Assessment of diaphragmatic function by ultrasonography: Current approach and perspectives

Ultrasound-guided diaphragm evaluation and outcomes in severe acute exacerbation of chronic obstructive pulmonary disease (uDISCO Study): an observational study

Acute exacerbations of chronic obstructive pulmonary disease (COPD) are associated with compromised diaphragmatic function. This can be evaluated using point-of-care ultrasound. The association of diaphragm function with hospital length of stay or mortality has not been assessed earlier. This study aimed to evaluate the correlation of diaphragmatic function with length of hospital stay, mortality, and non-invasive ventilation (NIV) failure in severe acute exacerbation of COPD. Diaphragmatic excursion and thickening index (Tdi) were evaluated with ultrasound-guided assessment in individuals with severe acute exacerbation of COPD at the time of hospitalization. The individuals were evaluated for length of stay in survivors, NIV ventilation failure in those requiring NIV therapy, and mortality in non-survivors. A total of 110 individuals were screened, and 60 of these were enrolled. A total of 55 individuals survived, and 5 died. The length of stay had a negative correlation with excursion (R: -0.78, p<0.001) and Tdi (R: -0.96, p<0.001). The excursion and Tdi were smaller by 30% and 50%, respectively, in the event of NIV failure compared to NIV success. Excursion ≤1.96 cm [area under receiver-operating characteristic curve (AUROC): 0.958] or Tdi≤92% (AUROC: 0.974) were associated with length of stay ≥8 days. Excursion ≤1.48 cm (AUROC: 0.75) or Tdi≤51.2% (AUROC: 0.8) were associated with NIV failure. Tdi≤40% was associated with a high risk of mortality (RR: 22.67, p=0.035). Smaller diaphragmatic excursion, or Tdi, correlated with prolonged LoS, mortality, and NIV failure.

Breathless Strength: Ultrasonographic Insights into Expiratory Muscle Dysfunction in Spinal Cord Injury

Background and Objectives: This study aimed to evaluate the predictive value of ultrasonographic abdominal muscle thickness and thickening ratios for expiratory muscle strength in SCI patients. Materials and Methods: A case-controlled, cross-sectional study was conducted with 36 SCI patients and 30 age- and sex-matched healthy controls. Ultrasonographic measurements of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) were performed at rest and during forced expiration. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured to assess respiratory muscle strength. Correlation and regression analyses were performed to determine the relationship between ultrasonography (USG) parameters and expiratory muscle function. Results: SCI patients exhibited significantly lower MIP (76.27 ± 29 cmH2O vs. 91.63 ± 17.3 cmH2O, p = 0.007) and MEP (64.52 ± 21.55 cmH2O vs. 119.1 ± 26.48 cmH2O, p < 0.001) compared to healthy individuals. Ultrasonographic measurements revealed a significant reduction in forced thickness and thickening ratios of EO, IO, and TrA muscles in SCI patients (p < 0.001). MEP was positively correlated with EO forced thickness (r = 0.333, p = 0.047), IO forced thickness (r = 0.501, p = 0.002), and TrA forced thickness (r = 0.530, p = 0.001). Multiple linear regression analysis identified TrA forced thickness as the strongest predictor of MEP (β = 0.49, p = 0.001). Conclusions: Ultrasonographic measurements of abdominal muscle thickness and thickening ratios provide valuable insights into expiratory muscle dysfunction in SCI patients. TrA forced thickness demonstrated the strongest association with MEP, suggesting its potential as a novel, non-invasive biomarker for expiratory muscle weakness. These results support the use of USG as a practical clinical tool for guiding respiratory assessment and rehabilitation strategies in patients with spinal cord injury.

Effect of pelvic floor muscle combined with pulmonary rehabilitation training on lung function in elderly patients after surgery for intertrochanteric fractures of the femur: a randomized controlled trial

OBJECTIVE

To explore the effects of pelvic floor muscle (PFM) combined with pulmonary rehabilitation training on diaphragm function and lung function in elderly patients with intertrochanteric fracture.

METHODS

This study was conducted by a randomized controlled single-blind method, 50 elderly patients with intertrochanteric fracture in Beijing Xiaotangshan Hospital were selected and divided into the combined training group (Experimental group, n = 25) and the lung function training group (Control group, n = 25) by the random number table method. Patients in the combined training group received pelvic floor muscle training combined with lung rehabilitation training, and patients in the lung function training group received lung rehabilitation training. Forced vital capacity (FVC), forced expiratory volume in the first second/FVC (FEV1/FVC) and peak expiratory flow (PEF) were evaluated before and after intervention to analyze the improvement of lung function. Diaphragm thickening fraction (DTF) and diaphragm excursion (DE) were used to observe the improvement of diaphragm function.

RESULTS

After 4 weeks of intervention, there were significant differences in lung function and diaphragm function between the two groups compared with the improvement before the intervention, but patients in the combined training group had more significant improvements in FVC, FEV1/FVC, PEF, DTF, and DE.

CONCLUSION

Pelvic floor muscle combined with lung function training can improve the diaphragm function more significantly in elderly patients with intertrochanteric fracture after operation, and thus affect the lung function of patients.

Ultrasound examiners' ability to describe ovarian cancer spread using preacquired ultrasound videoclips from a selected patient sample with high prevalence of cancer spread

OBJECTIVES

To assess the ability, as well as factors affecting the ability, of ultrasound examiners with different levels of ultrasound experience to detect correctly infiltration of ovarian cancer in predefined anatomical locations, and to evaluate the inter-rater agreement regarding the presence or absence of cancer infiltration, using preacquired ultrasound videoclips obtained in a selected patient sample with a high prevalence of cancer spread.

METHODS

This study forms part of the Imaging Study in Advanced ovArian Cancer multicenter observational study (NCT03808792). Ultrasound videoclips showing assessment of infiltration of ovarian cancer were obtained by the principal investigator (an ultrasound expert, who did not participate in rating) at 19 predefined anatomical sites in the abdomen and pelvis, including five sites that, if infiltrated, would indicate tumor non-resectability. For each site, there were 10 videoclips showing cancer infiltration and 10 showing no cancer infiltration. The reference standard was either findings at surgery with histological confirmation or response to chemotherapy. For statistical analysis, the 19 sites were grouped into four anatomical regions: pelvis, middle abdomen, upper abdomen and lymph nodes. The videoclips were assessed by raters comprising both senior gynecologists (mainly self-trained expert ultrasound examiners who perform preoperative ultrasound assessment of ovarian cancer spread almost daily) and gynecologists who had undergone a minimum of 6 months' supervised training in the preoperative ultrasound assessment of ovarian cancer spread in a gynecological oncology center. The raters were classified as highly experienced or less experienced based on annual individual caseload and the number of years that they had been performing ultrasound evaluation of ovarian cancer spread. Raters were aware that for each site there would be 10 videoclips with and 10 without cancer infiltration. Each rater independently classified every videoclip as showing or not showing cancer infiltration and rated the image quality (on a scale from 0 to 10) and their diagnostic confidence (on a scale from 0 to 10). A generalized linear mixed model with random effects was used to estimate which factors (including level of experience, image quality, diagnostic confidence and anatomical region) affected the likelihood of a correct classification of cancer infiltration. We assessed the observed percentage of videoclips classified correctly, the expected percentage of videoclips classified correctly based on the generalized linear mixed model and inter-rater agreement (reliability) in classifying anatomical sites as being infiltrated by cancer.

RESULTS

Twenty-five raters participated in the study, of whom 13 were highly experienced and 12 were less experienced. The observed percentage of correct classification of cancer infiltration ranged from 70% to 100% depending on rater and anatomical site, and the median percentage of correct classification for the 25 raters ranged from 90% to 100%. The probability of correct classification of all 380 videoclips ranged from 0.956 to 0.975 and was not affected by the rater's level of ultrasound experience. The likelihood of correct classification increased with increased image quality and diagnostic confidence and was affected by anatomical region. It was highest for sites in the pelvis, second highest for those in the middle abdomen, third highest for lymph nodes and lowest for sites in the upper abdomen. The inter-rater agreement of all 25 raters regarding the presence of cancer infiltration ranged from substantial (Fleiss kappa, 0.68 (95% CI, 0.66-0.71)) to very good (Fleiss kappa, 0.99 (95% CI, 0.97-1.00)) depending on the anatomical site. It was lowest for sites in the upper abdomen (Fleiss kappa, 0.68 (95% CI, 0.66-0.71) to 0.97 (95% CI, 0.94-0.99)) and highest for sites in the pelvis (Fleiss kappa, 0.94 (95% CI, 0.92-0.97) to 0.99 (95% CI, 0.97-1.00)).

