Effects of 12 weeks of inspiratory muscle training and whole body vibration on the inflammatory profile, BDNF and muscular system in pre-frail elderly women: A randomized controlled trial.

AIM: to investigate the effects of the whole body vibration (WBV) and inspiratory muscle training (IMT) on the inflammatory profile and in muscle mass and strength in pre-frail older women. METHODS: this study was a randomized double-blind trial. Forty two older women aged 60-80 years were randomly allocated to IMT + WBV (G1), IMTsham + WBV (G2) or Sham groups (G3). During 12 weeks G1 received both trainings, whereas G2 received WBV alone and G3 received IMT with a low fixed load and were positioned at the vibratory platform without therapeutic effect. Participants were evaluated before and after the intervention for the following outcomes: Brain-derived neurotrophic factor (BDNF) and inflammatory biomarkers (IB), respiratory (RT) and quadriceps thickness (QT) and diaphragmatic mobility (DM) using muscle ultrasound, body composition (BC) using a bioelectrical impedance scale and inspiratory muscle strength (IMS). RESULTS: after the training, G1 (114.93 ± 21.29) improved IMS (p<0.005) compared with G2 (91.29 ± 23.10) and G3 (85.21 ± 27.02). There was also a significant improve on time of the DM (p<0.001) and RT (p=0.006) for G1 (8.59 ± 3.55 and 11.11 ± 12.66) compared with G2 (1.05 ± 3.09 and 1.10 ± 10.60) and G3 (0.40 ± 2.29 and -1.85 ± 7.45). BDNF, IB, QT and BC were similar between groups. CONCLUSIONS: IMT associated with WBV is effective to improve in increasing IMS, RT and DM in pre-frail older women. However, these interventions do not modify BDNF, IB, QT or BC in this population.

Incremental Ramp Load Protocol to Assess Inspiratory Muscle Endurance in Healthy Individuals: Comparison with Incremental Step Loading Protocol.

INTRODUCTION: Protocols for obtaíníng the maxímum threshold pressure have been applied wíth límited precision to evaluate ínspiratory muscle endurance. In thís sense, new protocols are needed to allow more relíable measurements. The purpose of the present study was to compare a new incremental ramp load protocol for the evaluation of ínspíratory muscle endurance wíth the most used protocol in healthy indíviduals. METHODS: This was a prospective cross-sectional study carried out ín a síngle center. Nínety-two healthy indíviduals (43 men [22 ± 3 years] and 49 women [22 ± 3 years]) were randomly allocated to perform: (i) íncremental ramp load protocol and (íí) íncremental step loadíng protocol. The sustained pressure threshold (or maximum threshold pressure), maximum threshold pressure/dynamic strength índex ratío, time untíl task faílure, as well as dífference between the mean heart rate of the last five mínutes of baselíne and the peak heart rate of the last 30 seconds of each protocol were measured. RESULTS: Incremental ramp load protocol wíth small íncreases in the load and starting from mínímum values of strength index was able to evaluate the inspiratory muscle endurance through the maxímum threshold pressure of healthy indívíduals. CONCLUSION: The present study suggests that the íncremental ramp load protocol is able to measure maximum threshold pressure in a more thorough way, wíth less progression and greater accuracy in the load stratification compared to the límited incremental step loading protocol and with a safe and expected cardiovascular response in healthy individuals.

Effect of diaphragmatic breathing training with visual biofeedback on respiratory function in patients with multiple rib fractures: A randomized-controlled study.

