• Diaphragm
• Diaphragm ultrasound
• Diaphragmatic dysfunction
• Diaphragmatic excursion
• Point-of-care-ultrasound
• Respiratory failure

• Humans
• Diaphragm/diagnostic imaging
• Diaphragm/physiopathology
• Ultrasonography/methods
• Ultrasonography/trends
• Respiratory Insufficiency/diagnostic imaging
• Pulmonary Disease, Chronic Obstructive

• breathing
• cardiac rehabilitation
• cardiovascular disease
• diaphragm
• myocardial infarction
• physiotherapy

• Italian Ministry of Health

• diaphragm
• diaphragm dysfunction
• non-critically ill patients
• perioperative period
• ultrasound
• ultrasound application
• ultrasound indicators

• diaphragm dysfunction
• heart failure
• hospitalized patients
• respiratory failure
• sarcopenia
• ultrasound imaging

• Diaphragm
• Duchenne muscular dystrophy
• Muscle function
• Shear wave elasticity imaging
• Ultrasonography

• Mice
• Animals
• Mice, Inbred mdx
• Diaphragm/diagnostic imaging
• Diaphragm/pathology
• Mice, Inbred C57BL
• Muscular Dystrophy, Duchenne/diagnostic imaging
• Muscular Dystrophy, Duchenne/pathology
• Muscle, Skeletal/pathology
• Elasticity
• Disease Models, Animal

• R01 AR062368 NIAMS NIH HHS
• R56 AG063928 NIA NIH HHS
• R21 AR072287 NIAMS NIH HHS
• F32 HL140821 NHLBI NIH HHS
• R01 NS117613 NINDS NIH HHS
• R01 AG072309 NIA NIH HHS

• Blood gases
• Diaphragm
• Diaphragm dysfunction
• Ultrasound
• X-ray

Skeletal muscle atrophy is prevalent and remarkably increases the risk of cardiovascular (CV) events and mortality in hemodialysis (HD) patients. However, whether diaphragm dysfunction predicts clinical outcomes in HD patients is unknown. This was a prospective cohort study of 103 HD patients. After assessment of diaphragm function by ultrasonography and collection of other baseline data, a 36-month follow-up was then initiated. Participants were divided into diaphragm dysfunction (DD+) group and normal diaphragm function (DD−) group, according to cutoff value of thickening ratio (i.e. the change ratio of diaphragm thickness) at force respiration. The primary endpoint was the first nonfatal CV event or all-cause mortality. A secondary endpoint was less serious CV events (LSCEs, a composite of heart failure readmission, cardiac arrhythmia or myocardial ischemia needed pharmacological intervention in hospital). 98 patients were eligible to analysis and 57 (58.16%) were men. 28 of 44 patients(63.64%) in DD+ group and 23 of 54 patients (42.59%) in DD− group had at least one nonfatal CV event or death (p = 0.038). Compared to DD− group, DD+ group had significantly higher incidence of LSCEs (21 vs.14, p = 0.025) and shorter survival time (22.02 ± 12.98 months vs. 26.74 ± 12.59 months, p = 0.046). Kaplan–Meier analysis revealed significantly higher risks of primary endpoint (p = 0.039), and LSCEs (p = 0.040) in DD+ group. Multivariate hazard analysis showed that DD+ group had significantly higher risk of primary endpoint [hazard ratio (HR) 1.59; 95% confident interval (CI) 1.54–1.63], and LSCEs (HR 1.47; 95%CI 1.40–1.55). Ultrasound-assessed diaphragm dysfunction predicts clinical outcomes in HD patients.

Trial registration: This study was registered with Chinese Clinical Trials Registry (www.chictr.org.cn) as ChiCTR1800016500 on Jun 05, 2018.

• Diaphragm excursion
• Diaphragm thickness
• Diaphragm ultrasound
• Pediatrics
• Respiratory muscle function

The current imaging gold standard for detecting paradoxical diaphragm motion and diagnosing hemidiaphragm paralysis is to perform the fluoroscopic sniff test. The images are visually examined by an experienced radiologist, and if one hemidiaphragm ascends while the other descends, then it is described as paradoxical motion, which is highly suggestive of hemidiaphragm paralysis. However, diagnosis can be challenging because diaphragm motion during sniffing is fast, paradoxical motion can be subtle, and the analysis is based on a 2-dimensional projection of a 3-dimensional surface. This paper presents a case of chronic left hemidiaphragm elevation that was initially reported as mild paradoxical motion on fluoroscopy. After measuring the elevations of the diaphragms and modeling their temporal correlation using Gaussian process regression, the systematic trend of the hemidiaphragmatic motion along with its stochastic properties was determined. When analyzing the trajectories of the hemidiaphragms, no statistically significant paradoxical motion was detected. This could potentially change the prognosis if the patient was to consider diaphragm plication as treatment. The presented method provides a more objective analysis of hemidiaphragm motions and can potentially improve diagnostic accuracy.

