From the Guidelines
Screening for mediastinitis should involve a combination of clinical assessment, laboratory tests, and imaging studies, with CT scanning with contrast being the imaging modality of choice, as it can detect fluid collections, gas bubbles, and soft tissue inflammation with high sensitivity, as supported by the most recent evidence 1. When evaluating patients for mediastinitis, it is essential to consider the clinical presentation, including symptoms such as fever, chest pain, sternal instability, purulent drainage from the sternum, and leukocytosis. Laboratory tests, including complete blood count with white cell differential, C-reactive protein, and erythrocyte sedimentation rate, should be performed to support the diagnosis. Blood cultures should also be obtained to identify causative organisms. Imaging studies play a crucial role in the diagnosis of mediastinitis. Chest radiography may show widening of the mediastinum or pneumomediastinum, but CT scanning with contrast is the preferred imaging modality due to its high sensitivity in detecting fluid collections, gas bubbles, and soft tissue inflammation. MRI may be useful in cases where CT findings are equivocal, as it can provide further tissue characterization and detect invasion of the mass across tissue planes, including the chest wall and diaphragm, and involvement of neurovascular structures, as noted in the study by 1. In post-cardiac surgery patients, sternal wound assessment is crucial, looking for dehiscence, drainage, or crepitus. Early diagnosis is essential, as mediastinitis carries significant mortality, particularly when diagnosis is delayed. The condition requires prompt antibiotic therapy based on culture results and often surgical debridement. Risk factors to consider include diabetes, obesity, immunosuppression, prolonged surgery, and bilateral internal mammary artery harvesting in cardiac surgery patients. Some key points to consider when screening for mediastinitis include:
- Clinical assessment and laboratory tests to support the diagnosis
- Imaging studies, including CT scanning with contrast, to detect fluid collections, gas bubbles, and soft tissue inflammation
- MRI may be useful in cases where CT findings are equivocal
- Sternal wound assessment is crucial in post-cardiac surgery patients
- Early diagnosis and prompt treatment are essential to reduce mortality and improve outcomes, as emphasized by the study 1.
From the Research
Screening for Mediastinitis
To screen for mediastinitis, the following methods can be employed:
- Radiographic studies with or without contrast material as the initial radiological work-up 2
- Computed tomography (CT) of the neck and thorax as the method of choice for diagnostics and control of therapeutic success 3
- Cross-sectional imaging techniques, such as CT and magnetic resonance imaging, to diagnose and evaluate the site and extent of mediastinal involvement 2
- Conventional chest radiography, although it may be misleading in the diagnosis of mediastinitis 2
Imaging Techniques
The following imaging techniques can be used to screen for mediastinitis:
- CT scans to distinguish diffuse mediastinitis from a localized drainable abscess 4
- CT scans to identify associated empyemas and other secondary complications 4
- Magnetic resonance imaging to guide the choice of the optimal therapeutic approach 2
Clinical Presentation
The clinical presentation of mediastinitis can vary widely depending on the cause of infection, and lack of knowledge or awareness of the illness and mostly unspecific clinical symptoms often delay diagnosis and thereby the start of adequate therapy 3
Diagnostic Challenges
The diagnosis of mediastinitis can be challenging, and CT findings may not always be reliable in distinguishing mediastinitis from benign postoperative changes in the absence of mediastinal gas 4