Abstract

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 PARTICIPANTS The 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. INTERVENTIONS The 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 MEASURES The 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 secondary outcomes. Serious adverse events were reported in 3.0% (32/1075) of participants in the convalescent plasma group and in 1.3% (12/905) of participants in the no convalescent plasma group. CONCLUSIONS AND RELEVANCE Among critically ill adults with confirmed COVID-19, treatment with 2 units of high-titer, ABO-compatible convalescent plasma had a low likelihood of providing improvement in the number of organ support-free days. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT02735707.

Abstract

BACKGROUND Anaemia is common and associated with poor outcomes in survivors of critical illness. However, the optimal treatment strategy is unclear. METHODS We conducted a multicentre, feasibility RCT to compare either a single dose of ferric carboxymaltose 1000 mg i.v. or usual care in patients being discharged from the ICU with moderate or severe anaemia (haemoglobin ≤100 g L(-1)). We collected data on feasibility (recruitment, randomisation, follow-up), biological efficacy, and clinical outcomes. RESULTS Ninety-eight participants were randomly allocated (49 in each arm). The overall recruitment rate was 34% with 6.5 participants recruited on average per month. Forty-seven of 49 (96%) participants received the intervention. Patient-reported outcome measures were available for 79/93 (85%) survivors at 90 days. Intravenous iron resulted in a higher mean (standard deviation [sd]) haemoglobin at 28 days (119.8 [13.3] vs 106.7 [14.9] g L(-1)) and 90 days (130.5 [15.1] vs 122.7 [17.3] g L(-1)), adjusted mean difference (10.98 g L(-1); 95% confidence interval [CI], 4.96-17.01; P<0.001) over 90 days after randomisation. Infection rates were similar in both groups. Hospital readmissions at 90 days post-ICU discharge were lower in the i.v. iron group (7/40 vs 15/39; risk ratio=0.46; 95% CI, 0.21-0.99; P=0.037). The median (inter-quartile range) post-ICU hospital stay was shorter in the i.v. iron group but did not reach statistical significance (5.0 [3.0-13.0] vs 9.0 [5.0-16.0] days, P=0.15). CONCLUSION A large, multicentre RCT of i.v. iron to treat anaemia in survivors of critical illness appears feasible and is necessary to determine the effects on patient-centred outcomes. CLINICAL TRIAL REGISTRATION ISRCTN13721808 (www.isrctn.com).

Abstract

BACKGROUND At present, red blood cells (RBCs) are stored for up to 42 days prior to transfusion. The relative effectiveness and safety of different RBC storage times prior to transfusion is uncertain. OBJECTIVE To assess the clinical effectiveness and cost-effectiveness of transfusing fresher RBCs (stored for ≤ 7 days) compared with current standard-aged RBCs in critically ill patients requiring blood transfusions. DESIGN The international Age of BLood Evaluation (ABLE) trial was a multicentre, randomised, blinded trial undertaken in Canada, the UK, the Netherlands and France. The UK trial was funded to contribute patients to the international trial and undertake a UK-specific health economic evaluation. SETTING Twenty intensive care units (ICUs) in the UK, as part of 64 international centres. PARTICIPANTS Critically ill patients aged ≥ 18 years (≥ 16 years in Scotland) expected to require mechanical ventilation for ≥ 48 hours and requiring a first RBC transfusion during the first 7 days in the ICU. INTERVENTIONS All decisions to transfuse RBCs were made by clinicians. One patient group received exclusively fresh RBCs stored for ≤ 7 days whenever transfusion was required from randomisation until hospital discharge. The other group received standard-issue RBCs throughout their hospital stay. MAIN OUTCOME MEASURES The primary outcome was 90-day mortality. Secondary outcomes included development of organ dysfunction, new thrombosis, infections and transfusion reactions. The primary economic evaluation was a cost-utility analysis. RESULTS The international trial took place between March 2009 and October 2014 (UK recruitment took place between January 2012 and October 2014). In total, 1211 patients were assigned to receive fresh blood and 1219 patients to receive standard-aged blood. RBCs were stored for a mean of 6.1 days [standard deviation (SD) +/- 4.9 days] in the group allocated to receive fresh blood and 22.0 days (SD +/- 8.4 days) in the group allocated to receive standard-aged blood. Patients received a mean of 4.3 RBC units (SD +/- 5.2 RBC units) and 4.3 RBC units (SD +/- 5.5 RBC units) in the groups receiving fresh blood and standard-aged blood, respectively. At 90 days, 37.0% of patients in the group allocated to receive fresh blood and 35.3% of patients in the group allocated to receive standard-aged blood had died {absolute risk difference 1.7% [95% confidence interval (CI) -2.1% to 5.5%]}. There were no between-group differences in any secondary outcomes. The UK cohort comprised 359 patients randomised and followed up for 12 months for the cost-utility analysis. UK patients had similar characteristics and outcomes to the international cohort. Mean total costs per patient were pound32,346 (95% CI pound29,306 to pound35,385) in the group allocated to receive fresh blood and pound33,353 (95% CI pound29,729 to pound36,978) in the group allocated to receive standard-aged blood. Approximately 85% of the total costs were incurred during the index hospital admission. There were no significant cost differences between the two groups [mean incremental costs for those receiving fresh vs. standard-aged blood: - pound231 (95% CI - pound4876 to pound4415)], nor were there significant differences in outcomes (mean difference in quality-adjusted life-years -0.010, 95% CI -0.078 to 0.057). LIMITATIONS Adverse effects from the exclusive use of older RBCs compared with standard or fresh RBCs cannot be excluded. CONCLUSIONS The use of RBCs aged ≤ 7 days confers no clinical or economic benefit in critically ill patients compared with standard-aged RBCs. FUTURE WORK Future studies should address the safety of RBCs near the end of the current permitted storage age. TRIAL REGISTRATION Current Controlled Trials ISRCTN44878718. FUNDING This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 62. See the NIHR Journals Library website for further project information. The