• Diaphragm fluoroscopy
• Diaphragm paralysis
• Fluoroscopic sniff test
• Gaussian process
• Hemidiaphragm elevation
• Machine learning

In cardiac surgery, patients are at risk of phrenic nerve injury, which leads to diaphragm dysfunction and acute respiratory failure. Diaphragm dysfunction (DD) is relatively frequent in cardiac surgery and particularly affects patients after coronary artery bypass graft. The onset of DD affects patients’ prognosis in term of weaning from mechanical ventilation and hospital length of stay. The authors present a narrative review about diaphragm physiology, techniques used to assess diaphragm function, and the clinical application of diaphragm ultrasound in patients undergoing cardiac surgery.

Ventilatory failure, due to the progressive wasting of respiratory muscles, is the main cause of death in patients with Duchenne muscular dystrophy (DMD). Reliable measures of lung function and respiratory muscle action are important to monitor disease progression, to identify early signs of ventilatory insufficiency and to plan individual respiratory management. Moreover, the current development of novel gene-modifying and pharmacological therapies highlighted the urgent need of respiratory outcomes to quantify the effects of these therapies. Pulmonary function tests represent the standard of care for lung function evaluation in DMD, but provide a global evaluation of respiratory involvement, which results from the interaction between different respiratory muscles. Currently, research studies have focused on finding novel outcome measures able to describe the behavior of individual respiratory muscles. This review overviews the measures currently identified in clinical research to follow the progressive respiratory decline in patients with DMD, from a global assessment to an individual structure–function muscle characterization. We aim to discuss their strengths and limitations, in relation to their current development and suitability as outcome measures for use in a clinical setting and as in upcoming drug trials in DMD.

• DMD
• imaging
• pulmonary function testing
• respiratory function
• respiratory muscles

• All ages
• LAMA2
• Laminin subunit α2 deficiency
• Merosin-deficient congenital muscular dystrophy type 1A (MDC1A)
• Natural history
• Outcome measures
• SELENON
• SEPN1
• Trial readiness

• Adult
• Child
• Humans
• Laminin/genetics
• Magnetic Resonance Imaging
• Muscular Dystrophies/genetics
• Muscular Dystrophies/therapy
• Outcome Assessment, Health Care
• Prospective Studies

• SvS2019001 stichting spieren voor spieren
• not applicable stichting voor sara
• 2018-15 stichting stofwisselkracht

• Doppler tissue imaging
• diaphragm
• mechanical ventilator weaning

• Adult
• Airway Extubation
• Diaphragm/diagnostic imaging
• Humans
• Kinetics
• Respiration, Artificial
• Ventilator Weaning

• Diaphragm weakness
• Lung lung function testing
• Neuromuscular disease
• Respiratory physiology

• Aged
• Cross-Sectional Studies
• Diaphragm/diagnostic imaging
• Diaphragm/physiopathology
• Female
• Humans
• Male
• Middle Aged
• Neuromuscular Diseases/diagnosis
• Posture/physiology
• Respiratory Physiological Phenomena
• Sitting Position
• Supine Position
• Vital Capacity/physiology

Chest ultrasonography has proven to be useful in the diagnosis of diaphragm dysfunction. The aim of the present study was to determine the normal values of the motion of both hemidiaphragms recorded by M-mode ultrasonography.

Healthy volunteers were studied while in a seated position. Diaphragmatic excursions and diaphragm profiles were measured during quiet breathing, voluntary sniffing and deep breathing. Diaphragmatic excursions were assessed by M-mode ultrasonography, using an approach perpendicular to the posterior part of the diaphragm. Anatomical M-mode was used for the recording of the complete excursion during deep breathing.

The study included 270 men and 140 women. The diaphragmatic motions during quiet breathing and voluntary sniffing were successfully recorded in all of the participants. The use of anatomical M-mode was particularly suitable for measurement of the entire diaphragmatic excursion during deep breathing. The statistical analysis showed that the diaphragmatic excursions were larger in men compared to women, supporting the determination of normal values based on sex. The lower and upper limits of normal excursion were determined for men and women for both hemidiaphragms during the three manoeuvres that were investigated. The lower limits of normal diaphragmatic excursions during deep breathing should be used to detect diaphragmatic hypokinesia, i.e. 3.3 and 3.2 cm in women and 4.1 and 4.2 cm in men for the right and the left sides, respectively.

The normal values of the diaphragmatic motion and the lower and upper limits of normal excursion can be used by clinicians to detect diaphragmatic dysfunction.

