Untuned antiviral immunity in COVID-19 revealed by temporal type I/III interferon patterns and flu comparison.

A central paradigm of immunity is that interferon (IFN)-mediated antiviral responses precede pro-inflammatory ones, optimizing host protection and minimizing collateral damage1,2. Here, we report that for coronavirus disease 2019 (COVID-19) this paradigm does not apply. By investigating temporal IFN and inflammatory cytokine patterns in 32 moderate-to-severe patients with COVID-19 hospitalized for pneumonia and longitudinally followed for the development of respiratory failure and death, we reveal that IFN-λ and type I IFN production were both diminished and delayed, induced only in a fraction of patients as they became critically ill. On the contrary, pro-inflammatory cytokines such as tumor necrosis factor (TNF), interleukin (IL)-6 and IL-8 were produced before IFNs in all patients and persisted for a prolonged time. This condition was reflected in blood transcriptomes wherein prominent IFN signatures were only seen in critically ill patients who also exhibited augmented inflammation. By comparison, in 16 patients with influenza (flu) hospitalized for pneumonia with similar clinicopathological characteristics to those of COVID-19 and 24 nonhospitalized patients with flu with milder symptoms, IFN-λ and type I IFN were robustly induced earlier, at higher levels and independently of disease severity, whereas pro-inflammatory cytokines were only acutely produced. Notably, higher IFN-λ concentrations in patients with COVID-19 correlated with lower viral load in bronchial aspirates and faster viral clearance and a higher IFN-λ to type I IFN ratio correlated with improved outcome for critically ill patients. Moreover, altered cytokine patterns in patients with COVID-19 correlated with longer hospitalization and higher incidence of critical disease and mortality compared to flu. These data point to an untuned antiviral response in COVID-19, contributing to persistent viral presence, hyperinflammation and respiratory failure.

Association Between Baseline Driving Pressure and Mortality in Very Old Patients with ARDS.

RATIONALE: Due to effects of aging on the respiratory system, it is conceivable that the association between driving pressure and mortality depends on age. OBJECTIVE: We endeavored to evaluate whether the association between driving pressure and mortality of patients with acute respiratory distress syndrome (ARDS) varies across the adult lifespan, hypothesizing that it is stronger in older, including very old (≥80 years), patients. METHODS: We performed a secondary analysis of individual patient-level data from seven ARDS Network and PETAL Network randomized controlled trials ("ARDSNet cohort"). We tested our hypothesis in a second, independent, national cohort ("Hellenic cohort"). We performed both binary logistic and Cox regression analyses including the interaction term between age (as a continuous variable) and driving pressure at baseline (i.e., the day of trial enrollment) as the predictor, and 90-day mortality as the dependent variable. FINDINGS: Based on data from 4567 patients with ARDS included in the ARDSNet cohort, we found that the effect of driving pressure on mortality depended on age (p=0.01 for the interaction between age as a continuous variable and driving pressure). The difference in driving pressure between survivors and non-survivors significantly changed across the adult lifespan (p<0.01). In both cohorts, a driving pressure threshold of 11 cmH2O was associated with mortality in very old patients. INTERPRETATION: Data from randomized controlled trials with strict inclusion criteria suggest that the effect of driving pressure on mortality of patients with ARDS may depend on age. These results may advocate for a personalized age-dependent mechanical ventilation approach.

Unfractionated heparin reduces hepcidin levels in critically ill patients.

A strong anti-hepcidin activity has been observed in heparins. Mean hepcidin levels were significantly reduced compared to baseline, following the first day of unfractionated heparin administration in critically patients. Heparin displayed a strong independent negative association with hepcidin. These results may lead to future treatment methods of forms of anaemia characterised by hepcidin excess, common among the critically ill.

Variation of endothelium-related hemostatic factors during sepsis.

