluateurs. La fiabilité intraévaluateurs et interévaluateurs a été calculée au moyen de coefficients de corrélation intraclasse (CCI). RÉSULTATS: Le CCI de fiabilité intraévaluateurs était de 0,962 et le CCI de fiabilité interévaluateurs, de 0,922. CONCLUSION: D'après les résultats de la présente étude, la pression inspiratoire maximale mesurée au moyen de la CM-V a une excellente fiabilité intraévaluateurs et interévaluateurs et peut être utilisée comme outil diagnostique et pronostique chez les patients ayant un déficit des muscles respiratoires.

Effect of inspiratory muscle training in children with asthma: a systematic review and meta-analysis of randomized controlled trials.

Background: Asthma is a common chronic respiratory disease in children. Alongside pharmacological interventions, inspiratory muscle training (IMT) emerges as a complementary therapeutic approach for asthma management. However, the extent of its efficacy in pediatric populations remains uncertain when compared to its benefits in adults. This systematic review aims to evaluate the effectiveness of IMT with threshold loading in children with asthma. Methods: Randomized controlled trials (RCTs) evaluating the efficacy of inspiratory muscle training in pediatric asthma patients were identified through June 2023 across various literature databases, including PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAL), Web of Science, China Knowledge Resource Integrated Database (CNKI), Wei Pu Database, Wan Fang Database, and Chinese Biomedical Database (CBM). These trials compared inspiratory muscle training against sham inspiratory muscle training and conventional care. Eligible studies were assessed in terms of risk of bias and quality of evidence. Where feasible, data were pooled and subjected to meta-analysis, with results reported as mean differences (MDs) and 95% confidence intervals (CIs). Results: Six trials involving 333 patients were included in the analysis. IMT demonstrated significant improvements in maximum inspiratory pressure (MIP) (MD 25.36, 95% CI 2.47-48.26, P = 0.03), maximum expiratory pressure (MEP) (MD 14.72, 95% CI 4.21-25.24, P = 0.006), forced vital capacity in percent predicted values [FVC(% pred)] (MD 3.90, 95% CI 1.86-5.93, P = 0.0002), forced expiratory volume in the first second in percent predicted values [FEV1(% pred)] (MD 4.96, 95% CI 2.60-7.32, P < 0.0001), ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC) (MD 4.94, 95% CI 2.66-7.21, P < 0.0001), and asthma control test (ACT) (MD = 1.86, 95% CI: 0.96-2.75, P < 0.0001). Conclusions: Findings from randomized controlled trials indicate that inspiratory muscle training enhances respiratory muscle strength and pulmonary function in pediatric asthma patients. Systematic Review Registration: www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023449918, identifier: CRD42023449918.

Maximum abdominal excursion assessment using an abdominal excursion measuring device: Reliability and validity of a new device for simple and quantitative assessment of respiratory function.

This study aimed to verify the reliability and validity of abdominal expansion and respiratory function measurements. Forty healthy adult males underwent lung capacity, effort lung capacity, respiratory muscle strength, cough strength, diaphragm ultrasound, and abdominal expansion measurements. Abdominal expansion was measured using a device developed to accurately evaluate abdominal movements and calculate maximum abdominal expansion on the ventral side (AE-max: the difference between maximal abdominal contraction at the same time as maximal-effort expiration and maximal abdominal expansion at the same time as maximal-effort inspiration). Intra- and inter-rater reliabilities of the AE-max measurements were examined, the paired t-test was used for assessing the ratios of the expansion and contraction displacement components in AE-max, and regression analysis was used to obtain equations for predicting maximum inspiratory pressure (MIP) based on AE-max. Both intra- and inter-rater reliabilities were high. Criterion-related validity showed that AE-max was associated with all respiratory function parameters, especially MIP, and a high percentage of expansion displacement. Regression analysis showed that AE-max was significantly associated with MIP. Based on its association with MIP, the large proportion of expansion displacement in AE-max, and the results of the multiple regression analysis, we conclude that AE-max is a helpful measure for estimating MIP.

A Secondary Analysis of Short- and Long-Term Variability of Inspiratory Muscle Performance in People Living With SCI.

