Diaphragmatic excursion correlates with exercise capacity and dynamic hyperinflation in COPD patients

Inspiratory Muscle Training Before Esophagectomy Increases Diaphragmatic Excursion: A Randomized Controlled Trial

BACKGROUND

Inspiratory muscle training (IMT) has preventive effects against postoperative pulmonary complications (PPCs) after upper abdominal surgery. However, its impact on diaphragmatic function has not been evaluated. This study investigated the effect of preoperative IMT on diaphragmatic excursion (DE) and prevention of PPCs for patients with esophageal cancer.

METHODS

This study was an unblinded, parallel, randomized controlled trial. Patients with thoracic or abdominal esophageal cancer scheduled for esophagectomy were randomized into the incentive spirometry (IS) or IMT group. During preoperative neoadjuvant chemotherapy, IS or IMT intervention was performed. The inspiratory resistance of the IMT group was consistently set at 50% maximal inspiratory pressure. The primary outcome was the amount of change in DE evaluated with ultrasonography, and the secondary outcome was the incidence of Clavien-Dindo grade II or higher PPCs.

RESULTS

This study recruited 42 patients. Among these patients 21 were randomized into the IS or IMT group, and 2 patients dropped out from the study. Finally, 40 patients were included in this analysis. The DE of the IMT group increased significantly after the intervention. The IMT group had significantly larger DE changes than the IS group. Of the 39 patients analyzed for postoperative outcome, 5 experienced grade II PPCs. The IMT group had a lower incidence of PPCs than the IS group.

CONCLUSIONS

Patients with thoracic and abdominal esophageal cancer scheduled for surgery who had preoperative IMT have increased DE, which may have an important role in prevention of PPCs.

The Application of Diaphragm Ultrasound in Chronic Obstructive Pulmonary Disease: A Narrative Review

Chronic Obstructive Pulmonary Disease (COPD) is a prevalent condition that poses a significant burden on individuals and society due to its high morbidity and mortality rates. The diaphragm is the main respiratory muscle, its function has a direct impact on the quality of life and prognosis of COPD patients. This article aims to review the structural measurement and functional evaluation methods through the use of diaphragmatic ultrasound and relevant research on its application in clinical practice for COPD patients. Thus, it serves to provide valuable insights for clinical monitoring of diaphragm function in COPD patients, facilitating early clinical intervention and aiding in the recovery of diaphragm function.

Ultrasonography as a way of evaluating the diaphragm muscle in patients with chronic obstructive pulmonary disease

The respiratory muscles in chronic obstructive pulmonary disease (COPD) patients have reduced strength and resistance, leading to loss of the functional ability of these muscles. Lung hyperinflation is one of the main alterations, and air trapping is the main factor limiting diaphragmatic mobility (DM) in these patients; however, its correlation with functional parameters, exercise capacity, and indicators of disease severity remains underexplored. This study aimed to assess DM in stable COPD patients and relate the findings with parameters such as the 6-minute walk test distance, forced expiratory volume in 1 second (FEV1) %predicted, residual volume (RV) %predicted, and dyspnea. An observational cohort study was conducted to measure DM using ultrasound both at rest (DMrest) and during deep inspiration (DMmax). Forty-nine patients with stable COPD were included in this study. There was a correlation between DMmax and FEV1 %predicted (R = 0.36; P = .012), RV %predicted (r = -0.42; P = .01), RV/total lung capacity (r = -0.61; P < .001), and distance reached in the 6MWT (R = 0.46; P = .001). Patients with a modified Medical Research Council score <2 exhibited greater DM than those with a score ≥2 (mean difference = 13.20 ± 4.6 mm; P = .0059). Similarly, patients with a Body Mass Index, Airflow Obstruction, Dyspnea and Exercise Capacity index ≤4 showed greater DM (61.95 mm) than those with a Body Mass Index, Airflow Obstruction, Dyspnea and Exercise Capacity index >4 (47.89 mm; mean difference = 14.05 ± 5.3 mm; 95% confidence interval = 25.09-3.01 mm). DM is correlated with bronchial obstruction (FEV1), lung hyperinflation (RV and RV/total lung capacity), exercise capacity, and dyspnea in patients with COPD, suggesting its utility as an evaluative tool in this population.

Improvement of diaphragmatic excursion in the supine position in a patient with idiopathic pleuroparenchymal fibroelastosis: A case report

Idiopathic pleuroparenchymal fibroelastosis (iPPFE) is a rare form of idiopathic interstitial pneumonia. We report a case of a patient with iPPFE in whom postural changes improved diaphragmatic excursion (DE) and exercise tolerance. Chest radiography showed a greater elevation of the diaphragm at maximum expiration in the supine position than the standing position. DE measured by ultrasonography was higher in the supine position than the standing position. The findings may suggest greater diaphragm movement in the supine position, leading to successful rehabilitation and improved exercise endurance. There is no effective treatment for iPPFE; therefore, an innovative treatment strategy is warranted.

