Abstract

Haemolytic disease of the newborn (HDN) can be associated with significant morbidity. Prompt treatment with intensive phototherapy (PT) and exchange transfusions (ETs) can dramatically improve outcomes. ET is invasive and associated with risks. Intravenous immunoglobulin (IVIG) may be an alternative therapy to prevent use of ET. An international panel of experts was convened to develop evidence-based recommendations regarding the effectiveness and safety of IVIG to reduce the need for ETs, improve neurocognitive outcomes, reduce bilirubin level, reduce the frequency of red blood cell (RBC) transfusions and severity of anaemia, and/or reduce duration of hospitalization for neonates with Rh or ABO-mediated HDN. We used a systematic approach to search and review the literature and then develop recommendations from published data. These recommendations conclude that IVIG should not be routinely used to treat Rh or ABO antibody-mediated HDN. In situations where hyperbilirubinaemia is severe (and ET is imminent), or when ET is not readily available, the role of IVIG is unclear. High-quality studies are urgently needed to assess the optimal use of IVIG in patients with HDN.

Abstract

The efficacy and safety of caplacizumab in individuals with acquired thrombotic thrombocytopenic purpura (aTTP) have been established in the phase 2 TITAN and phase 3 HERCULES trials. Integrated analysis of data from both trials was conducted to increase statistical power for assessing treatment differences in efficacy and safety outcomes. Caplacizumab was associated with a significant reduction in the number of deaths (0 vs 4; P < .05) and a significantly lower incidence of refractory TTP (0 vs 8; P < .05) vs placebo during the treatment period. Consistent with the individual trials, treatment with caplacizumab resulted in a faster time to platelet count response (hazard ratio, 1.65; P < .001), a 72.6% reduction in the proportion of patients with the composite end point of TTP-related death, TTP exacerbation, or occurrence of at least 1 treatment-emergent major thromboembolic event during the treatment period (13.0% vs 47.3%; P < .001), and a 33.3% reduction in the median number of therapeutic plasma exchange days (5.0 vs 7.5 days) vs placebo. No new safety signals were identified; mild mucocutaneous bleeding was the main safety finding. This integrated analysis provided new evidence that caplacizumab prevents mortality and refractory disease in acquired TTP and strengthened individual trial findings, with a confirmed favorable safety and tolerability profile. These trials were registered at www.clinicaltrials.gov as #NCT01151423 and #NCT02553317.

Abstract

BACKGROUND In acquired thrombotic thrombocytopenic purpura (TTP), an immune-mediated deficiency of the von Willebrand factor-cleaving protease ADAMTS13 allows unrestrained adhesion of von Willebrand factor multimers to platelets and microthrombosis, which result in thrombocytopenia, hemolytic anemia, and tissue ischemia. Caplacizumab, an anti-von Willebrand factor humanized, bivalent variable-domain-only immunoglobulin fragment, inhibits interaction between von Willebrand factor multimers and platelets. METHODS In this double-blind, controlled trial, we randomly assigned 145 patients with TTP to receive caplacizumab (10-mg intravenous loading bolus, followed by 10 mg daily subcutaneously) or placebo during plasma exchange and for 30 days thereafter. The primary outcome was the time to normalization of the platelet count, with discontinuation of daily plasma exchange within 5 days thereafter. Key secondary outcomes included a composite of TTP-related death, recurrence of TTP, or a thromboembolic event during the trial treatment period; recurrence of TTP at any time during the trial; refractory TTP; and normalization of organ-damage markers. RESULTS The median time to normalization of the platelet count was shorter with caplacizumab than with placebo (2.69 days [95% confidence interval {CI}, 1.89 to 2.83] vs. 2.88 days [95% CI, 2.68 to 3.56], P=0.01), and patients who received caplacizumab were 1.55 times as likely to have a normalization of the platelet count as those who received placebo. The percentage of patients with a composite outcome event was 74% lower with caplacizumab than with placebo (12% vs. 49%, P<0.001). The percentage of patients who had a recurrence of TTP at any time during the trial was 67% lower with caplacizumab than with placebo (12% vs. 38%, P<0.001). Refractory disease developed in no patients in the caplacizumab group and in three patients in the placebo group. Patients who received caplacizumab needed less plasma exchange and had a shorter hospitalization than those who received placebo. The most common adverse event was mucocutaneous bleeding, which was reported in 65% of the patients in the caplacizumab group and in 48% in the placebo group. During the trial treatment period, three patients in the placebo group died. One patient in the caplacizumab group died from cerebral ischemia after the end of the treatment period. CONCLUSIONS Among patients with TTP, treatment with caplacizumab was associated with faster normalization of the platelet count; a lower incidence of a composite of TTP-related death, recurrence of TTP, or a thromboembolic event during the treatment period; and a lower rate of recurrence of TTP during the trial than placebo. (Funded by Ablynx; HERCULES ClinicalTrials.gov number, NCT02553317 .).

