Writing Committee for the REMAP-CAP Investigators IMPORTANCE The evidence for benefit of convalescent plasma for critically ill patients with COVID-19 is inconclusive.OBJECTIVE To determine whether convalescent plasma would improve outcomes for critically ill adults with COVID-19. DESIGN, SETTING, AND PARTICIPANTSThe ongoing Randomized, Embedded, Multifactorial, Adaptive Platform Trial for Community-Acquired Pneumonia (REMAP-CAP) enrolled and randomized 4763 adults with suspected or confirmed COVID-19 between March 9, 2020, and January 18, 2021, within at least 1 domain; 2011 critically ill adults were randomized to open-label interventions in the immunoglobulin domain at 129 sites in 4 countries. Follow-up ended on April 19, 2021. INTERVENTIONSThe immunoglobulin domain randomized participants to receive 2 units of high-titer, ABO-compatible convalescent plasma (total volume of 550 mL ± 150 mL) within 48 hours of randomization (n = 1084) or no convalescent plasma (n = 916). MAIN OUTCOMES AND MEASURESThe primary ordinal end point was organ support-free days (days alive and free of intensive care unit-based organ support) up to day 21 (range, −1 to 21 days; patients who died were assigned -1 day). The primary analysis was an adjusted bayesian cumulative logistic model. Superiority was defined as the posterior probability of an odds ratio (OR) greater than 1 (threshold for trial conclusion of superiority >99%). Futility was defined as the posterior probability of an OR less than 1.2 (threshold for trial conclusion of futility >95%). An OR greater than 1 represented improved survival, more organ support-free days, or both. The prespecified secondary outcomes included in-hospital survival; 28-day survival; 90-day survival; respiratory support-free days; cardiovascular support-free days; progression to invasive mechanical ventilation, extracorporeal mechanical oxygenation, or death; intensive care unit length of stay; hospital length of stay; World Health Organization ordinal scale score at day 14; venous thromboembolic events at 90 days; and serious adverse events. RESULTS Among the 2011 participants who were randomized (median age, 61 [IQR, 52 to 70] years and 645/1998 [32.3%] women), 1990 (99%) completed the trial. The convalescent plasma intervention was stopped after the prespecified criterion for futility was met. The median number of organ support-free days was 0 (IQR, -1 to 16) in the convalescent plasma group and 3 (IQR, -1 to 16) in the no convalescent plasma group. The in-hospital mortality rate was 37.3% (401/1075) for the convalescent plasma group and 38.4% (347/904) for the no convalescent plasma group and the median number of days alive and free of organ support was 14 (IQR, 3 to 18) and 14 (IQR, 7 to 18), respectively. The median-adjusted OR was 0.97 (95% credible interval, 0.83 to 1.15) and the posterior probability of futility (OR <1.2) was 99.4% for the convalescent plasma group compared with the no convalescent plasma group. The treatment effects were consistent across the primary outcome and the 11...

European Union's Seventh Framework programme.

Objectives: Following surgery, it is difficult to distinguish a postoperative inflammatory reaction from infection. This study examined the predictive value of the biomarkers; procalcitonin, C-reactive protein, lactate, neutrophils, lymphocytes, platelets, and the biphasic activated partial thromboplastin time waveform in diagnosing bacterial infection following cardiac surgery. Design: Prospective, observational study. Setting: A regional, PICU in the United Kingdom. Patients: Three-hundred sixty-eight children under the age of 16 admitted to the PICU for elective cardiac surgery were enrolled in the study. Interventions: All biomarker measurements were determined daily until postoperative day 7. Children were assessed for postoperative infection until day 28 and divided into four groups: bacterial infection, culture-negative sepsis, viral infection, and no infection. We used the Kruskal-Wallis test, chi-square test, analysis of variance, and area under the curve in our analysis. Measurements and Main Results: In total, 71 of 368 children (19%) developed bacterial infection postoperatively, the majority being surgical site infections. In those with bacterial infection, procalcitonin was elevated on postoperative days 1–3 and the last measurement prior to event compared with those without bacterial infection. The most significant difference was the last measurement prior to event; 0.72 ng/mL in the bacterial infection group versus 0.13 ng/mL in the no infection group (for all groups; p < 0.001). Longitudinal profiles of all biomarkers were indistinct in the bacterial infection and nonbacterial infection groups except in those with culture-negative infections who had distinct procalcitonin kinetics on postoperative days 1–4. Children with culture-negative sepsis required longer ventilatory support and PICU stay and were more likely to develop complications than the other groups. Conclusions: None of the biomarkers studied within 3 days of infection distinguished between infection and postoperative inflammatory reaction. However, procalcitonin kinetics peaked on postoperative day 2 and fell more sharply than C-reactive protein kinetics, which peaked at postoperative day 3. The monitoring of procalcitonin kinetics following cardiac surgery may help guide rational antimicrobial use.