These normal values of diaphragmatic motion, and the lower and upper limits of normal excursion, can be used by physicians to detect diaphragm hypokinesia and hyperkinesia, and thus diagnose diaphragmatic dysfunctionhttps://bit.ly/35R9OFk

Diaphragm muscle dysfunction is increasingly recognized as an important element of several diseases including neuromuscular disease, chronic obstructive pulmonary disease and diaphragm dysfunction in critically ill patients. Functional evaluation of the diaphragm is challenging. Use of volitional maneuvers to test the diaphragm can be limited by patient effort. Non-volitional tests such as those using neuromuscular stimulation are technically complex, since the muscle itself is relatively inaccessible. As such, there is a growing interest in using imaging techniques to characterize diaphragm muscle dysfunction. Selecting the appropriate imaging technique for a given clinical scenario is a critical step in the evaluation of patients suspected of having diaphragm dysfunction. In this review, we aim to present a detailed analysis of evidence for the use of ultrasound and non-ultrasound imaging techniques in the assessment of diaphragm dysfunction. We highlight the utility of the qualitative information gathered by ultrasound imaging as a means to assess integrity, excursion, thickness, and thickening of the diaphragm. In contrast, quantitative ultrasound analysis of the diaphragm is marred by inherent limitations of this technique, and we provide a detailed examination of these limitations. We evaluate non-ultrasound imaging modalities that apply static techniques (chest radiograph, computerized tomography and magnetic resonance imaging), used to assess muscle position, shape and dimension. We also evaluate non-ultrasound imaging modalities that apply dynamic imaging (fluoroscopy and dynamic magnetic resonance imaging) to assess diaphragm motion. Finally, we critically review the application of each of these techniques in the clinical setting when diaphragm dysfunction is suspected.

• Diaphragm dysfunction
• Dynamic imaging techniques
• Mechanical ventilation
• Neuromuscular disorders
• Phrenic nerve
• Static imaging techniques
• Ultrasound imaging

• diaphragmatic electroneuromyography
• lung function testing
• phrenic nerve conduction
• transdiaphragmatic pressures
• unilateral diaphragmatic paralysis

Diaphragm dysfunction is highly prevalent in mechanically ventilated patients. Recent work showed that changes in diaphragm shear modulus (ΔSMdi) assessed using ultrasound shear wave elastography (SWE) are strongly related to changes in Pdi (ΔPdi) in healthy subjects. The aims of this study were to investigate the relationship between ΔSMdi and ΔPdi in mechanically ventilated patients, and whether ΔSMdi is responsive to change in respiratory load when varying the ventilator settings.

A prospective, monocentric study was conducted in a 15-bed ICU. Patients were included if they met the readiness-to-wean criteria. Pdi was continuously monitored using a double-balloon feeding catheter orally introduced. The zone of apposition of the right hemidiaphragm was imaged using a linear transducer (SL10-2, Aixplorer, Supersonic Imagine, France). Ultrasound recordings were performed under various pressure support settings and during a spontaneous breathing trial (SBT). A breath-by-breath analysis was performed, allowing the direct comparison between ΔPdi and ΔSMdi. Pearson’s correlation coefficients (r) were used to investigate within-individual relationships between variables, and repeated measure correlations (R) were used for determining overall relationships between variables. Linear mixed models were used to compare breathing indices across the conditions of ventilation.

Thirty patients were included and 930 respiratory cycles were analyzed. Twenty-five were considered for the analysis. A significant correlation was found between ΔPdi and ΔSMdi (R = 0.45, 95% CIs [0.35 0.54], p < 0.001). Individual correlation displays a significant correlation in 8 patients out of 25 (r = 0.55–0.86, all p < 0.05, versus r = − 0.43–0.52, all p > 0.06). Changing the condition of ventilation similarly affected ΔPdi and ΔSMdi. Patients in which ΔPdi–ΔSMdi correlation was non-significant had a faster respiratory rate as compared to that of patient with a significant ΔPdi–ΔSMdi relationship (median (Q1–Q3), 25 (18–33) vs. 21 (15–26) breaths.min⁻¹, respectively).

We demonstrate that ultrasound SWE may be a promising surrogate to Pdi in mechanically ventilated patients. Respiratory rate appears to negatively impact SMdi measurement. Technological developments are needed to generalize this method in tachypneic patients.

NCT03832231.

