Impact of immunosuppressive regimen on ICU acquired pneumonia in critically ill COVID-19.

BACKGROUND: Immunosuppressors (IS) such as Dexamethasone (DXM), Tocilizumab, and high-dose methylprednisolone boli (HDMB), are used in COVID-19-related acute respiratory distress syndrome (ARDS). This study aimed to determine whether COVID-19 ARDS-related combined IS therapy was associated with an increased incidence of ICU-acquired pneumonia (IAP). METHODS: We retrospectively analyzed COVID-19-ARDS admitted to ICU from March 2020 to April 2022. Patients' and IAP characteristics were analyzed according to five IS regimens: No IS, DXM alone, DXM+HDMB, DXM+tocilizumab, and DXM+tocilizumab+HDMB. To investigate the role of IS on IAP incidence, we performed a multivariate logistic regression and built a propensity score. Ultimately, we used a conditional logistic regression after pairing on the propensity score. RESULTS: The study included 496 COVID-19-ARDS. Regarding the IS therapy, 12.7% received no IS, 43% DXM alone, 21.6% DXM+HDMB, 15.5% DXM+tocilizumab and 5.4% DXM+tocilizumab+HDMB. 37% presented at least one IAP, and the IAP incidence was higher with DXM+HDMB (66.4%) compared to no IS (P<0.0001), DXM (P<0.0001) and DXM+tocilizumab (P<0.0001). HDMB and probabilistic antibiotherapy at admission were independent IAP predictors after adjustment on the propensity score (respectively OR:2.44; P<0.0001 and OR:2.85; P<0.001). CONCLUSIONS: In critically ill COVID-19, HDMB significantly increases the risk of IAP whereas DXM alone, nor in combination with tocilizumab, did not.

Effects of Standard-Dose Prophylactic, High-Dose Prophylactic, and Therapeutic Anticoagulation in Patients With Hypoxemic COVID-19 Pneumonia: The ANTICOVID Randomized Clinical Trial.

Importance: Given the high risk of thrombosis and anticoagulation-related bleeding in patients with hypoxemic COVID-19 pneumonia, identifying the lowest effective dose of anticoagulation therapy for these patients is imperative. Objectives: To determine whether therapeutic anticoagulation (TA) or high-dose prophylactic anticoagulation (HD-PA) decreases mortality and/or disease duration compared with standard-dose prophylactic anticoagulation (SD-PA), and whether TA outperforms HD-PA; and to compare the net clinical outcomes among the 3 strategies. Design, Settings, and Participants: The ANTICOVID randomized clinical open-label trial included patients with hypoxemic COVID-19 pneumonia requiring supplemental oxygen and having no initial thrombosis on chest computer tomography with pulmonary angiogram at 23 health centers in France from April 14 to December 13, 2021. Of 339 patients randomized, 334 were included in the primary analysis-114 patients in the SD-PA group, 110 in the HD-PA, and 110 in the TA. At randomization, 90% of the patients were in the intensive care unit. Data analyses were performed from April 13, 2022, to January 3, 2023. Interventions: Patients were randomly assigned (1:1:1) to receive either SD-PA, HD-PA, or TA with low-molecular-weight or unfractionated heparin for 14 days. Main Outcomes and Measures: A hierarchical criterion of all-cause mortality followed by time to clinical improvement at day 28. Main secondary outcome was net clinical outcome at day 28 (composite of thrombosis, major bleeding, and all-cause death). Results: Among the study population of 334 individuals (mean [SD] age, 58.3 [13.0] years; 226 [67.7%] men and 108 [32.3%] women), use of HD-PA and SD-PA had similar probabilities of favorable outcome (47.3% [95% CI, 39.9% to 54.8%] vs 52.7% [95% CI, 45.2% to 60.1%]; P = .48), as did TA compared with SD-PA (50.9% [95% CI, 43.4% to 58.3%] vs 49.1% [95% CI, 41.7% to 56.6%]; P = .82) and TA compared with HD-PA (53.5% [95% CI 45.8% to 60.9%] vs 46.5% [95% CI, 39.1% to 54.2%]; P = .37). Net clinical outcome was met in 29.8% of patients receiving SD-PA (20.2% thrombosis, 2.6% bleeding, 14.0% death), 16.4% receiving HD-PA (5.5% thrombosis, 3.6% bleeding, 11.8% death), and 20.0% receiving TA (5.5% thrombosis, 3.6% bleeding, 12.7% death). Moreover, HD-PA and TA use significantly reduced thrombosis compared with SD-PA (absolute difference, -14.7 [95% CI -6.2 to -23.2] and -14.7 [95% CI -6.2 to -23.2], respectively). Use of HD-PA significantly reduced net clinical outcome compared with SD-PA (absolute difference, -13.5; 95% CI -2.6 to -24.3). Conclusions and Relevance: This randomized clinical trial found that compared with SD-PA, neither HD-PA nor TA use improved the primary hierarchical outcome of all-cause mortality or time to clinical improvement in patients with hypoxemic COVID-19 pneumonia; however, HD-PA resulted in significantly better net clinical outcome by decreasing the risk of de novo thrombosis. Trial Registration: ClinicalTrials.gov Identifier: NCT04808882.