Ultrasound assessment of diaphragmatic dysfunction in non-critically ill patients: relevant indicators and update

Diaphragm dysfunction (DD) can be classified as mild, resulting in diaphragmatic weakness, or severe, resulting in diaphragmatic paralysis. Various factors such as prolonged mechanical ventilation, surgical trauma, and inflammation can cause diaphragmatic injury, leading to negative outcomes for patients, including extended bed rest and increased risk of pulmonary complications. Therefore, it is crucial to protect and monitor diaphragmatic function. Impaired diaphragmatic function directly impacts ventilation, as the diaphragm is the primary muscle involved in inhalation. Even unilateral DD can cause ventilation abnormalities, which in turn lead to impaired gas exchange, this makes weaning from mechanical ventilation challenging and contributes to a higher incidence of ventilator-induced diaphragm dysfunction and prolonged ICU stays. However, there is insufficient research on DD in non-ICU patients, and DD can occur in all phases of the perioperative period. Furthermore, the current literature lacks standardized ultrasound indicators and diagnostic criteria for assessing diaphragmatic dysfunction. As a result, the full potential of diaphragmatic ultrasound parameters in quickly and accurately assessing diaphragmatic function and guiding diagnostic and therapeutic decisions has not been realized.

Diaphragm Ultrasound in Different Clinical Scenarios: A Review with a Focus on Older Patients

Diaphragm muscle dysfunction is increasingly recognized as a fundamental marker of several age-related diseases and conditions including chronic obstructive pulmonary disease, heart failure and critical illness with respiratory failure. In older individuals with physical frailty and sarcopenia, the loss of muscle mass and function may also involve the diaphragm, contributing to respiratory dysfunction. Ultrasound has recently emerged as a feasible and reliable strategy to visualize diaphragm structure and function. In particular, it can help to predict the timing of extubation in patients undergoing mechanical ventilation in intensive care units (ICUs). Ultrasonographic evaluation of diaphragmatic function is relatively cheap, safe and quick and can provide useful information for real-time monitoring of respiratory function. In this review, we aim to present the current state of scientific evidence on the usefulness of ultrasound in the assessment of diaphragm dysfunction in different clinical settings, with a particular focus on older patients. We highlight the importance of the qualitative information gathered by ultrasound to assess the integrity, excursion, thickness and thickening of the diaphragm. The implementation of bedside diaphragm ultrasound could be useful for improving the quality and appropriateness of care, especially in older subjects with sarcopenia who experience acute respiratory failure, not only in the ICU setting.

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.

Detection of dynamic lung hyperinflation using cardiopulmonary exercise testing and respiratory function in patients with stable cardiac disease: a multicenter, cross-sectional study

BACKGROUND

Many patients with heart disease potentially have comorbid chronic obstructive pulmonary disease (COPD); however, there are not enough opportunities for screening, and the qualitative differentiation of shortness of breath (SOB) has not been well established. We investigated the detection rate of SOB based on a visual and qualitative dynamic lung hyperinflation (DLH) detection index during cardiopulmonary exercise testing (CPET) and assessed potential differences in respiratory function between groups.

METHODS

We recruited 534 patients with heart disease or patients who underwent simultaneous CPET and spirometry (369 males, 67.0 ± 12.9 years) to scrutinize physical functions. The difference between inspiratory and expiratory tidal volume was calculated (TV E-I) from the breath-by-breath data. Patients were grouped into convex (decreased TV E-I) and non-convex (unchanged or increased TV E-I) groups based on their TV E-I values after the start of exercise.

RESULTS

Among the recruited patients, 129 (24.2%) were categorized in the convex group. There was no difference in clinical characteristics between the two groups. The Borg scale scores at the end of the CPET showed no difference. VE/VCO2 slope, its Y-intercept, and minimum VE/VCO2 showed no significant difference between the groups. In the convex group, FEV1.0/FVC was significantly lower compared to that in the non-convex group (69.4 ± 13.1 vs. 75.0 ± 9.0%). Moreover, significant correlations were observed between FEV1.0/FVC and Y-intercept (r=-0.343), as well as between the difference between minimum VE/VCO2 and VE/VCO2 slope (r=-0.478).

CONCLUSIONS

The convex group showed decreased respiratory function, suggesting a potential airway obstruction during exercise. A combined assessment of the TV E-I and Y-intercept of the VE/VCO2 slope or the difference between the minimum VE/VCO2 and VE/VCO2 slopes could potentially detect COPD or airway obstruction.

Correlation Between Diaphragmatic Excursion and Exercise Tolerance Improvement Following Pulmonary Rehabilitation in Patients with Chronic Obstructive Pulmonary Disease-Obstructive Sleep Apnea Overlap Syndrome

Purpose

We assess the predictive value of diaphragm excursion (DE) in enhancing exercise tolerance following pulmonary rehabilitation (PR) among patients with COPD-OSA overlap syndrome.