OBJECTIVE: The thrombomodulin/protein C and VWF/ADAMTS-13 pathways are disturbed in sepsis and have been implicated in the coagulation disorders that characterize the septic syndrome. We aimed to assess the variation of these endothelial parameters during sepsis and their putative association with outcome, in critically ill, septic patients. METHODS: We monitored 34 septic patients, 23 of whom improved (group A) while 11 deteriorated (group B). We assessed ADAMTS-13 levels, VWF activity, soluble thrombomodulin, and protein C activity upon admission to the ICU (time point 0) and at the time of a change in the clinical condition (remission or deterioration, time point 1). RESULTS: In group A, thrombomodulin and VWF increased at time point 1 compared to time point 0 (P = 0.011, P = 0.028, respectively). In group B, protein C and ADAMTS-13 significantly decreased (P = 0.023, P = 0.026, respectively), while VWF, VWF/ADAMTS-13 ratio, and the thrombomodulin/protein C ratio increased (P = 0.02, P = 0.002, P = 0.01, respectively). Protein C (> or ≤17%) and ADAMTS-13 percentage difference (> or ≤22%) were independently associated with sepsis outcome among the endothelial variables tested. CONCLUSIONS: An ongoing endothelial/hemostatic disorder was established during sepsis, observed even at clinical improvement. Among the variables tested, protein C and ADAMTS-13 change were associated with outcome.

Colistin Population Pharmacokinetics after Application of a Loading Dose of 9 MU Colistin Methanesulfonate in Critically Ill Patients.

Colistin has been revived, in the era of extensively drug-resistant (XDR) Gram-negative infections, as the last-resort treatment in critically ill patients. Recent studies focusing on the optimal dosing strategy of colistin have demonstrated the necessity of a loading dose at treatment initiation (D. Plachouras, M. Karvanen, L. E. Friberg, E. Papadomichelakis, A. Antoniadou, I. Tsangaris, I. Karaiskos, G. Poulakou, F. Kontopidou, A. Armaganidis, O. Cars, and H. Giamarellou, Antimicrob Agents Chemother 53:3430-3436, 2009, http://dx.doi.org/10.1128/AAC.01361-08; A. F. Mohamed, I. Karaiskos, D. Plachouras, M. Karvanen, K. Pontikis, B. Jansson, E. Papadomichelakis, A. Antoniadou, H. Giamarellou, A. Armaganidis, O. Cars, and L. E. Friberg, Antimicrob Agents Chemother 56:4241- 4249, 2012, http://dx.doi.org/10.1128/AAC.06426-11; S. M. Garonzik, J. Li, V. Thamlikitkul, D. L. Paterson, S. Shoham, J. Jacob, F. P. Silveira, A. Forrest, and R. L. Nation, Antimicrob Agents Chemother 55:3284-3294, 2011, http://dx.doi.org/10.1128/AAC.01733-10). In 19 critically ill patients with suspected or microbiologically documented infections caused by XDR Gram-negative strains, a loading dose of 9 MU colistin methanesulfonate (CMS) (∼ 270 mg colistin base activity) was administered with a maintenance dose of 4.5 MU every 12 h, commenced after 24 h. Patients on renal replacement were excluded. CMS infusion was given over 30 min or 1 h. Repeated blood sampling was performed after the loading dose and after the 5th or 6th dose. Colistin concentrations and measured CMS, determined after hydrolization to colistin and including the partially sulfomethylated derivatives, were determined with a liquid chromatography-tandem mass spectrometry assay. Population pharmacokinetic analysis was conducted in NONMEM with the new data combined with data from previous studies. Measured colistimethate concentrations were described by 4 compartments for distribution and removal of sulfomethyl groups, while colistin disposition followed a 1-compartment model. The average observed maximum colistin A plus B concentration was 2.65 mg/liter after the loading dose (maximum time was 8 h). A significantly higher availability of the measured A and B forms of colistimethate and colistin explained the higher-than-expected concentrations in the present study compared to those in previous studies. Creatinine clearance was a time-varying covariate of colistimethate clearance. The incidence of acute renal injury was 20%.

Implication of Interleukin (IL)-18 in the pathogenesis of chronic obstructive pulmonary disease (COPD).

