Changes in utilization and outcomes of mechanical ventilation of COVID-19 during the course of the pandemic in Germany in 2020: an observational study of 7,490 patients

RationaleThe role of non-invasive ventilation (NIV) in severe COVID-19 remains a matter of debate. ObjectivesTo determine the utilization and outcome of NIV in COVID-19 in an unbiased cohort. MethodsObservational study of confirmed COVID-19 cases of claims data of the Local Health Care Funds comparing patients with non-invasive and invasive mechanical ventilation (IMV) between spring versus autumn period 2020. Measurements and Main ResultsNationwide cohort of 7490 cases (median/IQR age 70/60-79 years, 66% male) 3851 (51%) patients primarily received IMV without NIV, 1614 (22%) patients received NIV without subsequent intubation, and 1247 (17%) patients had NIV failure (NIV-F), defined by subsequent endotracheal intubation. The proportion of patients who received invasive MV decreased from 74% to 39% during the second period. Accordingly, the proportion of patients with NIV exclusively increased from 10% to 28%, and those failing NIV increased from 9% to 21%. Median length of hospital stay decreased from 26 to 22 days, and duration of MV decreased from 11.6 to 7.6 days. The NIV failure rate decreased from 49% to 42%. Overall mortality remained unchanged (51% versus 53%). Mortality was 39% with NIV-only, 52% with IMV and 66% with NIV-F with mortality rates steadily increasing from 58% in early NIV-F (day 1) to 75% in late NIV-F (>4 days). ConclusionUtilization of NIV rapidly increased during the autumn period, which was associated with a reduced duration of MV, but not with overall mortality. High NIV-F rates are associated with increased mortality, particularly in late NIV-F. FundingInstitutional support and physical resources were provided by the University Witten/Herdecke and Kliniken der Stadt Koln and the Federal Association of the Local Health Care Funds. At a Glance CommentaryO_ST_ABSScientific Knowledge on the SubjectC_ST_ABSCurrent management of ventilatory support in COVID-19 patients with respiratory failure is heterogeneous. Despite increasing use of non-invasive ventilation (NIV), defining intubation criteria still remains a matter of uncertainty and discussion, especially with regard to the balance between the NIV benefits and the risk of NIV failure. In addition, robust data concerning the influence of the duration and failure of NIV on intubation and mortality rates are still missing, although the time span between initiation of NIV and subsequent intubation in case of respiratory failure progression is suggested to influence patient outcome. What This Study Adds to the FieldThis is the first large observational study describing differences of ventilatory strategies between the spring and autumn period of the SARS-CoV-2 pandemic in Germany and provides the in-hospital mortality rate of 7,490 patients who received mechanical ventilation. The increased utilization of NIV from 10% (first period) to 29% (second period) was associated with overall reduced durations of mechanical ventilation and length of hospital stay, but overall mortality remained comparably high and reached 51%, 53% respectively. Patients succeeding with NIV had lower mortality rates than those getting intubated without preceding NIV attempts, but those failing NIV had higher mortality rates, respectively, and this became even more predominant in late NIV failure. The present observational study shows the increasing role of NIV in the concert of ICU medicine related to COVID-19, but also clearly addresses its risks in addition to its benefits, both impacting on mortality.

Defective NETs Clearance contributes to sustained FXII Activation in COVID-19-associated Pulmonary Thrombo-Inflammation

BackgroundCoagulopathy and inflammation are hallmarks of Coronavirus disease 2019 (COVID-19) and are associated with increased mortality. Clinical and experimental data have revealed a role for neutrophil extracellular traps (NETs) in COVID-19 disease. The mechanisms that drive thrombo-inflammation in COVID-19 are poorly understood. MethodsWe performed proteomic analysis and immunostaining of postmortem lung tissues from COVID-19 patients and patients with other lung pathologies. We further compared coagulation factor XII (FXII) and DNase activities in plasma samples from COVID-19 patients and healthy control donors and determined NET-induced Factor XIII (FXII) activation using a chromogenic substrate assay. FindingsFXII expression and activity were increased in the lung parenchyma, within the pulmonary vasculature and in fibrin-rich alveolar spaces of postmortem lung tissues from COVID-19 patients. In agreement with this, plasma FXII activation (FXIIa) was increased in samples from COVID-19 patients. Furthermore, FXIIa colocalized with NETs in COVID-19 lung tissue indicating that NETs accumulation leads to FXII contact activation in COVID-19. We further showed that an accumulation of NETs is partially due to impaired NET clearance by extracellular DNases as DNase substitution improved NET dissolution and reduced FXII activation in vitro. InterpretationCollectively, our study supports that the NETs/FXII axis contributes to the pathogenic chain of procoagulant and proinflammatory responses in COVID-19. Targeting both, NETs and FXIIa, could provide a strategy to mitigate COVID-19-induced thrombo-inflammation. FundingThis study was supported by the European Union (840189), the Werner Otto Medical Foundation Hamburg (8/95) and the German Research Foundation (FR4239/1-1, A11/SFB877, B08/SFB841 and P06/KFO306).