Objectives: To explore the expected variability in repeated short-term (ST) and long-term (LT) inspiratory muscle performance (IMP) in individuals with chronic spinal cord injury (SCI). Methods: Maximal inspiratory pressure (MIP), sustained MIP (SMIP), and inspiratory duration (ID) were collected from 22 individuals with chronic SCI (C1-T9, American Spinal Injury Association Impairment Scale [AIS] A-C) over 18 months. ST data were collected four times within 2 weeks (n = 19). LT data were collected at two time points at least 7 months apart (n = 20). Results: SMIP was the most reliable IMP assessment with an intraclass correlation coefficient (ICC) of 0.959, followed by MIP (ICC 0.874) and ID (ICC 0.689). The ID was the only ST measure to have a significant difference [MIP: F(3, 54) = 2.5, p = .07; SMIP: F(3, 54) = 1.3, p = .29; ID: F(1.4, 25.6) = 4.8, p = .03]. Post hoc analysis showed the mean day 1 ST ID measure was significantly different from both days 3 and 4. The percent change of ID from day 3 to day 6 was 11.6%. No LT measures differed significantly [mean change (SD) [95% CI] for MIP: 5.2 cm H2O (18.8) [-3.6, 13.9], p = .235; SMIP: 60.9 pressure time unit (166.1) [-16.9, 138.6], p = .118; ID: 0.1 s (2.5) [-1.1, 1.3], p = .855]. Conclusion: These data provide a foundation for understanding normal variance in ST and LT IMP in the SCI population. Change in MIP function outside 10% is likely a true and meaningful change and may help clinicians recognize individuals with SCI at risk for respiratory compromise. Future studies should explore changes in MIP and SMIP that are associated with meaningful functional changes.

The relationship between inspiratory muscle strength, venous refilling time, disease severity, and functional capacity in patients with chronic venous insufficiency.

BACKGROUND: Our aim is to evaluate the relationship between inspiratory muscle strength and venous refilling time, disease severity, and functional capacity in patients with chronic venous insufficiency (CVI). METHODS: Sixty-one patients (49 female, aged 20-65 ) were enrolled in the study. The demographic characteristics of the patients were questioned. All patients were assessed with maximum inspiratory and expiratory pressure (MIP/MEP) for inspiratory and expiratory muscle strength, photoplethysmography for venous refilling time (VRT), venous clinical severity score (VCSS) for disease severity, and 6-min walk test (6-MWT) for functional capacity. RESULTS: The mean age of the patients was 49.48 ± 13.19 years, and the mean duration of disease was 9.18 ± 6.57 years. There was statistically significant positive association between MIP and VRT(r: 0.331, p: 0.009), 6-MWT (r: 0.616, p < 0.001) values, and there was negative association between MIP and VCSS(r: -0.439 p < 0.001) scores. CONCLUSION: Evaluation of inspiratory muscle strength and elimination of its deficiency, providing interventions to approach normative values have the potential to contribute positively to the treatment of the patient.

Validation of the Single Breath Count Test for Assessment of Inspiratory Muscle Strength in Healthy Subjects and People with Neuromuscular Disorders.

OBJECTIVE: This study aimed to validate the single breath count test (SBCT) against volitional measures of respiratory muscle function in healthy subjects and people with neuromuscular disorders (NMD; n = 100 per group). METHODS: Testing comprised upright and supine SBCT, forced vital capacity (FVC), maximum inspiratory pressure (MIP), and sniff nasal inspiratory pressure (SNIP). Predictability of FVC by SBCT was assessed using logarithmic regression analysis. Receiver operating characteristics curves were used to identify SBCT thresholds for lung restriction (FVC < 80% predicted), inspiratory muscle weakness (MIP < 60 cmH2O), and indication for non-invasive ventilation (NIV) in NMD patients. RESULTS: In both groups, SBCT showed moderate correlation with FVC. In patients, SBCT values were also correlated with MIP and SNIP. Strength of correlations was similar with supine and upright SBCT which accounted for 23.7% of FVC variance in healthy individuals (44.5% in patients). Predictive thresholds of upright SBCT were < 27 for MIP < 60 cmH2O (sensitivity 0.61/specificity 0.86), <39 for NIV indication (0.92/0.46), and <41 for FVC < 80% predicted (0.89/0.62). CONCLUSION: The SBCT is positively correlated with spirometry. It predicts both lung restriction and NIV indication in NMD patients. The SBCT allows for remote monitoring and may substitute for spirometry/manometry if appropriate devices are unavailable.

Respiratory Muscle Function in Older Adults with Chronic Respiratory Diseases after Pulmonary Rehabilitation in Subterranean Salt Chambers.