Interleukin (IL)-18 is a pro-inflammatory cytokine that was firstly described as an interferon (IFN)-γ-inducing factor. Similar to IL-1ß, IL-18 is synthesized as an inactive precursor requiring processing by caspase-1 into an active cytokine. The platform for activating caspase-1 is known as the inflammasome, a multiple protein complex. Macrophages and dendritic cells are the primary sources for the release of active IL-18, whereas the inactive precursor remains in the intracellular compartment of mesenchymal cells. Finally, the IL-18 precursor is released from dying cells and processed extracellularly. IL-18 has crucial host defense and antitumor activities, and gene therapy to increase IL-18 levels in tissues protects experimental animals from infection and tumor growth and metastasis. Moreover, multiple studies in experimental animal models have shown that IL-18 over-expression results to emphysematous lesions in mice. The published data prompt to the hypothesis that IL-18 induces a broad spectrum of COPD-like inflammatory and remodeling responses in the murine lung and also induces a mixed type 1, type 2, and type 17 cytokine responses. The majority of studies identify IL-18 as a potential target for future COPD therapeutics to limit both the destructive and remodeling processes occurring in COPD lungs.

Elevated biomarkers of endothelial dysfunction/activation at ICU admission are associated with sepsis development.

Widespread endothelial activation and dysfunction often precede clinical sepsis. Several endothelium-related molecules have been investigated as potential biomarkers for early diagnosis and/or prognosis of sepsis, providing different results depending on study designs. Such factors include endothelial adhesion molecules like E- and P-selectin, and the intercellular adhesion molecule-1, vascular endothelial cadherin, growth factors such as Angiopoietin-1 and -2 and vascular endothelial growth factor, as well as von Willebrand factor antigen. We sought to investigate whether circulating biomarkers of endothelial activation/dysfunction measured at ICU admission are associated with subsequent sepsis development. Eighty-nine critically-ill patients admitted to a general ICU who met no sepsis criteria were studied. Plasma or serum levels of the above-mentioned endothelium-derived molecules were measured during the first 24h post ICU; acute physiology and chronic health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores, age, sex, diagnostic category, and circulating procalcitonin (PCT) and C-reactive protein (CRP) levels were additionally measured or recorded. Forty-five patients subsequently became septic and 44 did not. Soluble (s) E- and P-selectin levels, circulating PCT, SOFA score and diagnostic category were significantly different between the two groups. Multiple logistic regression analysis associated elevated sE- and sP-selectin levels and SOFA with an increased risk of developing sepsis, while multiple Cox regression analysis identified sE- and sP-selectin levels as the only parameters related to sepsis appearance with time [RR=1.026, 95%CI=1.008-1.045, p=0.005; RR=1.005 (by 10 units), 95%CI=1.000-1.010, p=0.034, respectively]. When trauma patients were independently analyzed, multiple Cox regression analysis revealed sE-selectin to be the only molecule associated with sepsis development with time (RR=1.041, 95%CI: 1.019-1.065; p<0.001). In conclusion, in our cohort of initially non-septic critically-ill patients, high levels of the circulating endothelial adhesion molecules E- and P-selectin, measured at ICU admission, appear to be associated with sepsis development in time.

Effects of various modes of mechanical ventilation in normal rats.

BACKGROUND: Recent studies in healthy mice and rats have reported that positive pressure ventilation delivered with physiological tidal volumes at normal end-expiratory volume worsens lung mechanics and induces cytokine release, thus suggesting that detrimental effects are due to positive pressure ventilation per se. The aim of this study in healthy animals is to assess whether these adverse outcomes depend on the mode of mechanical ventilation. METHODS: Rats were subjected to 4 h of spontaneous, positive pressure, and whole-body or thorax-only negative pressure ventilation (N = 8 per group). In all instances the ventilatory pattern was that of spontaneous breathing. Lung mechanics, cytokines concentration in serum and broncho-alveolar lavage fluid, lung wet-to-dry ratio, and histology were assessed. Values from eight animals euthanized shortly after anesthesia served as control. RESULTS: No evidence of mechanical ventilation-dependent lung injury was found in terms of lung mechanics, histology, or wet-to-dry ratio. Relative to control, cytokine levels and recruitment of polymorphonuclear leucocytes increased slightly, and to the same extent with spontaneous, positive pressure, and whole-body negative pressure ventilation. Thorax-only negative pressure ventilation caused marked chest and lung distortion, reversible increase of lung elastance, and higher polymorphonuclear leucocyte count and cytokine levels. CONCLUSION: Both positive and negative pressure ventilation performed with tidal volumes and timing of spontaneous, quiet breathing neither elicit an inflammatory response nor cause morpho-functional alterations in normal animals, thus supporting the notion of the presence of a critical volume threshold above which acute lung injury ensues. Distortion of lung parenchyma can induce an inflammatory response, even in the absence of volotrauma.