Objectives: The aim of this study was to investigate the effect of diaphragmatic breathing training with visual biofeedback on respiratory function in patients with multiple rib fractures. Patients and methods: Between June 2021 and October 2021, a total of 16 patients (15 males, 1 female; mean age: 49.50±11.85 years; range, 25 to 66 years) who were diagnosed with multiple rib fractures were randomly assigned into two groups as the control group (CG, n=8) and the visual biofeedback group (VBG, n=8). The effect of each diaphragmatic breathing training on respiratory function was evaluated before and after eight interventions. For respiratory function, pulmonary function test was used to measure pulmonary function and respiratory muscle strength, and the Pain, Inspiratory capacity, Cough (PIC) score was used to evaluated pain, inspiratory capacity, and cough ability. Results: In both groups, the pulmonary function representing the ratio of measurements to predicted values of both forced vital capacity (CG mean difference=25.37±4.58, p=0.002, VBG mean difference=24.25±3.96, p=0.007) and forced expiratory volume in 1 sec (CG mean difference=32.38±5.7, p=0.002, VBG mean difference=26.15±5.73, p <0.001) increased significantly. The maximal inspiratory (CG mean difference=14.00±0.35, p=0.002, VBG mean difference=20.5±6.26, p=0.009) and expiratory pressure (CG mean difference=43.72±29.44, p=0.034, VBG mean difference=25.76±6.78, p=0.015), the indicators of respiratory muscle strength, increased significantly in both groups. The PIC score, which evaluated pain, inspiratory capacity, and cough ability, also increased significantly in both groups (CG mean difference=1.63±0.26, p≤0.001, VBG mean difference=3.13±0.19, p <0.001). The change of PIC score after intervention did not significantly differ between the groups (F=1.439, p=0.250); however, there was a significant difference over time (F=38.476, p <0.001). The change of PIC scores differed over time between the groups (F=2.806 p=0.011). Conclusion: Diaphragmatic breathing training and diaphragmatic breathing training with visual biofeedback can improve pulmonary function, respiratory muscle strength, pain, inspiratory capacity, and cough ability in patients with multiple rib fractures.

Combined frequency domain near-infrared spectroscopy and diffuse correlation spectroscopy system for comprehensive metabolic monitoring of inspiratory muscles during loading.

Significance: Mechanical ventilation (MV) is a cornerstone technology in the intensive care unit as it assists with the delivery of oxygen in critically ill patients. The process of weaning patients from MV can be long and arduous and can lead to serious complications for many patients. Despite the known importance of inspiratory muscle function in the success of weaning, current clinical standards do not include direct monitoring of these muscles. Aim: The goal of this project was to develop and validate a combined frequency domain near-infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS) system for the noninvasive characterization of inspiratory muscle response to a load. Approach: The system was fabricated by combining a custom digital FD-NIRS and DCS system. It was validated via liquid phantom titrations and a healthy volunteer study. The sternocleidomastoid (SCM), an accessory muscle of inspiration, was monitored during a short loading period in fourteen young, healthy volunteers. Volunteers performed two different respiratory exercises, a moderate load and a high load, which consisted of a one-minute baseline, a one-minute load, and a six-minute recovery period. Results: The system has low crosstalk between absorption, reduced scattering, and flow when tested in a set of liquid titrations. Faster dynamics were observed for changes in blood flow index (BFi), and metabolic rate of oxygen (MRO2) compared with hemoglobin + myoglobin (Hb+Mb) based parameters after the onset of loads in males. Additionally, larger percent changes in BFi, and MRO2 were observed compared with Hb+Mb parameters in both males and females. There were also sex differences in baseline values of oxygenated Hb+Mb, total Hb+Mb, and tissue saturation. Conclusions: The dynamic characteristics of Hb+Mb concentration and blood flow were distinct during loading of the SCM, suggesting that the combination of FD-NIRS and DCS may provide a more complete picture of inspiratory muscle dynamics.

Association between computed tomography-quantified respiratory muscles and chronic obstructive pulmonary disease: a retrospective study.

