Respiratory Muscle Strength in Patients With Chronic Obstructive Pulmonary Disease

Pulmonary function trajectories in COVID-19 survivors with and without pre-existing respiratory disease

A significant proportion of COVID-19 survivors still experience a reduced diffusion capacity three and twelve months after discharge. We aimed to compare pulmonary function trajectories between hospitalized COVID-19 patients with pre-existing respiratory disease (PRD) and patients without pre-existing respiratory disease (Non-PRD) at three and twelve months after hospital discharge. This single-centre retrospective cohort study included COVID-19 patients admitted to the VieCuri Medical Centre (Venlo, the Netherlands) between February and December 2020 that were invited to the outpatient clinic at three and twelve months after discharge. During this visit, pulmonary function tests were performed and impairments were based on lower limit of normal. Data of 239 patients were analysed (65% male, 66 ± 10 years, and 26% with a history of respiratory disease). Three months after discharge, 49% and 64% of the Non-PRD patients (n = 177) and PRD patients (n = 62) had a low diffusion capacity, respectively. This improved over time in Non-PRD patients (p = 0.003), but not in PRD patients (p = 0.250). A low diffusion capacity was still observed in 34% and 57% of the Non-PRD and PRD group, respectively, twelve months after discharge. Pulmonary function impairments, mainly a reduced diffusion capacity, are observed among hospitalized COVID-19 patients with PRD and Non-PRD, at three and twelve months follow-up. Although diffusion capacity impairments restore over time in Non-PRD patients, poor recovery was observed among PRD patients.

Effect of 12-week head-down strong abdominal breathing on cognitive function in patients with stable chronic obstructive pulmonary disease: a single-centre randomised controlled trial protocol

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) often suffer from a combination of mild cognitive impairment (MCI) and a significant reduction in their quality of life. In the exercise programme of pulmonary rehabilitation (PR), pulmonary rehabilitation intervention is often carried out by enhancing respiratory function. Strong abdominal breathing is a kind of breathing method, through which the diaphragm can be exercised, thereby enhancing the deflection distance of the diaphragm during breathing and improving respiratory function. The inversion trainer can meet the different angles of head-down training and also has the characteristics of low cost, easy to operate, and use a wide range of scenarios. According to currently available data, strong abdominal breathing in combination with head-down position has not yet been used in pulmonary rehabilitation in this type of rehabilitation programme. It is valuable to use this device to study PR of cognitive function in patients with COPD.

METHODS

This study was a 12-week single-centre randomised controlled trial and blinding the assessors and data processors of the test. Recruitment is planned for January 1, 2024. It is expected that 81 patients with stable COPD combined with MCI will be recruited and randomly assigned to the head-down strong abdominal breathing group (HG), the fitness qigong eight-duanjin group (BDJ), and the control group (CG) in a 1:1:1 ratio. Using fNIRS (functional near-infrared spectroscopy) to assess brain oxygen availability before and after pulmonary rehabilitation in three periods: before, during and after the intervention. Cognitive functioning is also assessed using the Overall Cognitive Assessment Scale, the Specific Cognitive Functioning Assessment Scale and the Cognitive Behavioural Ability Test.

TRIAL REGISTRATION

The Specialised Committee on Scientific Research and Academic Ethics of the Academic Committee of Anqing Normal University approved the project (ANU2023001). China Clinical Trial Registry approved the study (ChiCTR2300075400) with a registration date of 2023/09/04.

DISCUSSION

The aim of this study was to explore novel exercise rehabilitation methods to improve cognitive function in COPD patients. It results in a lower financial burden and higher participation in pulmonary rehabilitation and improves the quality of survival of patients with COPD.