Material and Methods

This prospective cohort study enrolled 63 patients diagnosed with COPD-OSA overlap syndrome who actively participated in a PR program from January 2021 to May 2023. Among these, 58 patients successfully completed the 20-week PR program, with exercise tolerance assessed through the measurement of six-minute walk distance (6MWD), and DE evaluated by ultrasonography. The responder to PR in terms of exercise ability was defined as a patient who showed an increase of >30m in 6MWD. The cutoff value for predicting PR response based on DE was determined using receiver operating characteristic (ROC) curves.

Results

Following the PR program, significant improvements were observed in mMRC, 6MWD, DE during deep breathing, and diaphragm thickness fraction (DTF). Of the participants, 33 patients (57%) were classified as responders, while 25 patients (43%) were considered non-responders. Baseline values of FEV1% predicted, 6MWD, DE during deep breathing, DTF, and PaO2 exhibited a significant elevation in responders as compared to non-responders. The changes of 6MWD were positively associated with the baseline values of DTF and DE during deep breathing, FEV1% predicted and PaO2, while negatively correlated with baseline value of mMRC. The predictive performance in terms of the area under the ROC curve for determining responder's DTF was found to be 0.769, accompanied by a sensitivity of 85% and specificity of 68%, using a cutoff value at 17.26%. Moreover, it was observed that DE during deep breathing could predict the area under the ROC curve for responders to be 0.753, with a sensitivity of 91% and specificity of 56% at a cutoff value of 3.61cm.

Conclusion

Diaphragm excursion serves as a valuable predictor for determining the enhancement of exercise tolerance following PR in patients with COPD-OSA overlap syndrome.

Trial Registration

ChiCTR1800020257, www.chictr.org.cn/index.aspx.

[Diaphragmatic ultrasonography for the pulmonologist: Technique and clinical use]

INTRODUCTION

Ultrasonography is an emerging tool that helps to assess diaphragmatic function. It is now widely used in ICUs to predict weaning from mechanical ventilation. Ultrasonography is readily available, harmless (no radiation), and repeatable with good interoperator reproducibility. Over the past few years, ultrasonography has seen increasing use in patients with chronic pulmonary pathologies.

STATE OF THE ART

The aim of this review is (1) to describe the ultrasound techniques used to assess diaphragmatic excursion and thickening, (2) to indicate the expected, normal values in healthy patients, and (3) to summarize the main findings and clinical applications in treatment of chronic respiratory disorders.

CONCLUSIONS

Chronic pulmonary diseases are associated with diaphragmatic dysfunction that can be assessed with ultrasound. Diaphragmatic dysfunction is primary in neuromuscular disorders and secondary to respiratory disease in other chronic pulmonary conditions (COPD, ILD). Ultrasound is correlated with the severity of the underlying disease (functional and clinical parameters).

PERSPECTIVES

The prognostic interest of diaphragm ultrasonography remains to be established, after which its utilization should become routine.

Clinical Utility of Chest Sonography in Chronic Obstructive Pulmonary Disease Patients Focusing on Diaphragmatic Measurements

BACKGROUND

There are many methods of evaluating diaphragmatic function, including trans-diaphragmatic pressure measurements, which are considered the key rule of diagnosis. We studied the clinical usefulness of chest ultrasonography in evaluating stable chronic obstructive pulmonary disease (COPD) patients and those in exacerbation, focusing on diaphragmatic measurements and their correlation with spirometry and other clinical parameters.

METHODS

In a prospective case-control study, we enrolled 100 COPD patients divided into 40 stable COPD patients and 60 patients with exacerbation. The analysis included 20 age-matched controls. In addition to the clinical assessment of the study population, radiological evaluation included chest radiographs and chest computed tomography. Transthoracic ultrasonography (TUS) was performed for all included subjects.

RESULTS

Multiple A lines (more than 3) were more frequent in COPD exacerbation than in stable patients, as was the case for B-lines. TUS significantly showed high specificity, negative predictive value, positive predictive value, and accuracy in detecting pleural effusion, consolidation, pneumothorax, and lung mass. Diaphragmatic measurements were significantly lower among stable COPD subjects than healthy controls. Diaphragmatic thickness and excursion displayed a significant negative correlation with body mass index and the dyspnea scale, and a positive correlation with spirometry measures. Patients in Global Initiative for Chronic Obstructive Lung Disease (GOLD) group D showed lower diaphragmatic measurements (thickness and excursion).

CONCLUSION

The TUS of COPD patients both in stable and exacerbated conditions and the assessment of diaphragm excursion and thickness by TUS in COPD patients and their correlations to disease-related factors proved informative and paved the way for the better management of COPD patients.

Efficacy of aerobic training and resistance training combined with external diaphragm pacing in patients with chronic obstructive pulmonary disease: A randomized controlled study

OBJECTIVE

To evaluate the efficacy of aerobic training, resistance training combined with external diaphragm pacing in patients with chronic obstructive pulmonary disease.

DESIGN

Randomized controlled trial.

SETTING

The Fourth Rehabilitation Hospital of Shanghai, China.