CONCLUSIONS

Ultrasound examiners with different levels of ultrasound experience can classify correctly predefined anatomical sites as being infiltrated or not infiltrated by ovarian cancer based on video recordings obtained by an experienced ultrasound examiner, and the inter-rater agreement is substantial. The likelihood of correct classification as well as the inter-rater agreement is highest for sites in the pelvis and lowest for sites in the upper abdomen. However, owing to the study design, our results regarding diagnostic accuracy and inter-rater agreement are likely to be overoptimistic. © 2025 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Diaphragmatic ultrasound: approach, emerging evidence, and future perspectives in non-ICU patients

Diaphragmatic dysfunction is an important contributor to hypercapnic respiratory failure, but its presence is often challenging to determine at the bedside. Diaphragm ultrasound provides an opportunity to evaluate the function of the diaphragm noninvasively by evaluating the following parameters that can help define diaphragmatic dysfunction: diaphragm excursion, diaphragm muscle thickness, and thickening fraction. Its evaluation has the potential to assist with diagnosis of respiratory failure, provide prognosis, and assist with patient monitoring and should be considered as part of an internal medicine physician's and emergency physician's skill set. This article provides an overview on how to perform diaphragm ultrasound, review its pitfalls, and discuss the evidence of its use in patients with neuromuscular disorders and chronic obstructive pulmonary disease. Finally, its potential emerging uses in the perioperative setting and for evaluation of acute heart failure are discussed.

Diaphragm function in patients with asthma and healthy controls: A cross-sectional study

BACKGROUND

Asthma is a chronic respiratory disease characterized by airway inflammation and variable respiratory symptoms. While peripheral muscle deconditioning is known to affect lung function and exercise tolerance, the role of respiratory muscle dysfunction, particularly the diaphragm, remains underexplored.

OBJECTIVE

We aim to evaluate potential differences in diaphragm function in patients with asthma.

METHODS

We conducted a prospective, observational study comparing diaphragmatic function of 50 patients with asthma and 50 healthy controls. Two independent operators evaluated diaphragm contraction using tidal breathing thickening fraction (TF). Diaphragm dysfunction was defined as a TF < 20 %. Additional assessments included flow-volume spirometry, impulse oscillometry (IOS), FeNO, blood eosinophil count, and the Sniff Inspiratory Nasal Pressure (SNIP) test.

RESULTS

Patients with asthma demonstrated significantly reduced diaphragm TF compared to healthy controls (p < 0.0001). Diaphragm dysfunction was significantly more prevalent in asthmatic patients (p < 0.0001), affecting 62%-66 % of the right hemidiaphragm and 46%-54 % of the left. Reduced TF was associated with longer disease duration (p = 0.03) and higher exacerbation rates (p = 0.04). No significant correlations were observed between TF and anthropometric data, asthma treatments, lung function, or Th2 biomarkers. SNIP measurements did not correlate with diaphragm TF. The limited sample size and the cross-sectional design were the main limitations of the study.

CONCLUSION

Diaphragm dysfunction is prevalent in asthma and associated with disease severity, including exacerbation frequency and longer disease duration. Impaired diaphragm function may contribute to persistent symptoms and exercise intolerance, representing a novel treatable trait in asthma management.

Unraveling Ventilator-Induced Diaphragmatic Dysfunction: A Comprehensive Narrative Review on Pathogenesis, Diagnosis and Management of Ventilator-Induced Diaphragmatic Dysfunction

INTRODUCTION

Mechanical ventilation (MV) is a crucial intervention for patients with respiratory failure to ensure optimal gas exchange. However, there is strong evidence that MV exerts significant structural and functional alterations on the diaphragm, leading to a notable decline in its contractile force and the consequent atrophy of its muscle fibers. This condition, referred to as ventilator-induced diaphragmatic dysfunction (VIDD), is an integral factor contributing to challenges in weaning patients off MV, a reduction in their quality of life, and escalated Mortality Risks.

OBJECTIVES

This review highlights the complications of MV, with a focus on VIDD and its clinical implications. It explores bedside diagnostic tools for VIDD and examines exercise-based interventions aimed at preventing or reversing daiphragmatic weakness.

DISCUSSION

Rehabilitation programs, including early mobilization and inspiratory muscle training (IMT) for critically ill patients, have the potential to prevent or mitigate the adverse effects of prolonged Mechanical ventilator and improve clinical outcomes. Numerous studies have demonstrated that these interventions are both safe and feasible, offering benefits such as enhanced physical functioning, reduced duration of mechanical ventilation, and shorter stays in intensive care and hospital settings. However, despite these demonstrated advantages, the implementation of rehabilitation programs remains infrequent in routine clinical practice, often hindered by various perceived barriers.

CONCLUSION

Recognizing and addressing respiratory muscle weakness is crucial, as it represents a reversible and treatable factor that can significantly improve patient outcomes.

Multimodal diaphragmatic ultrasound indicators in healthy adults: reliability and consistency observation by ultrasound physician and critical care physician

Background

This study aimed to establish normal reference values for multimodal diaphragmatic ultrasound indices in healthy adult volunteers and evaluate intra-and inter-observer consistency between ultrasound physicians and critical care physicians.

Methods

An ultrasound physician (US physician) used techniques such as B-mode, M-mode, Tissue Doppler Imaging (TDI), and shear wave elastography (SWE) to measure diaphragmatic parameters in 46 healthy adults during quiet and deep breathing. A critical care physician (CC physician) trained in diaphragmatic ultrasound repeated these measurements. Consistency was analyzed in intra-researcher and inter-researchers of various diaphragmatic ultrasound indicators.

Results

Diaphragm thickness at the end of expiration, end of inspiration, and end of deep inspiration (DT-ee, DT-ei, and DT-edi) in both B-mode and M-mode method of males were higher than that of females, Diaphragm shear modulus-edi of males is higher than that of females (P<0.05). Between different diaphragmatic ultrasound indicators, the study showed a moderate consistency of peak contraction velocity (PCV) and peak relaxation velocity (PRV) in intra-researcher of CC physician and inter-researchers between US physician and CC physician, (ICC = 0.678 and 0.704, P < 0.001). For other multiple diaphragm ultrasound indicators, our study showed an excellent consistency in both intra-researcher and inter-researchers (ICC = 0.824-0.994, P < 0.001). For DT measurement by B-mode and M-mode, it showed an excellent consistency in both intra-researcher, intra-researcher of US physician, intra-researcher of CC physician and total cases (ICC = 0.919-0.960, P < 0.001). Correlation analysis showed a moderate positive correlation between diaphragm displacement during quiet breathing (DD-qb) and pleural sliding displacement (PSD) in US physician (r = 0.568), CC physician (r = 0.470), and total cases (r = 0.511), with significant differences (P < 0.05).

Conclusion

Ultrasound-based assessment of diaphragmatic function is a reliable method. This study provides normal reference values and highlights the high observer reproducibility among experienced ultrasound and critical care physicians.

Diaphragm Ultrasonography in Patients Without Symptoms or Signs of Respiratory Impairment

INTRODUCTION/AIMS

We aimed to determine differences in diaphragm thickness by including/excluding pleural and peritoneal membranes, the variability in diaphragm thickness over the apposition zone, and the predictors of diaphragm thickness and excursion measurements.

METHODS

At least 10 male and female subjects were recruited for each decade of life. Spirometry, respiratory muscle strength, and the diaphragm ultrasound (US) measurements were performed. Multivariate linear regression was applied to determine associations between diaphragm US parameters, subject characteristics, spirometry, and respiratory muscle strength.

RESULTS

In 156 subjects (mean 47.8 ± 17.7; 20-80 years of age), a significant difference in diaphragm thickness was found when comparing measurements that included and excluded the pleural and peritoneal membranes (mean 2.3 vs. 1.7 mm; average difference of 35% (95% CI [15.3-60]); p < 0.001), as well as the minimum and maximum diaphragm thicknesses at different locations over the apposition zone (mean 1.4 vs. 2.1 mm; p < 0.001). Adjusting for sex, age, height, sniff nasal inspiratory pressure, and forced vital capacity, a positive association was found between body mass index (BMI) and diaphragm thickness (β =0.024, p < 0.001, partial R 2 = 0.31, 95% CI [0.018, 0.030]); a negative association was found with the thickening ratio (β = -0.013, p = 0.050, partial R 2 = 0.04, 95% CI [-0.024, -0.002]).

DISCUSSION

Caliper placement and the location of measurement over the apposition zone greatly affect diaphragm thickness, which is also associated with BMI. Therefore, a standardized protocol for measuring diaphragmatic thickness and excursion is desirable, and BMI should be considered when interpreting the results.

