Continuation of chronic antiplatelet therapy is not associated with increased need for transfusions: a cohort study in critically ill septic patients.

BACKGROUND: The decision to maintain or halt antiplatelet medication in septic patients admitted to intensive care units presents a clinical dilemma. This is due to the necessity to balance the benefits of preventing thromboembolic incidents and leveraging anti-inflammatory properties against the increased risk of bleeding. METHODS: This study involves a secondary analysis of data from a prospective cohort study focusing on patients diagnosed with severe sepsis or septic shock. We evaluated the outcomes of 203 patients, examining mortality rates and the requirement for transfusion. The cohort was divided into two groups: those whose antiplatelet therapy was sustained (n = 114) and those in whom it was discontinued (n = 89). To account for potential biases such as indication for antiplatelet therapy, propensity score matching was employed. RESULTS: Therapy continuation did not significantly alter transfusion requirements (discontinued vs. continued in matched samples: red blood cell concentrates 51.7% vs. 68.3%, p = 0.09; platelet concentrates 21.7% vs. 18.3%, p = 0.82; fresh frozen plasma concentrates 38.3% vs. 33.3%, p = 0.7). 90-day survival was higher within the continued group (30.0% vs. 70.0%; p < 0.001) and the Log-rank test (7-day survivors; p = 0.001) as well as Cox regression (both matched samples) suggested an association between continuation of antiplatelet therapy < 7 days and survival (HR: 0.24, 95%-CI 0.10 to 0.63, p = 0.004). Sepsis severity expressed by the SOFA score did not differ significantly in matched and unmatched patients (both p > 0.05). CONCLUSIONS: The findings suggest that continuing antiplatelet therapy in septic patients admitted to intensive care units could be associated with a significant survival benefit without substantially increasing the need for transfusion. These results highlight the importance of a nuanced approach to managing antiplatelet medication in the context of severe sepsis and septic shock.

Machine learning identifies ICU outcome predictors in a multicenter COVID-19 cohort.

BACKGROUND: Intensive Care Resources are heavily utilized during the COVID-19 pandemic. However, risk stratification and prediction of SARS-CoV-2 patient clinical outcomes upon ICU admission remain inadequate. This study aimed to develop a machine learning model, based on retrospective & prospective clinical data, to stratify patient risk and predict ICU survival and outcomes. METHODS: A Germany-wide electronic registry was established to pseudonymously collect admission, therapeutic and discharge information of SARS-CoV-2 ICU patients retrospectively and prospectively. Machine learning approaches were evaluated for the accuracy and interpretability of predictions. The Explainable Boosting Machine approach was selected as the most suitable method. Individual, non-linear shape functions for predictive parameters and parameter interactions are reported. RESULTS: 1039 patients were included in the Explainable Boosting Machine model, 596 patients retrospectively collected, and 443 patients prospectively collected. The model for prediction of general ICU outcome was shown to be more reliable to predict "survival". Age, inflammatory and thrombotic activity, and severity of ARDS at ICU admission were shown to be predictive of ICU survival. Patients' age, pulmonary dysfunction and transfer from an external institution were predictors for ECMO therapy. The interaction of patient age with D-dimer levels on admission and creatinine levels with SOFA score without GCS were predictors for renal replacement therapy. CONCLUSIONS: Using Explainable Boosting Machine analysis, we confirmed and weighed previously reported and identified novel predictors for outcome in critically ill COVID-19 patients. Using this strategy, predictive modeling of COVID-19 ICU patient outcomes can be performed overcoming the limitations of linear regression models. Trial registration "ClinicalTrials" (clinicaltrials.gov) under NCT04455451.

Anti-platelet factor 4 antibodies causing VITT do not cross-react with SARS-CoV-2 spike protein.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe adverse effect of ChAdOx1 nCoV-19 COVID-19 vaccine (Vaxzevria) and Janssen Ad26.COV2.S COVID-19 vaccine, and it is associated with unusual thrombosis. VITT is caused by anti-platelet factor 4 (PF4) antibodies activating platelets through their FcγRIIa receptors. Antibodies that activate platelets through FcγRIIa receptors have also been identified in patients with COVID-19. These findings raise concern that vaccination-induced antibodies against anti-SARS-CoV-2 spike protein cause thrombosis by cross-reacting with PF4. Immunogenic epitopes of PF4 and SARS-CoV-2 spike protein were compared using in silico prediction tools and 3D modeling. The SARS-CoV-2 spike protein and PF4 share at least 1 similar epitope. Reactivity of purified anti-PF4 antibodies from patients with VITT was tested against recombinant SARS-CoV-2 spike protein. However, none of the affinity-purified anti-PF4 antibodies from 14 patients with VITT cross-reacted with SARS-CoV-2 spike protein. Sera from 222 polymerase chain reaction-confirmed patients with COVID-19 from 5 European centers were tested by PF4-heparin enzyme-linked immunosorbent assays and PF4-dependent platelet activation assays. We found anti-PF4 antibodies in sera from 19 (8.6%) of 222 patients with COVID-19. However, only 4 showed weak to moderate platelet activation in the presence of PF4, and none of those patients developed thrombotic complications. Among 10 (4.5%) of 222 patients who had COVID-19 with thrombosis, none showed PF4-dependent platelet-activating antibodies. In conclusion, antibodies against PF4 induced by vaccination do not cross-react with the SARS-CoV-2 spike protein, indicating that the intended vaccine-induced immune response against SARS-CoV-2 spike protein is not the trigger of VITT. PF4-reactive antibodies found in patients with COVID-19 in this study were not associated with thrombotic complications.

