Mediastinum (Hong Kong, China)最新文献

Anesthesia management of patients with mediastinal mass compressing the central airway is considered challenging. It is widely believed that general anesthesia induction in patients with mediastinal mass is associated with airway collapse, difficulty in ventilation and hemodynamic compromise. Additionally, several case reports and case series described patients demise after induction of general anesthesia. This has led to the strong recommendations to use inhalation induction, avoid the use of muscle relaxant and maintenance of spontaneous ventilation. Recent studies shed new light on our understanding of airway changes associated with mediastinal mass by directly visualizing and measuring the actual changes of the airway caliber and the variation in the peak inspiratory flow (PIF) and peak expiratory flow (PEF) in patients with mediastinal mass. These studies describe the changes in airway mechanics in different states e.g., awake and anesthetized, spontaneous and positive pressure ventilated with or without muscle relaxation. Interesting new findings in these recent publications show that general anesthesia with and without muscle relaxation does not worsen a pre-existing narrowing of the airway compressed by mediastinal mass. Moreover, it was discovered that the addition of positive pressure ventilation, positive end-expiratory pressure (PEEP) and muscle relaxation in an anesthetized patient were associated with improvement in the airway caliber and airflow in these patient's population. This new understanding of the mechanics of airway obstruction and the effects of anesthesia and mechanical ventilation on patients with mediastinal mass challenges our current anesthesia practices and leads us to consider a new approach to anesthetize and ventilate these patients. This article will review the past literature that led to the widely practiced current anesthesia techniques and how it is challenged with the new research. The author will also provide a new perspective and anesthesia technique that align with the new research findings for safe induction and maintenance of general anesthesia in patients with mediastinal mass.

Background: In mediastinal biopsies that show fibrosis, the differential diagnosis includes fibrosing mediastinitis, immunoglobulin G subclass 4-related disease, Hodgkin lymphoma, as well as reactive fibrotic and inflammatory changes adjacent to other processes including neoplasms.

Cases description: We report two cases of incidentally detected mediastinal seminoma that contained extensive areas of paucicellular fibrosis, which precluded accurate preoperative biopsy diagnosis. The fibrosis consisted of mildly inflamed, densely scarred tissue with thin dilated vessels, and was present to a significant extent that is suggestive of spontaneous regression. These features are not currently described in the World Health Organization Classification of Thoracic Tumors. In both patients, needle and open biopsies sampled only the fibrotic areas of the tumors, and the final diagnosis was not achieved until surgical excision was performed. After surgery, both patients received chemotherapy, and were alive without evidence of disease at 3.4 years and 1 year post-operatively, respectively. Tumor fibrosis composed approximately 95% and 50% of each patient's tumor, respectively. In one of the patients, correlation of the needle biopsy position with the positron emission tomography (PET) scan revealed that the biopsy needle had sampled a non-metabolically active portion of the tumor.

Conclusions: While pathologic spontaneous regression is well-described in gonadal germ cell tumors, it is not well-reported in extragonadal locations. Prospective knowledge of this diagnostic pitfall and targeting PET-avid regions of the tumor may increase the diagnostic yield and help to avoid non-indicated surgical interventions.

Mediastinal tumors are a remarkably diverse category. They include malignant and benign forms with different rates of disease progression and tissue invasion. Anesthesiologists may encounter significant difficulties in managing patients with giant mediastinal tumors due to the non-negligible occurrence of severe cardiorespiratory collapse. Respiratory complications ensue from the compression of the airways induced by the mediastinal mass: the compressive effects may be exacerbated by positioning or anesthesia induction. Furthermore, the compression or invasion of major vessels may elicit acute cardiovascular collapse. The specter of sudden cardiorespiratory deterioration should lead the anesthesiologist to careful planning: acknowledging clinical and radiological signs that may presage an increased risk of life-threatening complications is of pivotal importance. This review aims to present a strategy for treating patients with mediastinal masses, starting with the pathophysiological elements and moving through preoperative care, intraoperative behavior, and the recovery period. We will also focus on respiratory and cardiovascular issues, emphasizing the need for extracorporeal membrane oxygenation (ECMO) as a rescue and crucial component of the anesthesia strategy. Understanding the physiological alterations after anesthesia induction can aid in identifying and treating potential problems. In addition, we attempted to offer insight into multimodal anesthesia and analgesia management: we emphasize the importance of a thorough preoperative assessment and the need for reviewing extracorporeal support not just a resuscitative strategy but as an integrated component of the perioperative care.