Impact of corticosteroids on the procoagulant profile of critically ill COVID-19 patients: a before-after study.

BACKGROUND: Several studies have reported an increased risk of thrombotic events in COVID-19 patients, but the pathophysiology of this procoagulant phenotype remains poorly understood. We hypothesized that corticosteroids may attenuate this procoagulant state through their anti-inflammatory effects. The aim of this study was to evaluate the impact of dexamethasone (DXM) on the coagulation profile of severely-ill COVID-19 patients METHODS: We conducted a retrospective, observational before/after bi-centric cohort study among ICU patients hospitalized for severe COVID-19 and receiving therapeutic anticoagulation by unfractionated heparin (UFH). Before and after the standardized use of DXM, we compared inflammatory and coagulation profiles, as well as the kinetics of heparin requirement, adjusted for weight and anti-Xa activity. RESULTS: Eighty-six patients were included, 35 in the no-DXM group, and 51 in the DXM group. At admission, CRP and fibrinogen levels were not different between groups, neither were UFH infusion rates. At day 3 after ICU admission, CRP (178 ± 94 mg/L vs 99± 68 mg/L, p<0.001) and fibrinogen (7.2 ± 1.4 g/L vs 6.1 ± 1.4 g/L, p=0.001) significantly decreased in the DXM group, but not in the no-DXM group. Over time, UFH infusion rates were lower in the DXM group (p<0.001) without any significant difference in plasma anti-Xa activity. CRP variations correlated with heparin dose variations between Day 0 and Day 3 (r=0.39, p=0.009). Finally, the incidence of venous thromboembolic events during in-ICU stay was significantly reduced in the DXM group (4 vs. 43%, p<0.0001). CONCLUSIONS: In critically ill COVID-19 patients, dexamethasone use was associated with a decrease in both pro-inflammatory and procoagulant profile.

Auto-antibodies against type I IFNs in > 10% of critically ill COVID-19 patients: a prospective multicentre study.

BACKGROUND: Auto-antibodies (auto-Abs) neutralizing type I interferons (IFN) have been found in about 15% of critical cases COVID-19 pneumonia and less than 1% of mild or asymptomatic cases. Determining whether auto-Abs influence presentation and outcome of critically ill COVID-19 patients could lead to specific therapeutic interventions. Our objectives were to compare the severity at admission and the mortality of patients hospitalized for critical COVID-19 in ICU with versus without auto-Abs. RESULTS: We conducted a prospective multicentre cohort study including patients admitted in 11 intensive care units (ICUs) from Great Paris area hospitals with proven SARS-CoV-2 infection and acute respiratory failure. 925 critically ill COVID-19 patients were included. Auto-Abs neutralizing type I IFN-α2, ß and/or ω were found in 96 patients (10.3%). Demographics and comorbidities did not differ between patients with versus without auto-Abs. At ICU admission, Auto-Abs positive patients required a higher FiO2 (100% (70-100) vs. 90% (60-100), p = 0.01), but were not different in other characteristics. Mortality at day 28 was not different between patients with and without auto-Abs (18.7 vs. 23.7%, p = 0.279). In multivariable analysis, 28-day mortality was associated with age (adjusted odds ratio (aOR) = 1.06 [1.04-1.08], p < 0.001), SOFA score (aOR = 1.18 [1.12-1.23], p < 0.001) and immunosuppression (aOR = 1.82 [1.1-3.0], p = 0.02), but not with the presence of auto-Abs (aOR = 0.69 [0.38-1.26], p = 0.23). CONCLUSIONS: In ICU patients, auto-Abs against type I IFNs were found in at least 10% of patients with critical COVID-19 pneumonia. They were not associated with day 28 mortality.

Impairment of neutrophil functions and homeostasis in COVID-19 patients: association with disease severity.