Do Sepsis-3 Criteria Facilitate Earlier Recognition of Sepsis and Septic Shock? A Retrospective Cohort Study.

BACKGROUND: New Sepsis-3 criteria are supposed to "facilitate earlier recognition … of patients with sepsis." To test this, we performed novel and direct comparisons of Sepsis-1 vs. Sepsis-3 criteria with respect to time differences of sepsis onset. METHODS: In a cohort of intensive care unit (ICU) patients prospectively diagnosed with severe sepsis or septic shock according to Sepsis-1 criteria between 01/2010 and 12/2015, the time differences between meeting Sepsis-1 vs. Sepsis-3 criteria as time of sepsis onset and the corresponding differences in illness severity were tested. Similar comparisons were performed for septic shock subset meeting different Sepsis-1 vs. Sepsis-3 criteria. Patients with non-ICU-acquired sepsis and patients with sepsis onset more than 48 h postadmission (ICU-acquired sepsis) were analyzed separately to account for differences in availability of routinely collected organ dysfunction data. RESULTS: A total of 10,905 ICU patients were screened; 862 patients met Sepsis-1 criteria, of whom 834 (97%) also met Sepsis-3 criteria. In patients, admitted to the ICU with sepsis, Sepsis-3 criteria compared with Sepsis-1 criteria were more frequently fulfilled within the first 3 h (84% vs. 75%, P < 0.001).In patients with ICU-acquired sepsis, sepsis onset was in 50% at least 1 day earlier after application of Sepsis-3 (P = 0.011). These patients were systemic inflammatory response syndrome negative at the earlier sepsis onset, but suffered already from organ dysfunction. Sepsis-3 criteria were timely in 86% and 1 day delayed in 7%. Only 7% (8 patients) did not meet Sepsis-3 criteria in this group. These patients had already an increased SOFA score and did develop neither a further increase nor the new septic shock criteria. Classification according to Sepsis-3 reduced the proportion of septic shock (51% vs. 75%, P < 0.001).Twenty-eight-day mortality was 38% for new septic shock compared with 33% of Sepsis-1 septic shock (P > 0.05). Patients not detected by Sepsis-3 had a 28-day mortality of 11%. CONCLUSIONS: Sepsis-3 criteria facilitate an earlier and more predictive recognition of sepsis and septic shock in patients with non-ICU and ICU-acquired sepsis primarily diagnosed by Sepsis-1 criteria. These results require further validation with prospectively collected data.

Quality Improvement Initiative for Severe Sepsis and Septic Shock Reduces 90-Day Mortality: A 7.5-Year Observational Study.

OBJECTIVE: To investigate the impact of a quality improvement initiative for severe sepsis and septic shock focused on the resuscitation bundle on 90-day mortality. Furthermore, effects on compliance rates for antiinfective therapy within the recommended 1-hour interval are evaluated. DESIGN: Prospective observational before-after cohort study. SETTING: Tertiary university hospital in Germany. PATIENTS: All adult medical and surgical ICU patients with severe sepsis and septic shock. INTERVENTION: Implementation of a quality improvement program over 7.5 years. MEASUREMENTS: The primary endpoint was 90-day mortality. Secondary endpoints included ICU and hospital mortality rates and length of stay, time to broad-spectrum antiinfective therapy, and compliance with resuscitation bundle elements. MAIN RESULTS: A total of 14,115 patients were screened. The incidence of severe sepsis and septic shock was 9.7%. Ninety-day mortality decreased from 64.2% to 45.0% (p < 0.001). Hospital length of stay decreased from 44 to 36 days (p < 0.05). Compliance with resuscitation bundle elements was significantly improved. Antibiotic therapy within the first hour after sepsis onset increased from 48.5% to 74.3% (p < 0.001). Multivariate analysis revealed blood cultures before antibiotic therapy (hazard ratio, 0.60-0.84; p < 0.001), adequate calculated antibiotic therapy (hazard ratio, 0.53-0.75; p < 0.001), 1-2 L crystalloids within the first 6 hours (hazard ratio 0.67-0.97; p = 0.025), and greater than or equal to 6 L during the first 24 hours (hazard ratio, 0.64-0.95; p = 0.012) as predictors for improved survival. CONCLUSIONS: The continuous quality improvement initiative focused on the resuscitation bundle was associated with increased compliance and a persistent reduction in 90-day mortality over a 7.5-year period. Based on the observational study design, a causal relationship cannot be proven, and respective limitations need to be considered.