Prevention of COVID-19 in Thoracic Surgery Patients: Lessons Learned during the First Pandemic Wave.

BACKGROUND: The aim of this retrospective study was to investigate the implementation of measures to prevent perioperative COVID-19 in thoracic surgery during the first wave of the COVID-19 pandemic 2020 allowing a continued surgical treatment of patients. METHODS: The implemented preventive measures in patient management of the thoracic surgery department of the Asklepios Lung Clinic Munich-Gauting, Germany were retrospectively analyzed. Postoperative COVID-19 incidence before and after implementation of preventive measures was investigated. Patients admitted for thoracic surgical procedures between March and May 2020 were included in the study. Patient characteristics were analyzed. For the early detection of putative postoperative COVID-19 symptoms, typical post-discharge symptomatology of thoracic surgery patients was compared to non-surgical patients hospitalized for COVID-19. RESULTS: Thirty-five surgical procedures and fifty-seven surgical procedures were performed before and after implementation of the preventive measures, respectively. Three patients undergoing thoracic surgery before implementation of preventive measures developed a COVID-19 pneumonia post-discharge. After implementation of preventive measures, no postoperative COVID-19 cases were identified. Fever, dyspnea, dry cough and diarrhea were significantly more prevalent in COVID-19 patients compared to normally recovering thoracic surgery patients, while anosmia, phlegm, low energy levels, body ache and nausea were similarly frequent in both groups. CONCLUSIONS: Based on the lessons learned during the first pandemic wave, we here provide a blueprint for successful easily implementable preventive measures minimizing SARS-CoV-2 transmission to thoracic surgery patients perioperatively. While symptoms of COVID-19 and the normal postoperative course of thoracic surgery patients substantially overlap, we found dyspnea, fever, cough, and diarrhea significantly more prevalent in COVID-19 patients than in normally recovering thoracic surgery patients. These symptoms should trigger further diagnostic testing for postoperative COVID-19 in thoracic surgery patients.

Predicting the effectiveness of high-flow oxygen therapy in COVID-19 patients: a single-centre observational study.

BACKGROUND: High-flow nasal cannula (HFNC) therapy is a helpful tool in the treatment of hypoxaemic respiratory failure. However, the clinical parameters predicting the effectiveness of HFNC in coronavirus-19 disease (COVID-19) patients remain unclear. METHODS: Sixteen COVID-19 patients undergoing HFNC in the Asklepios Lung Clinic Munich-Gauting, Germany between 16 March and 3 June 2020 were retrospectively included into the study. Seven patients successfully recovered after HFNC (Group 1), while 9 patients required intubation upon HFNC failure (Group 2). Relevant predictors for an effective HFNC therapy were analysed on day 0 and 4 after HFNC initiation via receiver operating characteristics. RESULTS: The groups did not differ significantly in terms of age, sex, body mass index, and comorbidities. Five patients died in Group 2 upon disease progression and HFNC failure. Group 1 required a lower oxygen supplementation (FiO2 0.46 [0.31-0.54] vs. 0.72 [0.54-0.76], P = 0.022) and displayed a higher PaO2/FiO2 ratio (115 [111-201] vs. 93.3 [67.2-145], P = 0.042) on day 0. In Group 2, fever persisted on day 4 (38.5 [38.0-39.4]°C vs. 36.5 [31.1-37.1]°C, P = 0.010). Serum C-reactive protein (CRP) levels > 108 mg L-1 (day 0) and persistent oxygen saturation < 89% and PaO2/FiO2 ratio < 91 (day 4) were identified as significant predictors for HFNC failure (area under curve 0.929, 0.933, and 0.893). CONCLUSIONS: Elevated oxygen saturation, decreased FiO2 and reduced serum CRP on day 4 significantly predict HFNC effectiveness in COVID-19 patients. Based on these parameters, larger prospective studies are necessary to further investigate the effectiveness of HFNC in the treatment of COVID-19-associated hypoxaemic respiratory failure.