Respiratory muscle strength can improve the prognostic assessment in COPD

Impaired lung function, respiratory muscle weakness and exercise intolerance are present in COPD and contribute to poor prognosis. However, the contribution of the combination of these manifestations to define prognosis in COPD is still unknown. This study aimed to define cut-off points for both inspiratory and expiratory muscle strength (MIP and MEP, respectively) for mortality prediction over 42-months in patients with COPD, and to investigate its combination with other noninvasive established prognostic measures (FEV1, V̇O2peak and 6MWD) to improve risk identification. Patients with COPD performed pulmonary function, respiratory muscle strength, six-minute walk and cardiopulmonary exercise tests, and were followed over 42 months to analyze all-cause mortality. A total of 79 patients were included. The sample was mostly (91.1%) comprised of severe (n = 37) and very severe (n = 34) COPD, and 43 (54%) patients died during the follow-up period. Cut-points of ≤ 55 and ≤ 80 cmH2O for MIP and MEP, respectively, were associated with increased risk of death (log-rank p = 0.0001 for both MIP and MEP) in 42 months. Furthermore, MIP and MEP substantially improved the mortality risk assessment when combined with FEV1 (log-ranks p = 0.006 for MIP and p < 0.001 for MEP), V̇O2peak (log-rank: p < 0.001 for both MIP and MEP) and 6MWD (log-ranks: p = 0.005 for MIP; p = 0.015 for MEP). Thus, patients severely affected by COPD presenting MIP ≤ 55 and/or MEP ≤ 80 cmH2O are at increased risk of mortality. Furthermore, MIP and MEP substantially improve the mortality risk assessment when combined with FEV1, V̇O2peak and 6MWD in patients with COPD.

Functional Exercise Capacity and Perceived Exertion in Patients with Empty Nose Syndrome

Empty nose syndrome (ENS) is a complex condition characterized by symptoms such as dyspnea, nasal discomfort, and emotional challenges. This study aimed to evaluate functional exercise capacity and perceived exertion in patients with ENS. Patients with ENS who presented with a range of severe symptoms were prospectively enrolled. Pulmonary function was evaluated using spirometry, and functional exercise capacity was measured via the 6 min walk test (6-MWT). Perceived exertion was quantified using the Borg scale, and cardiopulmonary function was evaluated by monitoring peripheral oxygen saturation (SpO2). These parameters were assessed before and after nasal reconstruction surgery. A total of 44 patients with ENS were enrolled and classified into mild-to-moderate (n = 20) and severe (n = 24) symptom groups. Spirometry results showed no significant differences before and after surgery in the entire cohort. Perceived exertion showed significant postoperative improvement (p = 0.006). The severe ENS symptom group experienced significant improvement in SpO2 (p = 0.013) and perceived exertion (p = 0.002) at the end of the 6-MWT after surgery. Surgical intervention significantly enhanced functional exercise capacity (p = 0.038) in patients with mild-to-moderate ENS symptoms. Surgical reconstruction positively affected perceived exertion and SpO2 at the end of the 6-MWT in patients with ENS. The severity of ENS symptoms, as assessed by SNOT-25 scores, influenced these outcomes. These findings underscore the potential benefits of surgical intervention for enhancing exercise tolerance and respiratory efficiency.

Postoperative pulmonary complications in patients undergoing upper abdominal surgery: risk factors and predictive models