Diaphragm excursion difference as an adjunct predictor marker of postoperative pulmonary complications in video-assisted thoracoscopic surgery: a prospective, observational study

Background

Video-assisted thoracoscopic surgery (VATS) often leads to a significant number of postoperative pulmonary complications (PPCs). The diaphragm is the primary muscle involved in respiration. Diaphragm ultrasound is increasingly used as a noninvasive and portable tool for evaluating diaphragmatic contractile function. The diaphragm excursion difference (DED) provides a valuable predictive measure for clinical outcomes. This prospective, observational study aimed to evaluate the predictive feasibility of DED in relation to PPCs in patients undergoing VATS.

Methods

Between March and August 2023, a total of 151 patients undergoing VATS were enrolled in the study. Each patient underwent diaphragm ultrasound examinations both before anesthesia and within one hour after extubation. During these examinations, diaphragm excursion (DE) was recorded during quiet breathing (QB) and deep breathing (DB). The DED and diaphragm excursion fraction (DEF) were calculated at these two time points. The primary outcome measured was the incidence of major pulmonary complications occurring within seven days after surgery, while secondary outcomes included the rate of diaphragm dysfunction, duration of hospitalization, oxygenation status, and pain scores on the first and second postoperative days.

Results

Data from 151 patients were analyzed, revealing that 32 patients (21%) developed PPCs. Patients who developed PPCs exhibited a significantly lower postoperative diaphragm excursion during DB (2.27±0.59 vs. 3.31±0.99, P<0.001). They also showed a lower postoperative DED (0.94±0.44 vs. 1.94±0.91, P<0.001) and a higher DEF (0.59±0.13 vs. 0.44±0.12, P<0.001) compared to those without PPCs. In receiver operating characteristic curve analysis, the postoperative DED demonstrated a high sensitivity of 90.6% and a lower specificity of 64.7% for predicting PPCs, with an area under the curve (AUC) of 0.860 and a 95% confidence interval (CI) ranging from 0.788 to 0.926.

Conclusions

After VATS, lower postoperative DED may serve as an additional marker. This can help predict the risk of pulmonary complications.

Evaluating Diaphragmatic Paralysis After Pediatric Cardiac Surgery and the Role of Plication in Outcome Improvement: Insights From a Single-Center Experience

INTRODUCTION

Diaphragmatic paralysis (DP) is a significant complication following cardiac surgery, particularly impacting neonates and infants. This retrospective study aims to evaluate the incidence of DP, identify risk factors, and assess the impact of diaphragmatic plication as a definitive management strategy.

METHODS

We analyzed the clinical records of pediatric patients who underwent cardiac surgery at our center from 2016 to 2023. Cases of DP were identified, potential risk factors examined, and the effectiveness of plication assessed. Patients were categorized into early and late groups based on the timing of DP diagnosis relative to surgery.

RESULTS

Out of 2,331 pediatric cardiac surgery patients (median age 7.2 months), DP was identified in 60 patients (2.6%), with a higher incidence of left-sided paralysis in 37 patients (61.7%). Diaphragmatic paralysis was more frequently associated with specific procedures, such as bidirectional Glenn, arterial switch operations, and Blalock-Taussig-Thomas shunt. Patients with DP had significantly longer intensive care unit (ICU) stays (21 vs 4 days, P < .001) and total hospital stays (38 vs 11 days, P < .001). Following plication, median mechanical ventilation (MV) hours significantly decreased (73-13 h, P < .001), and ICU stays were reduced (15-3 days, P < .001). Early plication was associated with shorter MV time and hospital stays.

CONCLUSION

Diaphragmatic paralysis is a notable complication after cardiac surgery. Diaphragmatic plication proves to be an effective intervention, reducing MV duration and hospital stays. These findings underscore the importance of early recognition and intervention for improved postoperative outcomes.

The Perception of the Diaphragm with Ultrasound: Always There Yet Overlooked?

Diaphragm ultrasound makes it possible to diagnose diaphragmatic atrophy and dysfunction. Important indications include unclear dyspnea; diaphragmatic elevation; assessment of diaphragm dysfunction in pulmonary, neuromuscular and neurovascular diseases; and in critically ill patients before noninvasive and mechanical ventilation and follow-up of diaphragm thickness and function during mechanical ventilation with potential prediction of prolonged weaning. In patients with respiratory insufficiency and potential diaphragm dysfunction, it is possible to objectify the contribution of diaphragm dysfunction. In addition, assessment of diaphragmatic hernias, tumors and diaphragmatic dysfunction in COVID-19 and diaphragmatic ultrasound in sports medicine have been described. This narrative review includes the sonomorphology of the diaphragm, standardization of ultrasonographic investigation with transducer positions and ultrasound techniques, normal findings and diagnostic criteria for pathological findings. The correct sonographic measurement, calculation and evaluation can ultimately influence further therapeutic procedures for the patient suffering from diaphragm dysfunction in various diseases.

Relationship Between Diaphragm Function and Sarcopenia Assessed by Ultrasound: A Cross-Sectional Study

Background/Objectives: The diaphragm is important for respiration, but the effects of age-related muscle loss and sarcopenia on diaphragm function are unclear. We evaluated the associations of sarcopenia and skeletal muscle mass (SMM) with diaphragm function. Methods: This study was conducted at three Japanese hospitals from May 2023 to September 2024. The participants underwent bioelectrical impedance for SMM assessment, as well as pulmonary function tests. Diaphragm ultrasound was used to measure the thickness at functional residual capacity (FRC), thickening fraction (TF), and diaphragm excursion (DE) during deep breathing (DB), and their associations with sarcopenia and low skeletal muscle index (SMI) were analyzed. Results: Overall, 148 patients (mean age 78.1 years; sarcopenia, n = 35; non-sarcopenia, n = 103) were included. No statistically significant differences in thickness(FRC), TF and DE were observed between the sarcopenia group and the non-sarcopenia group. The low SMI group had significantly lower thickness (difference -0.22, 95% CI; -0.41, -0.29) and DE (difference -9.2, 95%CI; -14.0, -4.49) than the normal SMI group. Multivariable linear regression analyses adjusted for age, sex, and stature revealed no association between thickness (FRC) and sarcopenia (p = 0.98), but thickness (FRC) was negatively associated with low SMI (p = 0.034). DE during DB was negatively associated with sarcopenia (p = 0.024) and low SMI (p = 0.001). TF showed no associations. Conclusions: DE during DB was reduced in patients with sarcopenia and low SMI, and thickness (FRC) was reduced in those with low SMI without sarcopenia.

Advancing Lung Ultrasound: The Development and Application of the Anatomical M-Mode Evaluation for Lung Swings (AMLES) Technique in Respiratory Assessment

Exploring the frontiers of lung ultrasound, this document details a groundbreaking technique for lung function evaluation using anatomical M-mode, also known as angle-independent M-mode. The method, termed AMLES (Anatomical M-Mode Evaluation for Lung Swings), quantifies the displacement of the lung curtain observed at the bilateral costophrenic recesses. This approach translates lung curtain movements into graphical data, offering insights into respiratory mechanics and enhancing the assessment of lung ventilation in emergency settings.

Inspiration Time: The Ultrasound Variable Necessary to Study the Diaphragm Functionality. A Cross-Sectional Controlled Study

Introduction

The diaphragm is considered the main inspiratory muscle, and as such, its assessment is crucial in patients with respiratory pathology. It is known that the contractile capacity of a muscle is determined by strength, length, and the duration of contraction. Although transdiaphragmatic pressure is the gold standard test for its study, ultrasound has been confirmed as a useful tool in clinical practice. Thanks to it, both the strength (diaphragmatic thickness) and the length of movement (diaphragmatic excursion) can be evaluated. This study aims to investigate the relationship between the inspiratory time and the diaphragmatic contraction.

Design

Cross-sectional controlled study.

Methodology

Eighty healthy subjects, yoga practitioners, with no previous respiratory pathology participated in this study. They were asked to take three different types of deep breaths: diaphragmatic with nasal inspiration, pursed-lip inspiration, and ujjayi (nasal inspiration with slight contraction of the glottis). The variables of thickness, excursion, and inspiratory contraction time were taken for each of them by ultrasound.

Results

Diaphragmatic contraction time is the only variable that shows a significant correlation with the other two. Thus, the correlation between inspiratory time and diaphragmatic thickness is significant (p < .001) for the three breaths: diaphragmatic (0.60), ujjayi (0.67), and pursed lips (0.39) and the correlation between inspiratory time and diaphragmatic excursion is significant for diaphragmatic breaths (-0.24, p = .035) and ujjayi (0.27, p = .017), but not in pursed lips (-0.01, p = .90).