Sepsis, defined as life-threatening organ dysfunction caused by infection is difficult to distinguish clinically from infection or post-operative inflammation. We hypothesized that in a heterogeneous group of critically ill children, there would be different metabolic profiles between post-operative inflammation, bacterial and viral infection and infection with or without organ dysfunction. 1D 1H nuclear magnetic resonance spectra were acquired in plasma samples from critically ill children. We included children with bacterial (n = 25) and viral infection (n = 30) and controls (n = 58) (elective cardiac surgery without infection). Principal component analysis was used for data exploration and partial least squares discriminant analysis models for the differences between groups. Area under receiver operating characteristic curve (AUC) values were used to evaluate the models. Univariate analysis demonstrated differences between controls and bacterial and viral infection. There was excellent discrimination between bacterial and control (AUC = 0.94), and viral and control (AUC = 0.83), with slightly more modest discrimination between bacterial and viral (AUC = 0.78). There was modest discrimination (AUC = 0.73) between sepsis with organ dysfunction and infection with no organ dysfunction. In critically ill children, NMR metabolomics differentiates well between those with a post-operative inflammation but no infection, and those with infection (bacterial and viral), and between sepsis and infection.

Objective Bacterial Infections remains a leading cause of death in the Paediatric Intensive Care Unit (PICU). In this era of rising antimicrobial resistance, new tools are needed to guide antimicrobial use. The aim of this study was to investigate the accuracy of procalcitonin (PCT), neutrophil gelatinase-associated lipocalin (NGAL), resistin, activated partial thromboplastin time (aPTT) waveform and C-reactive protein (CRP) for the diagnosis of serious bacterial infection (SBI) in children on admission to PICU and their use as prognostic indicators. Setting A regional PICU in the United Kingdom. Patients Consecutive PICU admissions between October 2010 and June 2012. Measurements Blood samples were collected daily for biomarker measurement. The primary outcome measure was performance of study biomarkers for diagnosis of SBI on admission to PICU based on clinical, radiological and microbiological criteria. Secondary outcomes included durations of PICU stay and invasive ventilation and 28-day mortality. Patients were followed up to day 28 post-admission. Main results A total of 657 patients were included in the study. 92 patients (14%) fulfilled criteria for SBI. 28-day mortality was 2.6% (17/657), but 8.7% (8/92) for patients with SBI. The combination of PCT, resistin, plasma NGAL and CRP resulted in the greatest net reclassification improvement compared to CRP alone (0.69, p<0.005) with 10.5% reduction in correct classification of patients with SBI (p 0.52) but a 78% improvement in correct classification of patients without events (p <0.005). A statistical model of prolonged duration of PICU stay found log-transformed maximum values of biomarkers performed better than first recorded biomarkers. The final model included maximum values of CRP, plasma NGAL, lymphocyte and platelet count (AUC 79%, 95% CI 73.7% to 84.2%). Longitudinal profiles of biomarkers showed PCT levels to decrease most rapidly following admission SBI. Conclusion Combinations of biomarkers, including PCT, may improve accurate and timely identification of SBI on admission to PICU.