Pleural fluid glucose: A predictor of unsuccessful pleurodesis in a preselected cohort of patients with malignant pleural effusion.

PURPOSE: To assess whether exclusion of patients with conditions that could lead to large fluctuations of serum glucose, would increase the accuracy of pleural fluid glucose in predicting pleurodesis outcome in patients with malignant pleural effusion subjected to bleomycin pleurodesis. METHODS: A retrospective analysis of 162 patients with recurrent, symptomatic malignant pleural disease was performed. Patients with diabetes mellitus or other causes of hyperglycemia were excluded, as pleural fluid glucose has been reported to be sensitive to serum glucose fluctuations. Assessment of pleurodesis outcome was based on radiologic appearance 30 days post-bleomycin pleurodesis. RESULTS: Successful pleurodesis was achieved in 64.8% of patients. Univariate analysis showed that pleural fluid glucose (p<0.001), pH (p<0.001), total proteins (p<0.001), albumin (p<0.001) and cholesterol (p<0.05) were significantly lower in patients with pleurodesis failure, while LDH was significantly higher (p<0.05). Pleural fluid glucose was the only independent predictor of pleurodesis outcome and with a cut-off point of 65 mg/dl had a high sensitivity (90.7%) with an acceptable specificity (76.8%) (p<0.001). The regression model exhibiting the highest predictive accuracy included pleural fluid glucose and albumin (sensitivity 89.3%, specificity 84.5%, p<0.001). Furthermore, a product of glucose and albumin less than 152 could predict pleurodesis failure with 88.9% sensitivity and 82.8% specificity (p<0.001). CONCLUSIONS: Pleural glucose levels may reliably predict pleurodesis failure in patients without conditions that could lead to hyperglycemia, and its accuracy can increase if combined with pleural fluid albumin in an-easy-to calculate formula.

Strong ion gap and anion gap corrected for albumin and lactate in patients with sepsis in the intensive care unit.

INTRODUCTION: Metabolic acidosis is very common amongst critically ill sepsis patients partly due to the presence of unmeasured ions in serum. These ions can be detected by anion gap (AG) or strong ion gap (SIG) concentration values. The purpose of this study is to assess the correlation and potential agreement of the two methods in critically ill patients with sepsis. MATERIALS AND METHODS: The present is a retrospective study including septic patients admitted to the Intensive Care Unit from December 2014 to July 2016. The [SIG] and the [AG] corrected for albumin and lactate ([AGcl]) were calculated on admission and on sepsis remission or deterioration. The correlation of the two parameters was assessed in all patient groups using the Pearson correlation coefficient and linear regression analysis and the agreement with Bland-Altman plots. ROC survival curves were also generated for the patients in relation to the values of [AGcl], [SIG] and inorganic [SIG] ([SIGi]) on admission. RESULTS: There was a strong correlation linking [AGcl] and [SIG] values (r>0.9, P<0.05) in all patient groups. The results from all three linear regression equations were statistically significant as the models predicted the [AGcl] value from the [SIG] value with high accuracy. The mean difference of the two methods (i.e. [AGcl] - [SIG] in every patient separately) in septic patients on admission was 11.75 mEq/l with 95% limits of agreement [9.7-13.8]; in patients with sepsis deterioration, it was 11.8 mEq/l with 95% limits of agreement [9.8-13.7] and in patients with sepsis remission, it was 11.5 mEq/l with 95% limits of agreement [10.4-12.7]. ROC survival curves demonstrated a small area under the curve (AUC): [SIG] AUC: 0.479, 95% CI [0.351, 0.606], [SIGi] AUC: 0.581, 95% CI [0.457, 0.705], [AGcl] AUC: 0.529, 95% CI [0.401, 0.656]. CONCLUSION: [AGcl] and [SIG] demonstrate excellent correlation in septic patients, with a mean difference of about 12 mEq/l. Both parameters failed to demonstrate any predictive ability regarding patient mortality.

The Interaction of Complement and Intrinsic Coagulation System: A Comparative Study between COVID-19 and Bacterial Sepsis Patients.