Conclusion

The inspiratory contraction time and the diaphragmatic excursion are two essential variables in the dynamic functional evaluation of the diaphragm, compared to the diaphragmatic thickness measurement that only reports its strength.

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.

Decreased diaphragm moving distance measured by ultrasound speckle tracking reflects poor prognosis in amyotrophic lateral sclerosis

Objective

Decreased cephalocaudal diaphragm movement may indicate respiratory dysfunction in amyotrophic lateral sclerosis (ALS). We aimed to evaluate diaphragm function in ALS using ultrasound speckle tracking, an image-analysis technology that follows similar pixel patterns.

Methods

We developed an offline application that tracks pixel patterns of recorded ultrasound video images using speckle-tracking methods. Ultrasonography of the diaphragm movement during spontaneous quiet respiration was performed on 19 ALS patients and 21 controls to measure the diaphragm moving distance (DMD) in the cephalocaudal direction during a single respiration. We compared respiratory function measures and analyzed the relationship between the clinical profiles and DMD.

Results

DMD was significantly lower in ALS patients than in the control group (0.6 ± 1.4 mm vs 2.2 ± 2.2 mm, p < 0.01) and positively correlated with phrenic nerve compound motor action potential amplitude (R = 0.63, p = 0.01). DMD was negatively correlated with the change in the ALS Functional Rating Scale-Revised scores per month after the exam (R = -0.61, p = 0.02), and those with a larger rate of decline had a significantly lower DMD (p = 0.03).

Conclusions

Diaphragm ultrasound speckle tracking enabled the detection of diaphragm dysfunction in ALS.

Significance

Diaphragm ultrasound speckle tracking may be useful for predicting prognosis.

The role of extradiaphragmatic muscles' ultrasound on the diagnosis and follow-up of diaphragmatic dysfunction associated with cervical septic arthritis: A case report and literature review

Cervical septic arthritis can lead to complications such as epidural abscess, which may result in respiratory failure. We present a case of a 78-year-old male with cervical septic arthritis complicated by epidural abscess, leading to severe diaphragm dysfunction. Ultrasound evaluation revealed dysfunction of the left hemidiaphragm and compensatory activation of accessory respiratory muscles. Treatment included antibiotic therapy and corticosteroids, alongside respiratory support. After 21 days, improvements were observed in diaphragmatic function and respiratory muscle activation. Our findings highlight the importance of assessing both diaphragm and accessory respiratory muscles in cases of cervical septic arthritis with respiratory complications.

Efficacy of ultrasonographic diaphragmatic parameters in distinguishing diaphragmatic dysfunction in cats

OBJECTIVES

Diaphragmatic dysfunction (DD) is often underdiagnosed in veterinary medicine. Various ultrasonographic diaphragmatic parameters, including diaphragmatic excursion (DE), diaphragmatic thickness (Tdi) and diaphragmatic thickening fraction (DTF), can be used to identify DD. We aimed to establish normal reference intervals in healthy cats, examine the effects of intrinsic factors on diaphragmatic parameters and evaluate the efficacy of these parameters in identifying DD in healthy and diseased cats.

METHODS

This prospective observational study was conducted on 22 healthy cats and 12 diseased cats using ultrasonographic techniques to evaluate DE, Tdi and DTF. The correlation between diaphragmatic parameters and intrinsic factors, including sex, age, body weight and body condition score, was analysed using Pearson correlation analysis. Cut-off values for healthy and diseased cats were established using receiver operating characteristic curve analysis.

RESULTS

The mean DEs of the left and right hemidiaphragms were 0.66 ± 0.16 and 0.64 ± 0.18 cm, respectively. The mean Tdis in the end-inspiration phase were 0.13 ± 0.03 and 0.12 ± 0.03 cm for the left and right hemidiaphragms, respectively, whereas in the end-expiration phase the mean Tdi was 0.07 ± 0.03 cm for both hemidiaphragms. The DTF ranges for the left and right hemidiaphragms were 23.90-122.1% and 38.80-107%, respectively. Intrinsic factors had no significant impact on DE, Tdi and DTF. The DE measurements for the left hemidiaphragm were more accurate for evaluating diaphragmatic function. To distinguish between healthy and diseased cats, the cut-off value, sensitivity and specificity were 0.458 cm (area under the curve [AUC] 0.846), 75.00% and 86.36%, respectively, for the left hemidiaphragm and 0.423 cm (AUC 0.704), 41.67% and 100%, respectively, for the right hemidiaphragm.

CONCLUSIONS AND RELEVANCE

Normal reference values for DE, Tdi and DTF were established for healthy cats. DE, particularly in the left hemidiaphragm, obtained using routine ultrasonography, improves the efficacy of identifying DD and assists clinicians in the diagnosis and treatment of cats with cardiorespiratory disease.

Diaphragm Muscle Atrophy Contributes to Low Physical Capacity in COVID-19 Survivors

Fatigue and dyspnea are the most commonly reported long-term complaints in individuals previously infected with SARS-CoV-2. This study aimed to comprehensively evaluate diaphragm muscle function in post-COVID-19 patients and investigate whether potential diaphragm dysfunction contributes to physical functioning impairment. A total of 46 patients who qualified for pulmonary rehabilitation were examined. Diaphragm muscle function parameters were evaluated using ultrasonography, while the severity of dyspnea, aerobic capacity, and the amount of energy used by the body during physical activity were assessed using the six-minute walk test, mMRC scale, and Metabolic Equivalent Task (MET), respectively. We identified that 69.5% of patients had diaphragm atrophy and 6.5% had diaphragm paralysis. The percentage of atrophy was not related to age, gender, BMI, oxygen therapy usage during the COVID-19 infection course, and disease severity. Patients who experienced cough, fever, and no loss of smell during the COVID-19 course had significantly greater diaphragm inspiratory thickness values, while patients with cough and no smell disorders had a significantly lower percentage of diaphragm atrophy. Diaphragm functional parameters were strongly associated with selected variables of exercise tolerance, such as distance in the six-minute walk test, oxygen saturation levels, fatigue, and exertion on the Borg scale. In conclusion, diaphragm muscle dysfunction is a serious long-term post-COVID-19 consequence and can be viewed as a major contributing factor to prolonged functional impairments.

Correlation of diaphragmatic mobility and thickening assessed by lung ultrasound with severity of interstitial lung disease

BACKGROUND

Studies conducted in interstitial lung disease (ILD) patients to assess diaphragmatic excursion and thickening fraction suggest a weak to strong correlation with pulmonary function parameters. However, diaphragmatic excursion velocity, a novel imaging marker, has not been correlated with pulmonary function and high-resolution computed tomography (HRCT) fibrosis score in ILD patients previously.

METHODS

We conducted a cross-sectional analytical study in 40 ILD patients during quiet (QB) and deep breathing (DB) to measure diaphragmatic thickening, excursion and excursion velocity using transthoracic ultrasound and correlated them with pulmonary function parameters and HRCT fibrosis score.

RESULTS

Most diaphragm parameters in DB correlated more strongly with lung function parameters compared to quiet breathing. Right diaphragmatic excursion, during QB and DB, showed positive correlations with forced vital capacity (FVC) z-score (r = 0.591, 0.676) and diffusion capacity of the lung for carbon monoxide (DLCO) z-score (r = 0.437, 0.438), and negative correlations with HRCT fibrosis score (r = -0.439, -0.425), respectively. In addition, right diaphragmatic velocity exhibited positive correlations with FVC z-score (r = 0.388, 0.667) and DLCOz-score (r = 0.139, 0.412), and negative correlations with HRCT fibrosis score (r = -0.454, -0.445). Right diaphragm thickening fraction showed positive correlations with FVC z-score (r = 0.330, 0.460) and DLCOz-score (r = 0.400, 0.426), and negative correlations with HRCT fibrosis score (r = -0.199, -0.237). Similarly, right diaphragmatic thickness indicated positive correlations with FVC z-score (r = 0.526, 0.614) and DLCOz-score (r = 0.298, 0.298), and negative correlations with HRCT fibrosis score (r = -0.398, -0.401).

CONCLUSION

Diaphragmatic excursion velocity during DB showed a weak to moderate correlation with pulmonary function parameters and HRCT fibrosis score and may be utilized as a surrogate marker in ILD patients unable to perform pulmonary function tests or undergo sequential HRCT thorax in follow-up.

Neonatal tachypnea caused by diaphragmatic paralysis: A case report

BACKGROUND

Diaphragmatic paralysis is typically associated with phrenic nerve injury. Neonatal diaphragmatic paralysis diagnosis is easily missed because its manifestations are variable and usually nonspecific.