BACKGROUND: This study examined the association between chest muscles and chronic obstructive pulmonary disease (COPD) and the relationship between chest muscle areas and acute exacerbations of COPD (AECOPD). METHODS: There were 168 subjects in the non-COPD group and 101 patients in the COPD group. The respiratory and accessory respiratory muscle areas were obtained using 3D Slicer software to analysis the imaging of  computed tomography (CT). Univariate and multivariate Poisson regressions were used to analyze the number of AECOPD cases during the preceding year. The cutoff value was obtained using a receiver operating characteristic (ROC) curve. RESULTS: We scanned 6342 subjects records, 269 of which were included in this study. We then measured the following muscle areas (non-COPD group vs. COPD group): pectoralis major (19.06 ± 5.36 cm2 vs. 13.25 ± 3.71 cm2, P < 0.001), pectoralis minor (6.81 ± 2.03 cm2 vs. 5.95 ± 1.81 cm2, P = 0.001), diaphragmatic dome (1.39 ± 0.97 cm2 vs. 0.85 ± 0.72 cm2, P = 0.011), musculus serratus anterior (28.03 ± 14.95 cm2 vs.16.76 ± 12.69 cm2, P < 0.001), intercostal muscle (12.36 ± 6.64 cm2 vs. 7.15 ± 5.6 cm2, P < 0.001), pectoralis subcutaneous fat (25.91 ± 13.23 cm2 vs. 18.79 ± 10.81 cm2, P < 0.001), paravertebral muscle (14.8 ± 4.35 cm2 vs. 13.33 ± 4.27 cm2, P = 0.007), and paravertebral subcutaneous fat (12.57 ± 5.09 cm2 vs. 10.14 ± 6.94 cm2, P = 0.001). The areas under the ROC curve for the pectoralis major, intercostal, and the musculus serratus anterior muscle areas were 81.56%, 73.28%, and 71.56%, respectively. Pectoralis major area was negatively associated with the number of AECOPD during the preceding year after adjustment (relative risk, 0.936; 95% confidence interval, 0.879-0.996; P = 0.037). CONCLUSION: The pectoralis major muscle area was negative associated with COPD. Moreover, there was a negative correlation between the number of AECOPD during the preceding year and the pectoralis major area.

Flow-resistive loading and diaphragmatic muscle function in term and preterm infants.

PURPOSE: We aimed to assess diaphragmatic function in term and preterm infants with and without history of bronchopulmonary dysplasia (BPD), before and after the application of inspiratory flow resistive loading. METHODS: Forty infants of a median (range) gestational age of 34 (25-40) weeks were studied. BPD was defined as supplemental oxygen requirement for >28 days of life. Seventeen infants were term, 17 preterm without history of BPD, and six preterm with a history of BPD. The diaphragmatic pressure-time index (PTIdi) was calculated as the mean to maximum trans-diaphragmatic pressure ratio times the inspiratory duty cycle. The PTIdi was calculated before and after the application of an inspiratory-flow resistance for 120 s. Airflow was measured by a pneumotachograph and the transdiaphragmatic pressure by a dual pressure catheter. RESULTS: The median (interquartile range [IQR]) pre-resistance PTIdi was higher in preterm infants without BPD (0.064 [0.050-0.077]) compared with term infants (0.052 [0.044-0.062], p = .029) and was higher in preterm infants with BPD (0.119 [0.086-0.132]) compared with a subgroup of preterm infants without BPD (0.062 [0.056-0.072], p = .004). The median (IQR) postresistance PTIdi was higher in preterm infants without BPD (0.101 [0.084-0.132]) compared with term infants (0.067 [0.055-0.083], p < .001) and was higher in preterm infants with BPD [0.201(0.172-0.272)] compared with the preterm subgroup without BPD (0.091 [0.081-0.108],p = .004). The median (IQR) percentage change of the PTIdi after the application of the resistance was higher in preterm infants without BPD (65 [51-92] %) compared with term infants (34 [20-39] %, p < .001). CONCLUSIONS: Preterm infants, especially those recovering from BPD, are at increased risk of diaphragmatic muscle fatigue under conditions of increased inspiratory loading.

Invasive versus non-invasive paediatric home mechanical ventilation: review of the international evolution over the past 24 years.