PARTICIPANTS

82 (67.0  ±  6.5 years, 59.8% male) patients with stable chronic obstructive pulmonary disease were randomized to intervention group 1 (n  =  27), intervention group 2 (n  =  28), and control group (n  =  27).

INTERVENTION

Intervention group 1 received aerobic and resistance training, while intervention group 2 received additional external diaphragm pacing. Control group received aerobic training only.

MAIN MEASURES

1-year follow-up of physical activity, body composition, respiratory function and diaphragm function.

RESULTS

Intervention groups 1 and 2 showed statistically improvements in the difference value compared with control group in terms of 6-min walk distance (-95.28  ±  20.09 and -101.92  ±  34.91 vs -63.58  ±  23.38), forced expiratory volume in 1 s (-0.042  ±  0.027 and -0.130  ±  0.050 vs -0.005  ±  0.068), fat-free mass (-2.11  ±  3.74 and -3.82  ±  3.74vs 0.28  ±  1.49) and chronic obstructive pulmonary disease assessment test value (2.16  ±  0.85 and 2.38  ±  1.02 vs 1.50  ±  0.93). Intervention group 2 showed significant difference in arterial oxygen pressure (-4.46  ±  3.22 vs -1.92  ±  3.45), diaphragm excursion during deep breaths (-0.82  ±  0.74 vs -0.38  ±  0.29), and diaphragm thickness fraction (-8.77  ±  3.22 vs -4.88  ±  2.69) compared with control group.

CONCLUSION

The combination of aerobic training, resistance training, and external diaphragm pacing obtained significant improvements in physical activity, respiratory function, body composition, arterial oxygen pressure, and diaphragm function in patients with chronic obstructive pulmonary disease.

TRIAL REGISTRATION

ChiCTR1800020257, www.chictr.org.cn/index.aspx.

Ultrasonographic evaluation of the diaphragm in critically ill patients to predict invasive mechanical ventilation

BACKGROUND

Diaphragm dysfunction is common in critically ill patients and associated with poorer outcomes. The function of the diaphragm can be evaluated at the bedside by measuring diaphragmatic excursion using ultrasonography. In this study, we investigated the ability of right-sided diaphragmatic excursion (RDE) to predict the need for invasive mechanical ventilation (IMV).

METHODS

Critically ill patients aged 18 years and older who presented to our emergency department between May 20, 2021 and May 19, 2022 and underwent measurement of RDE within 10 min of arrival were enrolled in this prospective study. The ability of RDE to predict the need for IMV was assessed by multivariable logistic regression and analysis of the area under the receiver-operating characteristic curve (AUROC).

RESULTS

A total of 314 patients were enrolled in the study; 113 (35.9%) of these patients required IMV. An increase of RDE value per each 0.1 cm was identified to be an independent predictor of IMV (adjusted odds ratio 0.08, 95% confidence interval [CI] 0.04-0.17, p < 0.001; AUROC 0.850, 95% CI 0.807-0.894). The RDE cutoff value was 1.2 cm (sensitivity 82.3%, 95% CI 74.0-88.8; specificity 78.1%, 95% CI 71.7-83.6). Time on a ventilator was significantly longer when the RDE was ≤ 1.2 cm (13 days [interquartile range 5, 27] versus 5 days [interquartile range 3, 8], p = 0.006).

CONCLUSIONS

In this study, RDE had a good ability to predict the need for IMV in critically ill patients. The optimal RDE cutoff value was 1.2 cm. Its benefit in patient management requires further investigation.

The effect of abdominal bracing on respiration during a lifting task: a cross-sectional study

BACKGROUND

Abdominal bracing is a maneuver widely used by rehabilitation specialists and sports trainers to improve spinal stability. This study aimed to investigate how lifting tasks with and without abdominal bracing affect the respiratory function of the diaphragm.

METHODS

M-mode ultrasonographic assessment of diaphragmatic motion combined with spirometry was performed on 31 healthy adults. Participants were asked to breathe continuously whilst lifting a load with spontaneous abdominal muscle contraction (natural loaded breathing) and abdominal bracing (AB loaded breathing).

RESULTS

Pearson's correlations revealed strong correlations between ultrasonography and spirometry measures (p < 0.001) for all types of breathing: tidal breathing (r = 0.709, r2 = 0.503), natural loaded breathing (r = 0.731, r2 = 0.534) and AB loaded breathing (r = 0.795, r2 = 0.632). Using paired-samples t-tests, the natural loaded breathing ultrasonography revealed more caudal diaphragm positions during inspiration (p < 0.001) but not during expiration (p = .101). Spirometry demonstrated lower lung volumes (L) at the end of inspiration and expiration (p < 0.001), with no changes in total lung volume (p = 0.06). The AB loaded breathing ultrasonography revealed more caudal diaphragm positions during inspiration (p = 0.002) but not during expiration (p = 0.05). Spirometry demonstrated lower lung volumes at the end of inspiration (p < 0.001), expiration (p = 0.002), and total lung volumes (p = 0.019).

