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Journal of Thoracic Imaging Jul 2019The diaphragm is an inconspicuous fibromuscular septum, and disorders may result in respiratory impairment and morbidity and mortality when untreated. Radiologists need... (Review)
Review
The diaphragm is an inconspicuous fibromuscular septum, and disorders may result in respiratory impairment and morbidity and mortality when untreated. Radiologists need to accurately diagnose diaphragmatic disorders, understand the surgical approaches to diaphragmatic incisions/repairs, and recognize postoperative changes and complications. Diaphragmatic defects violate the boundary between the chest and abdomen, with the risk of herniation and strangulation of abdominal contents. In our surgical practice, patients with diaphragmatic hernias present acutely with incarceration and/or strangulation. Bochdalek hernias are commonly diagnosed in asymptomatic older adults on computed tomography; however, when viscera or a large amount of fat herniates into the chest, surgical intervention is strongly advocated. Morgagni hernias are rare in adults and typically manifest acutely with bowel obstruction. Patients with traumatic diaphragm injury may have an acute, latent, or delayed presentation, and radiologists should be vigilant in inspecting the diaphragm on the initial and all subsequent thoracoabdominal imaging studies. Almost all traumatic diaphragm injury are surgically repaired. Finally, with porous diaphragm syndrome, fluid, air, and tissue from the abdomen may communicate with the pleural space through diaphragmatic fenestrations and result in a catamenial pneumothorax or large pleural effusion. When the underlying disorder cannot be effectively treated, the goal of surgical intervention is to establish the diagnosis, incite pleural adhesions, and close diaphragmatic defects. Diaphragmatic plication may be helpful in patients with eventration or acquired injuries of the phrenic nerve, as it can stabilize the affected diaphragm. Phrenic nerve pacing may improve respiratory function in select patients with high cervical cord injury or central hypoventilation syndrome.
Topics: Diaphragm; Hernia, Diaphragmatic; Humans; Tomography, X-Ray Computed
PubMed: 31206456
DOI: 10.1097/RTI.0000000000000416 -
Annals of Anatomy = Anatomischer... May 2016The diaphragm is a respiratory muscle that is primarily responsible for the respiratory function in normal individuals. In mammals, the diaphragm muscle has been studied... (Review)
Review
The diaphragm is a respiratory muscle that is primarily responsible for the respiratory function in normal individuals. In mammals, the diaphragm muscle has been studied from the early days of zoology, comparative and experimental anatomy, physiology, medicine, physics, and philosophy. However, even with these early advances in knowledge pertaining to the diaphragm, comprehensive morphological data on the diaphragm are still incomplete. In this review, we summarize the beginnings of the morphological description of the diaphragm, and we describe the current status of the known morphological and embryological features. In addition, we correlate how the impairment of the diaphragm muscle in Duchenne muscular dystrophy (DMD) can lead to patient deaths. DMD is the most common X-linked muscle degenerative disease and is caused by a lack of dystrophin protein. Dystrophin is an important muscle protein that links the cellular cytoskeleton with the extracellular matrix. In the absence of dystrophin, the muscle becomes susceptible to damage during muscle contraction. This review allows researchers to obtain an overview of the diaphragm, transcending the morphological data from animals described in conventional literature.
Topics: Animals; Diaphragm; Humans; Respiratory Mechanics; Species Specificity
PubMed: 27045597
DOI: 10.1016/j.aanat.2016.03.008 -
Journal of Muscle Research and Cell... Dec 2017The diaphragm is the "respiratory pump;" the muscle that generates pressure to allow ventilation. Diaphragm muscles play a vital function and thus are subjected to... (Review)
Review
The diaphragm is the "respiratory pump;" the muscle that generates pressure to allow ventilation. Diaphragm muscles play a vital function and thus are subjected to continuous mechanical loading. One of its peculiarities is the ability to generate distinct mechanical and biochemical responses depending on the direction through which the mechanical forces applied to it. Contractile forces originated from its contractile components are transmitted to other structural components of its muscle fibers and the surrounding connective tissue. The anisotropic mechanical properties of the diaphragm are translated into biochemical signals that are directionally mechanosensitive by mechanisms that appear to be unique to this muscle. Here, we reviewed the current state of knowledge on the biochemical pathways regulated by mechanical signals emphasizing their anisotropic behavior in the normal diaphragm and analyzed how they are affected in muscular dystrophies.