BACKGROUND: Home mechanical ventilation (HMV) is the treatment for chronic hypercapnic alveolar hypoventilation. The proportion and evolution of paediatric invasive (IMV) and non-invasive (NIV) HMV across the world is unknown, as well as the disorders and age of children using HMV. METHODS: Search of Medline/PubMed for publications of paediatric surveys on HMV from 2000 to 2023. RESULTS: Data from 32 international reports, representing 8815 children (59% boys) using HMV, were analysed. A substantial number of children had neuromuscular disorders (NMD; 37%), followed by cardiorespiratory (Cardio-Resp; 16%), central nervous system (CNS; 16%), upper airway (UA; 13%), other disorders (Others; 10%), central hypoventilation (4%), thoracic (3%) and genetic/congenital disorders (Gen/Cong; 1%). Mean age±SD (range) at HMV initiation was 6.7±3.7 (0.5-14.7) years. Age distribution was bimodal, with two peaks around 1-2 and 14-15 years. The number and proportion of children using NIV was significantly greater than that of children using IMV (n=6362 vs 2453, p=0.03; 72% vs 28%, p=0.048), with wide variations among countries, studies and disorders. NIV was used preferentially in the preponderance of children affected by UA, Gen/Cong, Thoracic, NMD and Cardio-Resp disorders. Children with NMD still receiving primary invasive HMV were mainly type I spinal muscular atrophy (SMA). Mean age±SD at initiation of IMV and NIV was 3.3±3.3 and 8.2±4.4 years (p<0.01), respectively. The rate of children receiving additional daytime HMV was higher with IMV as compared with NIV (69% vs 10%, p<0.001). The evolution of paediatric HMV over the last two decades consists of a growing number of children using HMV, in parallel to an increasing use of NIV in recent years (2020-2023). There is no clear trend in the profile of children over time (age at HMV). However, an increasing number of patients requiring HMV were observed in the Gen/Cong, CNS and Others groups. Finally, the estimated prevalence of paediatric HMV was calculated at 7.4/100 000 children. CONCLUSIONS: Patients with NMD represent the largest group of children using HMV. NIV is increasingly favoured in recent years, but IMV is still a prevalent intervention in young children, particularly in countries indicating less experience with NIV.

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.

Expiratory Muscle Activity Counteracts Positive End-Expiratory Pressure and Is Associated with Fentanyl Dose in Patients with Acute Respiratory Distress Syndrome.

Rationale: Hypoxemia during mechanical ventilation might be worsened by expiratory muscle activity, which reduces end-expiratory lung volume through lung collapse. A proposed mechanism of benefit of neuromuscular blockade in acute respiratory distress syndrome (ARDS) is the abolition of expiratory efforts. This may contribute to the restoration of lung volumes. The prevalence of this phenomenon, however, is unknown. Objectives: To investigate the incidence and amount of end-expiratory lung impedance (EELI) increase after the administration of neuromuscular blocking agents (NMBAs), clinical factors associated with this phenomenon, its impact on regional lung ventilation, and any association with changes in pleural pressure. Methods: We included mechanically ventilated patients with ARDS monitored with electrical impedance tomography (EIT) who received NMBAs in one of two centers. We measured changes in EELI, a surrogate for end-expiratory lung volume, before and after NMBA administration. In an additional 10 patients, we investigated the characteristic signatures of expiratory muscle activity depicted by EIT and esophageal catheters simultaneously. Clinical factors associated with EELI changes were assessed. Measurements and Main Results: We included 46 patients, half of whom showed an increase in EELI of >10% of the corresponding Vt (46.2%; IQR, 23.9-60.9%). The degree of EELI increase correlated positively with fentanyl dosage and negatively with changes in end-expiratory pleural pressures. This suggests that expiratory muscle activity might exert strong counter-effects against positive end-expiratory pressure that are possibly aggravated by fentanyl. Conclusions: Administration of NMBAs during EIT monitoring revealed activity of expiratory muscles in half of patients with ARDS. The resultant increase in EELI had a dose-response relationship with fentanyl dosage. This suggests a potential side effect of fentanyl during protective ventilation.

Relationship between motor dysfunction, the respiratory muscles and pulmonary function in stroke patients with hemiplegia: a retrospective study.