CONCLUSION

This study demonstrated that abdominal bracing performed during a lifting task reduces lung volume despite an increase in diaphragmatic motion. Diaphragm excursions strongly correlate with lung volumes even under postural loading.

TRIAL REGISTRATION

The study was prospectively registered on 8 April 2021 at ClinicalTrials.gov with identification number NCT04841109.

Ultrasound assessment of the respiratory system using diaphragm motion-volume indices

Background

Although previous studies have determined limit values of normality for diaphragm excursion and thickening, it would be beneficial to determine the normal diaphragm motion-to-inspired volume ratio that integrates the activity of the diaphragm and the quality of the respiratory system.

Methods

To determine the normal values of selected ultrasound diaphragm motion-volume indices, subjects with normal pulmonary function testing were recruited. Ultrasound examination recorded diaphragm excursion on both sides during quiet breathing and deep inspiration. Diaphragm thickness was also measured. The inspired volumes of the corresponding cycles were systematically recorded using a spirometer. The indices were calculated using the ratio excursion, or percentage of thickening, divided by the corresponding breathing volume. From this corhort, normal values and limit values for normality were determined. These measurements were compared to those performed on the healthy side in patients with hemidiaphragm paralysis because an increase in hemidiaphragm activity has been previously demonstated in such circumstances.

Results

A total of 122 subjects (51 women, 71 men) with normal pulmonary function were included in the study. Statistical analysis revealed that the ratio of excursion, or percentage of thickening, to inspired volume ratio significantly differed between males and females. When the above-mentioned indices using excursion were normalized by body weight, no gender differences were found. The indices differed between normal respiratory function subjects and patients with hemidiaphragm paralysis (27 women, 41 men). On the paralyzed side, the average ratio of the excursion divided by the inspired volume was zero. On the healthy side, the indices using the excursion and the percentage of thickening during quiet breathing or deep inspiration were significantly increased comparedto patients with normal lung function. According to the logistic regression analysis, the most relevant indice appeared to be the ratio of the excursion measured during quiet breathing to the inspired volume.

Conclusion

The normal values of the diaphragm motion-volume indices could be useful to estimate the performance of the respiratory system. Proposed indices appear suitable in a context of hyperactivity.

Diaphragm dome height on chest radiography as a predictor of dynamic lung hyperinflation in COPD

Background and objective

Dynamic lung hyperinflation (DLH) can play a central role in exertional dyspnoea in patients with COPD. Chest radiography is the basic tool for assessing static lung hyperinflation in COPD. However, the predictive capacity of DLH using chest radiography remains unknown. This study was conducted to determine whether DLH can be predicted by measuring the height of the right diaphragm (dome height) on chest radiography.

Methods

This single-centre, retrospective cohort study included patients with stable COPD with pulmonary function test, cardiopulmonary exercise test, constant load test and pulmonary images. They were divided into two groups according to the median of changes of inspiratory capacity (ΔIC=IC lowest - IC at rest). The right diaphragm dome height and lung height were measured on plain chest radiography.

Results

Of the 48 patients included, 24 were classified as having higher DLH (ΔIC ≤-0.59 L from rest; -0.59 L, median of all) and 24 as having lower DLH. Dome height correlated with ΔIC (r=0.66, p<0.001). Multivariate analysis revealed that dome height was associated with higher DLH independent of % low attenuation area on chest computed tomography and forced expiratory volume in 1 s (FEV₁) % predicted. Furthermore, the area under the receiver operating characteristic curve of dome height to predict higher DLH was 0.86, with sensitivity and specificity of 83% and 75%, respectively, at a cut-off of 20.5 mm. Lung height was unrelated to ΔIC.

Conclusion

Diaphragm dome height on chest radiography may adequately predict higher DLH in patients with COPD.

Ultrasound assessment of diaphragmatic dynamics in patients with chronic obstructive pulmonary disease after treatment with indacaterol/glycopyrronium

INTRODUCTION

Air trapping is one of the main determinants of dyspnea in patients with chronic obstructive pulmonary disease (COPD). An increase in air trapping leads to a change in the normal diaphragmatic configuration with associated functional impairment. Said deterioration improves with bronchodilator therapy. Chest ultrasound (CU) has been used to assess changes in diaphragmatic motility after short-acting bronchodilator therapy, but there are no previous studies on these changes after long-acting bronchodilator treatment.

MATERIAL AND METHODS

Interventional prospective study. Patients with COPD and moderate to very severe ventilatory obstruction were included in the study. Diaphragm motion and thickness were assessed by CU before and after 3 months of treatment with indacaterol/glycopirronium 85/43 mcg.

RESULTS

Thirty patients were included (56.6% men, mean age: 69.4 ± 6.2 years). Pre- and post-treatment diaphragmatic mobility measured during resting breathing, deep breathing, and nasal sniffing were 19.9 ± 7.1 mm and 26.4 ± 8.7 mm (p < 0.0001); 42.5 ± 14.1 mm and 64.5 ± 25.9 mm (p < 0.0001); and 36.5 ± 17.4 mm and 46.7 ± 18.5 mm (p = 0.012), respectively. A significant improvement was also found in the minimum and maximum diaphragm thickness (p < 0.05), but there were no significant changes in the diaphragmatic shortening fraction after treatment (p = 0.341).

