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Pulmonology 2019The diaphragm is the main breathing muscle and contraction of the diaphragm is vital for ventilation so any disease that interferes with diaphragmatic innervation,... (Comparative Study)
Comparative Study Review
The diaphragm is the main breathing muscle and contraction of the diaphragm is vital for ventilation so any disease that interferes with diaphragmatic innervation, contractile muscle function, or mechanical coupling to the chest wall can cause diaphragm dysfunction. Diaphragm dysfunction is associated with dyspnoea, intolerance to exercise, sleep disturbances, hypersomnia, with a potential impact on survival. Diagnosis of diaphragm dysfunction is based on static and dynamic imaging tests (especially ultrasound) and pulmonary function and phrenic nerve stimulation tests. Treatment will depend on the symptoms and causes of the disease. The management of diaphragm dysfunction may include observation in asymptomatic patients with unilateral dysfunction, surgery (i.e., plication of the diaphragm), placement of a diaphragmatic pacemaker or invasive and/or non-invasive mechanical ventilation in symptomatic patients with bilateral paralysis of the diaphragm. This type of patient should be treated in experienced centres. This review aims to provide an overview of the problem, with special emphasis on the diseases that cause diaphragmatic dysfunction and the diagnostic and therapeutic procedures most commonly employed in clinical practice. The ultimate goal is to establish a standard of care for diaphragmatic dysfunction.
Topics: Diaphragm; Diaphragmatic Eventration; Fluoroscopy; Humans; Microsurgery; Phrenic Nerve; Radiography; Respiration, Artificial; Respiratory Function Tests; Respiratory Paralysis; Transcutaneous Electric Nerve Stimulation; Ultrasonography
PubMed: 30509855
DOI: 10.1016/j.pulmoe.2018.10.008 -
Current Opinion in Critical Care Feb 2020To review the clinical problem of diaphragm function in critically ill patients and describes recent advances in bedside monitoring of diaphragm function. (Review)
Review
PURPOSE OF REVIEW
To review the clinical problem of diaphragm function in critically ill patients and describes recent advances in bedside monitoring of diaphragm function.
RECENT FINDINGS
Diaphragm weakness, a consequence of diaphragm dysfunction and atrophy, is common in the ICU and associated with serious clinical consequences. The use of ultrasound to assess diaphragm structure (thickness, thickening) and mobility (caudal displacement) appears to be feasible and reproducible, but no large-scale 'real-life' study is available. Diaphragm ultrasound can also be used to evaluate diaphragm muscle stiffness by means of shear-wave elastography and strain by means of speckle tracking, both of which are correlated with diaphragm function in healthy. Electrical activity of the diaphragm is correlated with diaphragm function during brief airway occlusion, but the repeatability of these measurements exhibits high within-subject variability.
SUMMARY
Mechanical ventilation is involved in the pathogenesis of diaphragm dysfunction, which is associated with severe adverse events. Although ultrasound and diaphragm electrical activity could facilitate monitoring of diaphragm function to deliver diaphragm-protective ventilation, no guidelines concerning the use of these modalities have yet been published. The weaning process, assessment of patient-ventilator synchrony and evaluation of diaphragm function may be the most clinically relevant indications for these techniques.
Topics: Critical Illness; Diaphragm; Humans; Intensive Care Units; Respiration, Artificial; Ultrasonography
PubMed: 31876624
DOI: 10.1097/MCC.0000000000000682 -
Jornal Brasileiro de Pneumologia :... 2020The diaphragm is the main muscle of respiration, acting continuously and uninterruptedly to sustain the task of breathing. Diaphragmatic dysfunction can occur secondary... (Review)
Review
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.
Topics: Diaphragm; Humans; Neuromuscular Diseases; Respiratory Muscles; Respiratory Tract Diseases; Ultrasonography
PubMed: 33237154
DOI: 10.36416/1806-3756/e20200064 -
Advances in Respiratory Medicine 2017The diaphragm is the primary muscle involved in active inspiration and serves also as an important anatomical landmark that separates the thoracic and abdominal cavity.... (Review)
Review
The diaphragm is the primary muscle involved in active inspiration and serves also as an important anatomical landmark that separates the thoracic and abdominal cavity. However, the diaphragm muscle like other structures and organs in the human body has more than one function, and displays many anatomic links throughout the body, thereby forming a 'network of breathing'. Besides respiratory function, it is important for postural control as it stabilises the lumbar spine during loading tasks. It also plays a vital role in the vascular and lymphatic systems, as well as, is greatly involved in gastroesophageal functions such as swallowing, vomiting, and contributing to the gastroesophageal reflux barrier. In this paper we set out in detail the anatomy and embryology of the diaphragm and attempt to show it serves as both: an important exchange point of information, originating in different areas of the body, and a source of information in itself. The study also discusses all of its functions related to breathing.