Background/Objectives: Through the past several years, a constant interaction has been implicated between complement and coagulation cascades. SARS-CoV-2 infection and bacterial sepsis are potent activators of both cascades. This study aims to compare the extent of complement and intrinsic coagulation pathway activation (and the interplay between them) among patients with COVID-19 and bacterial sepsis. Methods: Serum and plasma samples were collected from 25 ICU patients (11 patients with COVID-19 and 14 patients with bacterial sepsis) at two time points (on admission and either on improvement or deterioration). The activities of coagulation factors XI and XII and complement factors C3a and C5a were measured at both time points. Results: The activities of factors XI and XII were increased in both groups of patients and at both time points. However, there were no statistically significant differences between SARS-CoV-2 and bacterial sepsis patients. On the other hand, both C3a and C5a were significantly higher in the COVID-19 group on admission. This correlation was preserved on reassessment. Conclusions: Complement activation seems to be more enhanced in COVID-19 than bacterial sepsis. However, the lack of statistical significance in factors XI and XII indicates t the presence of additional pathways for complement activation in SARS-CoV-2 infection.

ENaC gene variants and their involvement in Covid­19 severity.

Epidemiological studies report the association of diverse cardiovascular conditions with coronavirus disease 2019 (COVID-19), but the causality has remained to be established. Specific genetic factors and the extent to which they can explain variation in susceptibility or severity are largely elusive. The present study aimed to evaluate the link between 32 cardio-metabolic traits and COVID-19. A total of 60 participants were enrolled, who were categorized into the following 4 groups: A control group with no COVID-19 or any other underlying pathologies, a group of patients with a certain form of dyslipidemia and predisposition to atherosclerotic disease, a COVID-19 group with mild or no symptoms and a COVID-19 group with severe symptomatology hospitalized at the Intensive Care Unit of Sotiria Hospital (Athens, Greece). Demographic, clinical and laboratory data were recorded and genetic material was isolated, followed by simultaneous analysis of the genes related to dyslipidemia using a custom-made next-generation sequencing panel. In the COVID-19 group with mild or absent symptoms, the variant c.112C>T:p.P38S was detected in the sodium channel epithelial 1 subunit α (SCNN1A) gene, with a major allele frequency (Maf) of <0.01. In the COVID-19 group with severe symptoms, the variant c.786G>A:p.T262T was detected in the SCNN1B gene, which encodes for the ß-subunit of the epithelial sodium channel ENaC, with a Maf <0.01. None of the two rare variants were detected in the control or dyslipidemia groups. In conclusion, the current study suggests that ENaC variants are likely associated with genetic susceptibility to COVID-19, supporting the rationale for the risk and protective genetic factors for the morbidity and mortality of COVID-19.

Clinical Phenotyping for Prognosis and Immunotherapy Guidance in Bacterial Sepsis and COVID-19.

OBJECTIVES: It is suggested that sepsis may be classified into four clinical phenotypes, using an algorithm employing 29 admission parameters. We applied a simplified phenotyping algorithm among patients with bacterial sepsis and severe COVID-19 and assessed characteristics and outcomes of the derived phenotypes. DESIGN: Retrospective analysis of data from prospective clinical studies. SETTING: Greek ICUs and Internal Medicine departments. PATIENTS AND INTERVENTIONS: We analyzed 1498 patients, 620 with bacterial sepsis and 878 with severe COVID-19. We implemented a six-parameter algorithm (creatinine, lactate, aspartate transaminase, bilirubin, C-reactive protein, and international normalized ratio) to classify patients with bacterial sepsis intro previously defined phenotypes. Patients with severe COVID-19, included in two open-label immunotherapy trials were subsequently classified. Heterogeneity of treatment effect of anakinra was assessed. The primary outcome was 28-day mortality. MEASUREMENTS AND MAIN RESULTS: The algorithm validated the presence of the four phenotypes across the cohort of bacterial sepsis and the individual studies included in this cohort. Phenotype α represented younger patients with low risk of death, ß was associated with high comorbidity burden, and δ with the highest mortality. Phenotype assignment was independently associated with outcome, even after adjustment for Charlson Comorbidity Index. Phenotype distribution and outcomes in severe COVID-19 followed a similar pattern. CONCLUSIONS: A simplified algorithm successfully identified previously derived phenotypes of bacterial sepsis, which were predictive of outcome. This classification may apply to patients with severe COVID-19 with prognostic implications.