Abstract

Importance: Blood transfusion is one of the most frequently used therapies worldwide and is associated with benefits, risks, and costs. Objective: To develop a set of evidence-based recommendations for patient blood management (PBM) and for research. Evidence Review: The scientific committee developed 17 Population/Intervention/Comparison/Outcome (PICO) questions for red blood cell (RBC) transfusion in adult patients in 3 areas: preoperative anemia (3 questions), RBC transfusion thresholds (11 questions), and implementation of PBM programs (3 questions). These questions guided the literature search in 4 biomedical databases (MEDLINE, EMBASE, Cochrane Library, Transfusion Evidence Library), searched from inception to January 2018. Meta-analyses were conducted with the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) methodology and the Evidence-to-Decision framework by 3 panels including clinical and scientific experts, nurses, patient representatives, and methodologists, to develop clinical recommendations during a consensus conference in Frankfurt/Main, Germany, in April 2018. Findings: From 17607 literature citations associated with the 17 PICO questions, 145 studies, including 63 randomized clinical trials with 23143 patients and 82 observational studies with more than 4 million patients, were analyzed. For preoperative anemia, 4 clinical and 3 research recommendations were developed, including the strong recommendation to detect and manage anemia sufficiently early before major elective surgery. For RBC transfusion thresholds, 4 clinical and 6 research recommendations were developed, including 2 strong clinical recommendations for critically ill but clinically stable intensive care patients with or without septic shock (recommended threshold for RBC transfusion, hemoglobin concentration <7 g/dL) as well as for patients undergoing cardiac surgery (recommended threshold for RBC transfusion, hemoglobin concentration <7.5 g/dL). For implementation of PBM programs, 2 clinical and 3 research recommendations were developed, including recommendations to implement comprehensive PBM programs and to use electronic decision support systems (both conditional recommendations) to improve appropriate RBC utilization. Conclusions and Relevance: The 2018 PBM International Consensus Conference defined the current status of the PBM evidence base for practice and research purposes and established 10 clinical recommendations and 12 research recommendations for preoperative anemia, RBC transfusion thresholds for adults, and implementation of PBM programs. The relative paucity of strong evidence to answer many of the PICO questions supports the need for additional research and an international consensus for accepted definitions and hemoglobin thresholds, as well as clinically meaningful end points for multicenter trials.