Topics: Diaphragm; Esophagogastric Junction; Humans; Posture; Respiratory Mechanics; Work of Breathing
PubMed: 28871591
DOI: 10.5603/ARM.2017.0037 -
BMC Pulmonary Medicine Mar 2021Diaphragm muscle dysfunction is increasingly recognized as an important element of several diseases including neuromuscular disease, chronic obstructive pulmonary... (Review)
Review
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.
Topics: Critical Illness; Diaphragm; Fluoroscopy; Humans; Magnetic Resonance Imaging; Radiography, Thoracic; Tomography, X-Ray Computed; Ultrasonography
PubMed: 33722215
DOI: 10.1186/s12890-021-01441-6 -
Physiology (Bethesda, Md.) Mar 2018Breathing occurs without thought but is controlled by a complex neural network with a final output of phrenic motor neurons activating diaphragm muscle fibers (i.e.,... (Review)
Review
Breathing occurs without thought but is controlled by a complex neural network with a final output of phrenic motor neurons activating diaphragm muscle fibers (i.e., motor units). This review considers diaphragm motor unit organization and how they are controlled during breathing as well as during expulsive behaviors.
Topics: Animals; Diaphragm; Humans; Motor Neurons; Recruitment, Neurophysiological; Respiration
PubMed: 29412056
DOI: 10.1152/physiol.00002.2018 -
Journal of Osteopathic Medicine Sep 2021Cardiac surgery with median sternotomy causes iatrogenic damage to the function of the diaphragm muscle that is both temporary and permanent. Myocardial infarction... (Review)
Review
Cardiac surgery with median sternotomy causes iatrogenic damage to the function of the diaphragm muscle that is both temporary and permanent. Myocardial infarction itself causes diaphragmatic genetic alterations, which lead the muscle to nonphysiological adaptation. The respiratory muscle area plays several roles in maintaining both physical and mental health, as well as in maximizing recovery after a cardiac event. The evaluation of the diaphragm is a fundamental step in the therapeutic process, including the use of instruments such as ultrasound, magnetic resonance imaging (MRI), and computed axial tomography (CT). This article reviews the neurophysiological relationships of the diaphragm muscle and the symptoms of diaphragmatic contractile dysfunction. The authors discuss a scientific basis for the use of a new noninstrumental diaphragmatic test in the hope of stimulating research.
Topics: Diaphragm; Humans; Phrenic Nerve; Respiratory Muscles; Respiratory Paralysis; Ultrasonography
PubMed: 34523291
DOI: 10.1515/jom-2021-0101 -
Intensive Care Medicine Apr 2020Respiratory muscle ultrasound is used to evaluate the anatomy and function of the respiratory muscle pump. It is a safe, repeatable, accurate, and non-invasive bedside... (Review)
Review
Respiratory muscle ultrasound is used to evaluate the anatomy and function of the respiratory muscle pump. It is a safe, repeatable, accurate, and non-invasive bedside technique that can be successfully applied in different settings, including general intensive care and the emergency department. Mastery of this technique allows the intensivist to rapidly diagnose and assess respiratory muscle dysfunction in critically ill patients and in patients with unexplained dyspnea. Furthermore, it can be used to assess patient-ventilator interaction and weaning failure in critically ill patients. This paper provides an overview of the basic and advanced principles underlying respiratory muscle ultrasound with an emphasis on the diaphragm. We review different ultrasound techniques useful for monitoring of the respiratory muscle pump and possible therapeutic consequences. Ideally, respiratory muscle ultrasound is used in conjunction with other components of critical care ultrasound to obtain a comprehensive evaluation of the critically ill patient. We propose the ABCDE-ultrasound approach, a systematic ultrasound evaluation of the heart, lungs and respiratory muscle pump, in patients with weaning failure.