Clinical Phenotyping for Prognosis and Immunotherapy Guidance in Bacterial Sepsis and COVID-19.

OBJECTIVES: It is suggested that sepsis may be classified into four clinical phenotypes, using an algorithm employing 29 admission parameters. We applied a simplified phenotyping algorithm among patients with bacterial sepsis and severe COVID-19 and assessed characteristics and outcomes of the derived phenotypes. DESIGN: Retrospective analysis of data from prospective clinical studies. SETTING: Greek ICUs and Internal Medicine departments. PATIENTS AND INTERVENTIONS: We analyzed 1498 patients, 620 with bacterial sepsis and 878 with severe COVID-19. We implemented a six-parameter algorithm (creatinine, lactate, aspartate transaminase, bilirubin, C-reactive protein, and international normalized ratio) to classify patients with bacterial sepsis intro previously defined phenotypes. Patients with severe COVID-19, included in two open-label immunotherapy trials were subsequently classified. Heterogeneity of treatment effect of anakinra was assessed. The primary outcome was 28-day mortality. MEASUREMENTS AND MAIN RESULTS: The algorithm validated the presence of the four phenotypes across the cohort of bacterial sepsis and the individual studies included in this cohort. Phenotype α represented younger patients with low risk of death, ß was associated with high comorbidity burden, and δ with the highest mortality. Phenotype assignment was independently associated with outcome, even after adjustment for Charlson Comorbidity Index. Phenotype distribution and outcomes in severe COVID-19 followed a similar pattern. CONCLUSIONS: A simplified algorithm successfully identified previously derived phenotypes of bacterial sepsis, which were predictive of outcome. This classification may apply to patients with severe COVID-19 with prognostic implications.

Immune response to mycobacterial infection: lessons from flow cytometry.

Detecting and treating active and latent tuberculosis are pivotal elements for effective infection control; yet, due to their significant inherent limitations, the diagnostic means for these two stages of tuberculosis (TB) to date remain suboptimal. This paper reviews the current diagnostic tools for mycobacterial infection and focuses on the application of flow cytometry as a promising method for rapid and reliable diagnosis of mycobacterial infection as well as discrimination between active and latent TB: it summarizes diagnostic biomarkers distinguishing the two states of infection and also features of the distinct immune response against Mycobacterium tuberculosis (Mtb) at certain stages of infection as revealed by flow cytometry to date.

Inflammation and immune response in COPD: where do we stand?

Increasing evidence indicates that chronic inflammatory and immune responses play key roles in the development and progression of COPD. Recent data provide evidence for a role in the NLRP3 inflammasome in the airway inflammation observed in COPD. Cigarette smoke activates innate immune cells by triggering pattern recognition receptors (PRRs) to release "danger signal". These signals act as ligands to Toll-like receptors (TLRs), triggering the production of cytokines and inducing innate inflammation. In smokers who develop COPD there appears to be a specific pattern of inflammation in the airways and parenchyma as a result of both innate and adaptive immune responses, with the predominance of CD8+ and CD4+ cells, and in the more severe disease, with the presence of lymphoid follicles containing B lymphocytes and T cells. Furthermore, viral and bacterial infections interfere with the chronic inflammation seen in stable COPD and exacerbations via pathogen-associated molecular patterns (PAMPs). Finally, autoimmunity is another novel aspect that may play a critical role in the pathogenesis of COPD. This review is un update of the currently discussed roles of inflammatory and immune responses in the pathogenesis of COPD.

Tracheal resection in patients post-COVID-19 is associated with high reintervention rate and early restenosis.