Abstract

Importance: Excessive bleeding is a common complication of cardiac surgery. An important cause of bleeding is acquired hypofibrinogenemia (fibrinogen level <1.5-2.0 g/L), for which guidelines recommend fibrinogen replacement with cryoprecipitate or fibrinogen concentrate. The 2 products have important differences, but comparative clinical data are lacking. Objective: To determine if fibrinogen concentrate is noninferior to cryoprecipitate for treatment of bleeding related to hypofibrinogenemia after cardiac surgery. Design, Setting, and Participants: Randomized clinical trial at 11 Canadian hospitals enrolling adult patients experiencing clinically significant bleeding and hypofibrinogenemia after cardiac surgery (from February 10, 2017, to November 1, 2018). Final 28-day follow-up visit was completed on November 28, 2018. Interventions: Fibrinogen concentrate (4 g; n = 415) or cryoprecipitate (10 units; n = 412) for each ordered dose within 24 hours after cardiopulmonary bypass. Main Outcomes and Measures: Primary outcome was blood components (red blood cells, platelets, plasma) administered during 24 hours post bypass. A 2-sample, 1-sided test for the ratio of the mean number of units was conducted to evaluate noninferiority (threshold for noninferiority ratio, <1.2). Results: Of 827 randomized patients, 735 (372 fibrinogen concentrate, 363 cryoprecipitate) were treated and included in the primary analysis (median age, 64 [interquartile range, 53-72] years; 30% women; 72% underwent complex operations; 95% moderate to severe bleeding; and pretreatment fibrinogen level, 1.6 [interquartile range, 1.3-1.9] g/L). The trial met the a priori stopping criterion for noninferiority at the interim analysis after 827 of planned 1200 patients were randomized. Mean 24-hour postbypass allogeneic transfusions were 16.3 (95% CI, 14.9 to 17.8) units in the fibrinogen concentrate group and 17.0 (95% CI, 15.6 to 18.6) units in the cryoprecipitate group (ratio, 0.96 [1-sided 97.5% CI, -infinity to 1.09; P < .001 for noninferiority] [2-sided 95% CI, 0.84 to 1.09; P = .50 for superiority]). Thromboembolic events occurred in 26 patients (7.0%) in the fibrinogen concentrate group and 35 patients (9.6%) in the cryoprecipitate group. Conclusions and Relevance: In patients undergoing cardiac surgery who develop clinically significant bleeding and hypofibrinogenemia after cardiopulmonary bypass, fibrinogen concentrate is noninferior to cryoprecipitate with regard to number of blood components transfused in a 24-hour period post bypass. Use of fibrinogen concentrate may be considered for management of bleeding in patients with acquired hypofibrinogenemia in cardiac surgery. Trial Registration: ClinicalTrials.gov Identifier: NCT03037424.

Abstract

PURPOSE Iron restricted anemia is prevalent in surgical patients and is associated with an increased risk of allogeneic red blood cell (RBC) transfusion and adverse events. Treatment of anemia includes oral and intravenous iron and erythropoiesis stimulating agents (ESAs). More recent studies have focused on the use of intravenous iron as the primary approach to treating anemia. Nevertheless, the optimal treatment strategy for anemia remains to be established. Our primary objective was to evaluate the efficacy and safety of ESA and iron therapy relative to iron therapy alone in reducing RBC transfusion in surgical patients. SOURCE We searched the Cochrane Library, MEDLINE, EMBASE, and ClinicalTrials.gov from inception to May 2018. We included randomized-controlled trials in which adult surgical patients received an ESA and iron, vs iron alone, prior to cardiac and non-cardiac surgery. Our primary outcome was RBC transfusion rate. Secondary outcomes included hemoglobin concentration (post-treatment and postoperatively), number of RBC units transfused, mortality, stroke, myocardial infarction (MI), renal dysfunction, pulmonary embolism (PE), and deep vein thrombosis (DVT). PRINCIPAL FINDINGS In total, 25 studies (4,719 participants) were included. Erythropoiesis stimulating agents and iron therapy reduced RBC transfusion relative to iron therapy (relative risk [RR] 0.57; 95% confidence interval [CI], 0.46 to 0.71) without any change in mortality (RR 1.31; 95% CI, 0.80 to 2.16), stroke (RR 1.91; 95% CI, 0.63 to 5.76), MI (RR 1.12; 95% CI, 0.50 to 2.50), renal dysfunction (RR 0.96; 95% CI, 0.72 to 1.26), PE (RR 0.92; 95% CI, 0.15 to 5.83), or DVT (RR 1.48; 95% CI, 0.95 to 2.31). CONCLUSION Administration of ESA and iron therapy reduced the risk for RBC transfusion compared with iron therapy alone in patients undergoing cardiac and non-cardiac surgery. Nevertheless, publication bias and heterogeneity reduces the confidence of the finding. Although the analysis was probably under-powered for some outcomes, no difference in the incidence of serious adverse events was observed with ESA and iron compared with iron alone. Further large prospective trials are required to confirm these findings.