Postoperative pulmonary complications (PPCs) are unexpected disorders that occur up to 30 days after surgery, affecting the patient's clinical status and requiring therapeutic intervention. Therefore, it becomes important to assess the patient preoperatively, as many of these complications can be minimized with proper perioperative strategies following a thorough preoperative checkup. Herein, we describe the PPCs and risk factors associated with developing PPCs in patients undergoing upper abdominal surgery. Additionally, we compared the accuracy of the American Society of Anaesthesiologists (ASA) score, the Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score, the 6-Minute Walk Test (6MWT), and spirometry in predicting PPCs. Consenting patients (>18 years) undergoing elective upper abdominal surgery were recruited from November 2021 to April 2023. Clinical history was noted. Spirometry and 6MWT were both performed. Pre-operative ASA and ARISCAT scores were recorded. Postoperative follow-up was conducted to assess respiratory symptoms and the occurrence of PPC. PPC was defined as per EPCO guidelines. A total of 133 patients were recruited, predominantly male. A total of 27 (20.3%) patients developed PPCs. A total of 14 (10.5%) patients had more than one PPC. The most common PPCs developed were pleural effusion (11.3%), respiratory failure (7.5%), and pneumonia (4.5%). We obtained ten statistically significant associated variables on univariable analysis, viz obstructive airway disease (p=0.002), airflow limitation (p=0.043), chest radiography (p<0.001), albumin (p=0.30), blood urea nitrogen (BUN) (p=0.029), aspartate aminotransferase (p=0.019), alanine aminotransferase (p=0.009), forced expiratory volume in one second/forced vital capacity ratio (p=0.006), duration of surgery (p<0.001), and ASA score (p=0.012). On multivariable regression analysis, abnormal chest radiograph [odds ratio: 8.26; (95% confidence interval: 2.58-25.43), p<0.001], BUN [1.05; (1.00-1.09), p=0.033], and duration of surgery [1.44; (1.18-1.76), p<0.001] were found to be independently associated with PPC. The ASA score was found to have better predictive power for the development of PPCs compared to the ARISCAT score but is of poor clinical significance. Additionally, 6MWD and spirometry results were found to lack any meaningful predictive power for PPC. To conclude, preoperative evaluation of the chest radiograph, BUN, and duration of surgery are independently associated with developing PPCs. The ASA score performs better than the ARISCAT score in identifying patients at a higher risk of developing PPCs and implementing preventive measures.

Relationship between respiratory muscle strength and dynamic balance in older persons requiring care or support: Focusing on the maximal single step length test and maximal double step length test as dynamic balance indices

BACKGROUND

Falls are a major health problem. The relationship between dynamic balance related to falls and respiratory muscle strength related to sarcopenia and frailty is poorly understood.

RESEARCH QUESTION

How do dynamic balance measures, such as maximal single step length test (MSL) and maximal double step length test (MDST), and respiratory muscle strength measures, such as maximal inspiratory (PImax) and maximal expiratory (PEmax), related to the requirement for long-term care or support in older people who live in the community?

METHODS

This was a cross-sectional study of 39 older people (17 men, 22 women) aged ≥ 65 years community-dwelling who were certified as requiring long-term care or support under the Japanese system. The participants' PImax, PEmax, MSL, and MDST results were recorded. The measurement data were evaluated using Pearson's correlation coefficients and multiple regression analysis.

RESULTS

MDST showed a positive correlation with PImax (r = 0.430, p = 0.006) but no correlation with PEmax. MSL showed no correlation with PImax or PEmax. A positive correlation was found between MDST and MSL (r = 0.851, p < 0.001), and multiple regression analysis with MDST as the dependent variable and PImax and MST as independent variables showed significant differences for MSL (p < 0.001) and PImax (p = 0.027).

SIGNIFICANCE

In older people requiring long-term care or support, MDST had a greater association with inspiratory muscle strength compared with MSL. These results suggest the importance of inspiratory muscle strength training and MDST assessment in the prevention of falls in older people requiring long-term care or support.

Pulmonary rehabilitation improves exercise capacity, health-related quality of life, and cardiopulmonary function in patients with non-small cell lung cancer

BACKGROUND

Lung cancer significantly impairs exercise capacity and health-related quality of life (HRQL). Pulmonary rehabilitation (PR) has demonstrated positive effects on exercise capacity and HRQL in lung cancer patients. However, its impact on cardiopulmonary function needs further exploration. The aim of this study was to explore the effects of PR on cardiopulmonary function, exercise capacity and HRQL in patients with lung cancer.

METHODS

Patients with lung cancer were enrolled in a 12-week PR program. Each participant underwent a thorough evaluation, which included spirometry, cardiopulmonary exercise testing, respiratory muscle strength test, and evaluation of HRQL using the Chronic Obstructive Pulmonary Disease Assessment Test (CAT).

RESULTS

Fifty-six patients completed the PR program. Following PR, exercise capacity significantly improved, as evidenced by increased peak oxygen uptake and work rate (both p < 0.05). Exertional symptoms were notably reduced, including leg soreness and dyspnea at peak exercise, accompanied by a decrease in the CAT score (all p < 0.05). Furthermore, improvements in cardiopulmonary function were observed, encompassing respiratory muscle strength, ventilatory equivalent, tidal volume, stroke volume index, and cardiac index at peak exercise (all p < 0.05).