BACKGROUND: A dysregulated immune response is emerging as a key feature of critical illness in COVID-19. Neutrophils are key components of early innate immunity that, if not tightly regulated, contribute to uncontrolled systemic inflammation. We sought to decipher the role of neutrophil phenotypes, functions, and homeostasis in COVID-19 disease severity and outcome. METHODS: By using flow cytometry, this longitudinal study compares peripheral whole-blood neutrophils from 90 COVID-19 ICU patients with those of 22 SARS-CoV-2-negative patients hospitalized for severe community-acquired pneumonia (CAP) and 38 healthy controls. We also assessed correlations between these phenotypic and functional indicators and markers of endothelial damage as well as disease severity. RESULTS: At ICU admission, the circulating neutrophils of the COVID-19 patients showed continuous basal hyperactivation not seen in CAP patients, associated with higher circulating levels of soluble E- and P-selectin, which reflect platelet and endothelial activation. Furthermore, COVID-19 patients had expanded aged-angiogenic and reverse transmigrated neutrophil subsets-both involved in endothelial dysfunction and vascular inflammation. Simultaneously, COVID-19 patients had significantly lower levels of neutrophil oxidative burst in response to bacterial formyl peptide. Moreover patients dying of COVID-19 had significantly higher expansion of aged-angiogenic neutrophil subset and greater impairment of oxidative burst response than survivors. CONCLUSIONS: These data suggest that neutrophil exhaustion may be involved in the pathogenesis of severe COVID-19 and identify angiogenic neutrophils as a potentially harmful subset involved in fatal outcome.

Endotracheal intubation rate is lower with additional face-mask noninvasive ventilation for critically-ill SARS-CoV-2 patients requiring high-flow nasal oxygen: a retrospective bicentric cohort with propensity score analysis.

BACKGROUND: SARS-CoV-2 pneumonia is responsible for unprecedented numbers of acute respiratory failure requiring invasive mechanical ventilation (IMV). This work aimed to assess whether adding face-mask noninvasive ventilation (NIV) to high-flow nasal oxygen (HFNO) was associated with a reduced need for endotracheal intubation. METHODS: This retrospective cohort study was conducted from July 2020 to January 2021 in two tertiary care intensive care units (ICUs) in Paris, France. Patients admitted for laboratory confirmed SARS-CoV-2 infection with acute hypoxemic respiratory failure requiring HFNO with or without NIV were included. The primary outcome was the rate of endotracheal intubation. Secondary outcomes included day-28 mortality, day-28 respiratory support and IMV free days, ICU and hospital length-of-stay. Sensitivity analyses with both propensity score matching and overlap weighting were used. RESULTS: One hundred twenty-eight patients were included, 88 (69%) received HFNO alone and 40 (31%) received additional NIV. Additional NIV was associated with a reduced rate of endotracheal intubation in multivariate analysis (53 [60%] vs. 15 [38%], HR=0.46 [95% CI: 0.23-0.95], P=0.04). Sensitivity analyses by propensity score matching (HR=0.45 [95% CI: 0.24-0.84], P=0.01) and overlap weighting (HR=0.52 [95% CI: 0.28-0.94], P=0.03) were consistent. Day-28 mortality was 25 (28%) in the HFNO group and 8 (20%) in the NIV group (HR=0.75 [95% CI: 0.15-3.82], P=0.72). NIV was associated with higher IMV free days (20 [0-28] vs. 28 [14-28], P=0.015). All sensitivity analyses were consistent regarding secondary outcomes. CONCLUSIONS: Need for endotracheal intubation was lower in critically-ill SARS-CoV-2 patients receiving face-mask noninvasive mechanical ventilation in addition to high-flow oxygen therapy.

Impaired skin microvascular endothelial reactivity in critically ill COVID-19 patients.

BACKGROUND: Some clinical and histological studies have reported that SARS-CoV-2 infection may damage the endothelium. However, the impact of this virus on endothelial function in vivo remains poorly characterized. In this single-center pilot observational study, we performed iontophoresis of acetylcholine coupled with Laser doppler to investigate microvascular endothelial reactivity in COVID-19 patients compared to patients with non-COVID-19 bacterial pneumonia (NCBP) patients. RESULTS: During three consecutive months, 32 COVID-19 patients and 11 control NCBP patients with acute respiratory failure were included. The median age was 59 [50-68] and 69 [57-75] years in COVID-19 and NCBP groups, respectively (P = 0.11). There was no significant difference in comorbidities or medications between the two groups, except for body mass index, which was higher in COVID-19 patients. NCBP patients had a higher SAPS II score compared to COVID-19 patients (P < 0.0001), but SOFA score was not different between groups (P = 0.51). Global hemodynamic and peripheral tissue perfusion parameters were not different between groups. COVID-19 patients had significantly lower skin microvascular basal blood flow than NCBP patients (P = 0.02). In addition, endothelium-dependent microvascular reactivity was threefold lower in COVID-19 patients than NCBP patients (P = 0.008). CONCLUSIONS: Both baseline skin microvascular blood flow and skin endothelial-dependent microvascular reactivity were impaired in critically ill COVID-19 patients compared to NCBP patients, despite a lower disease severity score supporting a specific pathogenic role of SARS-CoV-2 on the endothelium.