BACKGROUND: The interaction between motor dysfunction and respiratory functions in stroke patients with hemiplegia are not fully understood, particularly with regard to the relationship between changes in trunk control, balance, and daily activities, and changes in respiratory muscle strength and pulmonary volume. Investigating this relationship will facilitate the optimization of stroke rehabilitation strategies. METHODS: Clinical history data were collected from 134 patients to analyze the relationship between motor function scales scores and spirometric data. The data from 60 patients' data were used to evaluate the relationship between motor function scales scores and spirometric data at baseline and after 3-weeks rehabilitation. RESULTS: (1) Patients with lower scores on Trunk impairment Scale (TIS), Berg Balance Scale (BBS) and Barthel Index (BI) had weaker respiratory muscle strength and pulmonary function. (2) Stroke patients' BBS and BI scores showed differences between normal and unnormal maximal inspiratory pressure (MIP), but not in TIS. (3) Improvements in motor function led to promotion of enhanced respiratory function. Patient exhibited less MIP improvement at the severe level of TIS and BBS. CONCLUSIONS: Patients with hemiplegia exhibited diminished respiratory muscle strength and pulmonary function at a more severe motor dysfunction level. Impaired inspiratory muscle strength was associated with reduced balance ability and limitations in activities required for daily living. Enhanced motor function improved respiration and rehabilitation programs should prioritize the activation of diaphragm function to improve overall outcomes.

Effects of Pulmonary Rehabilitation on Respiratory Function and Thickness of the Diaphragm in Patients with Post-COVID-19 Syndrome: A Randomized Clinical Trial.

BACKGROUND: Rehabilitation is an effective method for improving the overall health of patients who have experienced the long-term effects of COVID-19. METHODS: The double-blind, randomized prospective study assessed the effectiveness of a 6-week rehabilitation program among post-COVID-19 patients. A total of 59 patients under treatment following COVID-19 were randomly divided into two groups. Both groups completed the same six-week comprehensive exercise training program supported by a respiratory muscle trainer (Threshold IMT) during out-patient sessions. The control group performed placebo IMT. Respiratory muscle strength, chest wall expansion, spirometry, and diaphragm ultrasonography measurements were taken before and after the six weeks. RESULTS: The applied rehabilitation program improved respiratory muscle strength in both the study and control groups (p < 0.001). There was a significant chest circumference increase in the study group (p < 0.001). Spirometric parameters improved in both groups, with the study group showing a greater improvement: 8.02% in FEV1 (p < 0.001), 13.24% in FVC EX (p < 0.001) and 9.67% in PEF (p < 0.001). Rehabilitation also increased diaphragm thickness during maximum inhalation in both groups. CONCLUSIONS: Based on the study findings, the specialized outpatient rehabilitation program developed for post-COVID-19 patients has proven to be effective and safe.

Normal values for maximal respiratory pressures in children and adolescents: A systematic review with meta-analysis.

BACKGROUND: The non-invasive assessment of maximal respiratory pressures (MRP) reflects the strength of the respiratory muscles. OBJECTIVE: To evaluate the studies which have established normative values for MRP in healthy children and adolescents and to synthesize these values through a meta-analysis. METHODS: The searches were conducted until October 2023 in the following databases: ScienceDirect, MEDLINE, CINAHL, SciELO, and Web of Science. Articles that determined normative values and/or reference equations for maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in children and adolescents published in English, Portuguese, or Spanish regardless of the year of publication were included. Two reviewers selected titles and abstracts, in case of conflict, a third reviewer was consulted. Articles that presented sufficient data were included to conduct the meta-analysis. RESULTS: Initially, 252 studies were identified, 28 studies were included in the systematic review and 19 in the meta-analysis. The sample consisted of 5798 individuals, and the MIP and MEP values were stratified by sex and age groups of 4-11 and 12-19 years. Values from females 4-11 years were: 65.8 cmH2O for MIP and 72.8 cmH2O for MEP, and for males, 75.4 cmH2O for MIP and 84.0 cmH2O for MEP. In the 12-19 age group, values for females were 82.1 cmH2O for MIP and 90.0 cmH2O for MEP, and for males, they were 95.0 cmH2O for MIP and 105.7 cmH2O for MEP. CONCLUSIONS: This meta-analysis suggests normative values for MIP and MEP in children and adolescents based on 19 studies.

Effects of non-invasive ventilation on sleep in chronic hypercapnic respiratory failure.