Background and objective: Bronchogenic cysts represent a rare form of cystic malformation of the respiratory tract. Primarily located in the mediastinum if occurring early in gestation as opposed to the thoracic cavity if arising later in development. However, they can arise from any site along the foregut. They exhibit a variety of clinical and radiologic presentations, representing a diagnostic challenge, especially in areas with endemic hydatid disease. Endoscopic drainage has emerged as a diagnostic and potentially therapeutic option but has been complicated by reports of infection. Surgical excision remains the standard of care allowing for symptomatic resolution and definitive diagnosis via pathologic examination; minimally invasive approaches such as robotic and thoracoscopic approaches aiding treatment. Following complete resection, prognosis is excellent with essentially no recurrence.

Methods: A review of the available electronic literature was performed from 1975 through 2022, using PubMed and Google Scholar, with an emphasis on more recent series. We included all retrospective series and case reports. A single author identified the studies, and all authors reviewed the selection until there was a consensus on which studies to include.

Key content and findings: The literature consisted of relatively small series, mixed between adult and pediatric patients, and the consensus remains that all symptomatic lesions should be excised via minimally invasive approach where feasible.

Conclusions: Surgical excision of symptomatic bronchogenic cysts remains the gold standard, with endoscopic drainage being reserved for diagnosis or as a temporizing measure in clinically unstable patients.

Central airway obstruction is a serious complication of various diseases, most often malignancy. Malignant etiologies include primary lung cancer as most common though metastases from various other cancers can obstruct the airways as well. Benign etiologies include inflammatory or fibrotic changes due to prior airway interventions (e.g., endotracheal intubation or tracheostomy) or specific autoimmune conditions. Different interventional modalities exist including various electrosurgical or mechanical debulking tools, though these are sometimes insufficient or contraindicated for the purpose of restoration of airway patency. The placement of stents is thus needed in certain particularly complex or refractory cases. Airway stenting requires careful patient selection and stent selection along with a thorough knowledge of relevant anatomy and procedural technique. Indeed, certain clinical presentations are better suited for stent placement and more likely to achieve a symptomatic benefit. Moreover, a variety of stents exist with each having different attributes that may better fit specific conditions. Complications must be managed properly as well. These include stent migration, granulation tissue formation, and stent-related infection which can have clinically significant consequences. In this review, we will discuss airway stenting for central airway obstruction with regard to these various subject areas as well as conclude with discussion of future research directions.

Spindle cell thymomas are the most common spindle cell neoplasms of the anterior mediastinum. These tumors belong to the group of thymic epithelial neoplasms and are known for their wide histomorphologic spectrum. This histological heterogeneity is the reason why unequivocal diagnosis can be challenging, especially when dealing with small biopsy material. Conversely, less conventional patterns of the tumor may also pose significant diagnostic problems in resected material and the differential diagnosis often includes other spindle cell neoplasms that are known to arise in the mediastinal cavity. These can be of variable origin and may share overlapping pathological features with spindle cell thymoma. Since spindle cell thymomas are tumors that primarily affect the adult population and predominantly arise from the thymic gland in the anterior mediastinum, this review will focus on the differential diagnosis with other spindle cell neoplasms that share similar demographic characteristics and, for the most part, originate from the anterior mediastinal compartment. These include other epithelial spindle cell tumors of thymic origin (sarcomatoid thymic carcinoma and spindle cell carcinoid tumor), mesenchymal neoplasms [solitary fibrous tumor (SFT), synovial sarcoma, and dedifferentiated liposarcoma] and various other tumors with spindle cell morphology, that may occasionally involve the anterior mediastinum. The clinical, pathological, immunohistochemical and molecular hallmarks of these lesions will be discussed and useful tips for the differential diagnosis with spindle cell thymoma will be provided.

Background: Mediastinal haemangioma is a rare type of tumour and accounts for ≤0.5% of all mediastinal tumours. Mediastinal haemangioma is often nonspecific upon examination by imaging. Mediastinal haemangioma diagnosis is difficult to confirm before surgery because the characteristic features of diagnostic imaging are poor, and these lesions are extremely rarely encountered in clinical practice.

Case description: We herein report a case of thoracoscopic resection of a cavernous haemangioma in the anterior mediastinum. A 40-year-old man was referred to our hospital for a health examination. A chest computed tomography scan showed a mass with irregular contrast enhancement and a smooth surface. Using video-assisted thoracoscopic surgery, the tumour was completely extirpated and confirmed histologically to be a cavernous haemangioma. The patient recovered well, was discharged, he has since had no recurrences, and continues to be closely monitored as an outpatient.

Conclusions: Mediastinal haemangiomas, a rare type of mediastinal tumour, are typically benign and located in the anterior mediastinum, and lack specific symptoms and relevant imaging features. We found that minimally invasive thoracoscopic resection provided a satisfactory view and facilitated correct handling of a mediastinal cavernous haemangioma. Although such tumours are mostly benign and the prognosis is good, we recommend aggressive surgical management to avoid missing malignant lesions.