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Critical Care (London, England) Jul 2023This narrative review explores the physiology and evidence-based management of patients with severe acute respiratory distress syndrome (ARDS) and refractory hypoxemia,... (Review)
Review
This narrative review explores the physiology and evidence-based management of patients with severe acute respiratory distress syndrome (ARDS) and refractory hypoxemia, with a focus on mechanical ventilation, adjunctive therapies, and veno-venous extracorporeal membrane oxygenation (V-V ECMO). Severe ARDS cases increased dramatically worldwide during the Covid-19 pandemic and carry a high mortality. The mainstay of treatment to improve survival and ventilator-free days is proning, conservative fluid management, and lung protective ventilation. Ventilator settings should be individualized when possible to improve patient-ventilator synchrony and reduce ventilator-induced lung injury (VILI). Positive end-expiratory pressure can be individualized by titrating to best respiratory system compliance, or by using advanced methods, such as electrical impedance tomography or esophageal manometry. Adjustments to mitigate high driving pressure and mechanical power, two possible drivers of VILI, may be further beneficial. In patients with refractory hypoxemia, salvage modes of ventilation such as high frequency oscillatory ventilation and airway pressure release ventilation are additional options that may be appropriate in select patients. Adjunctive therapies also may be applied judiciously, such as recruitment maneuvers, inhaled pulmonary vasodilators, neuromuscular blockers, or glucocorticoids, and may improve oxygenation, but do not clearly reduce mortality. In select, refractory cases, the addition of V-V ECMO improves gas exchange and modestly improves survival by allowing for lung rest. In addition to VILI, patients with severe ARDS are at risk for complications including acute cor pulmonale, physical debility, and neurocognitive deficits. Even among the most severe cases, ARDS is a heterogeneous disease, and future studies are needed to identify ARDS subgroups to individualize therapies and advance care.
Topics: Humans; Pandemics; COVID-19; Respiration, Artificial; Respiratory Distress Syndrome; Continuous Positive Airway Pressure; Ventilator-Induced Lung Injury; Hypoxia
PubMed: 37464381
DOI: 10.1186/s13054-023-04572-w -
European Respiratory Review : An... Jun 2023There is a well-recognised importance for personalising mechanical ventilation settings to protect the lungs and the diaphragm for each individual patient. Measurement... (Review)
Review
There is a well-recognised importance for personalising mechanical ventilation settings to protect the lungs and the diaphragm for each individual patient. Measurement of oesophageal pressure ( ) as an estimate of pleural pressure allows assessment of partitioned respiratory mechanics and quantification of lung stress, which helps our understanding of the patient's respiratory physiology and could guide individualisation of ventilator settings. Oesophageal manometry also allows breathing effort quantification, which could contribute to improving settings during assisted ventilation and mechanical ventilation weaning. In parallel with technological improvements, monitoring is now available for daily clinical practice. This review provides a fundamental understanding of the relevant physiological concepts that can be assessed using measurements, both during spontaneous breathing and mechanical ventilation. We also present a practical approach for implementing oesophageal manometry at the bedside. While more clinical data are awaited to confirm the benefits of -guided mechanical ventilation and to determine optimal targets under different conditions, we discuss potential practical approaches, including positive end-expiratory pressure setting in controlled ventilation and assessment of inspiratory effort during assisted modes.
Topics: Humans; Respiration, Artificial; Lung; Respiratory Mechanics; Ventilators, Mechanical; Monitoring, Physiologic
PubMed: 37197768
DOI: 10.1183/16000617.0186-2022 -
Journal of Clinical Medicine Jan 2024Diaphragm Dysfunction (DD) is a respiratory disorder with multiple causes. Although both unilateral and bilateral DD could ultimately lead to respiratory failure, the... (Review)
Review
Diaphragm Dysfunction (DD) is a respiratory disorder with multiple causes. Although both unilateral and bilateral DD could ultimately lead to respiratory failure, the former is more common. Increasing research has recently delved into perioperative diaphragm protection. It has been established that DD promotes atelectasis development by affecting lung and chest wall mechanics. Diaphragm function must be specifically assessed for clinicians to optimally select an anesthetic approach, prepare for adequate monitoring, and implement the perioperative plan. Recent technological advancements, including dynamic MRI, ultrasound, and esophageal manometry, have critically aided disease diagnosis and management. In this context, it is noteworthy that therapeutic approaches for DD vary depending on its etiology and include various interventions, either noninvasive or invasive, aimed at promoting diaphragm recruitment. This review aims to unravel alternative anesthetic and operative strategies that minimize postoperative dysfunction by elucidating the identification of patients at a higher risk of DD and procedures that could cause postoperative DD, facilitating the recognition and avoidance of anesthetic and surgical interventions likely to impair diaphragmatic function.