Training the respiratory muscles is a crucial aspect of pulmonary rehabilitation. The purpose of this study was to assess the function of respiratory muscles in older adults both before and after a period of pulmonary rehabilitation and treatment stay within the underground chambers of a salt mine. A total of 50 patients aged 65 years and older with chronic respiratory conditions was enrolled in the study. These participants underwent a 3-week subterranean pulmonary rehabilitation (PR) program in the "Wieliczka" Salt Mine. Levels of sniff nasal inspiratory pressure (SNIP), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP) were measured using the MicroRPM both before and after the outpatient PR program conducted 135 m underground. A total of 44 patients with a mean age of 68.8 ± 2.9 years who completed the PR program and tests were included in the analysis. The average changes in the parameters of pulmonary function before and after the PR were: MIP 8.8 cmH2O, MEP 7.1 cmH2O, and SNIP 11.2 cmH2O (for p < 0.05). For patients older than 70 years, beneficial changes were only observed for MEP, which increased by 9.3 cmH2O (for p < 0.05). Speleotherapy combined with pulmonary rehabilitation improves respiratory muscle function in older adults with chronic respiratory diseases, mainly in terms of MEP. Therefore, a greater emphasis on inspiratory muscle training in the rehabilitation program should be considered.

Decreased phrenic nerve compound muscle action potential, inspiratory muscle strength, and exercise capacity after COVID-19.

Objectives: Respiratory muscle weakness with higher ventilatory demands were reported even in patients recovering from only mild COVID-19 symptoms. Aim of this study was to assess the function of phrenic nerve and inspiratory respiratory muscle as well as cardiopulmonary exercise capacity in patients with prolonged exertional dyspnea after COVID-19 infection. Methods: In this observational exploratory study, electrophysiological examination of the phrenic nerve, inspiratory muscle capacity as well as lung function test, 6-min walk distance (6MWD) and cardiopulmonary exercise test, have been performed in 22 patients post COVID-19 diagnosis (post-CoV). Results: Exercise capacity (peak workload, Wpeak % predicted and peak oxygen uptake, VO2peak % predicted) were significantly affected in the post-CoV patients (61.8 ± 23.3 Wpeak % and 70.9 ± 22.3 VO2peak %). Maximum inspiratory pressure (MIP) was reduced (60.1 ± 25.5 mbar). In 6 of the 22 patients the electrophysiological response of the phrenic nerve was pathologically decreased (reduced compound muscle action potential, CMAP), while nerve conduction velocity (NCV) was normal, which corresponds to reduced muscle fiber contraction capacity. Positive relationships were demonstrated between 6MWD and MIP (rs = 0.88) as well as quality of life questionnaire (CRQ) and MIP (rs = 0.71) only in patients with reduced CMAP. Discussion: Respiratory muscle weakness and exercise capacity is associated with reduced phrenic nerve CMAP without signs of neuropathy. This indicates that muscle fiber pathology of the diaphragm may be one pathophysiological factor for the prolonged respiratory symptoms after COVID-19 infections.

A meta-analysis of post-exercise outcomes in people with amyotrophic lateral sclerosis.

Objective: To systematically evaluate post-exercise outcomes related to function and quality of life in people with ALS. Methods: PRISMA guidelines were used for identifying and extracting articles. Levels of evidence and quality of articles were judged based on The Oxford Centre for Evidence-based Medicine Levels of Evidence and the QualSyst. Outcomes were analyzed with Comprehensive Meta-Analysis V2 software, random effects models, and Hedge's G. Effects were examined at 0-4 months, up to 6 months, and > 6 months. Pre-specified sensitivity analyses were performed for 1) controlled trials vs. all studies and 2) ALSFRS-R bulbar, respiratory, and motor subscales. Heterogeneity of pooled outcomes was computed with the I2 statistic. Results: 16 studies and seven functional outcomes met inclusion for the meta-analysis. Of the outcomes explored, the ALSFRS-R demonstrated a favorable summary effect size and had acceptable heterogeneity and dispersion. While FIM scores demonstrated a favorable summary effect size, heterogeneity limited interpretations. Other outcomes did not demonstrate a favorable summary effect size and/or could not be reported due to few studies reporting outcomes. Conclusions: This study provides inconclusive guidance regarding exercise regimens to maintain function and quality of life in people with ALS due to study limitations (e.g., small sample size, high attrition rate, heterogeneity in methods and participants, etc.). Future research is warranted to determine optimal treatment regimens and dosage parameters in this patient population.

The Influence of Surgical Correction of Idiopathic Scoliosis on the Function of Respiratory Muscles.