Topics: Animals; Diaphragm; Humans; Muscle Contraction; Muscle Strength; Muscular Dystrophies
PubMed: 28986699
DOI: 10.1007/s10974-017-9483-7 -
Medicina (Kaunas, Lithuania) May 2023: Common problems in people with COVID-19 include decreased respiratory strength and function. We investigated the effects of (TMRT) and lower limb ergometer (LE)... (Randomized Controlled Trial)
Randomized Controlled Trial
: Common problems in people with COVID-19 include decreased respiratory strength and function. We investigated the effects of (TMRT) and lower limb ergometer (LE) training on diaphragm thickness and respiratory function in patients with a history of COVID-19. : In total, 30 patients were randomly divided into a TMRT training group and an LE training group. The TMRT group performed thoracic mobilization and respiratory muscle endurance training for 30 min three times a week for 8 weeks. The LE group performed lower limb ergometer training for 30 min three times a week for 8 weeks. The participants' diaphragm thickness was measured via rehabilitative ultrasound image (RUSI) and a respiratory function test was conducted using a MicroQuark spirometer. These parameters were measured before the intervention and 8 weeks after the intervention. : There was a significant difference ( < 0.05) between the results obtained before and after training in both groups. Right diaphragm thickness at rest, diaphragm thickness during contraction, and respiratory function were significantly more improved in the TMRT group than in the LE group ( < 0.05). : In this study, we confirmed the effects of TMRT training on diaphragm thickness and respiratory function in patients with a history of COVID-19.
Topics: Humans; Diaphragm; Respiratory Muscles; Endurance Training; COVID-19; Respiration; Muscle Strength
PubMed: 37241138
DOI: 10.3390/medicina59050906 -
Journal of Cardiothoracic and Vascular... Sep 2019Of the various muscles that make up the respiratory system, the diaphragm is the prima donna. In the past, only specialist research centers were able to estimate and... (Review)
Review
Of the various muscles that make up the respiratory system, the diaphragm is the prima donna. In the past, only specialist research centers were able to estimate and challenge the effort of this muscle; this was achieved by measuring transdiaphragmatic pressure-an invasive technique involving a double-balloon probe inserted through the esophagus-or by measuring twitch pressure (ie, the pressure generated at the outside tip of the endotracheal tube). However, the prevalence of diaphragm dysfunction in critically ill patients requiring intubation can exceed 60% (at the time of hospital admission) and may rise to as high as 80% in patients requiring prolonged mechanical ventilation and experiencing difficult weaning. Although still in its infancy, modern ultrasound (US) provides a fascinating way to study the diaphragm, permitting the assessment of its excursion, thickness, and thickening. Furthermore, US enables the course of diaphragmatic function to be followed on a day-to-day basis, from intensive care admission to discharge, and it can help us understand the different causes of underlying disease: trauma, infection (eg, sepsis-induced diaphragm dysfunction), cancer, weaning problems (eg, ventilation-induced diaphragm dysfunction), etc. Today, the assessment of diaphragm dysfunction with US provides an important first step toward improving the detection of diaphragm dysfunction and as a protective and supportive strategy for its management. The purposes of this review are as follows: (1) to explore which US method is best for evaluating diaphragm function in the intensive care unit and how and when it should be used, and (2) to discuss which diseases may involve the diaphragm, and what therapies should be used.
Topics: Critical Care; Diaphragm; Humans; Ultrasonography, Interventional
PubMed: 30686657
DOI: 10.1053/j.jvca.2019.01.003 -
Biomedical Engineering Online Jan 2023Every year, more than 2.5 million critically ill patients in the ICU are dependent on mechanical ventilation. The positive pressure in the lungs generated by the...