CONCLUSIONS

PR demonstrated notable enhancements in cardiopulmonary function, exertional symptoms, exercise capacity, and HRQL in patients with lung cancer.

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.

The short- and long-term effects of lower limb endurance training on outpatients with chronic obstructive pulmonary disease

OBJECTIVE

To explore the short- and long-term effects of lower-limb endurance training on chronic obstructive pulmonary disease outpatients.

DESIGN

Prospective quasi-experimental study.

SETTING

1383-bed teaching hospital in Taiwan.

PARTICIPANTS

Overall, 69 outpatients diagnosed with chronic obstructive pulmonary disease were enrolled. A total of 60 patients completed the study.

INTERVENTION

Training group: Lower-limb endurance training; control group: Education only.

MAIN MEASURES

The modified medical research council score, chronic obstructive pulmonary disease assessment test score, pulmonary function test, and number of acute exacerbation within a year.

RESULTS

The training group showed significant improvement in the chronic obstructive pulmonary disease assessment test total score, modified medical research council score (both P < 0.001) at third month sustaining to 12th month (P < 0.001) and presented less events of acute exacerbation (P = 0.011) at 12th month. The chronic obstructive pulmonary disease assessment test decreased by 8 points sustaining to 12th month. The training group presented significant post-training functional capacity improvements in 6-min walking distance, lowest oxygen saturation during 6-min walking test, peak workload, maximum inspiratory/ expiratory pressures, and calf circumference.

CONCLUSIONS

The lower-limb endurance training improved perceived dyspnea in daily activity and health status after completion of training and sustaining for a year. The lower-limb endurance training alleviated disease impacted on reduced acute exacerbations.

Effect of chest wall mobilization on respiratory muscle function in patients with severe chronic obstructive pulmonary disease (COPD): A randomized controlled trial

BACKGROUND

Clinical trials have demonstrated positive correlation between pulmonary function and chest wall expansion in COPD. Decrease in chest wall expansion in patients with COPD compromises rib cage mobility and functional length of respiratory muscles that ultimately jeopardize the efficacy and function of respiratory system.

METHOD

Thirty male adults (mean age: 74.97 ± 6.29) suffered with severe COPD were randomly allocated to either experimental group (chest wall mobilizations) or control group. Both groups received standardized education and walking exercise (twice/week) for 6 weeks. Patients in experimental group received additional chest wall mobilizations that include stretching and joints mobilization. Pulmonary function, respiratory muscle strength, thoracic excursion, cervical and thoracic range of movement were evaluated at baseline, post-program and at 3-month follow-up.

RESULTS

There were significantly greater improvements in respiratory muscle strength, thoracic excursion and thoracic range of movement (p < 0.01) except thoracic flexion. Lower thoracic excursion is strongly associated with increase in maximum inspiratory pressure (β = 13.64, p < 0.001) and maximum expiratory pressure (β = 16.23, p < 0.001). Thoracic range of movement especially extension (p < 0.001) and bilateral rotation (p < 0.01) exhibit a strong relationship with increase in lower thoracic excursion (adjusted R2 = 0.876) as shown in multiple regression analysis.

CONCLUSION

Additional chest wall mobilization in the rehabilitation of patients with COPD is likely to enhance thoracic extension and rotation which increase lower thoracic excursion. This significant improvement in chest expansion capacity allows respiratory muscles to work at an optimal functional length which result in greater respiratory muscle strength in patients with severe COPD.