Abstract

OBJECTIVE To compare patient outcomes of restrictive versus liberal blood transfusion strategies in patients with cardiovascular disease not undergoing cardiac surgery. DESIGN Systematic review and meta-analysis. DATA SOURCES Randomised controlled trials involving a threshold for red blood cell transfusion in hospital. We searched (to 2 November 2015) CENTRAL, Medline, Embase, CINAHL, PubMed, LILACS, NHSBT Transfusion Evidence Library, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, ISRCTN Register, and EU Clinical Trials Register. Authors were contacted for data whenever possible. TRIAL SELECTION Published and unpublished randomised controlled trials comparing a restrictive with liberal transfusion threshold and that included patients with cardiovascular disease. DATA EXTRACTION AND SYNTHESIS Data extraction was completed in duplicate. Risk of bias was assessed using Cochrane methods. Relative risk ratios with 95% confidence intervals were presented in all meta-analyses. Mantel-Haenszel random effects models were used to pool risk ratios. MAIN OUTCOME MEASURES 30 day mortality, and cardiovascular events. RESULTS 41 trials were identified; of these, seven included data on patients with cardiovascular disease. Data from a further four trials enrolling patients with cardiovascular disease were obtained from the authors. In total, 11 trials enrolling patients with cardiovascular disease (n=3033) were included for meta-analysis (restrictive transfusion, n=1514 patients; liberal transfusion, n=1519). The pooled risk ratio for the association between transfusion thresholds and 30 day mortality was 1.15 (95% confidence interval 0.88 to 1.50, P=0.50), with little heterogeneity (I(2)=14%). The risk of acute coronary syndrome in patients managed with restrictive compared with liberal transfusion was increased (nine trials; risk ratio 1.78, 95% confidence interval 1.18 to 2.70, P=0.01, I(2)=0%). CONCLUSIONS The results show that it may not be safe to use a restrictive transfusion threshold of less than 80 g/L in patients with ongoing acute coronary syndrome or chronic cardiovascular disease. Effects on mortality and other outcomes are uncertain. These data support the use of a more liberal transfusion threshold (>80 g/L) for patients with both acute and chronic cardiovascular disease until adequately powered high quality randomised trials have been undertaken in patients with cardiovascular disease. REGISTRATION PROSPERO CRD42014014251.Copyright Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Abstract