PubMed: 38256653
DOI: 10.3390/jcm13020519 -
Clinical Endoscopy Sep 2023Achalasia is an esophageal motility disorder characterized by impaired lower esophageal sphincter relaxation and peristalsis of the esophageal body. With the increasing... (Review)
Review
Achalasia is an esophageal motility disorder characterized by impaired lower esophageal sphincter relaxation and peristalsis of the esophageal body. With the increasing prevalence of achalasia, interest in the role of endoscopy in its diagnosis, treatment, and monitoring is also growing. The major diagnostic modalities for achalasia include high-resolution manometry, esophagogastroduodenoscopy, and barium esophagography. Endoscopic assessment is important for early diagnosis to rule out diseases that mimic achalasia symptoms, such as pseudo-achalasia, esophageal cancer, esophageal webs, and eosinophilic esophagitis. The major endoscopic characteristics suggestive of achalasia include a widened esophageal lumen and food residue in the esophagus. Once diagnosed, achalasia can be treated either endoscopically or surgically. The preference for endoscopic treatment is increasing owing to its minimal invasiveness. Botulinum toxins, pneumatic balloon dilation, and peroral endoscopic myotomy (POEM) are important endoscopic treatments. Previous studies have demonstrated excellent treatment outcomes for POEM, with >95% improvement in dysphagia, making POEM the mainstay treatment option for achalasia. Several studies have reported an increased risk of esophageal cancer in patients with achalasia. However, routine endoscopic surveillance remains controversial owing to the lack of sufficient data. Further studies on surveillance methods and duration are warranted to establish concordant guidelines for the endoscopic surveillance of achalasia.
PubMed: 37430397
DOI: 10.5946/ce.2023.001 -
Frontiers in Physiology 2023A rhythmic expression of clock genes occurs within the cells of multiple organs and tissues throughout the body, termed "peripheral clocks." Peripheral clocks are... (Review)
Review
A rhythmic expression of clock genes occurs within the cells of multiple organs and tissues throughout the body, termed "peripheral clocks." Peripheral clocks are subject to entrainment by a multitude of factors, many of which are directly or indirectly controlled by the light-entrainable clock located in the suprachiasmatic nucleus of the hypothalamus. Peripheral clocks occur in the gastrointestinal tract, notably the epithelia whose functions include regulation of absorption, permeability, and secretion of hormones; and in the myenteric plexus, which is the intrinsic neural network principally responsible for the coordination of muscular activity in the gut. This review focuses on the physiological circadian variation of major colonic functions and their entraining mechanisms, including colonic motility, absorption, hormone secretion, permeability, and pain signalling. Pathophysiological states such as irritable bowel syndrome and ulcerative colitis and their interactions with circadian rhythmicity are also described. Finally, the classic circadian hormone melatonin is discussed, which is expressed in the gut in greater quantities than the pineal gland, and whose exogenous use has been of therapeutic interest in treating colonic pathophysiological states, including those exacerbated by chronic circadian disruption.
PubMed: 37711458
DOI: 10.3389/fphys.2023.1239278 -
Digestion 2024Functional endoscopy signifies a significant advancement in gastrointestinal examination, integrating motor function assessments alongside routine endoscopy findings.... (Review)
Review
BACKGROUND
Functional endoscopy signifies a significant advancement in gastrointestinal examination, integrating motor function assessments alongside routine endoscopy findings. Traditional gastrointestinal endoscopy primarily focuses on the detection of early-stage cancer by identifying morphological changes within the gastrointestinal tract. These alterations include modifications in lumen structure, color tone, and surface patterns, which can be diagnosed using endoscopic images that assess these morphological changes. In contrast, functional endoscopy aims to dynamically evaluate the peristaltic movements of the digestive tract and the presence or movement of reflux of digestive fluids during the endoscopic procedure. It also seeks to identify morphological changes such as hiatal hernias, as observed in conventional endoscopy. Consequently, relying solely on endoscopic images proves inadequate for diagnosis, necessitating continuous observation of these dynamic movements.
SUMMARY
The endoscopic pressure study integrated system (EPSIS) serves as an exemplar of functional endoscopy. It incorporates a stress test to assess the functionality of the lower esophageal sphincter (LES) through intragastric insufflation. A crucial element of EPSIS evaluation is the identification of the scope holding sign (SHS), which signifies LES contraction. EPSIS also encompasses the observation of esophageal peristaltic waves and the auditory detection of burping, providing a comprehensive diagnostic approach while observing the sphincter from a retroflex view on the stomach side. By integrating these dynamic findings, functional endoscopy offers an efficient method for diagnosing functional gastrointestinal diseases, such as gastroesophageal reflux disease (GERD).
KEY MESSAGES
Functional endoscopy combines motor function assessments with traditional endoscopy, enhancing the diagnostic capabilities of gastrointestinal examinations. Traditional endoscopy focuses on identifying morphological changes, while functional endoscopy evaluates dynamic movements, reflux, and sphincter functionality. EPSIS exemplifies functional endoscopy, featuring a stress test and the SHS for LES contraction assessment. EPSIS provides a comprehensive approach to diagnose GERD by integrating dynamic observations.
Topics: Humans; Gastroesophageal Reflux; Endoscopy, Gastrointestinal; Esophageal Sphincter, Lower; Hernia, Hiatal; Manometry
PubMed: 38008079
DOI: 10.1159/000534831 -
Cureus Jul 2023Distal esophageal spasm is characterized by premature contractions of the distal esophageal smooth muscle leading to non-obstructive dysphagia and non-cardiac chest... (Review)
Review
Distal esophageal spasm is characterized by premature contractions of the distal esophageal smooth muscle leading to non-obstructive dysphagia and non-cardiac chest pain. Diagnosis requires the presence of symptoms along with evidence of at least 20% premature contractions in the setting of a normal lower esophageal sphincter relaxation on high-resolution manometry. New updates to the Chicago Classification have improved the diagnostic accuracy of this method. Functional lumen imaging probe is a growing diagnostic modality that gives a more complete picture of esophageal motility. Pharmacologic treatment remains inadequate. Endoscopic myotomy might be of benefit for non-achalasia esophageal motility disorders. More research is required to better understand the pathophysiology and develop safe and long-lasting management for this disease.
PubMed: 37551217
DOI: 10.7759/cureus.41504