Respiratory Muscle Strength and Aerobic Performance Among Chronic Obstructive Pulmonary Disease (COPD) Patients: A Correlational Study

Background Chronic obstructive pulmonary disease (COPD) is a heterogeneous lung condition, yielding various respiratory symptoms and categorized under several descriptors: early, mild, young, pre-COPD, and preserved ratio impaired spirometry. COPD is synonymous with symptoms such as dyspnea and cough, in addition to others like exercise intolerance, which result from respiratory muscle weakness. Therefore, the emergence of respiratory strength assessment tools for such patients is not surprising. However, evidence is limited regarding the impact of respiratory muscle strength on the physical performance of COPD patients. Therefore, this study employs the MicroRPM device (Medikart HealthCare Systems Pvt. Ltd., Delhi, India) to measure maximum inspiratory and expiratory pressure utilizing mouth pressure. Methodology We recruited a total of 40 patients for the study. All patients received a thorough assessment for hemodynamic stability and were categorized according to the Global Initiative for Chronic Obstructive Lung Disease criteria of COPD. The patients then underwent a training session for the MicroRPM device. We took each patient's inspiratory and expiratory pressure measurements, then determined their six-minute walk distance and modified the Borg scale rating. Results We observed no significant correlation between maximum inspiratory pressure (Pimax) and six-minute walk distance (r=-0.023, p=0.890) or modified Borg scale (r=-0.044, p=0.788); additionally, the correlation between maximum expiratory pressure (Pemax) and modified Borg scale was not significant (r=-0.192, p=0.235). However, the correlation between Pemax and six-minute walk distance was both negative and significant (r=-0.384, p=0.014). Conclusion Based on our results, respiratory muscle strength can influence the aerobic performance of COPD patients.

Respiratory sarcopenia: A position paper by four professional organizations

We defined respiratory sarcopenia as a coexistence of respiratory muscle weakness and decreased respiratory muscle mass. Although respiratory muscle function is indispensable for life support, its evaluation has not been included in the regular assessment of respiratory function or adequately evaluated in clinical practice. Considering this situation, we prepared a position paper outlining basic knowledge, diagnostic and assessment methods, mechanisms, involvement in respiratory diseases, intervention and treatment methods, and future perspectives on respiratory sarcopenia, and summarized the current consensus on respiratory sarcopenia. Respiratory sarcopenia is diagnosed when respiratory muscle weakness and decreased respiratory muscle mass are observed. If respiratory muscle mass is difficult to measure, we can use appendicular skeletal muscle mass as a surrogate. Probable respiratory sarcopenia is defined when respiratory muscle weakness and decreased appendicular skeletal muscle mass are observed. If only respiratory muscle strength is decreased without a decrease in respiratory function, the patient is diagnosed with possible respiratory sarcopenia. Respiratory muscle strength is assessed using maximum inspiratory pressure and maximum expiratory pressure. Ultrasonography and computed tomography are commonly used to assess respiratory muscle mass; however, there are insufficient data to propose the cutoff values for defining decreased respiratory muscle mass. It was jointly prepared by the representative authors and authorized by the Japanese Society for Respiratory Care and Rehabilitation, Japanese Association on Sarcopenia and Frailty, Japanese Society of Respiratory Physical Therapy and Japanese Association of Rehabilitation Nutrition. Geriatr Gerontol Int 2023; 23: 5-15.

Tailored patient self-management and supervised, home-based, pulmonary rehabilitation for mild and moderate chronic obstructive pulmonary disease

[Purpose] Our study aimed to estimate the effects of a supervised, intensive, home-based-pulmonary-rehabilitation (HBPR) program for mild and moderate chronic-obstructive-pulmonary-disease (COPD) patients. [Participants and Methods] A retrospective, case-control study. Forty-three (N=43) patients were observed, divided into Treatment-Group (TG) and Control-Group (CG). The TG (N=23) underwent a 4-week training program, consisting of endurance and strength training sessions, performed 4-times per week. In addition, inspiration muscle training was performed, with a threshold device. The primary outcome was dyspnea improvements, measured by the modified-Borg-scale (mBS), and the secondary outcome was the determination of diaphragm excursion and function, using ultrasound (US) assessment to measure clinical parameters. [Results] The results suggested significantly improved mBS scores, measured for the ΔT0-T1 and ΔT0-T2 time points; improved diaphragm-excursion (Dia-Ex) at ΔT0-T1 and ΔT0-T2; and improved maximum Dia-Ex at ΔT0-T1 and ΔT1-T2 in the TG compared with the CG. Moreover, the results showed improvements over time for all parameters in the TG versus CG, suggesting a constant improvement in respiratory pathology. [Conclusion] A supervised HBPR plan was effective in reducing dyspnea by the mBS, and improving diaphragmatic function, as determined by US evaluation, and lastly improving quality of life in patients with mild-to-moderate COPD.