Chronic respiratory disease can exacerbate the normal physiological changes in ventilation observed in healthy individuals during sleep, leading to sleep-disordered breathing, nocturnal hypoventilation, sleep disruption and chronic respiratory failure. Therefore, patients with obesity, slowly and rapidly progressive neuromuscular disease and chronic obstructive airways disease report poor sleep quality. Non-invasive ventilation (NIV) is a complex intervention used to treat sleep-disordered breathing and nocturnal hypoventilation with overnight physiological studies demonstrating improvement in sleep-disordered breathing and nocturnal hypoventilation, and clinical trials demonstrating improved outcomes for patients. However, the impact on subjective and objective sleep quality is dependent on the tools used to measure sleep quality and the patient population. As home NIV becomes more commonly used, there is a need to conduct studies focused on sleep quality, and the relationship between sleep quality and health-related quality of life, in all patient groups, in order to allow the clinician to provide clear patient-centred information.

The Association Between Preoperative Inspiratory Muscle Training Variables and Postoperative Pulmonary Complications in Subjects With Esophageal Cancer.

BACKGROUND: Preoperative inspiratory muscle training (IMT) is frequently used in patients waiting for major surgery to improve respiratory muscle function and to reduce the risk of postoperative pulmonary complications (PPCs). Currently, the mechanism of action of IMT in reducing PPCs is still unclear. Therefore, we investigated the associations between preoperative IMT variables and the occurrence of PPCs in patients with esophageal cancer. METHODS: A multi-center cohort study was conducted in subjects scheduled for esophagectomy, who followed IMT as part of a prehabilitation program. IMT variables included maximum inspiratory pressure (PImax) before and after IMT and IMT intensity variables including training load, frequency, and duration. Associations between PImax and IMT intensity variables and PPCs were analyzed using independent samples t tests and logistic regression analyses, corrected for age and pulmonary comorbidities and stratified for the occurrence of anastomotic leakages. RESULTS: Eighty-seven subjects were included (69 males; mean age 66.7 ± 7.3 y). A higher PImax (odds ratio 1.016, P = .07) or increase in PImax during IMT (odds ratio 1.020, P = .066) was not associated with a reduced risk of PPCs after esophagectomy. Intensity variables of IMT were also not associated (P ranging from .16 to .95) with PPCs after esophagectomy. Analyses stratified for the occurrence of anastomotic leakages showed no associations between IMT variables and PPCs. CONCLUSIONS: This study shows that an improvement in preoperative inspiratory muscle strength during IMT and training intensity of IMT were not associated with a reduced risk on PPCs after esophagectomy. Further research is needed to investigate other possible factors explaining the mechanism of action of preoperative IMT in patients undergoing major surgery, such as the awareness of patients related to respiratory muscle function and a diaphragmatic breathing pattern.

Effect of respiratory training on swallowing function in swallowing disorders: a systematic review and meta-analysis.

PURPOSE: To determine the clinical efficacy of different respiratory training interventions on swallowing function in patients with swallowing disorders through the systematic review. METHODS: We reviewed the literature regarding the application of respiratory training therapy in patients with swallowing disorders, followed by a PRISMA search of published literature in five databases (PubMed, Web of Science, The Cochrane Library, CINAHL and EMBASE) in December 2022. Two reviewers performed study selection, quality evaluation, and risk of bias, followed by data extraction and detailed analysis. RESULTS: A total of six randomized controlled studies with a total sample size of 193 cases were included. Respiratory training improved swallowing safety (PAS (n = 151, SMD = 0.69, 95% CI - 1.11 to - 0.26, I2 = 36, p < 0.001)) and swallowing efficiency [residual (n = 63, SMD = 1.67, 95% CI - 2.26 to - 1.09, I2 = 23%, p < 0.001)] compared to control groups. The results of the qualitative analysis conducted in this study revealed that respiratory training enhanced hyoid bone movement but had no effect on swallowing quality of life. CONCLUSIONS: Respiratory training interventions may improve swallowing safety and efficiency in patients with dysphagia. However, the level of evidence is low, and there is a limited amount of research on the effectiveness and physiology of this intervention to improve swallowing function. In the future, there is a need to expand clinical studies, standardize measurement tools, and improve study protocols.

Development of respiratory care guidelines for Duchenne muscular dystrophy in the UK: key recommendations for clinical practice.