BACKGROUND
Every year, more than 2.5 million critically ill patients in the ICU are dependent on mechanical ventilation. The positive pressure in the lungs generated by the ventilator keeps the diaphragm passive, which can lead to a loss of myofibers within a short time. To prevent ventilator-induced diaphragmatic dysfunction (VIDD), phrenic nerve stimulation may be used.
OBJECTIVE
The goal of this study is to show the feasibility of transesophageal phrenic nerve stimulation (TEPNS). We hypothesize that selective phrenic nerve stimulation can efficiently activate the diaphragm with reduced co-stimulations.
METHODS
An in vitro study in saline solution combined with anatomical findings was performed to investigate relevant stimulation parameters such as inter-electrode spacing, range to target site, or omnidirectional vs. sectioned electrodes. Subsequently, dedicated esophageal electrodes were inserted into a pig and single stimulation pulses were delivered simultaneously with mechanical ventilation. Various stimulation sites and response parameters such as transdiaphragmatic pressure or airway flow were analyzed to establish an appropriate stimulation setting.
RESULTS
Phrenic nerve stimulation with esophageal electrodes has been demonstrated. With a current amplitude of 40 mA, similar response figures of the diaphragm activation as compared to conventional stimulation with needle electrodes at 10mA were observed. Directed electrodes best aligned with the phrenic nerve resulted in up to 16.9 % higher amplitude at the target site in vitro and up to 6 cmH20 higher transdiaphragmatic pressure in vivo as compared to omnidirectional electrodes. The activation efficiency was more sensitive to the stimulation level inside the esophagus than to the inter-electrode spacing. Most effective and selective stimulation was achieved at the level of rib 1 using sectioned electrodes 40 mm apart.
CONCLUSION
Directed transesophageal phrenic nerve stimulation with single stimuli enabled diaphragm activation. In the future, this method might keep the diaphragm active during, and even support, artificial ventilation. Meanwhile, dedicated sectioned electrodes could be integrated into gastric feeding tubes.
Topics: Animals; Swine; Phrenic Nerve; Feasibility Studies; Diaphragm; Respiration, Artificial; Electrodes; Electric Stimulation
PubMed: 36717872
DOI: 10.1186/s12938-023-01071-5 -
Current Problems in Diagnostic Radiology 2015The thoracoabdominal region consists of the inferior thorax and superior abdomen and is separated by the diaphragm. Although the diaphragm appears to act as a barrier in... (Review)
Review
The thoracoabdominal region consists of the inferior thorax and superior abdomen and is separated by the diaphragm. Although the diaphragm appears to act as a barrier in this region, various lesions can straddle across the diaphragm and lie contiguously in both the thorax and the abdomen. Thoracoabdominal lesions can extend across the diaphragm either through its various natural openings or through abnormal defects. The natural openings lie in the midline and include the hiatuses for the inferior vena cava, the esophagus, and the retrocrural space, which includes the aortic hiatus and the prevertebral and paravertebral spaces. Abnormal defects include congenital defects in fusion, that is, foramina of Morgagni and Bochdalek and acquired diaphragmatic rupture. Very large lesions can also displace the diaphragm, either inferiorly or superiorly, and thus appear to pseudoextend across this region. Using a pattern approach based on the location and route of extension, thoracoabdominal lesions can be classified as central and lateral lesions. Central lesions form a large group, and based on their location, they can be further classified as central anterior, central tendon, inferior vena cava, esophageal, and retrocrural pathologies. Both central and lateral thoracoabdominal lesions form a diverse spectrum and can be congenital, neoplastic, inflammatory, iatrogenic, or traumatic in etiology. Morphologically, these can consist of solid masses, cystic lesions, and ill-defined collections extending across the diaphragm. This article depicts the imaging appearance of the wide spectrum of lesions straddling across the diaphragm. Familiarity with these pathologies can help in better understanding the continuum formed by the thoracoabdominal region and the various routes of transdiaphragmatic extension.
