Spontaneous pneumomediastinum and subcutaneous emphysema in avian influenza A (H5N6) human pneumonia

Spontaneous pneumomediastinum: A comprehensive review of diagnosis and management

Pneumomediastinum is a rare condition defined by the presence of air in the mediastinum. In the absence of traumatic injury, iatrogenic injury, or clear etiology, it is called spontaneous pneumomediastinum (SPM). Spontaneous pneumomediastinum most commonly occurs in younger individuals and has a self-limiting course with a good outcome. The purpose of the present manuscript is to systematically review the existing literature on SPM evaluation and management for updated clinical understanding of this condition. A literature search was conducted of publications about SPM on MEDLINE/PubMed and Google Scholar by identifying all the articles with key search terms "pneumomediastinum" and "spontaneous pneumomediastinum". Inclusion criteria were case series published in English between 1980 and 2023. In total, 24 case series were selected and reviewed to determine presenting symptoms, clinical signs and predisposing factors associated with spontaneous pneumomediastinum. Most patients were male; the average age at diagnosis was 26.3 years. The most common presenting symptoms were chest pain and dyspnea. The most common exam finding was subcutaneous emphysema, in 35.4% of patients. Only 5.9% had the classic Hamman's sign. Risk factors include history of asthma, history of smoking, and recent physical activity. This manuscript presents an extensive review of relevant literature highlighting the diagnosis and essential management of spontaneous pneumomediastinum.

A case report of pneumomediastinum in a COVID-19 patient treated with high-flow nasal cannula and review of the literature: Is this a "spontaneous" complication?

Oxygen support with high-flow nasal cannula (HFNC) is gentler than mechanical ventilation and may provide significant benefits, but more studies are needed to investigate the efficacy and safety of different respiratory supports in patients with COVID-19 pneumonia.

Spontaneous Subcutaneous Emphysema and Pneumomediastinum Associated With Influenza B Virus in a Young Male Adult: A Case Report

In this report, we present a case of influenza B-associated spontaneous pneumomediastinum (SPM) and subcutaneous emphysema (SE) in a young male patient. Although there are several causes responsible for this condition, it is considered extremely rare to occur spontaneously with no prior trauma or predisposing factors, especially in older age groups. Rare cases of SPM and SE, as described in several case reports worldwide, have been reported to have a benign course for the most part. Nevertheless, implementing unified management guidelines with clear protocols is highly recommended to prevent the potential unfavorable complications associated with these conditions.

Pulmonary Barotrauma Resulting from Mechanical Ventilation in 2 Patients with a Diagnosis of COVID-19 Pneumonia

BACKGROUND Invasive mechanical ventilation can cause pulmonary barotrauma due to elevated transpulmonary pressure and alveolar rupture. A significant proportion of COVID-19 patients with acute respiratory distress syndrome (ARDS) will require mechanical ventilation. We present 2 interesting cases that demonstrate the possibility of COVID-19-associated ARDS manifesting with pulmonary barotrauma at acceptable ventilatory pressures. CASE REPORT The first patient was a 71-year-old man who was intubated and placed on mechanical ventilation due to hypoxemic respiratory failure from SARS-CoV-2 infection. His partial pressure of O2 to fraction of inspired oxygen ratio (PaO2/FiO2) was 156. He developed subcutaneous emphysema (SE) and pneumomediastinum on day 5 of mechanical ventilation at ventilatory settings of positive end-expiratory pressure (PEEP) ≤15 cmH₂O, plateau pressure (Pplat) ≤25 cmH₂O and pulmonary inspiratory pressure (PIP) ≤30 cmH₂O. He was managed with 'blow-hole' incisions, with subsequent clinical resolution of subcutaneous emphysema. The second patient was a 58-year-old woman who was also mechanically ventilated due to hypoxemic respiratory failure from COVID-19, with PaO2/FiO2 of 81. She developed extensive SE with pneumomediastinum and pneumothorax while on mechanical ventilation settings PEEP 13 cmH₂O and PIP 28 cmH₂O, Pplat 18 cmH₂O, and FiO2 90%. SE was managed with blow-hole incisions and pneumothorax with chest tube. CONCLUSIONS Clinicians should be aware of pulmonary barotrauma as a possible complication of COVID-19 pulmonary disease, even at low ventilatory pressures.