Topics: Critical Care; Critical Illness; Diaphragm; Humans; Intensive Care Units; Respiratory Muscles; Ultrasonography
PubMed: 31938825
DOI: 10.1007/s00134-019-05892-8 -
American Journal of Respiratory and... May 2023Diaphragm neurostimulation consists of placing electrodes directly on or in proximity to the phrenic nerve(s) to elicit diaphragmatic contractions. Since its initial... (Review)
Review
Diaphragm neurostimulation consists of placing electrodes directly on or in proximity to the phrenic nerve(s) to elicit diaphragmatic contractions. Since its initial description in the 18th century, indications have shifted from cardiopulmonary resuscitation to long-term ventilatory support. Recently, the technical development of devices for temporary diaphragm neurostimulation has opened up the possibility of a new era for the management of mechanically ventilated patients. Combining positive pressure ventilation with diaphragm neurostimulation offers a potentially promising new approach to the delivery of mechanical ventilation which may benefit multiple organ systems. Maintaining diaphragm contractions during ventilation may attenuate diaphragm atrophy and accelerate weaning from mechanical ventilation. Preventing atelectasis and preserving lung volume can reduce lung stress and strain and improve homogeneity of ventilation, potentially mitigating ventilator-induced lung injury. Furthermore, restoring the thoracoabdominal pressure gradient generated by diaphragm contractions may attenuate the drop in cardiac output induced by positive pressure ventilation. Experimental evidence suggests diaphragm neurostimulation may prevent neuroinflammation associated with mechanical ventilation. This review describes the historical development and evolving approaches to diaphragm neurostimulation during mechanical ventilation and surveys the potential mechanisms of benefit. The review proposes a research agenda and offers perspectives for the future of diaphragm neurostimulation assisted mechanical ventilation for critically ill patients.
Topics: Humans; Respiration, Artificial; Diaphragm; Critical Illness; Positive-Pressure Respiration; Respiration
PubMed: 36917765
DOI: 10.1164/rccm.202212-2252CP -
BMC Pulmonary Medicine Mar 2021Prolonged mechanical ventilation (MV) induces diaphragm dysfunction in patients in the intensive care units (ICUs). Our study aimed to explore the therapeutic efficacy... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Prolonged mechanical ventilation (MV) induces diaphragm dysfunction in patients in the intensive care units (ICUs). Our study aimed to explore the therapeutic efficacy of early rehabilitation therapy in patients with prolonged MV in the ICU.
METHODS
Eighty eligible patients who underwent MV for > 72 h in the ICU from June 2019 to March 2020 were enrolled in this prospective randomised controlled trial. The patients were randomly divided into a rehabilitation group (n = 39) and a control group (n = 41). Rehabilitation therapy included six levels of rehabilitation exercises. Diaphragm function was determined using ultrasound (US).
RESULTS
Diaphragmatic excursion (DE) and diaphragm thickening fraction (DTF) were significantly decreased in all patients in both groups after prolonged MV (p < 0.001). The rehabilitation group had significantly higher DTF (p = 0.008) and a smaller decrease in DTF (p = 0.026) than the control group after 3 days of rehabilitation training. The ventilator duration and intubation duration were significantly shorter in the rehabilitation group than in the control group (p = 0.045 and p = 0.037, respectively). There were no significant differences in the duration of ICU stay, proportion of patients undergoing tracheotomy, and proportion of recovered patients between the two groups.
CONCLUSIONS
Early rehabilitation is feasible and beneficial to ameliorate diaphragm dysfunction induced by prolonged MV and advance withdrawal from the ventilator and extubation in patients with MV. Diaphragm US is suggested for mechanically ventilated patients in the ICU. Trial registration Chinese Clinical Trial Registry, ID: ChiCTR1900024046, registered on 2019/06/23.
Topics: Adult; Aged; Diaphragm; Exercise Therapy; Female; Humans; Intensive Care Units; Male; Middle Aged; Muscular Atrophy; Prospective Studies; Respiration, Artificial; Time Factors; Ultrasonography; Ventilator Weaning
PubMed: 33781259
DOI: 10.1186/s12890-021-01461-2