Topics: Abdomen; Abdominal Neoplasms; Diaphragm; Humans; Magnetic Resonance Imaging; Radiography, Abdominal; Thoracic Neoplasms; Thorax; Tomography, X-Ray Computed
PubMed: 25795032
DOI: 10.1067/j.cpradiol.2014.11.005 -
Journal of the American College of... Oct 2022In addition to the diaphragm's role as the primary respiratory muscle, it also plays an under-recognized role in cardiac function. It serves as a pump facilitating... (Review)
Review
In addition to the diaphragm's role as the primary respiratory muscle, it also plays an under-recognized role in cardiac function. It serves as a pump facilitating venous and lymph return, modulating left ventricular afterload hemodynamics and pericardial pressures, as well as regulating autonomic tone. Heart failure (HF) is associated with diaphragmatic changes (ie, muscle fiber atrophy and weakness, increased ratio of type I to type II muscle fibers, and altered muscle metaboreflex) that lead to diaphragmatic dysfunction with subsequent symptomatic manifestations of HF. Herein, it is proposed that targeting the diaphragm in patients with HF via inspiratory muscle training or device-based stimulation can provide a novel treatment pathway for HF. Reviewed are several potential mechanisms through which therapies targeting the diaphragm can be beneficial in HF (ie, improving preload reserve, atrial and ventricular synchrony, and metaboreflex activity; reducing pericardial restraint; and restoring diaphragm strength).
Topics: Humans; Diaphragm; Cardiovascular Diseases; Heart Failure; Hemodynamics
PubMed: 36265961
DOI: 10.1016/j.jacc.2022.08.760 -
La Revue Du Praticien Apr 2018Long-acting reversible contraception. Long-acting reversible contraception (LARC) have a long-prolonged efficacy over 3 to 5 years depending on the method. They have...
Long-acting reversible contraception. Long-acting reversible contraception (LARC) have a long-prolonged efficacy over 3 to 5 years depending on the method. They have become in recent years a subject of major interest in contraception. Indeed, these contraceptive methods, including intrauterine devices and the subcutaneous implant, allow obtaining an optimal contraceptive effectiveness while reducing the constraints for the women. All these contraceptions require the participation of an experienced professional for their placement and withdrawal. These LARCs may usually be suitable for all women after removal of rare contraindications. For each LARC, the potential advantages and disadvantages must be taken into account in order to choose the most appropriate method for each woman. Regular monitoring is always required to allow premature withdrawal in case of side effects, incident or wish to pregnancy. Their reversibility is immediate.
Topics: Contraception; Contraceptive Agents, Female; Female; Humans; Intrauterine Devices; Long-Acting Reversible Contraception; Pregnancy
PubMed: 30869384
DOI: No ID Found -
Current Opinion in Critical Care Feb 2016The purpose of the review is to summarize and discuss recent research regarding the role of mechanical ventilation in producing weakness and atrophy of the diaphragm in... (Review)
Review
PURPOSE OF REVIEW
The purpose of the review is to summarize and discuss recent research regarding the role of mechanical ventilation in producing weakness and atrophy of the diaphragm in critically ill patients, an entity termed ventilator-induced diaphragmatic dysfunction (VIDD).
RECENT FINDINGS
Severe weakness of the diaphragm is frequent in mechanically ventilated patients, in whom it contributes to poor outcomes including increased mortality. Significant progress has been made in identifying the molecular mechanisms responsible for VIDD in animal models, and there is accumulating evidence for occurrence of the same cellular processes in the diaphragms of human patients undergoing prolonged mechanical ventilation.
SUMMARY
Recent research is pointing the way to novel pharmacologic therapies as well as nonpharmacologic methods for preventing VIDD. The next major challenge in the field will be to move these findings from the bench to the bedside in critically ill patients.
Topics: Animals; Critical Care; Critical Illness; Diaphragm; Female; Follow-Up Studies; Humans; Intensive Care Units; Male; Muscle Weakness; Respiration, Artificial; Respiratory Insufficiency; Respiratory Paralysis; Risk Assessment; Time Factors; Treatment Outcome
PubMed: 26627540
DOI: 10.1097/MCC.0000000000000272