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

Effects of Inspiratory Muscle Training on Stress Urinary Incontinence in North African Women: A Randomized Controlled Trial

INTRODUCTION AND HYPOTHESIS

Pelvic floor muscles (PFMs) are involved in respiratory mechanisms. Additionally, stress urinary incontinence (SUI) can affect physical function. This randomized controlled trial was aimed at investigating the effects of inspiratory muscle training (IMT) on SUI severity, PFM function, and physical function in Tunisian women with SUI.

METHODS

Twenty-seven incontinent women were randomly assigned to either the experimental group or the control group. The following parameters were assessed: respiratory muscle strength (RMS; maximal inspiratory and expiratory pressures), SUI severity (Urogenital Distress Inventory-6; Incontinence Impact Questionnaire-7; pad test), PFM function (Modified Oxford Scale, electromyography, and endurance), and physical function (Timed Up & Go test; 6-min walk test; incremental shuttle walking test). IMT was conducted using threshold IMT.

RESULTS

The IMT program significantly reduced the severity of SUI (p < 0.01), improved PFM function (p < 0.001), enhanced physical function (p < 0.01), and increased RMS (p < 0.001).

CONCLUSION

Inspiratory muscle training could be an effective method for improving pelvic floor disorders and physical function in women with SUI.

Validation of a Low-Cost Manometer to Assess of Tongue, Lip, Cheek, and Respiratory Strength: A Laboratory-Based Study

OBJECTIVE(S)

The objective of this study was to characterize the level of agreement between three manometers: (1) Iowa Oral Performance Instrument (IOPI)-the reference standard for tongue, lip, and cheek strength assessments; (2) MicroRPM Respiratory Pressure Meter (MicroRPM)-the reference standard for respiratory strength assessments; and (3) Digital Pressure Manometer (DPM)-an alternative, low-cost pressure testing manometer.

METHODS

Manual pressures were simultaneously applied to the IOPI and DPM, and to the MicroRPM and DPM, within a controlled laboratory setting. Agreement in pressure readings were analyzed using descriptive statistics, Lin's concordance correlation, and Bland-Altman Plots. Agreement was interpreted as "poor" if ρc < 0.90, "moderate" if ρc = 0.90 - < 0.95, "substantial" if ρc = 0.95 - < 0.99, and "excellent" if ρc ≥ 0.99.

RESULTS

Differences in pressure readings between the DPM and clinical reference standards were consistently present yet highly predictable. There was a median absolute difference of 2.0-3.9 kPa between the IOPI and DPM, and 4.5-9.8 cm H2O between the MicroRPM and DPM. Lin's concordance revealed "substantial" agreement between the IOPI and DPM (ρc = 0.98) and the MicroRPM and DPM (ρc = 0.99).

CONCLUSION

The DPM revealed higher pressure readings when compared to the IOPI and MicroRPM. However, differences in pressure readings were relatively small, highly predictable, and yielded substantial overall agreement. These findings suggest the DPM may be a valid, lower-cost alternative for objective assessments of tongue, lip, cheek, and respiratory muscle strength. Future research should expand on the present findings in clinical patient populations.

LEVEL OF EVIDENCE

NA Laryngoscope, 2024.

Obesity-related reduced spirometry and altered breathing pattern are associated with mechanical disadvantage of the diaphragm

The aim of this study was to characterize the breathing patterns of individuals with obesity during routine activities such as sitting and standing, and to identify potential contributors to alterations in these patterns. Measurements performed in 20 male subjects with obesity (BMI, 31.8±1.5 kg/m2) and 20 controls (BMI, 23.5±1.4 kg/m2) included anthropometric parameters, breathing-patterns in sitting and standing positions, spirometry, maximal respiratory pressures, and diaphragm B-mode ultrasonography. Individuals with obesity exhibited lower tidal volume and increased respiratory rate to maintain a similar minute-ventilation (p<0.05). Subjects with obesity demonstrated impaired spirometry and respiratory muscle strength, with inspiratory functions being notably compromised (p<0.05). Individuals with obesity had a greater diaphragm thickness at end inspiration but lower thickening-fraction at end quiet and forced breathings and reduced diaphragmatic displacement and excursion during maximal breaths (p<0.05). BMI was negatively associated with all respiratory function markers (p<0.05). Individuals with obesity exhibit a higher respiratory rate but lower tidal volume, likely to accommodate decreased compliance and excess thoracic and abdominal fat, further hindering inspiratory function. Moreover, increased adiposity is associated with a thicker but weaker diaphragm, primarily due to the diaphragm's mechanical disadvantage rather than its intrinsic inability to generate force.