Background and objective: It is important to introduce respiratory exercises to the therapy of patients after the surgical treatment of adolescent idiopathic scoliosis. Surgical correction is the best way to prevent hypoxia in scoliosis, but whether pulmonary rehabilitation increases the effectiveness of scoliosis surgery has not yet been confirmed. Therefore, the aim of the study was to evaluate the function of respiratory muscles after surgical correction of idiopathic scoliosis. Methods: The study involved 24 patients, aged 13.6 ± 0.6. Maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) were measured using the Mikro RPM. In all patients, before the procedure, 7 days after and 3 months after the procedure, the MIP and MEP were measured. Results: MIP was the lowest 7 days after the procedure; it was 45.28 cmH2O and was statistically significantly lower compared to the measurement before the procedure (p < 0.001) and 3 months after the procedure (p < 0.001). Conclusions: The degree of curvature of the spine before the procedure does not significantly affect initial values of the strength of respiratory muscles. The level of MIP is not dependent on the type of surgery.

Expiratory Muscle Strength Treatment for Refractory Chronic Cough: A Short-term Single Exercise Program.

OBJECTIVES: Patients with chronic cough are some of the most challenging to treat. This preliminary study is the first to examine the effects of a single exercise muscle strength training program to reduce cough severity in patients who failed other treatments. METHODS: A total of 19 females were included in this study, ranging from age 24 to 80. The maximum phonation time (MPT), laryngeal airway resistance (LAR), maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP), Voice Handicap Index-10, (VHI-10) and the Cough Severity Index (CSI) values were obtained pre- and post-treatment. ANOVA two-factor without replication was used to compare values pre- and post-treatment. RESULTS: MIP (Mean of 62.00 to a mean of 78.53) and MEP (Mean of 90.00 to a mean of 112.16) showed significant increase post-treatment. In addition, LAR (Mean of 73.30 to a mean of 60.67) and CSI (Mean of 19.37 to a mean of 15.00) significantly decreased post-treatment. General changes in pre- and post-treatment values were identified with MPT (Mean of 14.89 to a mean of 16.17) and VHI-10 (Mean of 8.00 to a mean of 6.76). A follow-up questionnaire indicated that the majority of patients felt their cough was better after 4 weeks. CONCLUSIONS: Muscle strength training provides a tool to aid in the control of cough for patients who are refractory to medical and other behavioral treatments. Improvement in cough may be associated with a reduction in subglottic pressure and increased air flow resulting in lower laryngeal airway resistance.

Occurrence and Effects on Weaning From Mechanical Ventilation of Intensive Care Unit Acquired and Diaphragm Weakness: A Pilot Study.

Purpose: Limb intensive care unit (ICU)-acquired weakness (ICUAW) and ICU acquired diaphragm weakness (DW) occur frequently in mechanically ventilated (MV) patients; their coexistence in cooperative and uncooperative patients is unknown. This study was designed to (1) describe the co-occurrence of the two conditions (2) evaluate the impact of ICUAW and DW on the ventilator-free days (VFDs) at 28 days and weaning success, and (3) assess the correlation between maximal inspiratory pressure (MIP) and thickening fraction (TFdi) in patients with DW. Methods: This prospective pilot study was conducted in a single-center on 73 critically ill MV patients. Muscle weakness was defined as a Medical Research Council score < 48 in cooperative patients or a bilateral mean simplified peroneal nerve test < 5.26 mV in uncooperative patients. Diaphragm dysfunction was defined as MIP < 30 cm H2O or as a TFdi < 29%. Weaning success was defined according to weaning according to a new definition (WIND). Results: Fifty-seven patients (78%) had ICUAW and 59 (81%) had DW. The coexistence of the two conditions occurred in 48 patients (65%), without association (χ2 = 1.06, p = 0.304). In the adjusted analysis, ICUAW was independently related to VFDs at 28-days (estimate difference 6 days, p = 0.016), and WIND (OR of 3.62 for having WIND different than short weaning), whereas DW was not. The linear mixed model showed a significant but weak correlation between MIP and TFdi (p < 0.001). Conclusion: This pilot study is the first to explore the coexistence of ICUAW and DW in both cooperative and uncooperative patients; a lack of association was found between DW and ICUAW when considering both cooperative and uncooperative patients. We found a strong correlation between ICUAW but not DW with the VFDs at 28 days and weaning success. A future larger study is warranted in order to confirm our results, and should also investigate the use of transdiaphragmatic twitch pressure measurement during bilateral anterior magnetic phrenic nerve stimulation for the diagnosis of DW.