The HEV Ventilator: at the interface between particle physics and biomedical engineering.

A high-quality, low-cost ventilator, dubbed HEV, has been developed by the particle physics community working together with biomedical engineers and physicians around the world. The HEV design is suitable for use both in and out of hospital intensive care units, provides a variety of modes and is capable of supporting spontaneous breathing and supplying oxygen-enriched air. An external air supply can be combined with the unit for use in situations where compressed air is not readily available. HEV supports remote training and post market surveillance via a Web interface and data logging to complement standard touch screen operation, making it suitable for a wide range of geographical deployment. The HEV design places emphasis on the ventilation performance, especially the quality and accuracy of the pressure curves, reactivity of the trigger, measurement of delivered volume and control of oxygen mixing, delivering a global performance which will be applicable to ventilator needs beyond the COVID-19 pandemic. This article describes the conceptual design and presents the prototype units together with a performance evaluation.

Pierre-Marie-Bamberger syndrome and solitary fibrous tumor: a rare association.

A solitary fibrous tumor originates in the pleura with variable degrees of invasion. Hypertrophic osteoarthropathy, known as Pierre-Marie-Bamberger syndrome, is characterized by clubbing of the fingers due to bone surface and soft tissue calcification, historically known as a bronchogenic carcinoma paraneoplastic syndrome; however, a few cases have been associated with solitary fibrous tumors. We describe the case of a 38-year-old woman who presented with clubbing of the fingers. Studies revealed an intrathoracic fibrous tumor that was successfully treated with improvement in symptoms.

Ascending necrotizing mediastinitis secondary to emphysematous pyelonephritis.

Mediastinal infections usually originate from postoperative complications or in a descending manner from a cervical infectious process; few reports have emerged describing an ascending trajectory. A 56-year-old woman with a Huang class 1 left emphysematous pyelonephritis was referred due to a progression of an ascending necrotizing mediastinitis. A left posterolateral thoracotomy was performed, drainage and thorough lavage were carried out with a successful outcome. We believe this is the first reported case of ascending necrotizing mediastinitis secondary to an emphysematous renal infection.

Systematic review of spontaneous pneumomediastinum: a survey of 22 years' data.

OBJECTIVE: To describe and clarify management protocols in relation to spontaneous pneumomediastinum, and try to integrate criteria on this subject. BACKGROUND: Thoracic physicians are faced with patients who present with gas in the mediastinum, frequently without an obvious etiologic factor. Published material contains heterogeneous information from which different conclusions can be drawn. METHODS: In a Medline search from 1990 to 2012, we collected data on mortality, morbidity, signs, symptoms, etiologic factors, and diagnostic methods. Standardized mean differences were calculated. RESULTS: We identified 600 patients in 27 papers with series of >5 patients without precipitating or etiologic factors previous to the clinical presentation, but athletic activity, drug abuse, and history of asthma played an apparent role in the disease process. Most patients complained of thoracic pain and dyspnea, with subcutaneous emphysema and Hamman's sign. The most common complication was tension pneumothorax. Morbidity was seen in 2.8%; no mortality has been reported so far. CONCLUSION: Spontaneous pneumomediastinum is a rare disease with a benign course, which should be treated conservatively unless a complication mandates an invasive procedure. An algorithm for diagnosis and treatment is offered, based on the available evidence.

Descending necrotizing mediastinitis below the tracheal carina.

BACKGROUND: Descending necrotizing mediastinitis is a dreadful disease with a high mortality rate, particularly when below the tracheal carina. This study describes the epidemiologic, clinical, and paraclinical features of patients treated for this condition. METHODS: We performed a single-center retrospective descriptive review of 60 patients with descending necrotizing mediastinitis below the tracheal carina, who were treated during a 7-year period, the largest study in the last 50 years. Demographic, clinical, paraclinical, and therapeutic variables were analyzed. RESULTS: 43 (71.7%) patients were male. The mean age was 41.2 ± 14.7 years. Mean hospital length of stay was 25.0 ± 19.8 days. Comorbidities were present in 46.7% of patients, diabetes mellitus being the most common. Odontogenic infections (45%) were the most frequent source of descending necrotizing mediastinitis. Cultures showed Gram-negative bacilli in 68.3%, Gram-positive cocci in 38.3%, and fungi in 6.7%. Mortality was 35% (21 patients); risk factors for mortality were age (>35 years), diabetes mellitus among other comorbidities, and associated complications. CONCLUSIONS: In this low socioeconomic status patient population, descending necrotizing mediastinitis below the carina causes high morbidity and mortality, the latter particularly associated with age, complications, diabetes mellitus and other comorbidities.

Giant lipoma of the breast.

Lipomas are benign mesenchymal tumors that develop in areas of abundant adipose tissue. Due to the fatty composition of the breast, difficulties in diagnosis, treatment, and reconstruction are often encountered. We report a case of a 55-year-old female with a giant tumor of the right breast that comprised most of its mass, causing breast asymmetry. A thorough preoperative evaluation, followed by an uneventful difficult surgical resection and reconstruction, resulted in diagnosis of a benign lipoma. The case prompted this report because of its challenging size, location, diagnosis, and reconstructive solution.

Descending necrotizing mediastinitis associated with spinal cord abscess.

A 58-year-old man with a history of Ludwig's angina was admitted with a spinal cord abscess at the level of C2-T1 and associated osteomyelitic destruction of vertebral bodies, spinal cord compression, and secondary quadriparesis, followed by descending mediastinitis. A right posterolateral thoracotomy and a cervicotomy drained purulent exudates. A tracheostomy was performed, and the patient was discharged after 84 days.

Mediastinal drainage in descending necrotizing mediastinitis.

Descending necrotizing mediastinitis has been thoroughly described in the past, but we could not find a detailed description of the technique to perform adequate drainage and lavage of all the mediastinal and thoracic spaces. We describe the procedure as we perform it, emphasizing the sites for incision and proper drainage of all the mediastinal compartments and the contralateral thoracic cavity.

Descending necrotizing mediastinitis and sternoclavicular joint osteomyelitis.

Descending necrotizing mediastinitis is usually associated with cervical or odontogenic infections. We describe a patient with blunt trauma to the chest 2 years earlier, and a slowly developing chest wall hematoma 18 months prior to admission, complicated by chronic sternoclavicular joint osteomyelitis, eventually leading to descending mediastinitis. Thoracotomy with drainage of the mediastinal spaces and multiple procedures for the sternoclavicular joint infection were successful. The rarity of this association and undefined optimal management prompted this report.

Descending necrotizing mediastinitis and thoracic cellulitis due to varicella.

A 22-year-old man with varicella had associated cervical enlargement, right upper thoracic anterior and suprascapular cellulitis, and mediastinitis. A tracheostomy, right posterolateral thoracotomy, cervicotomy, and upper thoracic fasciotomy were performed 14 h after admission, draining purulent exudates from all sites. The patient was discharged on postoperative day 22.

Thoracic necrotizing fasciitis due to snake ointment that progressed to a mediastinitis.

We report the case of a 42-year old diabetic male presenting with erythema of the neck and anterior right thoracic region secondary to the application of an ointment derived from rattlesnakes, progressing to a full-blown necrotizing fasciitis in a short period of time, with associated mediastinitis, thrombocytopaenia and sepsis. The patient died despite aggressive multidisciplinary medical and surgical treatment. We present this case due to the unusual aetiology and fulminating course.