CASE SUMMARY

We report a 39-week-old newborn delivered via vaginal forceps who presented with tachypnea but without showing other birth-trauma-related manifestations. The infant was initially diagnosed with pneumonia. However, the newborn still exhibited tachypnea despite effective antibiotic treatment. Chest radiography revealed right diaphragmatic elevation. M-mode ultrasonography revealed decreased movement of the right diaphragm. The infant was subsequently diagnosed with diaphragmatic paralysis. After 4 weeks, tachypnea improved. Upon re-examination using M-mode ultrasonography, the difference in bilateral diaphragmatic muscle movement was smaller than before.

CONCLUSION

Appropriate use of M-mode ultrasound to quantify diaphragmatic excursions could facilitate timely diagnosis and provide objective evaluation.

Intercostal Muscle Function During Noninvasive Ventilation and Acute Hypercapnic Respiratory Failure

BACKGROUND

Noninvasive ventilation (NIV) is a widely used and well-established treatment modality for respiratory failure. In patients with increased respiratory work of breathing, accessory muscles are commonly activated along with the diaphragm. Whereas diaphragm ultrasound has been utilized to assess outcomes of mechanical ventilation, the data on intercostal muscle ultrasound remain limited. We aimed to investigate the association between intercostal muscle thickening fraction (TF) and NIV failure in critical care patients with hypercapnic respiratory failure.

METHODS

Critical care subjects receiving NIV for hypercapnic respiratory failure were enrolled in the study. The intercostal muscle TF was measured on admission day (day 0) and the following day (day 1). NIV failure was defined as the need for invasive mechanical ventilation or death during NIV therapy.

RESULTS

A total of 158 subjects were enrolled, and 30 experienced NIV failure. Age, sex, and body mass index (BMI) were similar in the NIV success and failure groups. Acute Physiology And Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) scores were higher in the NIV failure group. In terms of causes of respiratory failure, the COPD exacerbation rate was higher in the NIV success group. TF was higher in the NIV failure group on both day 0 and day 1. The increased TF on the ICU admission day, with a cutoff value of 12%, was associated with NIV failure after adjusting for age, sex, BMI, APACHE II, and SOFA. Persistence of a higher TF value on both day 0 and day 1 was also associated with NIV failure risk.

CONCLUSIONS

There was a positive relation between intercostal muscle TF measured by ultrasound and NIV failure, even after adjusting for APACHE II and SOFA scores.

Thoracic manifestations and respiratory function alterations in axial spondyloarthritis and newest possibilities of ultrasound to detect changes in diaphragm-a narrative review

Background and Objective

Axial spondyloarthritis (axSpA) includes thoracic manifestations and changes in respiratory function that require a comprehensive understanding for effective treatment. This review aims to investigate these manifestations and evaluate the role of ultrasound in detecting diaphragmatic changes to provide insights for improved diagnosis and treatment strategies in axSpA patients.

Methods

A systematic search was conducted in Index Medicus and Scopus from 2003 to 2023. Inclusion criteria included primary and secondary publications, with a focus on high-quality evidence such as randomised controlled trials and systematic reviews with or without meta-analysis. Keywords spondyloarthritis, respiratory, chest, thoracic, diaphragm and ultrasound were used in the search. A total of 22 articles were identified after duplicates, and inadequate papers were removed.

Key Content and Findings

The review included the prevalence, classification and extra-articular manifestations of axSpA, highlighting the impact on respiratory function. Thoracic manifestations and the potential impact of pharmacological interventions were detailed, and various conditions affecting respiratory dynamics were discussed. In addition, the utility of ultrasonography in assessing diaphragmatic function was explained and the techniques, parameters and measurements used to assess diaphragmatic movement, muscle thickness and respiratory mobility were described. The results illustrate the changes in diaphragmatic function in axSpA patients and their correlation with disease activity.

Conclusions

This narrative review highlights the intricate relationship between axSpA and respiratory manifestations and emphasises the significant impact on thoracic function and diaphragmatic dynamics. The utility of ultrasound in assessing diaphragmatic function offers a promising avenue for objective evaluation that provides insight into disease activity and potential therapeutic responses. This review emphasises the critical role of early diagnosis and vigilant monitoring, and advocates a multidisciplinary approach that integrates non-pharmacological interventions, particularly tailored physical activity, to maintain and improve respiratory function in axSpA patients. Increased research initiatives and awareness of pulmonary complications in axSpA are essential to optimise medical care and improve treatment outcomes in this patient group.

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

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

Point-of-Care Ultrasound to Assess Diaphragmatic Paralysis in Resource-Limited Setting: A Case Series

Diaphragmatic dysfunction can arise from various factors, and Guillain-Barre syndrome, characterized by acute inflammatory polyradiculoneuropathy, is one such cause that may result in respiratory failure due to diaphragmatic paralysis. Prompt recognition and timely intervention, including airway protection and addressing the underlying pathology, are crucial for achieving optimal patient outcomes. Point-of-care ultrasound, specifically utilizing the M-mode function, can be employed for individuals displaying symptoms of diaphragmatic paralysis. This diagnostic approach is uncomplicated an effective tool for serial follow-up. In this context, we present a case series involving three patients with diaphragmatic paralysis in a limited-resource setting.

Lung ultrasound in a nutshell. Lines, signs, some applications, and misconceptions from a radiologist's point of view. Part 2

In recent years, lung ultrasound (LUS) has developed rapidly, and it is gaining growing popularity in various scenarios. There are constant attempts to introduce it to new fields. In addition, knowledge regarding lung and LUS has been augmented by the recent COVID-19 pandemics. In the first part of this review we discuss lines, signs and pheno-mena, profiles, some applications, and misconceptions. An aim of the second part of the review is mainly to discuss some advanced applications of LUS, including lung elastography, lung spectroscopy, colour and spectral Doppler, contrast-enhanced ultrasound of lung, speckled tracking of pleura, quantification of pulmonary oedema, predicting success of talc pleurodesis, asthma exacerbations, detecting chest wall invasion by tumours, lung biopsy, estimating pleural effusion volume, and predicting mechanical ventilatory weaning outcome. For this purpose, we reviewed literature concerning LUS.

Ultrasound imaging of core muscles activity in multiparous women with vaginal laxity: a cross-sectional study

Vaginal laxity (VL) is a common condition among multiparous women, especially those who have delivered vaginally. Since pelvic floor muscles (PFMs) work synergistically with other core muscles, physical therapy protocols that aim to treat VL should train the PFMs in combination with other core muscles. To investigate the activity of core muscles in multiparous women with and without VL, and its relation to sexual function. An observational, cross-sectional study. The study included 100 multiparous women, who were divided into two groups according to their scores on the vaginal laxity questionnaire (VLQ). Women who scored between 1 and 3 on the VLQ were categorized as having VL (n = 48), while those who scored between 5 and 7 were placed in the control group (n = 52). The primary outcomes were PFM displacement, diaphragmatic excursion, transversus abdominis activation ratio, and lumbar multifidus thickness measured by ultrasound imaging. The secondary outcome was sexual functioning, evaluated using the Arabic female sexual function index (ArFSFI). The VL group had significantly lower PFM displacement (mean difference (MD) - 0.42; 95% confidence interval (CI) - 0.49 to - 0.33; p = 0.001), diaphragmatic excursion (MD - 2.75; 95% CI - 2.95 to - 2.55; p = 0.001), lumbar multifidus thickness (MD - 10.08; 95% CI - 14.32 to - 5.82; p = 0.02), and ArFSFI scores (MD - 9.2; 95% CI - 10.59 to - 7.81; p = 0.001) in comparison to the control group (p < 0.05). Nevertheless, the transversus abdominis activation ratio demonstrated no significant difference between the two groups (MD 0.06; 95% CI - 0.05 to 0.17; p = 0.33). Multiparous women with VL had significantly lower PFM displacement, diaphragmatic excursion, lumbar multifidus thickness, and sexual function index scores than women in the control group. The only exception was transversus abdominis activation, which did not differ significantly between the VL and control groups.

Relationship Between Diaphragm Thickness, Thickening Fraction, Dome Excursion, and Respiratory Pressures in Healthy Subjects: An Ultrasound Study

PURPOSE

Diaphragm ultrasonography is used to identify causes of diaphragm dysfunction. However, its correlation with pulmonary function tests, including maximal inspiratory (MIP) and expiratory pressures (MEP), remains unclear. This study investigated this relationship by measuring diaphragm thickness, thickening fraction (TF), and excursion (DE) using ultrasonography, and their relationship to MIP and MEP. It also examined the influence of age, sex, height, and BMI on these measures.