CONCLUSIONS

Treatment with indacaterol/glycopyrronium 85/43 mcg every 24 hours for 3 months improved diaphragmatic mobility in patients with COPD with moderate to very severe airway obstruction. CU may be useful for assessing the response to treatment in these patients.

The concept of detection of dynamic lung hyperinflation using cardiopulmonary exercise testing

Dynamic lung hyperinflation (DLH) caused by air trapping, which increases residual air volume, is a common cause of shortness of breath on exertion in chronic obstructive pulmonary disease (COPD). DLH is commonly evaluated by measuring the decrease in maximal inspiratory volume during exercise, or using the hyperventilation method. However, only few facilities perform these methods, and testing opportunities are limited. Therefore, we investigated the possibility of visually and qualitatively detecting DLH using data from a cardiopulmonary exercise test (CPET). Four men who underwent symptom-limiting CPET were included in this study, including a male patient in his 60s with confirmed COPD, a 50s male long-term smoker, and 2 healthy men in their 20s and 70s, respectively. We calculated the difference between the inspiratory tidal volume (TV I) and expiratory tidal volume (TV E) per breath (TV E-I) from the breath-by-breath data of each CPET and plotted it against the time axis. No decrease in TV E-I was observed in either of the healthy men. However, in the patient with COPD and long-term smoker, TV E-I began to decrease immediately after the initiation of exercise. These results indicate that DLH can be visually detected using CPET data. However, this study was a validation of a limited number of cases, and a comparison with existing evaluation methods and verification of disease specificity are required.

Relationship between respiratory muscles ultrasound parameters and running tests performance in adolescent football players. A pilot study

Purpose

Assessing the relationship between ultrasound imaging of respiratory muscles during tidal breathing and running tests (endurance and speed) in adolescent football players.

Methods

Ultrasound parameters of the diaphragm and intercostal muscles (shear modulus, thickness, excursion, and velocity), speed (30-m distance), and endurance parameters (multi-stage 20-m shuttle run test) were measured in 22 male adolescent football players. The relation between ultrasound and running tests were analysed by Spearman's correlation.

Results

Diaphragm shear modulus at the end of tidal inspiration was moderately negatively (R =  - 0.49; p = 0.2) correlated with the speed score at 10 m. The diaphragm and intercostal muscle shear modulus ratio was moderately to strongly negatively correlated with the speed score at 10 m and 30 m (about R =  - 0.48; p = 0.03). Diaphragm excursion was positively correlated with the speed score at 5 m (R = 0.46; p = 0.04) and 10 m (R = 0.52; p = 0.02). Diaphragm velocity was moderately positively correlated with the speed score at 5 m (R = 0.42; p = 0.06) and 30 m (R = 0.42; p = 0.07). Ultrasound parameters were not significantly related to all endurance parameters (R ≤ 0.36; p ≥ 0.11).

Conclusions

Ultrasound parameters of the respiratory muscles are related to speed score in adolescent football players. The current state of knowledge does not allow us to clearly define how important the respiratory muscles' ultrasound parameters can be in predicting some performance parameters in adolescent athletes.

MRI-assessed diaphragmatic function can predict frequent acute exacerbation of COPD: a prospective observational study based on telehealth-based monitoring system

BACKGROUND

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have considerably high mortality and re-hospitalisation rate. Diaphragmatic dysfunction (DD) is common in COPD patients. However, whether diaphragmatic dysfunction is related to acute exacerbation is yet to be elucidated. This study aimed to evaluate the diaphragm function by magnetic resonance imaging (MRI) in COPD patients and assess whether the impact of DD may help predict AECOPD.

METHODS

20 healthy adult volunteers and 80 COPD patients were enrolled. The diaphragms function parameters were accessed by MRI. Patients were guided to start self-management by the Telehealth-based monitoring system following the enrolment. Events of acute exacerbation of COPD were recorded by the system and confirmed by healthcare providers. Binary univariate and multivariate logistic regression analyses were performed to investigate the factors associated with the frequency of AECOPD. Receiver operating characteristic (ROC) curves were further used to assess the value of prediction indexes.

RESULTS

Fifty-nine COPD patients completed a one-year follow-up based on the Telehealth-based monitoring system. The clinical outcomes showed that the diaphragm function parameters at the end of maximal breathing were lower in the COPD group than in the healthy control group (P < 0.05). ANOVA showed significant differences among Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages for diaphragm function parameters, including chest wall motion, lung area, upper-lower diameter, and the diaphragm thickening fraction at the end of maximal breathing (P < 0.05). Moreover, significant differences in diaphragm function parameters were observed between patients with infrequent AECOPD (n = 28) and frequent AECOPD (n = 31) based on the frequency of AECOPD (P < 0.05). The diaphragm thickening fraction and the chest wall motion were associated with AECOPD after adjusting for age, sex, BMI, and lung functions, and the combination of predictions showed better accuracy in predicting the frequency of AECOPD.