Comparison of standard prophylactic, intermediate prophylactic and therapeutic anticoagulation in patients with severe COVID-19: protocol for the ANTICOVID multicentre, parallel-group, open-label, randomised controlled trial.

INTRODUCTION: COVID-19 induces venous, arterial and microvascular thrombosis, involving several pathophysiological processes. In patients with severe COVID-19 without macrovascular thrombosis, escalating into high-dose prophylactic anticoagulation (HD-PA) or therapeutic anticoagulation (TA) could be beneficial in limiting the extension of microvascular thrombosis and forestalling the evolution of lung and multiorgan microcirculatory dysfunction. In the absence of data from randomised trials, clinical practice varies widely. METHODS AND ANALYSIS: This is a French multicentre, parallel-group, open-label, randomised controlled superiority trial to compare the efficacy and safety of three anticoagulation strategies in patients with COVID-19. Patients with oxygen-treated COVID-19 showing no pulmonary artery thrombosis on computed tomography with pulmonary angiogram will be randomised to receive either low-dose PA, HD-PA or TA for 14 days. Patients attaining the extremes of weight and those with severe renal failure will not be included. We will recruit 353 patients. Patients will be randomised on a 1:1:1 basis, and stratified by centre, use of invasive mechanical ventilation, D-dimer levels and body mass index. The primary endpoint is a hierarchical criterion at day 28 including all-cause mortality, followed by the time to clinical improvement defined as the time from randomisation to an improvement of at least two points on the ordinal clinical scale. Secondary outcomes include thrombotic and major bleeding events at day 28, individual components of the primary endpoint, number of oxygen-free, ventilator-free and vasopressor-free days at day 28, D-dimer and sepsis-induced coagulopathy score at day 7, intensive care unit and hospital stay at day 28 and day 90, and all-cause death and quality of life at day 90. ETHICS AND DISSEMINATION: The study has been approved by an ethical committee (Ethics Committee, Ile de France VII, Paris, France; reference 2020-A03531-38). Patients will be included after obtaining their signed informed consent. The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04808882.

Elevated plasma IL-6 and CRP levels are associated with adverse clinical outcomes and death in critically ill SARS-CoV-2 patients: inflammatory response of SARS-CoV-2 patients.

BACKGROUND: SARS coronavirus 2 (SARS-CoV-2) is responsible for high morbidity and mortality worldwide, mostly due to the exacerbated inflammatory response observed in critically ill patients. However, little is known about the kinetics of the systemic immune response and its association with survival in SARS-CoV-2+ patients admitted in ICU. We aimed to compare the immuno-inflammatory features according to organ failure severity and in-ICU mortality. METHODS: Six-week multicentre study (N = 3) including SARS-CoV-2+ patients admitted in ICU. Analysis of plasma biomarkers at days 0 and 3-4 according to organ failure worsening (increase in SOFA score) and 60-day mortality. RESULTS: 101 patients were included. Patients had severe respiratory diseases with PaO2/FiO2 of 155 [111-251] mmHg), SAPS II of 37 [31-45] and SOFA score of 4 [3-7]. Eighty-three patients (83%) required endotracheal intubation/mechanical ventilation and among them, 64% were treated with prone position. IL-1ß was barely detectable. Baseline IL-6 levels positively correlated with organ failure severity. Baseline IL-6 and CRP levels were significantly higher in patients in the worsening group than in the non-worsening group (278 [70-622] vs. 71 [29-153] pg/mL, P < 0.01; and 178 [100-295] vs. 100 [37-213] mg/L, P < 0.05, respectively). Baseline IL-6 and CRP levels were significantly higher in non-survivors compared to survivors but fibrinogen levels and lymphocyte counts were not different between groups. After adjustment on SOFA score and time from symptom onset to first dosage, IL-6 and CRP remained significantly associated with mortality. IL-6 changes between Day 0 and Day 3-4 were not different according to the outcome. A contrario, kinetics of CRP and lymphocyte count were different between survivors and non-survivors. CONCLUSIONS: In SARS-CoV-2+ patients admitted in ICU, a systemic pro-inflammatory signature was associated with clinical worsening and 60-day mortality.