Virtual Reality Technology Combined with Comprehensive Pulmonary Rehabilitation on Patients with Stable Chronic Obstructive Pulmonary Disease

With the popularization of medical knowledge and the development of medical technology, people pay more and more attention to COPD. This paper mainly studies the effect of virtual reality technology combined with comprehensive lung rehabilitation on patients with stable chronic obstructive pulmonary disease. 60 patients with stable chronic obstructive pulmonary disease were selected to collect their general information, such as name, gender, and age. They were divided into the experimental group and control group, 30 patients in each group. The experimental group was treated with virtual reality technology combined with lung rehabilitation, while the control group was treated with conventional rehabilitation. Patients in both groups needed medication and participated in a 30-minute disease description activity once a week. In addition, patients in the control group should walk for 20 minutes every day to monitor muscle fatigue. Breathing exercises are also carried out regularly. Patients are instructed to use their lips and abdomen for 5 minutes each time. The respiratory rate was 7 beats per minute. In addition to the routine training of the control group, the experimental group will also train the simulated bicycle for 20 minutes, which will be automatically saved on the computer after the training. After the experiment, the muscle function and motor ability of the two groups were evaluated, and the results were statistically analyzed. The total self-efficacy scores of patients before and after telemedicine technical support increased significantly (2.15 ± 0.21 before telemedicine technical support, 2.39 ± 0.20 after telemedicine technical support), and the difference was statistically significant (P < 0.05). The results show that the application of virtual reality technology can improve the rehabilitation belief of patients and strengthen the training effect.

Respiratory Muscle Performance Screening for Infectious Disease Management Following COVID-19: A Highly Pressurized Situation

The 2019-2020 coronavirus pandemic elucidated how a single highly infectious virus can overburden health care systems of even highly economically developed nations. A leading contributor to these concerning outcomes is a lack of available intensive care unit (ICU) beds and mechanical ventilation support. Poorer health is associated with a higher risk for severe respiratory complications from the coronavirus. We hypothesize that impaired respiratory muscle performance is an underappreciated factor contributing to poor outcomes unfolding during the coronavirus pandemic. Although impaired respiratory muscle performance is considered to be rare, it is more frequently encountered in patients with poorer health, in particular obesity. However, measures of respiratory muscle performance are not routinely performed in clinical practice, including those with symptoms such as dyspnea. The purpose of this article is to discuss the potential role of respiratory muscle performance from the perspective of the coronavirus pandemic. We also provide a theoretical patient management model to screen for impaired respiratory muscle performance and intervention, if identified, with the goal of unburdening health care systems during future pandemic crises.

Thoracic mobility and its relation to pulmonary function and rib-cage deformity in patients with early onset idiopathic scoliosis: a long-term follow-up

STUDY DESIGN

A group of adult patients with idiopathic scoliosis, diagnosed before the age of ten, at a mean of 26.5 years after treatment with either brace or surgery during childhood and adolescence attended a clinical follow-up.

OBJECTIVES

To evaluate the relation between thoracic mobility, rib-cage deformity, and pulmonary function. Long-term studies of pulmonary function in relation to thoracic mobility after treatment in this patient group have not been published.

METHODS

A total of 106 patients, 57 braced and 49 operated patients, attended the follow-up. We examined thoracic mobility (range of motion of the thoracic spine, thorax expansion, and breathing movements) and rib-cage deformity (curve size and trunk deformity) as well as pulmonary function, especially total lung capacity (TLC). Respiratory muscle strength was evaluated in a subgroup.