METHODS

We recruited healthy Japanese volunteers and conducted pulmonary function tests and diaphragm ultrasonography in a seated position. Diaphragm ultrasonography was performed during quiet breathing (QB) and deep breathing (DB) to measure the diaphragm thickness, TF, and DE. A multivariate analysis was conducted, adjusting for age, sex, height, and BMI.

RESULTS

Between March 2022 and January 2023, 109 individuals (56 males) were included from three facilities. The mean (standard deviation) MIP and MEP [cmH2O] were 72.2 (24.6) and 96.9 (35.8), respectively. Thickness [mm] at the end of expiration was 1.7 (0.4), TF [%] was 50.0 (25.9) during QB and 110.7 (44.3) during DB, and DE [cm] was 1.7 (0.6) during QB and 4.4 (1.4) during DB. Multivariate analysis revealed that only DE (DB) had a statistically significant relationship with MIP and MEP (p = 0.021, p = 0.008). Sex, age, and BMI had a statistically significant influence on relationships between DE (DB) and MIP (p = 0.008, 0.048, and < 0.001, respectively).

CONCLUSION

In healthy adults, DE (DB) has a relationship with MIP and MEP. Sex, age, and BMI, but not height, are influencing factors on this relationship.

Evaluation of computed tomography in the diagnosis of ultrasound-proven diaphragm dysfunction

INTRODUCTION

Computed tomography (CT) is routinely employed on the evaluation of dyspnea, yet limited data exist on its assessment of diaphragmatic muscle. This study aimed to determine the capability of CT in identifying structural changes in the diaphragm among patients with ultrasound-confirmed diaphragmatic dysfunction.

METHODS

Diaphragmatic ultrasounds conducted between 2018 and 2021 at our center in Marseille, France, were retrospectively collected. Diaphragmatic pillars were measured on CT scans at the L1 level and the celiac artery. Additionally, the difference in height between the two diaphragmatic domes in both diaphragmatic dysfunction cases and controls was measured and compared.

RESULTS

A total of 65 patients were included, comprising 24 with diaphragmatic paralysis, 13 with diaphragmatic weakness, and 28 controls. In the case group (paralysis and weakness) with left dysfunctions (n = 24), the CT thickness of the pillars at the level of L1 and the celiac artery was significantly thinner compared with controls (2.0 mm vs. 7.4 mm and 1.8 mm vs. 3.1 mm, p < 0.001 respectively). Significantly different values were observed for paralysis (but not weakness) in the right dysfunction subgroup (n = 15) (2.6 mm vs. 7.4 mm and 2.2 mm vs. 3.8 mm, p < 0.001 respectively, for paralysis vs. controls). Regardless of the side of dysfunction, a significant difference in diaphragmatic height was observed between cases and controls (7.70 cm vs. 1.16 cm and 5.51 cm vs. 1.16 cm, p < 0.001 for right and left dysfunctions, respectively). Threshold values determined through ROC curve analyses for height differences between the two diaphragmatic domes, indicative of paralysis or weakness in the right dysfunctions, were 4.44 cm and 3.51 cm, respectively. Similarly for left dysfunctions, the thresholds were 2.70 cm and 2.48 cm, respectively, demonstrating good performance (aera under the curve of 1.00, 1.00, 0.98, and 0.79, respectively).

CONCLUSION

In cases of left diaphragmatic dysfunction, as well as in paralysis associated with right diaphragmatic dysfunction, CT revealed thinner pillars. Additionally, a notable increase in the difference in diaphragmatic height demonstrated a strong potential to identify diaphragmatic dysfunction, with specific threshold values.

Revolutionizing core muscle analysis in female sexual dysfunction based on machine learning

The purpose of this study is to investigate the role of core muscles in female sexual dysfunction (FSD) and develop comprehensive rehabilitation programs to address this issue. We aim to answer the following research questions: what are the roles of core muscles in FSD, and how can machine and deep learning models accurately predict changes in core muscles during FSD? FSD is a common condition that affects women of all ages, characterized by symptoms such as decreased libido, difficulty achieving orgasm, and pain during intercourse. We conducted a comprehensive analysis of changes in core muscles during FSD using machine and deep learning. We evaluated the performance of multiple models, including multi-layer perceptron (MLP), long short-term memory (LSTM), convolutional neural network (CNN), recurrent neural network (RNN), ElasticNetCV, random forest regressor, SVR, and Bagging regressor. The models were evaluated based on mean squared error (MSE), mean absolute error (MAE), and R-squared (R2) score. Our results show that CNN and random forest regressor are the most accurate models for predicting changes in core muscles during FSD. CNN achieved the lowest MSE (0.002) and the highest R2 score (0.988), while random forest regressor also performed well with an MSE of 0.0021 and an R2 score of 0.9905. Our study demonstrates that machine and deep learning models can accurately predict changes in core muscles during FSD. The neglected core muscles play a significant role in FSD, highlighting the need for comprehensive rehabilitation programs that address these muscles. By developing these programs, we can improve the quality of life for women with FSD and help them achieve optimal sexual health.

The Role of Ultrasonography in the Process of Weaning from Mechanical Ventilation in Critically Ill Patients

Weaning patients from mechanical ventilation (MV) is a complex process that may result in either success or failure. The use of ultrasound at the bedside to assess organs may help to identify the underlying mechanisms that could lead to weaning failure and enable proactive measures to minimize extubation failure. Moreover, ultrasound could be used to accurately identify pulmonary diseases, which may be responsive to respiratory physiotherapy, as well as monitor the effectiveness of physiotherapists' interventions. This article provides a comprehensive review of the role of ultrasonography during the weaning process in critically ill patients.

Differences of diaphragmatic muscle contraction between female patients with chronic neck pain and asymptomatic controls: A case-control study based on ultrasonography

BACKGROUND

Recent systematic reviews and meta-analyses show that individuals with chronic neck pain (CNP) have altered respiratory muscle strength and abnormal respiratory mechanics. However, no study has investigated the diaphragmatic function in individuals with CNP compared to asymptomatic peers.

OBJECTIVES

This study aimed to compare the respiratory muscle strength and diaphragmatic function between patients with CNP and asymptomatic controls.

DESIGN

Observational, case-control study.

METHODS

A total of 25 women with CNP and 23 asymptomatic controls participated in this case-control study. The visual analog scale and neck disability index were used to assess the pain and disability characteristics of the CNP group. Maximum inspiratory and expiratory pressures (MIP and MEP) were measured to determine respiratory muscle strengths. The diaphragmatic function (muscle thickness in deep inspiration, Tins; and at the end of calm expiration, Texp; muscle thickness change, ΔT; contraction ratio, CR) were evaluated by two-dimensional ultrasonography.

RESULTS

The MIP (p = 0.001, d = 1.11), ΔT (p = 0.033, d = 0.63), and CR (p = 0.012, d = 0.75) of the diaphragm were found significantly reduced in the CNP group compared to asymptomatic controls whilst MEP, Tins, and Texp of the diaphragm were similar between study groups (p > 0.05). The intensity of neck pain was moderately correlated with MIP (r = -0.48), Tins (r = -0.46), and ΔT (r = -0.42) while NDI (r = -0.42) had a moderate correlation with Tins (p < 0.05).

CONCLUSION

The present findings revealed that women with CNP have altered diaphragmatic function. Thus, screening and targeting diaphragm may improve the rehabilitation process in CNP. However, further experimental studies regarding the efficacy of breathing exercise approaches are needed.

Diaphragm Ultrasonography: Reference Values and Influencing Factors for Thickness, Thickening Fraction, and Excursion in the Seated Position

INTRODUCTION

Measurements of diaphragm function by ultrasonography are affected by body position, but reference values in the seated position have not been established for an Asian population. This study aimed to determine reference values for diaphragm thickness, thickening fraction, and dome excursion by ultrasonography and to investigate the effects of sex, height, and body mass index.

METHODS

Diaphragm ultrasonography was performed on 109 seated Japanese volunteers with normal respiratory function who were enrolled between March 2022 and January 2023. Thickness, thickening fraction, and excursion were measured. Reference values and the measurement success rate were calculated. Multivariate analysis adjusted for sex, height, and body mass index was performed.

RESULTS

The measurement success rate was better for thickness than for excursion. The mean (lower limit of normal) values on the right/left sides were as follows. During quiet breathing, thickness at end expiration(mm) was 1.7 (0.9)/1.6 (0.80), thickening fraction(%) was 50 (0.0)/52 (0.0), and excursion(cm) was 1.7 (0.5)/1.9 (0.5). During deep breathing, the thickening fraction was 111 (24)/107 (22), and the excursion was 4.4 (1.7)/4.1 (2.0). In multivariate analysis, body mass index was positively associated with thickness but not with the thickening fraction.