Significant inconsistencies in respiratory care provision for Duchenne muscular dystrophy (DMD) are reported across different specialist neuromuscular centres in the UK. The absence of robust clinical evidence and expert consensus is a barrier to the implementation of care recommendations in public healthcare systems as is the need to increase awareness of key aspects of care for those living with DMD. Here, we provide evidenced-based and/or consensus-based best practice for the respiratory care of children and adults living with DMD in the UK, both as part of routine care and in an emergency. METHODOLOGY: Initiated by an expert working group of UK-based respiratory physicians (including British Thoracic Society (BTS) representatives), neuromuscular clinicians, physiotherapist and patient representatives, draft guidelines were created based on published evidence, current practice and expert opinion. After wider consultation with UK respiratory teams and neuromuscular services, consensus was achieved on these best practice recommendations for respiratory care in DMD. RESULT: The resulting recommendations are presented in the form of a flow chart for assessment and monitoring, with additional guidance and a separate chart setting out key considerations for emergency management. The recommendations have been endorsed by the BTS. CONCLUSIONS: These guidelines provide practical, reasoned recommendations for all those managing day-to-day and acute respiratory care in children and adults with DMD. The hope is that this will support patients and healthcare professionals in accessing high standards of care across the UK.

Incremental Ramp Load Protocol to Assess Inspiratory Muscle Endurance in Healthy Individuals: Comparison with Incremental Step Loading Protocol

ABSTRACT Introduction: Protocols for obtaining the maximum threshold pressure have been applied with limited precision to evaluate inspiratory muscle endurance. In this sense, new protocols are needed to allow more reliable measurements. The purpose of the present study was to compare a new incremental ramp load protocol for the evaluation of inspiratory muscle endurance with the most used protocol in healthy individuals. Methods: This was a prospective cross-sectional study carried out in a single center. Ninety-two healthy individuals (43 men [22 ± 3 years] and 49 women [22 ± 3 years]) were randomly allocated to perform: (i) incremental ramp load protocol and (ii) incremental step loading protocol. The sustained pressure threshold (or maximum threshold pressure), maximum threshold pressure/dynamic strength index ratio, time until task failure, as well as difference between the mean heart rate of the last five minutes of baseline and the peak heart rate of the last 30 seconds of each protocol were measured. Results: Incremental ramp load protocol with small increases in the load and starting from minimum values of strength index was able to evaluate the inspiratory muscle endurance through the maximum threshold pressure of healthy individuals. Conclusion: The present study suggests that the incremental ramp load protocol is able to measure maximum threshold pressure in a more thorough way, with less progression and greater accuracy in the load stratification compared to the limited incremental step loading protocol and with a safe and expected cardiovascular response in healthy individuals.

Maximal Respiratory Pressure Reference Equations in Healthy Adults and Cut-off Points for Defining Respiratory Muscle Weakness

Introduction: Maximal inspiratory and expiratory pressures (PImax/PEmax) reference equations obtained in healthy people are needed to correctly interpret respiratory muscle strength. Currently, no clear cut-off points defining respiratory muscle weakness are available. We aimed to establish sex-specific reference equations for PImax/PEmax in a large sample of healthy adults and to objectively determine cut-off points for respiratory muscle weakness. Methods: A multicentre cross-sectional study was conducted across 14 Spanish centres. Healthy non-smoking volunteers aged 18–80 years stratified by sex and age were recruited. PImax/PEmax were assessed using uniform methodology according to international standards. Multiple linear regressions were used to obtain reference equations. Cut-off points for respiratory muscle weakness were established by using T-scores. Results: The final sample consisted of 610 subjects (314 females; 48 [standard deviation, SD: 17] years). Reference equations for PImax/PEmax included body mass index and a squared term of the age as independent variables for both sexes (p<0.01). Cut-off points for respiratory muscle weakness based on T-scores ≥2.5 SD below the peak mean value achieved at a young age were: 62 and 83cmH2O for PImax and 81 and 109cmH2O for PEmax in females and males, respectively. Conclusion: These reference values, based on the largest dataset collected in a European population to date using uniform methodology, help identify cut-off points for respiratory muscle weakness in females and males. These data will help to better identify the presence of respiratory muscle weakness and to determine indications for interventions to improve respiratory muscle function. (AU)