CONCLUSIONS

In COPD patients, diaphragm function parameters correlate with the severity of airflow limitation. The diaphragm thickening fraction and the chest wall motion were associated with the frequency of AECOPD and can predict it.

Assessments and Targeted Rehabilitation Therapies for Diaphragmatic Dysfunction in Patients with Chronic Obstructive Pulmonary Disease: A Narrative Review

Purpose

This review summarizes the characteristics, assessment methods, and targeted rehabilitation therapies of diaphragm dysfunction in patients with chronic obstructive pulmonary disease (COPD).

Methods

Extensive literature was searched in PubMed, the Cochrane Library, Web of Science, Chinese National Knowledge Infrastructure Database, Wanfang, and SinoMed.

Results

Under the influence of oxidative stress, inflammation, and other factors, the diaphragm function of patients with COPD changes in mobility, muscle strength, thickness, and thickening. In patients with COPD, diaphragm mobility can be assessed using ultrasound, X-ray fluoroscopy, and magnetic resonance imaging. Diaphragmatic strength can be measured by transdiaphragmatic pressure and maximal inspiratory pressure. Diaphragmatic thickness and thickening can be assessed using ultrasound. Rehabilitation therapies targeting the diaphragm include diaphragmatic breathing, diaphragm-related manual therapy, and phrenic nerve electrical stimulation. Diaphragmatic breathing is safe, simple, and not limited by places. Diaphragmatic manual therapies, which require patient cooperation and one-on-one operation by a professional therapist, are effective. Phrenic nerve electrical stimulation is suitable for patients with severe conditions. These therapies improve the diaphragmatic function, lung function, dyspnea, and exercise capacity of patients with COPD.

Conclusion

The diaphragmatic function is commonly assessed in terms of mobility, strength, thickness, and thickening. Diaphragmatic targeted rehabilitation therapies have proven to be efficient, which are recommended to be included in the pulmonary rehabilitation strategy for patients with COPD.

Diaphragm Ultrasound in the Evaluation of Diaphragmatic Dysfunction in Lung Disease

The diaphragm is the most important respiratory muscle, and its function may be limited by acute and chronic diseases. A diaphragmatic ultrasound, which quantifies dysfunction through different approaches, is useful in evaluating work of breathing and diaphragm atrophy, predicting successful weaning, and diagnosing critically ill patients. This technique has been used to determine reduced diaphragmatic function in patients with chronic obstructive pulmonary disease and interstitial diseases, while in those with COVID-19, diaphragmatic ultrasound has been used to predict weaning failure from mechanical ventilation.

The Feasibility of Ultrasonographic Diaphragmatic Excursion in Healthy Dogs: Effect of Positioning, Diaphragmatic Location, and Body Weight of Dogs

Diaphragmatic excursion (DE) has been utilized for detecting respiratory related problems in humans. However, several factors should be considered such as the ultrasound technique and factors intrinsic to patients. Nevertheless, knowledge of the effect of these factors on DE in dogs is still lacking. The aim of this study was to evaluate the proper ultrasound technique by varying postures and diaphragmatic locations for DE measurement and to explore intrinsic factors such as diaphragmatic sides, sex, and body weight of dogs on DE. The prospective, analytic, cross-sectional study included 44 healthy dogs; 12 beagles and 32 dogs of other breeds. The experiment was divided into (i) an exploration of the proper ultrasound technique by varying postures (supine, standing, and recumbent in each of the right and left lateral positions), diaphragmatic locations (middle crus and proximal to the last rib), and diaphragmatic sublocations (xiphoid, mid, and proximal rib) for detection of DE and (ii) the evaluation of canine intrinsic factors affecting DE. The results show that the mid-diaphragmatic sublocation in the middle crus area in almost all positions revealed the highest percentage DE detection. However, DEs were revealed to be more accessible in the supine position. There was no significant difference in DE between the right and the left diaphragms or between the sexes of beagle dogs. However, body weight was significantly correlated with the DE among dogs of various sizes. In conclusion, the posture of the dogs and the diaphragmatic location can affect DE evaluation. Neither sex nor diaphragmatic side had an influence, but body weight was revealed as a major factor in DE in dogs.

Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease

BACKGROUND

In patients with chronic obstructive pulmonary disease (COPD), the maximum level of diaphragm excursion (DEmax) is correlated with dynamic lung hyperinflation and exercise tolerance. This study aimed to elucidate the utility of DEmax to predict the improvement in exercise tolerance after pulmonary rehabilitation (PR) in patients with COPD.

METHODS

This was a prospective cohort study. Of the 62 patients with stable COPD who participated in the outpatient PR programme from April 2018 to February 2021, 50 completed the programme. Six-minute walk distance (6MWD) was performed to evaluate exercise tolerance, and ultrasonography was performed to measure DEmax. Responders to PR in exercise capacity were defined as patients who demonstrated an increase of > 30 m in 6MWD. The receiver operating characteristic (ROC) curve was used to determine the cut-off point of DEmax to predict responses to PR.

