Thomas Strecker

Background/Objectives: Early tracheostomy seems favorable in prolonged ventilated patients after surgery. Hence, predicting tracheostomy after cardiac surgery is essential. Recently proposed prediction models aim to support this decision-making process, but their diagnostic validity across other patient populations remains uncertain. Methods: A retrospective single-center study was performed at a university hospital. The patient sample included consecutive patients between 2010 and 2020 who underwent cardiac surgery. Patients who underwent tracheostomy after cardiac surgery were assigned to the intervention group. Control group patients, who had not undergone tracheostomy, were randomly assigned to the group. An existing model was evaluated by receiver operating characteristics curve analysis. Four sets of risk features were chosen depending on results from regression analysis, lasso regularization, random forest or clinical domain knowledge. Newly developed models were created using machine learning methods: random forest, naïve Bayes, nearest neighbor and deep learning. Multiple models were trained with either feature set and then assessed using confusion matrices on an independent test set. Results: A total of 4744 patients were included in this study. One-hundred and eighteen patients were included in the tracheostomy group. Diagnostic accuracy of the existing model showed insufficient discrimination (area under the curve (AUC) = 0.57). Likewise, newly developed models also showed overall poor diagnostic discrimination across all feature sets and algorithms. Conclusions: This study shows the diagnostic limitations of retrospective clinical data for the diagnostic prediction of tracheostomy, thereby informing the design of future prospective diagnostic studies. Training new models should not rely on retrospective data alone. Instead, prospective data collection and integration of physiological or imaging-based diagnostics could likely contribute to the development of a good classifier.

Patients with dilated cardiomyopathy or ischemic cardiomyopathy and severe ventricular dysfunction with acute-on chronic cardiogenic shock oftentimes requires a temporarily mechanical support as a bridge to heart transplantation or implantation of a permanent left ventricular assist device. Herein, we report a middle-age patient with refractory acute-on chronic cardiogenic shock supported by a low-invasive left ventricle assist device Impella 5.5 ^® for the longest known duration in the literature as a successful bridge to left ventricular assist device implantation. While Impella support, the patient remained extubated and conscious, received regular physical therapy and was mobile on the ward. He wanted to wait as long as possible for an heart transplantation. Since waiting for a suitable donor organ any longer was no realistic option, a permanent left ventricular assist device was implanted successfully with over 1 year follow-up.

Hyperglycemia and diabetic ketoacidosis are serious and life-threatening emergencies in diabetes patients. Early recognition of the symptoms of these disorders and their management are essential. Therapy is adequate rehydration, insulin treatment, electrolyte replacement, and handling of the underlying causative disease. Herein, we present an 83-year-old male with an extremely altered blood gas analysis after a surgical procedure of his left hand due to a phlegmon and describe the successful treatment through intensive care.

Streptococcal toxic shock syndrome is a severe, invasive and life-threatening infection associated with a high risk of rapid multiorgan failure. It is associated with high morbidity and mortality. Streptococcal toxic shock syndrome is very commonly caused by group A- Streptococcus pyogenes, ß-haemolytic streptococcus, a typical human-specific gram-positive bacterial pathogen. We present here the case report of a 54-year-old man with a rapidly progressive streptococcal toxic shock syndrome due to necrotising fasciitis of the left lower limb and describe the successful treatment through close interdisciplinary care.

Aortic dissection is a life-threatening cardiovascular disease. Hereditary disorders are responsible for a small percentage of cases. Nonetheless, it is important to identify genetic causes, as they are often autosomal dominantly inherited and are of life-saving importance if we can identify persons at risk. Mutations of the ACTA2 gene are the most common cause of non-syndromic familial aortic disease. Exploration of the genetic background in suspected familial cases and determination of the exact etiology are mandatory for management and establishing appropriate follow-up strategies due to the risk of fatal recurrences. Herein, we present a 21-year-old male with a familial acute aortic dissection associated with novel ACTA2 germline variant and discuss the management and surveillance considerations.

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT), is a rare SMARCA4-driven aggressive malignancy of young age characteristically associated with paraneoplastic hypercalcemia. Comparable neoplasms/presentations have not been reported in males. A 39-year-old male heart transplant recipient (HTX 40 months previously) presented with multiple liver nodules and hypercalcemic crisis. The serum parathyroid hormone-related protein (PTHrp) was significantly elevated (241 pg/ml; reference value < 57). Liver biopsy showed poorly differentiated partially rhabdoid neoplasm expressing pancytokeratin, CK20, and focally GATA3, SATB2, p63, and SALL4. The tumor cells showed dual loss of SMARCA4 and SMARCA2. He died of irreversible multiorgan failure one week after admission. To our knowledge, this is the first report highlighting the rare occurrence of paraneoplastic hypercalcemia associated with SMARCA4-deficient malignancies in males. Although the immunophenotype suggests urothelial or upper gastrointestinal tract origin, the exact primary tumor site could not be ascertained due to rapid death of the patient. SMARCA4 immunohistochemistry should be included in the workup of neoplasms associated with hypercalcemia irrespective of gender and site.