CONCLUSION

The reference values in this study were smaller than those in previous reports from Europe. Considering that thickness is influenced by body mass index, using Western reference values in Asia, where the average body mass index is lower, might not be appropriate. The thickening fraction in deep breathing is unaffected by other items and can be used more universally.

Replacement of fluoroscopy by ultrasonography in the evaluation of hemidiaphragm function, an exploratory prospective study

INTRODUCTION

Dysfunction of the diaphragm may ultimately lead to respiratory insufficiency and compromise patient outcome. Evaluation of diaphragm function is cumbersome. Fluoroscopy has been the gold standard to measure diaphragmatic excursion. Ultrasonography can visualize diaphragm excursion and holds many advantages such as no radiation exposure, increased portability and accessibility. However, correlation between fluoroscopy and ultrasonography has never been studied. We aimed to compare fluoroscopic and ultrasound measures of diaphragm excursion to determine if ultrasonography can replace fluoroscopy.

METHODS

We performed ultrasound and fluoroscopy simultaneously during sniff inspiration and at total inspiratory capacity in patients with chronic obstructive pulmonary disease, heart failure and in healthy volunteers. Cranio-caudal excursion was measured by fluoroscopy and compared directly to M-mode excursion, B-mode excursion, area change, resting thickness, thickening fraction and contraction velocity measured by ultrasonography.

RESULTS

Forty-two participants were included. The Pearson correlation between M-mode and fluoroscopy excursion was 0.61. The slope was 0.9 (90%CI 0.76-1.04) in a regression analysis. Using the Bland-Altman method, the bias was - 0.39 cm (95% CI - 1.04-0.26), p = 0.24. The Pearson correlation between fluoroscopy and B-mode and area change ultrasonography was high; low for thickness and fraction. All correlations were lower during sniff inspiration compared with inspiratory capacity breathing.

CONCLUSION

Ultrasonography has an acceptable correlation and bias compared to fluoroscopy and can thus be used as the primary tool to evaluate diaphragm excursion.

Prognostic Value of Diaphragmatic Ultrasound in Patients Admitted for COVID-19 Pneumonia

Introduction

COVID-19 pneumonia results in an impairment of the diaphragmatic musculature that influences the development of respiratory failure during the patient's hospitalization. Diaphragmatic ultrasound is a useful, non-invasive, and accessible tool for measuring the function of this muscle.

Objective

Assessing the morphological and functional ultrasound status of the diaphragm in patients admitted within the first 24 h for COVID-related pneumonia and its association with hospital morbidity and mortality (NCT05805579).

Material and methods

Observational, prospective cohort study that included 68 patients admitted for COVID-19 pneumonia with respiratory failure. Diaphragmatic ultrasound was performed within the first 24 h of admission to the pulmonology ward. Clinical, analytical, and ultrasound variables were collected: excursion, thickness, and diaphragmatic shortening fraction (DSF). DSF < 20% was used to define diaphragmatic dysfunction (DD). Patients who showed favorable progression and were managed on the ward (HCONV) were compared to those who required admission to the respiratory monitoring unit (RMU).

Results

A total of 68 patients were included, of which 22 (32.35%) were admitted to the RMU. Diaphragmatic excursion at maximum volume was higher in the HCONV group compared to the RMU group (58.41 ± 17.83 vs. 50.03 ± 16.23; p = 0.123). Diaphragmatic dysfunction (DD) was observed in 21 (30.88%) patients, with a higher prevalence in the RMU group than in the HCONV group (15 (68.18%) vs. 6 (13.04%); p = 0.0001). In the multivariate analysis, age and DSF at admission were the best predictors of failure to discharge.

Conclusions

Performing diaphragmatic ultrasound to assess mobility and DSF within the first 24 h of admission for COVID-19 pneumonia proves valuable in determining short-term progression and the need for admission to a respiratory monitoring unit.

Multi-task localization of the hemidiaphragms and lung segmentation in portable chest X-ray images of COVID-19 patients

Background

The COVID-19 can cause long-term symptoms in the patients after they overcome the disease. Given that this disease mainly damages the respiratory system, these symptoms are often related with breathing problems that can be caused by an affected diaphragm. The diaphragmatic function can be assessed with imaging modalities like computerized tomography or chest X-ray. However, this process must be performed by expert clinicians with manual visual inspection. Moreover, during the pandemic, the clinicians were asked to prioritize the use of portable devices, preventing the risk of cross-contamination. Nevertheless, the captures of these devices are of a lower quality.

Objectives

The automatic quantification of the diaphragmatic function can determine the damage of COVID-19 on each patient and assess their evolution during the recovery period, a task that could also be complemented with the lung segmentation.

Methods

We propose a novel multi-task fully automatic methodology to simultaneously localize the position of the hemidiaphragms and to segment the lung boundaries with a convolutional architecture using portable chest X-ray images of COVID-19 patients. For that aim, the hemidiaphragms' landmarks are located adapting the paradigm of heatmap regression.

Results

The methodology is exhaustively validated with four analyses, achieving an 82.31% ± 2.78% of accuracy when localizing the hemidiaphragms' landmarks and a Dice score of 0.9688 ± 0.0012 in lung segmentation.

Conclusions

The results demonstrate that the model is able to perform both tasks simultaneously, being a helpful tool for clinicians despite the lower quality of the portable chest X-ray images.

Computed tomographic diaphragmatic thickness: a promising method for the evaluation of diaphragmatic muscle in cardiopulmonary diseased cats

Diaphragmatic dysfunction (DD) is defined as a weakening of the diaphragmatic muscle and can be an undetected cause of dyspnea. The objectives of this study were to explore the appropriate diaphragmatic location, measure diaphragmatic thickness (DT), evaluate the effect of intrinsic factors on DT, and compare DT between healthy and diseased cats, using 33 healthy cats and 15 diseased cats. A retrospective, analytical, case-control study using thoraco-abdominal feline computed tomography (CT) was performed. Two radiologists independently reviewed all images to verify inter- and intra-observer reliabilities and the best position for measuring DT. The effects of sex, age, and body weight were also studied, and cutoff values for detecting DT abnormalities were established. The results showed that the appropriate location for DT measurement was at the ventral border of the cranial endplate of the first lumbar vertebral body (L1) due to its highest intra- and inter-observer reliabilities. At this location, a significant difference in DT between the right and left hemidiaphragms (p = 0.01) was observed. Only sex had an impact on DT values. Interestingly, the DTs of cardiorespiratory-affected cats, both on the right and left sides, were significantly thinner than those of healthy cats. In conclusion, CT imaging is a reliable imaging method for determining diaphragmatic muscular atrophy. The ventral border of the cranial endplate of L1 is recommended for measuring the DT, and sex was the only factor affecting the DT measurement.

Chest ultrasound findings in hepatopulmonary fusion (HPF)

Hepatopulmonary fusion (HPF) is an extremely rare condition characterized by a fusion between the herniated liver and lung right parenchyma. Knowledge about this condition comes from the few cases reported in the literature (less than 40 cases). While diagnostic evaluation as X-Ray, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and Single Photon Emission Computed Tomography (SPECT) were described, poor ultrasound findings are available. In this paper, the authors provide the detailed chest ultrasound findings of this rare condition.

Evaluation of the Breastfeeding Dynamics of Neonates with Ankyloglossia via a Novel Ultrasonographic Technique

To effectively address breastfeeding issues for neonates and mothers, one must understand the physiology of breastfeeding and the anatomical components involved in sucking, swallowing, and respiration. This study compared the tongue position and movement of neonates with tongue ties versus healthy controls during sucking. A new objective ultrasonography diagnostic approach was also introduced for the orofacial region. This retrospective study evaluated B-mode and M-mode ultrasonography images from 30 neonates clinically diagnosed with tongue tie, and a control group of 30 neonates. B-mode ultrasound images were used to examine several characteristics to locate the nipple in the oral cavity during breastfeeding. Anatomic M-mode ultrasound images were used to assess tongue movement during sucking. The nipple moved farther from the intersection of the hard and soft palates during the sucking cycle in the ankyloglossia group than in the control group (p < 0.05). Compared to the control group, neonates with ankyloglossia have a lower capacity to lift the anterior tongue toward the palate when sucking (p < 0.05). There was no significant difference in tongue movement metrics between the two groups (p > 0.05). Our findings were consistent with earlier research. The novel measurement method will offer a new perspective on breastfeeding.