BACKGROUND The insertion of central venous catheters (CVCs) may be associated with peri- and post-procedural bleeding. People who require a central line often have disorders of coagulation as a result of their underlying illness, co-morbidities or the effects of treatment. Clinical practice in some institutions is to mitigate the risk of bleeding in these patients by prophylactically transfusing fresh frozen plasma (FFP) in order to correct clotting factor deficiencies prior to central line insertion. However, FFP transfusion is not without risk, and it remains unclear whether this intervention is associated with reduced rates of bleeding or other clinically-meaningful outcomes. OBJECTIVES To assess the effect of different prophylactic plasma transfusion regimens prior to central line insertion in people with abnormal coagulation. SEARCH METHODS We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 3), PubMed (e-publications only), Ovid MEDLINE (from 1946), Ovid Embase (from 1974), the Transfusion Evidence Library (from 1950) and ongoing trial databases to 1 March 2016. SELECTION CRITERIA We included RCTs involving transfusions of plasma to prevent bleeding in people of any age with abnormal coagulation requiring insertion of a central venous catheter, published in English. DATA COLLECTION AND ANALYSIS We used standard methodological procedures expected by Cochrane. MAIN RESULTS We identified four trials eligible for inclusion, of which three are ongoing. We did not exclude any studies because they were not published in English.The included study randomised 81 adults in intensive care whose INR (International Normalised Ratio) was greater than or equal to 1.5 to no FFP or to a single dose of 12 mL/kg FFP prior to undergoing central venous catheterisation (58 participants) or other invasive procedure (23 participants). It is the subgroup of 58 adults undergoing CVC insertion that were included in this review, the study authors provided unpublished data for this review's outcomes.The quality of the evidence was low or very low across different outcomes according to the GRADE methodology. The included study was at high risk of bias due to lack of blinding of participants and personnel and imbalance in the number of participants who had liver disease between study arms.There was insufficient evidence to determine a difference in major procedure-related bleeding within 24 hours (one RCT; 58 participants; no events in either study arm, very low-quality evidence). We are very uncertain whether FFP reduces minor procedure-related bleeding within 24 hours of the study (one RCT; 58 participants, RR 0.67, 95% CI 0.12 to 3.70, very low-quality evidence).No studies were found that looked at: all-cause mortality; the proportion of participants receiving plasma or red cell transfusions; serious adverse reactions (transfusion or line-related complications); number of days in hospital; change in INR; or quality of life.The three ongoing studies are still recruiting participants (expected recruitment: up to 355 participants in total). and are due to be completed by February 2018. AUTHORS' CONCLUSIONS There is only very limited evidence from one RCT to inform the decision whether or not to administer prophylactic plasma prior to central venous catheterisation for people with abnormal coagulation. It is not possible from the current RCT evidence to recommend whether or not prophylactic plasma transfusion is beneficial or harmful in this situation. The three ongoing RCTs will not be able to answer this review's questions, because they are small studies and do not address all of the comparisons included in this review (355 participants in total). To detect an increase in the proportion of participants who had major bleeding from 1 in 100 to 2 in 100 would require a study containing at least 4634 participants (80% power, 5% significance).

Abstract

BACKGROUND Fresh red cells may improve outcomes in critically ill patients by enhancing oxygen delivery while minimizing the risks of toxic effects from cellular changes and the accumulation of bioactive materials in blood components during prolonged storage. METHODS In this multicenter, randomized, blinded trial, we assigned critically ill adults to receive either red cells that had been stored for less than 8 days or standard-issue red cells (the oldest compatible units available in the blood bank). The primary outcome measure was 90-day mortality. RESULTS Between March 2009 and May 2014, at 64 centers in Canada and Europe, 1211 patients were assigned to receive fresh red cells (fresh-blood group) and 1219 patients were assigned to receive standard-issue red cells (standard-blood group). Red cells were stored a mean (+/-SD) of 6.1+/-4.9 days in the fresh-blood group as compared with 22.0+/-8.4 days in the standard-blood group (P<0.001). At 90 days, 448 patients (37.0%) in the fresh-blood group and 430 patients (35.3%) in the standard-blood group had died (absolute risk difference, 1.7 percentage points; 95% confidence interval [CI], -2.1 to 5.5). In the survival analysis, the hazard ratio for death in the fresh-blood group, as compared with the standard-blood group, was 1.1 (95% CI, 0.9 to 1.2; P=0.38). There were no significant between-group differences in any of the secondary outcomes (major illnesses; duration of respiratory, hemodynamic, or renal support; length of stay in the hospital; and transfusion reactions) or in the subgroup analyses. CONCLUSIONS Transfusion of fresh red cells, as compared with standard-issue red cells, did not decrease the 90-day mortality among critically ill adults. (Funded by the Canadian Institutes of Health Research and others; Current Controlled Trials number, ISRCTN44878718.).