RESULTS

Thoracic range of motion was significantly less among the surgically treated patients compared with both the brace-treated and comparison group. Thorax expansion and breathing movements during maximal breathing were significantly reduced in the scoliotic patients compared with the reference values, with no significant differences between the treatment groups. The brace-treated group had better pulmonary function than the operated group, as measured by the TLC, forced vital capacity (FVC), and forced expiratory volume in one second (FEV1) (percentage of predicted values). The respiratory muscle strength was significantly lower only in the surgically treated patients when compared with reference values. The results of a multivariate analysis revealed that the strongest factors explaining TLC percentage of predicted were gender, brace model, and smoking habits.

CONCLUSIONS

Thoracic mobility was significantly reduced at mean 26.5 years after completed treatment in both brace-treated and surgically treated patients with early onset scoliosis, compared with the reference values, which did not influence TLC as strongly as gender, brace model, and smoking habits.

LEVELS OF EVIDENCE

Level III.

Cardiopulmonary Endurance of Hospitalized Older Adults With Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) could lead to poor cardiopulmonary endurance, which affects quality of life and increases the risk of rehospitalization or mortality. However, studies investigating associated factors of cardiopulmonary endurance for COPD inpatients are scant.

OBJECTIVE

The aim of the study was to investigate whether and how age, gender, COPD severity, body composition, dyspnea, respiratory muscle strength, and lower limb muscle strength and endurance were related to cardiopulmonary endurance in elderly inpatients with COPD.

METHODS

This was a cross-sectional study using a systematic sampling of older inpatients. Data of demographic characteristics such as age, gender, and disease severity were collected, and body mass index was calculated. Degrees of dyspnea were assessed by the modified Medical Research Council Dyspnea Scale. Respiratory muscle strength was reflected by the maximal inspiratory pressure and the maximal expiratory pressure. Lower limb muscle strength and endurance were assessed by a handheld dynamometer and a 30-second sit-to-stand test, respectively. Finally, cardiopulmonary endurance was assessed by a 6-minute walk test.

RESULTS

A total of 83 older COPD inpatients participated. The mean age was 74.01 ± 6.93 years. Cardiopulmonary endurance was associated with age, COPD severity, dyspnea, respiratory muscle strength, lower limb muscle strength, and endurance. Predictors of cardiopulmonary endurance were disease severity, dyspnea, and lower limb muscle endurance. These predictors explained 53% of the variance in cardiopulmonary endurance in older inpatients with COPD.

DISCUSSION

Cardiopulmonary endurance of hospitalized older adults with COPD should be strengthened by improving conditions of disease severity, dyspnea, and lower limb muscle endurance.

Effects of inspiratory muscle strength and inspiratory resistance on neck inspiratory muscle activation during controlled inspirations

NEW FINDINGS

What is the central question of this study? What factors influence the onset and magnitude of activation of the neck inspiratory muscles during inspiration? What is the main finding and its importance? Recruitment of the sternocleidomastoid and scalene muscles during inspiration, measured by means of surface EMG, was strongly correlated with maximal inspiratory pressure. This result indicates that muscle recruitment depends on the capacity of an individual to generate inspiratory pressure. Surface measurements of neck inspiratory muscle EMG activity might complement tests currently used for the screening of respiratory-related disease.

ABSTRACT

The aims of the present study were as follows: (i) to examine the relationship between the onset of recruitment of the neck inspiratory muscles and inspiratory muscle strength; and (ii) to clarify the effect of inspiratory resistance on neck inspiratory muscle activation during inspiration at specific flow rates and to specific lung volumes. Inspiratory muscle strength, as indicated by maximal inspiratory pressure (MIP), and peak inspiratory flow rate (PFR) were measured in healthy participants. Subsequently, participants inspired at target inspiratory flow rates between 20 and 100% of PFR as closely as possible, with and without artificial inspiratory resistance. Electromyographic activity (EMG_RMS ) of the sternocleidomastoid and scalene muscles was measured from surface electrodes at each target flow rate for each 10% increment of forced vital capacity (FVC) between 20 and 50% of FVC. Recruitment onset for each muscle was determined from %PFR-EMG_RMS curves at each lung volume (%FVC). Finally, linear regression analyses were performed for MIP and recruitment onset for each muscle at each %FVC. Recruitment onset during inspiration without inspiratory resistance was strongly correlated with MIP (r > 0.60, P < 0.040). Specifically, a lower MIP was associated with earlier muscle recruitment (i.e. recruitment at a lower flow rate), especially for the sternocleidomastoid muscle (r > 0.75, P < 0.005). Recruitment of both neck inspiratory muscles at a given flow rate was also earlier when inspiratory resistance was added (P = 0.002). These results indicate that the recruitment and activation of the neck inspiratory muscles depends on both inspiratory muscle strength and inspiratory resistance.