Automated quantitative thin slice volumetric low dose CT analysis predicts disease severity in COVID-19 patients.

PURPOSE: This study aimed to identify predictive (bio-)markers for COVID-19 severity derived from automated quantitative thin slice low dose volumetric CT analysis, clinical chemistry and lung function testing. METHODS: Seventy-four COVID-19 patients admitted between March 16th and June 3rd 2020 to the Asklepios Lung Clinic Munich-Gauting, Germany, were included in the study. Patients were categorized in a non-severe group including patients hospitalized on general wards only and in a severe group including patients requiring intensive care treatment. Fully automated quantification of CT scans was performed via IMBIO CT Lung Texture analysis™ software. Predictive biomarkers were assessed with receiver-operator-curve and likelihood analysis. RESULTS: Fifty-five patients (44% female) presented with non-severe COVID-19 and 19 patients (32% female) with severe disease. Five fatalities were reported in the severe group. Accurate automated CT analysis was possible with 61 CTs (82%). Disease severity was linked to lower residual normal lung (72.5% vs 87%, p = 0.003), increased ground glass opacities (GGO) (8% vs 5%, p = 0.031) and increased reticular pattern (8% vs 2%, p = 0.025). Disease severity was associated with advanced age (76 vs 59 years, p = 0.001) and elevated serum C-reactive protein (CRP, 92.2 vs 36.3 mg/L, p < 0.001), lactate dehydrogenase (LDH, 485 vs 268 IU/L, p < 0.001) and oxygen supplementation (p < 0.001) upon admission. Predictive risk factors for the development of severe COVID-19 were oxygen supplementation, LDH >313 IU/L, CRP >71 mg/L, <70% normal lung texture, >12.5% GGO and >4.5% reticular pattern. CONCLUSION: Automated low dose CT analysis upon admission might be a useful tool to predict COVID-19 severity in patients.

Clinical Course of Three Postoperative Symptomatic COVID-19 Cases in Patients After Lung Lobectomy.

The novel coronavirus disease 2019 is a highly contagious viral infection caused by the severe acute respiratory syndrome coronavirus 2 virus. Its rapid spread and severe clinical presentation influence patient management in all specialties including thoracic surgery. We report 3 cases of coronavirus disease 2019 occurring in patients shortly after thoracotomy and thoracoscopy procedures, illustrating the imminent threat of severe acute respiratory syndrome coronavirus 2 infection for thoracic surgery patients.

CD8 T-cell induction against vascular endothelial growth factor receptor 2 by Salmonella for vaccination purposes against a murine melanoma.

The Salmonella type III secretion system (T3SS) efficiently translocates heterologous proteins into the cytosol of eukaryotic cells. This leads to an antigen-specific CD8 T-cell induction in mice orally immunized with recombinant Salmonella. Recently, we have used Salmonella's T3SS as a prophylactic and therapeutic intervention against a murine fibrosarcoma. In this study, we constructed a recombinant Salmonella strain translocating the immunogenic H-2D(b)-specific CD8 T-cell epitope VILTNPISM (KDR2) from the murine vascular endothelial growth factor receptor 2 (VEGFR2). VEGFR2 is a member of the tyrosine protein kinase family and is upregulated on proliferating endothelial cells of the tumor vasculature. After single orogastric vaccination, we detected significant numbers of KDR2-tetramer-positive CD8 T cells in the spleens of immunized mice. The efficacy of these cytotoxic T cells was evaluated in a prophylactic setting to protect mice from challenges with B16F10 melanoma cells in a flank tumor model, and to reduce dissemination of spontaneous pulmonary melanoma metastases. Vaccinated mice revealed a reduction of angiogenesis by 62% in the solid tumor and consequently a significant decrease of tumor growth as compared to non-immunized mice. Moreover, in the lung metastasis model, immunization with recombinant Salmonella resulted in a reduction of the metastatic melanoma burden by approximately 60%.