Abstract

BACKGROUND Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare, life-threatening autoimmune thrombotic microangiopathy. Caplacizumab, an anti-von Willebrand Factor Nanobody((R)) , is effective for treating aTTP episodes and is well tolerated. OBJECTIVES AND METHODS In the phase 3 HERCULES trial (NCT02553317), patients with aTTP received double-blind caplacizumab or placebo during daily therapeutic plasma exchange (TPE) and for ≥30 days thereafter. Patients who experienced an exacerbation while on blinded study drug treatment switched to receive open-label caplacizumab plus re-initiation of daily TPE. Exacerbations were defined as recurrence of disease occurring within 30 days after cessation of daily TPE. RESULTS Thirty-one patients (placebo, n = 28; caplacizumab, n = 3) had an exacerbation during double-blind treatment. Twenty-eight patients switched to open-label caplacizumab (placebo, n = 26; caplacizumab, n = 2); the three others discontinued upon exacerbation. Median time to platelet count response (≥150 x 10(9) /L) was 3.49 days upon receiving caplacizumab. There were no deaths. During open-label treatment, further exacerbation or a major thromboembolic event (vena cava thrombosis) was experienced by one patient (3.6%) each. Consistent with the double-blind phase, the most frequent treatment-emergent adverse events were catheter site hemorrhage (28.6%), headache (21.4%), and epistaxis (17.9%). CONCLUSIONS These results suggest that caplacizumab was efficacious and well tolerated in patients with aTTP who experienced a disease exacerbation during double-blind treatment in HERCULES.

Abstract

Many transfusion guidelines are available, but little appraisal of their quality has been undertaken. The quality of guidelines may potentially influence adoption. Our aim was to determine the quality of evidence-based transfusion guidelines (EBG) for red cells and plasma, using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument, and assess duplication and consistency of recommendations. MEDLINE and EMBASE were systematically searched for EBG from 2005 to June 3, 2016. Citations were reviewed for inclusion in duplicate. A guideline was included if it had a specified clinical question, described a systematic search strategy, included critical appraisal of the literature and a description of how recommendations were developed. Four to six physicians used AGREE II to appraise each guideline. Median and scaled scores were calculated, with each item scored on a scale of one to seven, seven representing the highest score. Of 6174 citations, 30 guidelines met inclusion criteria. Twenty six guidelines had recommendations for red cells and 18 included recommendations for plasma use. The median score, the scaled score and the interquartile range of the scaled score were: scope and purpose: median score 5, scaled score 60%, IQR (49-74%); stakeholder involvement 4, 43%, (33-49%); rigor of development 4, 41%, (19-59%); clarity of presentation 5, 69%, (52-81%); applicability 1, 16%, (9-23%); editorial independence 3, 43%, (20-58%). Sixteen guidelines were evaluated to have a scaled domain score of 50% or less. Variations in recommendations were found for the use of hemoglobin triggers for red cell transfusion in patients with acute coronary syndromes and for plasma use for patients with bleeding. Our findings document, limited rigor in guideline development and duplication and inconsistencies in recommendations for the same topic. The process of developing guidelines for red cells and plasma transfusion can be enhanced to improve implementation.

Abstract

BACKGROUND HLA-matched platelets (PLTs) are widely used to transfuse patients but the effectiveness of HLA matching has not been well defined and the cost is approximately five times the cost of preparing the random-donor PLTs. The objective of this systematic review was to determine whether HLA-matched PLTs lead to a reduction in mortality; reduction in frequency or severity of hemorrhage; reduction in HLA alloimmunization, refractoriness, or PLT utilization; or improvement in PLT count increment in patients with hypoproliferative thrombocytopenia. STUDY DESIGN AND METHODS We conducted a literature search of MEDLINE, Cochrane Controlled Register of Clinical Trials, EMBASE, and PubMed databases to April 2012. RESULTS A total of 788 citations were reviewed and 30 reports were included in the analysis. Most studies did not include technologies currently in use for HLA typing or detection of HLA antibodies as 75% were conducted before the year 2000. None of the studies were adequately powered to detect an effect on mortality or hemorrhage. HLA-matched PLTs did not reduce alloimmunization and refractoriness rates beyond that offered by leukoreduction, and utilization was not consistently improved. HLA-matched PLTs led to better 1-hour posttransfusion count increments and percentage of PLT recovery in refractory patients; however, the effect at 24 hours was inconsistent. CONCLUSION The correlation of the PLT increment with other clinical outcomes and the effect of leukoreduction on HLA-matched PLT transfusion could not be determined. Prospective studies utilizing current technology and examining clinical outcomes are necessary to demonstrate the effectiveness of HLA-matched PLT transfusion. 2013 American Association of Blood Banks.