Investigation of Inspiratory Muscle Training Efficiency Before Bronchoscopic Lung Volume Reduction: A Randomized Controlled Trial

INTRODUCTION

Pulmonary rehabilitation (PR) is recommended prior to bronchoscopic lung volume reduction (BLVR) procedures to optimize patient outcomes. However, there's a lack of clear guidance on PR content. The aim of our study is to examine the effect of adding inspiratory muscle training (IMT) to standard PR before BLVR on exercise capacity, dyspnea, fatigue level and quality of life.

METHODS

Sixty-four patients were randomly assigned to either the PR Group (PRGr) or the PR with IMT group (IMTGr). Both groups underwent an 8-week standard PR program, including breathing exercises, muscle strengthening, and walking. Additionally, IMTGr received IMT sessions. Outcome measures comprised six-minute walking distance (6MWD), maximal inspiratory and expiratory pressures (MIP, MEP), peripheral muscle strength, modified Medical Research Council dyspnea score, fatigue symptom scale, spirometric parameters, Saint George Quality of Life Questionnaire (SGRQ), International Physical Activity Questionnaire Short Form (IPAQ-SF), and Hospital Anxiety and Depression Scale.

RESULTS

Our study found no significant difference in exercise capacity improvement between IMTGr and PRGr. However, IMTGr showed significant improvement in MIP compared to PRGr. Both groups experienced improvements in dyspnea, fatigue, and depression scores, as well as enhancements in 6MWD, MEP, peripheral muscle strength, IPAQ-SF and SGRQ scores.

CONCLUSION

Adding IMT to PR did not show a significant difference between groups among BLVR-eligible patients. However, improved respiratory muscle strength may have positive clinical implications. Further research is needed to explore short and long-term effects.

Using Inspiratory Muscle Training to Improve Respiratory Strength, Functional Capacity, Fatigue, and Stress in Breast Cancer Patients Undergoing Surgery

Purpose

The main aim of the trial was to assess the effectiveness of inspiratory muscle training on respiratory muscle strength, functional capacity, fatigue, and stress in post-surgical breast cancer survivors.

Methods

Forty-seven females who had undergone unilateral post-mastectomy were randomly assigned to an intervention group (IG; n = 24) and a control group (CG; n = 23). Both groups received aerobic exercise training. In addition, the intervention group received inspiratory muscle training 3 days a week for 8 weeks. Maximum inspiratory and expiratory pressure (Pimax) (Pemex), 6-minute walk test, Handgrip strength by hand-held dynamometer, Fatigue Assessment Scale (FAS), and Perceived Stress Scale pss 10 values were measured before the training and then at the eighth week for both groups.

Results

No differences were detected between the groups in terms of sample and clinical characteristics 8 weeks post-intervention. In favor of the intervention group, a significant difference with medium to high effect size was found in terms of Pimax, Pemax, FAS, PS, and 6MWT (p < 0.05). However, there was no difference in terms of handgrip strength (p-value: 0.072), with a medium effect size (0.070). Regarding within-group comparisons, IG exhibited substantial differences in all outcome measures (p < 0.05) compared to CG, with the exception of PImax and 6MWT.

Conclusion

In post-operative breast cancer survivors, respiratory muscle training combined with aerobic training increases respiratory muscle strength and functional ability while lowering stress and tiredness.

Definition, diagnosis, and treatment of respiratory sarcopenia

PURPOSE OF REVIEW

Skeletal muscle weakness and wasting also occurs in the respiratory muscles, called respiratory sarcopenia. Respiratory sarcopenia may lead to worse clinical indicators and outcomes. We present a novel definition and diagnostic criteria for respiratory sarcopenia, summarize recent reports on the association between respiratory sarcopenia, physical and nutritional status, and clinical outcomes, and provide suggestions for the prevention and treatment of respiratory sarcopenia.

RECENT FINDINGS

Recently, a novel definition and diagnostic criteria for respiratory sarcopenia have been prepared. Respiratory sarcopenia is defined as a condition in which there is both low respiratory muscle strength and low respiratory muscle mass. Respiratory muscle strength, respiratory muscle mass, and appendicular skeletal muscle mass are used to diagnose respiratory sarcopenia. Currently, it is challenging to definitively diagnose respiratory sarcopenia due to the difficulty in accurately determining low respiratory muscle mass. Decreased respiratory muscle strength and respiratory muscle mass are associated with lower physical and nutritional status and poorer clinical outcomes. Exercise interventions, especially respiratory muscle training, nutritional interventions, and their combinations may effectively treat respiratory sarcopenia. Preventive interventions for respiratory sarcopenia are unclear.

SUMMARY

The novel definition and diagnostic criteria will contribute to promoting the assessment and intervention of respiratory sarcopenia.