Ultrasonographic evaluation of diaphragmatic excursion changes after major laparoscopic surgeries in the Trendelenburg position under general anaesthesia: A prospective observational study

Background and Aims

Laparoscopic surgeries result in increased intra abdominal pressure and cephalad displacement of the diaphragm. The Trendelenburg position can augment these respiratory changes. The primary objective of this study was to compare diaphragmatic excursions before and after a major laparoscopic pelvic surgery under general anaesthesia in the Trendelenburg position using ultrasonography (USG).

Methods

This prospective observational study included 90 patients of either gender, aged 20-60 years, with American Society of Anesthesiologists physical status I/II. M-mode USG was used to assess diaphragm inspiratory amplitude (DIA) before induction of anaesthesia and 10 minutes after tracheal extubation. Factors such as age, gender, body mass index, positive end-expiratory pressure (PEEP), pain, peak airway pressures, duration of pneumoperitoneum, duration and degree of Trendelenburg position and duration of anaesthesia were recorded. Pearson's correlation and multiple linear regression were used to analyse the factors affecting change in DIA (ΔDIA).

Results

The mean difference (95% confidence interval (CI)) of measured DIA was 0.70 (0.598-0.809), P < 0.001. ΔDIA had a weak positive significant correlation with age, anaesthesia duration, pneumoperitoneum, and visual analogue scale (VAS) score 10 minutes after extubation. Multiple linear regression analysis showed 14.86% of the variance in DIA. Age (β = 0.008, P = 0.049), duration of anaesthesia (β = 0.002, P = 0.02) and VAS score 10 minutes after extubation (β = 0.128, P = 0.001) were significant independent predictors.

Conclusion

DIA decreased significantly after pelvic laparoscopic surgeries performed in the Trendelenburg position. Age, duration of anaesthesia and pain after the procedure were significant independent predictors.

Early detection and assessment of intensive care unit-acquired weakness: a comprehensive review

Intensive care unit-acquired weakness (ICU-AW) is a serious complication in critically ill patients. Therefore, timely and accurate diagnosis and monitoring of ICU-AW are crucial for effectively preventing its associated morbidity and mortality. This article provides a comprehensive review of ICU-AW, focusing on the different methods used for its diagnosis and monitoring. Additionally, it highlights the role of bedside ultrasound in muscle assessment and early detection of ICU-AW. Furthermore, the article explores potential strategies for preventing ICU-AW. Healthcare providers who manage critically ill patients utilize diagnostic approaches such as physical exams, imaging, and assessment tools to identify ICU-AW. However, each method has its own limitations. The diagnosis of ICU-AW needs improvement due to the lack of a consensus on the appropriate approach for its detection. Nevertheless, bedside ultrasound has proven to be the most reliable and cost-effective tool for muscle assessment in the ICU. Combining the Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation (APACHE) II score assessment, and ultrasound can be a convenient approach for the early detection of ICU-AW. This approach can facilitate timely intervention and prevent catastrophic consequences. However, further studies are needed to strengthen the evidence.

Ultrasonic Evaluation of Diaphragm in Patients with Systemic Sclerosis

The diaphragm is the most important muscle in respiration. Nevertheless, its function is rarely evaluated. Patients with systemic sclerosis (SSc) could be at risk of diaphragmatic dysfunction because of multiple factors. These patients often develop interstitial lung disease (SSc-ILD) and earlier studies have indicated that patients with different ILDs have decreased diaphragmatic mobility on ultrasound (US). This study aimed to evaluate diaphragmatic function in SSc patients using US with regard to the ILD, evaluated with the Warrick score on high-resolution computed tomography (HRCT), and to investigate associations between ultrasonic parameters and dyspnea, lung function, and other important clinical parameters. In this cross-sectional study, we analyzed diaphragm mobility, thickness, lung function, HRCT findings, Modified Medical Research Council (mMRC) dyspnea scale, modified Rodnan skin score (mRSS), autoantibodies, and esophageal diameters on HRCT in patients with SSc. Fifty patients were enrolled in the study. Patients with SSc-ILD had lower diaphragmatic mobility in deep breathing than patients without ILD. The results demonstrated negative correlations between diaphragmatic mobility and mMRC, mRSS, anti-Scl-70 antibodies, esophageal diameters on HRCT, and a positive correlation with lung function. Patients with SSc who experience dyspnea should be evaluated for diaphragmatic dysfunction for accurate symptom phenotyping and personalized pulmonary rehabilitation treatment.

Spinal cord perfusion pressure correlates with breathing function in patients with acute, cervical traumatic spinal cord injuries: an observational study

OBJECTIVE

This study aims to determine the relationship between spinal cord perfusion pressure (SCPP) and breathing function in patients with acute cervical traumatic spinal cord injuries.

METHODS

We included 8 participants without cervical TSCI plus 13 patients with cervical traumatic spinal cord injuries, American Spinal Injury Association Impairment Scale grades A-C. In the TSCI patients, we monitored intraspinal pressure from the injury site for up to a week and computed the SCPP as mean arterial pressure minus intraspinal pressure. Breathing function was quantified by diaphragmatic electromyography using an EDI (electrical activity of the diaphragm) nasogastric tube as well as by ultrasound of the diaphragm and the intercostal muscles performed when sitting at 20°-30°.

RESULTS

We analysed 106 ultrasound examinations (total 1370 images/videos) and 198 EDI recordings in the patients with cervical traumatic spinal cord injuries. During quiet breathing, low SCPP (< 60 mmHg) was associated with reduced EDI-peak (measure of inspiratory effort) and EDI-min (measure of the tonic activity of the diaphragm), which increased and then plateaued at SCPP 60-100 mmHg. During quiet and deep breathing, the diaphragmatic thickening fraction (force of diaphragmatic contraction) plotted versus SCPP had an inverted-U relationship, with a peak at SCPP 80-90 mmHg. Diaphragmatic excursion (up and down movement of the diaphragm) during quiet breathing did not correlate with SCPP, but diaphragmatic excursion during deep breathing plotted versus SCPP had an inverse-U relationship with a peak at SCPP 80-90 mmHg. The thickening fraction of the intercostal muscles plotted versus SCPP also had inverted-U relationship, with normal intercostal function at SCPP 80-100 mmHg, but failure of the upper and middle intercostals to contract during inspiration (i.e. abdominal breathing) at SCPP < 80 or > 100 mmHg.

CONCLUSIONS

After acute, cervical traumatic spinal cord injuries, breathing function depends on the SCPP. SCPP 80-90 mmHg correlates with optimum diaphragmatic and intercostal muscle function. Our findings raise the possibility that intervention to maintain SCPP in this range may accelerate ventilator liberation which may reduce stay in the neuro-intensive care unit.

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.

Thoracic Ultrasound in COVID-19: Use of Lung and Diaphragm Ultrasound in Evaluating Dyspnea in Survivors of Acute Respiratory Distress Syndrome from COVID-19 Pneumonia in a Post-ICU Clinic

INTRODUCTION

Dyspnea is a common symptom in survivors of severe COVID-19 pneumonia. While frequently employed in hospital settings, the use of point-of-care ultrasound in ambulatory clinics for dyspnea evaluation has rarely been explored. We aimed to determine how lung ultrasound score (LUS) and inspiratory diaphragm excursion (DE) correlate with patient-reported dyspnea during a 6-min walk test (6MWT) in survivors of COVID-19 acute respiratory distress syndrome (ARDS). We hypothesize higher LUS and lower DE will correlate with dyspnea severity.

STUDY DESIGN AND METHODS

Single-center cross-sectional study of survivors of critically ill COVID-19 pneumonia (requiring high-flow nasal cannula, invasive, or non-invasive mechanical ventilation) seen in our Post-ICU clinic. All patients underwent standardized scanning protocols to compute LUS and DE. Pearson correlations were performed to detect an association between LUS and DE with dyspnea at rest and exertion during 6MWT.

RESULTS

We enrolled 45 patients. Average age was 61.5 years (57.7% male), with average BMI of 32.3 Higher LUS correlated significantly with dyspnea, at rest (r =  + 0.41, p =  < 0.01) and at exertion (r =  + 0.40, p =  < 0.01). Higher LUS correlated significantly with lower oxygen saturation during 6MWT (r = -0.55, p =  < 0.01) and lower 6MWT distance (r = -0.44, p =  < 0.01). DE correlated significantly with 6MWT distance but did not correlate with dyspnea at rest or exertion.

CONCLUSION

Higher LUS correlated significantly with patient-reported dyspnea at rest and exertion. Higher LUS significantly correlated with more exertional oxygen desaturation during 6MWT and lower 6MWT distance. DE did not correlate with dyspnea.

Technical Report

Diaphragmatic structure and function assessment can be performed using grayscale as well as M-mode ultrasound. This article discusses the application of M-mode ultrasound in the assessment of diaphragmatic dysfunction.