Objectives: A remarkable increase in the number of patients presenting with tracheal complications after prolonged endotracheal intubation and mechanical ventilation for the management of the severe COVID-19-associated respiratory failure has been observed. In this study, we assessed the postoperative outcomes of tracheal resection in patients with COVID-19. Methods: We conducted a retrospective study in which all patients with a history of prolonged invasive mechanical ventilation due to COVID-19 infection, who were treated with tracheal resection and reconstruction, were included. The primary objective was in-hospital mortality and postoperative reintervention rate. The secondary objective was the time to tracheal restenosis. Results: During the 16-month study period, 11 patients with COVID-19 with tracheal complications underwent tracheal resection with end-to-end anastomosis. Mean patient age was 51.5 ± 9 years, and the majority were male (9 patients). Eight patients were referred for management of postintubation tracheal stenosis, and 3 patients were referred for tracheoesophageal fistula. Eight patients had a history of tracheostomy during the COVID-19 infection hospitalization. There was 1 in-hospital death (9.1%) due to septicemia in the intensive care unit approximately 2 months after the operation. Postoperatively, 32 reinterventions were required for tracheal restenosis due to granulation tissue formation. The risk for reintervention was higher during the first 3 months after the index operation. Four patients developed tracheal restenosis (36.4%), and 2 of them required endotracheal stent placement during the follow-up period. Conclusions: Tracheal resection and reconstruction after COVID-19 infection are associated with a high reintervention rate postoperatively. Such patients require close follow-up in expert interventional pulmonology units, and physicians should be on high alert for the early diagnosis and optimal management of tracheal restenosis.

The Real Impact of Age on Mortality in Critically Ill COVID-19 Patients.

OBJECTIVE: The impact of severe infection from COVID-19 and the resulting need for life support in an ICU environment is a fact that caused immense pressure in healthcare systems around the globe. Accordingly, elderly people faced multiple challenges, especially after admission to the ICU. On this basis, we performed this study to assess the impact of age on COVID-19 mortality in critically ill patients. MATERIALS AND METHODS: In this retrospective study, we collected data from 300 patients who were hospitalized in the ICU of a Greek respiratory hospital. We split patients into two age groups using a threshold of 65 years old. The primary objective of the study was the survival of patients in a follow up period of 60 days after their admission to the ICU. Secondary objectives were to determine whether mortality is affected by other factors, including sepsis and clinical and laboratory factors, Charlson Comorbidity Index (CCI), APACHE II and d-dimers, CRP, etc. Results: The survival of all patients in the ICU was 75.7%. Those in the <65 years old age group expressed a survival rate of 89.3%, whereas those in the ≥65 years old age group had a survival rate of 58% (p-value < 0.001). In the multivariate Cox regression, the presence of sepsis and an increased CCI were independent predictors of mortality in 60 days (p-value < 0.001), while the age group did not maintain its statistical significance (p-value = 0.320). CONCLUSIONS: Age alone as a simple number is not capable of predicting mortality in patients with severe COVID-19 in the ICU. We must use more composite clinical markers that may better reflect the biological age of patients, such as CCI. Moreover, the effective control of infections in the ICU is of utmost importance for the survival of patients, since avoiding septic complications can drastically improve the prognosis of all patients, regardless of age.

Modified SCOPE (mSCOPE) Score as a Tool to Predict Mortality in COVID-19 Critically Ill Patients.

INTRODUCTION: Efficient clinical scores predicting the outcome of severe COVID-19 pneumonia may play a pivotal role in patients' management. The aim of this study was to assess the modified Severe COvid Prediction Estimate score (mSCOPE) index as a predictor of mortality in patients admitted to the ICU due to severe COVID-19 pneumonia. MATERIALS AND METHODS: In this retrospective observational study, 268 critically ill COVID-19 patients were included. Demographic and laboratory characteristics, comorbidities, disease severity, and outcome were retrieved from the electronical medical files. The mSCOPE was also calculated. RESULTS: An amount of 70 (26.1%) of patients died in the ICU. These patients had higher mSCOPE score compared to patients who survived (p < 0.001). mSCOPE correlated to disease severity (p < 0.001) and to the number and severity of comorbidities (p < 0.001). Furthermore, mSCOPE significantly correlated with days on mechanical ventilation (p < 0.001) and days of ICU stay (p = 0.003). mSCOPE was found to be an independent predictor of mortality (HR:1.219, 95% CI: 1.010-1.471, p = 0.039), with a value ≥ 6 predicting poor outcome with a sensitivity (95%CI) 88.6%, specificity 29.7%, a positive predictive value of 31.5%, and a negative predictive value of 87.7%. CONCLUSION: mSCOPE score could be proved useful in patients' risk stratification, guiding clinical interventions in patients with severe COVID-19.