Abstract

Acute upper gastrointestinal bleeding (AUGIB) is the commonest reason for hospitalization with hemorrhage in the UK and the leading indication for transfusion of red blood cells (RBCs). Observational studies suggest an association between more liberal RBC transfusion and adverse patient outcomes, and a recent randomised trial reported increased further bleeding and mortality with a liberal transfusion policy. TRIGGER (Transfusion in Gastrointestinal Bleeding) is a pragmatic, cluster randomized trial which aims to evaluate the feasibility and safety of implementing a restrictive versus liberal RBC transfusion policy in adult patients admitted with AUGIB. The trial will take place in 6 UK hospitals, and each centre will be randomly allocated to a transfusion policy. Clinicians throughout each hospital will manage all eligible patients according to the transfusion policy for the 6-month trial recruitment period. In the restrictive centers, patients become eligible for RBC transfusion when their hemoglobin is <8 g/dL. In the liberal centers patients become eligible for transfusion once their hemoglobin is <10 g/dL. All clinicians will have the discretion to transfuse outside of the policy but will be asked to document the reasons for doing so. Feasibility outcome measures include protocol adherence, recruitment rate, and evidence of selection bias. Clinical outcome measures include further bleeding, mortality, thromboembolic events, and infections. Quality of life will be measured using the EuroQol EQ-5D at day 28, and the costs associated with hospitalization for AUGIB in the UK will be estimated. Consent will be sought from participants or their representatives according to patient capacity for use of routine hospital data and day 28 follow up. The study has ethical approval for conduct in England and Scotland. Results will be analysed according to a pre-defined statistical analysis plan and disseminated in peer reviewed publications to relevant stakeholders. The results of this study will inform the feasibility and design of a phase III randomized trial. Copyright 2013 Elsevier Inc. All rights reserved.

Abstract

OBJECTIVES To compare hemoglobin concentration (Hb), RBC use, and patient outcomes when restrictive or liberal blood transfusion strategies are used to treat anemic (Hb <= 90 g/L) critically ill patients of age >= 55 years requiring >= 4 days of mechanical ventilation in ICU. DESIGN Parallel-group randomized multicenter pilot trial. SETTING Six ICUs in the United Kingdom participated between August 2009 and December 2010. PATIENTS One hundred patients (51 restrictive and 49 liberal groups). INTERVENTIONS Patients were randomized to a restrictive (Hb trigger, 70 g/L; target, 71-90 g/L) or liberal (90 g/L; target, 91-110 g/L) transfusion strategy for 14 days or the remainder of ICU stay, whichever was longest. MEASUREMENTS AND MAIN RESULTS Baseline comorbidity rates and illness severity were high, notably for ischemic heart disease (32%). The Hb difference among groups was 13.8 g/L (95% CI, 11.5-16.0 g/L); p < 0.0001); mean Hb during intervention was 81.9 (SD, 5.1) versus 95.7 (6.3) g/L; 21.6% fewer patients in the restrictive group were transfused postrandomization (p < 0.001) and received a median 1 (95% CI, 1-2; p = 0.002) fewer RBC units. Protocol compliance was high. No major differences in organ dysfunction, duration of ventilation, infections, or cardiovascular complications were observed during intensive care and hospital follow-up. Mortality at 180 days postrandomization trended toward higher rates in the liberal group (55%) than in the restrictive group (37%); relative risk was 0.68 (95% CI, 0.44-1.05; p = 0.073). This trend remained in a survival model adjusted for age, gender, ischemic heart disease, Acute Physiology and Chronic Health Evaluation II score, and total non-neurologic Sequential Organ Failure Assessment score at baseline (hazard ratio, 0.54 [95% CI, 0.28-1.03]; p = 0.061). CONCLUSIONS A large trial of transfusion strategies in older mechanically ventilated patients is feasible. This pilot trial found a nonsignificant trend toward lower mortality with restrictive transfusion practice.

Abstract

Review