Cardiac SARS-CoV-2 infection is associated with distinct transcriptomic changes within the heart

1BackgroundAnalyses in hospitalized patients and small autopsy series suggest that severe SARS-CoV-2 infection may affect the heart. We investigated heart tissue by in situ hybridization, immunohistochemistry and RNA sequencing in consecutive autopsy cases to quantify virus load and characterize cardiac involvement in COVID-19. MethodsLeft ventricular tissue from 95 deceased with diagnosed SARS-CoV-2 infection undergoing autopsy was analyzed and clinical data were collected. RNA was isolated to examine virus load of SARS- CoV-2 and its replication in the heart. A virus load >1000 copies per {micro}g RNA was defined as relevant. Viral RNA and inflammatory cells were assessed using histology. RNA sequencing and gene ontology (GO) enrichment were performed in 10 cases with high cardiac virus load and 10 age-matched cases without cardiac infection. ResultsA relevant SARS-CoV-2 virus load was detected in 41 out of 95 deceased (43%). The median cardiac virus load was 7952 copies per {micro}g RNA (IQR 2507, 32 005). In situ hybridization revealed SARS- CoV-2 RNA primarily in the interstitium or interstitial cells. Virus detection was not associated with increased inflammatory cells. Relevant cardiac infection was associated with increased expression of the entry factor TMPRSS2. Cardiac virus replication was found in 14/95 hearts (15%). Remarkably, cardiac virus replication was associated with shorter time between diagnosis and death. RNA sequencing revealed clear activation of immune response pathways to virus infection and destruction of cardiomyocytes. Hearts with high virus load showed activation of the GO term "extracellular exosomes". ConclusionSARS-CoV-2 infection including virus replication and distinct transcriptomic alterations without signs of myocarditis demonstrate a cardiac involvement. In this autopsy series, cardiac replication of SARS-CoV-2 was associated with early death.

Low and high infection dose transmission of SARS-CoV-2 in the first COVID-19 clusters in Northern Germany

ObjectivesWe used viral genomics to deeply analyze the first SARS-CoV-2 infection clusters in the metropolitan region of Hamburg, Germany. Epidemiological analysis and contact tracing together with a thorough investigation of virus variant patterns revealed low and high infection dose transmissions to be involved in transmission events. MethodsInfection control measures were applied to follow up contract tracing. Metagenomic RNA- and SARS-CoV-2 amplicon sequencing was performed from 25 clinical samples for sequence analysis and variant calling. ResultsThe index patient acquired SARS-CoV-2 in Italy and after his return to Hamburg transmitted it to 2 out of 132 contacts. Virus genomics and variant pattern clearly confirms the initial local cluster. We identify frequent single nucleotide polymorphisms at positions 241, 3037, 14408, 23403 and 28881 previously described in Italian sequences and now considered as one major genotype in Europe. While the index patient showed a single nucleotide polymorphism only one variant was transmitted to the recipients. Different to the initial cluster, we observed in household clusters occurring at the time in Hamburg also intra-host viral species transmission events. ConclusionsSARS-CoV-2 variant tracing highlights both, low infection dose transmissions suggestive of fomites as route of infection in the initial cluster and high and low infection dose transmissions in family clusters indicative of fomites and droplets as infection routes. This suggests (1) single viral particle infection can be sufficient to initiate SARS-CoV-2 infection and (2) household/family members are exposed to high virus loads and therefore have a high risk to acquire SARS-CoV-2.

The majority of male patients with COVID-19 present low testosterone levels on admission to Intensive Care in Hamburg, Germany: a retrospective cohort study.

Males develop more severe SARS-CoV-2 infection related disease outcome than females. Herein, sex hormones were repeatedly proposed to play an important role in Covid-19 pathophysiology and immunity. However, it is yet unclear whether sex hormones are associated with Covid-19 outcome in males and females. In this study, we analyzed sex hormones, cytokine and chemokine responses as well as performed a large profile analysis of 600 metabolites in critically-ill male and female Covid-19 patients in comparison to healthy controls and patients with coronary heart diseases as a prime Covid-19 comorbidity. We here show that dysregulated sex hormones, IFN-{gamma} levels and unique metabolic signatures are associated with critical illness in Covid-19 patients. Both, male and female Covid-19 patients, present elevated estradiol levels which positively correlates with IFN-{gamma} levels. Male Covid-19 patients additionally display severe testosterone and triglyceride deficiencies as compared to female patients and healthy controls. Our results suggest that male Covid-19 patients suffer from multiple metabolic disorders, which may lead to higher risk for fatal outcome. These findings will help to understand molecular pathways involved in Covid-19 pathophysiology.

Clinical evaluation of a SARS-CoV-2 RT-PCR assay on a fully automated system for rapid on-demand testing in the hospital setting

1BackgroundThe ongoing SARS-CoV-2 pandemic presents a unique challenge for diagnostic laboratories around the world. Automation of workflows in molecular diagnostics are instrumental for coping with the large number of tests ordered by clinicians, as well as providing fast-tracked rapid testing for highly urgent cases. In this study we evaluated a SARS-CoV-2 LDT for the NeuMoDx 96 system, a fully automated device performing extraction and real-time PCR. MethodsA publicly available SARS-CoV-2 RT-PCR assay was adapted for the automated system. Analytical performance was evaluated using in-vitro transcribed RNA and clinical performance was compared to the cobas 6800-based reference assay within the lab. ResultsThe NeuMoDx-sarbeco-LDT displayed good analytical performance with an LoD of 95.55 cp/ml and no false positives during evaluation of cross-reactivity. A total of 176 patient samples were tested with both the Sarbeco-LDT and the reference assay. Positive and negative agreement were 100% and 99.2% respectively. Invalid-rate was 6.3%. ConclusionThe NeuMoDx-sarbeco-LDT showed analytical and clinical performance comparable to the cobas6800-based reference assay. Due to its random-access workflow concept and rapid time-to-result of about 80 minutes, the device is very well suited for providing fast-tracked SARS-CoV-2 diagnostics for urgent clinical samples in the hospital setting. HighlightsO_LIA publicly available SARS-CoV-2 RT-PCR assay was adapted and evaluated on the open mode of the NeuMoDx 96 system (Qiagen) C_LIO_LIThe assay showed comparable analytical and clinical performance to the reference assay C_LIO_LIFast turn-around times (80 minutes) and random-access workflow of the system makes the assay well suited for urgent clinical samples. C_LI