RESULTS

Baseline levels of forced expiratory volume in 1 s, 6MWD, maximum inspiratory pressure, DEmax and quadriceps muscle strength were significantly higher, and peak dyspnoea of modified Borg (mBorg) scale score was lower in responders (n = 30) than in non-responders (n = 20) to PR (p < 0.01). In multivariate analysis, DEmax was significantly correlated with an increase of > 30 m in 6MWD. The area under the ROC curve of DEmax to predict responders was 0.915, with a sensitivity and specificity of 83% and 95%, respectively, at a cut-off value of 44.9 mm of DEmax.

CONCLUSION

DEmax could adequately predict the improvement in exercise tolerance after PR in patients with COPD.

Combined Use of Electrocardiography and Ultrasound to Detect Cardiac and Pulmonary Involvement after Recovery from COVID-19 Pneumonia: A Case Series

Background: Although severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) may cause an acute multiorgan syndrome (coronavirus disease 2019 (COVID-19)), data are emerging on mid- and long-term sequelae of COVID-19 pneumonia. Since no study has hitherto investigated the role of both cardiac and pulmonary ultrasound techniques in detecting such sequelae, this study aimed at evaluating these simple diagnostic tools to appraise the cardiopulmonary involvement after COVID-19 pneumonia. Methods: Twenty-nine patients fully recovered from COVID-19 pneumonia were considered at our centre. On admission, all patients underwent 12-lead electrocardiogram (ECG) and transthoracic echocardiography (TTE) evaluation. Compression ultrasound (CUS) and lung ultrasound (LUS) were also performed. Finally, in each patient, pathological findings detected on LUS were correlated with the pulmonary involvement occurring after COVID-19 pneumonia, as assessed on thoracic computed tomography (CT). Results: Out of 29 patients (mean age 70 ± 10 years; males 69%), prior cardiovascular and pulmonary comorbidities were recorded in 22 (76%). Twenty-seven patients (93%) were in sinus rhythm and two (7%) in atrial fibrillation. Persistence of ECG abnormalities from the acute phase was common, and nonspecific repolarisation abnormalities (93%) reflected the high prevalence of pericardial involvement on TTE (86%). Likewise, pleural abnormalities were frequently observed (66%). TTE signs of left and right ventricular dysfunction were reported in two patients, and values of systolic pulmonary artery pressure were abnormal in 16 (55%, despite the absence of prior comorbidities in 44% of them). Regarding LUS evaluation, most patients displayed abnormal values of diaphragmatic thickness and excursion (93%), which correlated well with the high prevalence (76%) of pathological findings on CT scan. CUS ruled out deep vein thrombosis in all patients. Conclusions: Data on cardiopulmonary involvement after COVID-19 pneumonia are scarce. In our study, simple diagnostic tools (TTE and LUS) proved clinically useful for the detection of cardiopulmonary complications after COVID-19 pneumonia.

The effect of erector spinae block versus serratus plane block on pain scores and diaphragmatic excursion in multiple rib fractures. A prospective randomized trial

OBJECTIVES

We aimed to investigate whether ultrasound guided erector spinae plane block and serratus anterior plane block would provide effective and safe analgesia in patients with fracture ribs, and to detect their effects on diaphragmatic excursion in such cases.

DESIGN

Prospective double-blind randomized study.

SETTINGS

Tanta University Hospitals.

SUBJECT

Fifty adult patients ASA I, II with fracture ribs.

METHODS

Patients were randomized to receive either ultrasound guided erector spinae block (Group I) or serratus plane block (Group II) with injection of 19 ml bupivacaine 0.25% plus 1 ml dexamethasone (4 mg). Pain scores, 24 hour total analgesic requirements, diaphragmatic excursion and incidence of adverse events were recorded.

RESULTS

At rest and dynamic pain scores were significantly lower in Group I as compared to Group II from 2 hour up to 24 hour post block [median differences (95% CI): -1(-0.9999;0.0002), -1(-0.9999;0.0002), -1(-0.9998;0.0003), -1(-1.000;-0.000) and -1(-2.0000;-1.0000), -1(-0.9998;-0.0001), -1(-1.0001;-1.0002), -1(-2.000;0.000) respectively], with a significant reduction in 24h opioid consumption in Group I in comparison to Group II (P= 0.004*). Diaphragmatic excursion showed a significant improvement in Group I when compared to Group II at 2, 6, 12, and 24 hour after the block (p = 0.024*, 0.038*, 0.027*, 0.042* correspondingly). No adverse events were noted.

CONCLUSIONS

Both erector spinae block and serratus plane block provided safe and effective pain relief in traumatic rib fractures. Though the erector spinae group displayed significantly reduced pain scores, decreased analgesic needs and improved diaphragmatic excursion as compared to serratus group, nevertheless, this was of no clinical significance.