• Diaphragm
• Diaphragm dysfunction
• Intensive care unit
• Mechanical ventilation
• Shear wave elastography
• Transdiaphragmatic pressure
• Ultrasound imaging

The diaphragm is the main muscle of respiration, acting continuously and uninterruptedly to sustain the task of breathing. Diaphragmatic dysfunction can occur secondary to numerous pathological conditions and is usually underdiagnosed in clinical practice because of its nonspecific presentation. Although several techniques have been used in evaluating diaphragmatic function, the diagnosis of diaphragmatic dysfunction is still problematic. Diaphragmatic ultrasound has gained importance because of its many advantages, including the fact that it is noninvasive, does not expose patients to radiation, is widely available, provides immediate results, is highly accurate, and is repeatable at the bedside. Various authors have described ultrasound techniques to assess diaphragmatic excursion and diaphragm thickening in the zone of apposition. Recent studies have proposed standardization of the methods. This article reviews the usefulness of ultrasound for the evaluation of diaphragmatic function, addressing the details of the technique, the main findings, and the clinical applications.

Late-onset Pompe disease (LOPD) is an autosomal recessive lysosomal storage disease. Clinical features include skeletal muscle deficiency and diaphragm weakness. Clinical management relies on supportive treatment and mechanical ventilation in patients with chronic respiratory failure. M mode ultrasound and sniff tissue Doppler imaging can be used to assess and follow diaphragm function.

Rationale: Tissue Doppler imaging (TDI) is an echocardiographic method that measures the velocity of moving tissue.

Objectives: We applied this technique to the diaphragm to assess the velocity of diaphragmatic muscle motion during contraction and relaxation.

Methods: In 20 healthy volunteers, diaphragmatic TDI was performed to assess the pattern of diaphragmatic motion velocity, measure its normal values, and determine the intra- and interobserver variability of measurements. In 116 consecutive ICU patients, diaphragmatic excursion, thickening, and TDI parameters of peak contraction velocity, peak relaxation velocity, velocity–time integral, and TDI-derived maximal relaxation rate were assessed during weaning. In a subgroup of 18 patients, transdiaphragmatic pressure (Pdi)-derived parameters (peak Pdi, pressure–time product, and diaphragmatic maximal relaxation rate) were recorded simultaneously with TDI.

Measurements and Main Results: In terms of reproducibility, the intercorrelation coefficients were >0.89 for all TDI parameters (P < 0.001). Healthy volunteers and weaning success patients exhibited lower values for all TDI parameters compared with weaning failure patients, except for velocity–time integral, as follows: peak contraction velocity, 1.35 ± 0.34 versus 1.50 ± 0.59 versus 2.66 ± 2.14 cm/s (P < 0.001); peak relaxation velocity, 1.19 ± 0.39 versus 1.53 ± 0.73 versus 3.36 ± 2.40 cm/s (P < 0.001); and TDI-maximal relaxation rate, 3.64 ± 2.02 versus 10.25 ± 5.88 versus 29.47 ± 23.95 cm/s² (P < 0.001), respectively. Peak contraction velocity was strongly correlated with peak transdiaphragmatic pressure and pressure–time product, whereas Pdi-maximal relaxation rate was significantly correlated with TDI-maximal relaxation rate.

Conclusions: Diaphragmatic tissue Doppler allows real-time assessment of the diaphragmatic tissue motion velocity. Diaphragmatic TDI-derived parameters differentiate patients who fail a weaning trial from those who succeed and correlate well with Pdi-derived parameters.

• diaphragmatic ultrasonography
• velocity of diaphragmatic motion
• weaning

• Humans
• Musculoskeletal Diseases/diagnosis
• Musculoskeletal Diseases/diagnostic imaging
• Musculoskeletal Diseases/therapy
• Musculoskeletal System/diagnostic imaging
• Musculoskeletal System/pathology
• Physical Therapists
• Physicians
• Ultrasonography/methods

This article reports the various methods used to assess diaphragmatic function by ultrasonography. The excursions of the two hemidiaphragms can be measured using two-dimensional or M-mode ultrasonography, during respiratory maneuvers such as quiet breathing, voluntary sniffing and deep inspiration. On the zone of apposition to the rib cage for both hemidiaphragms, it is possible to measure the thickness on expiration and during deep breathing to assess the percentage of thickening during inspiration. These two approaches make it possible to assess the quality of the diaphragmatic function and the diagnosis of diaphragmatic paralysis or dysfunction. These methods are particularly useful in circumstances where there is a high risk of phrenic nerve injury or in diseases affecting the contractility or the motion of the diaphragm such as neuro-muscular diseases. Recent methods such as speckle tracking imaging and ultrasound shear wave elastography should provide more detailed information for better assessment of diaphragmatic function.

• Ultrasound
• Hemidiaphragm
• Motion
• Thickness
• Paralysis
• Dysfunction
• Two-dimensional mode
• M-mode
• Speckle tracking imaging
• Ultrasound shear wave elastography

• Diaphragm ultrasound
• Intensive care unit (ICU)
• Mechanical ventilation
• Point of care ultrasound (POCUS)
• Respiratory failure