Reliability and validity of the test of incremental respiratory endurance measures of inspiratory muscle performance in COPD

Purpose

The Test of Incremental Respiratory Endurance (TIRE) provides a comprehensive assessment of inspiratory muscle performance by measuring maximal inspiratory pressure (MIP) over time. The integration of MIP over inspiratory duration (ID) provides the sustained maximal inspiratory pressure (SMIP). Evidence on the reliability and validity of these measurements in COPD is not currently available. Therefore, we assessed the reliability, responsiveness and construct validity of the TIRE measures of inspiratory muscle performance in subjects with COPD.

Patients and methods

Test-retest reliability, known-groups and convergent validity assessments were implemented simultaneously in 81 male subjects with mild to very severe COPD. TIRE measures were obtained using the portable PrO2 device, following standard guidelines.

Results

All TIRE measures were found to be highly reliable, with SMIP demonstrating the strongest test-retest reliability with a nearly perfect intraclass correlation coefficient (ICC) of 0.99, while MIP and ID clustered closely together behind SMIP with ICC values of about 0.97. Our findings also demonstrated known-groups validity of all TIRE measures, with SMIP and ID yielding larger effect sizes when compared to MIP in distinguishing between subjects of different COPD status. Finally, our analyses confirmed convergent validity for both SMIP and ID, but not MIP.

Conclusion

The TIRE measures of MIP, SMIP and ID have excellent test-retest reliability and demonstrated known-groups validity in subjects with COPD. SMIP and ID also demonstrated evidence of moderate convergent validity and appear to be more stable measures in this patient population than the traditional MIP.

EVALUATION OF FUNCTIONAL CONDITION OF RESPIRATORY MUSCLES OF PATIENTS WITH A COMPLICATED BRONCHIAL ASTHMA PATHOLOGY AND CHRONIC OBSTRUCTIVE PULMONARY DISEASES

The aim of the research was to study the functional state of respiratory muscles and neuro-respiratory drive in patients with a combined pathology of bronchial asthma and chronic obstructive pulmonary disease. The functional condition of the respiratory muscles and the tone of the respiratory centre were determined with the help of a device for occlusion spirometry. Also, the patient was observed with a spirometry, a general plethysmography of the body. Materials and methods. 140 patients with combined broncho-obstructive pathology, 34 patients with asthma and 17 patients with COPD were examined. Spirometry, general plethysmography of the body and occlusion spirometry were provided for all patients. Results show a decrease in muscle strength of breath in all categories of patients with broncho-obstructive diseases, especially expressed in patients with bronchial asthma and asthma-COPD intersection. The muscle strength of breath was maintained with a significant increase in COPD patients compared with those with bronchial asthma. With increasing broncho-obstruction in patients with asthma-COPD intersection, there was a progressive and reliable decrease in muscle strength for breath and expiration, as well as a tendency to increase neuron respiratory drive. In patients with asthma-COPD intersection with more expressed symptoms revealed a significant and reliable weakening of muscle strength for breath and increased neuro-respiratory drive. During the work were obtained reliable links of the parameters of respiratory muscle strength not only with the parameters of pulmonary volume and bronchial patency, but also with the degree of neutrophilic inflammation in this category of patients. Conclusions The obtained data on failure of the functional state of the respiratory muscles and the neuro-respiratory drive can be used in the development of rehabilitation programs for the management of patients with combined broncho-obstructive pathology.