How low should we go: A systematic review and meta-analysis of the impact of restrictive red blood cell transfusion strategies in oncology

Restrictive versus liberal red blood cell transfusion strategies for people with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without haematopoietic stem cell support

BACKGROUND

An estimated one-quarter to one-half of people diagnosed with haematological malignancies experience anaemia. There are different strategies for red blood cell (RBC) transfusions to treat anaemia. A restrictive transfusion strategy permits a lower haemoglobin (Hb) level whereas a liberal transfusion strategy aims to maintain a higher Hb. The most effective and safest strategy is unknown.

OBJECTIVES

To determine the efficacy and safety of restrictive versus liberal RBC transfusion strategies for people diagnosed with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without a haematopoietic stem cell transplant (HSCT).

SEARCH METHODS

We searched for randomised controlled trials (RCTs) and non-randomised studies (NRS) in MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1982), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2023, Issue 2), and eight other databases (including three trial registries) to 21 March 2023. We also searched grey literature and contacted experts in transfusion for additional trials. There were no language, date or publication status restrictions.

SELECTION CRITERIA

We included RCTs and prospective NRS that evaluated restrictive versus liberal RBC transfusion strategies in children or adults with malignant haematological disorders receiving intensive chemotherapy or radiotherapy, or both, with or without HSCT.

DATA COLLECTION AND ANALYSIS

Two authors independently screened references, full-text reports of potentially relevant studies, extracted data from the studies, and assessed the risk of bias. Any disagreement was discussed and resolved with a third review author. Dichotomous outcomes were presented as a risk ratio (RR) with a 95% confidence interval (CI). Narrative syntheses were used for heterogeneous outcome measures. Review Manager Web was used to meta-analyse the data. Main outcomes of interest included: all-cause mortality at 31 to 100 days, quality of life, number of participants with any bleeding, number of participants with clinically significant bleeding, serious infections, length of hospital admission (days) and hospital readmission at 0 to 3 months. The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

Nine studies met eligibility; eight RCTs and one NRS. Six hundred and forty-four participants were included from six completed RCTs (n = 560) and one completed NRS (n = 84), with two ongoing RCTs consisting of 294 participants (260 adult and 34 paediatric) pending inclusion. Only one completed RCT included children receiving HSCT (n = 6); the other five RCTs only included adults: 239 with acute leukaemia receiving chemotherapy and 315 receiving HSCT (166 allogeneic and 149 autologous). The transfusion threshold ranged from 70 g/L to 80 g/L for restrictive and from 80 g/L to 120 g/L for liberal strategies. Effects were reported in the summary of findings tables only for the trials that included adults to reduce indirectness due to the limited evidence contributed by the prematurely terminated paediatric trial. Evidence from RCTs Overall, there may be little to no difference in the number of participants who die within 31 to 100 days using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 451 participants; RR 1.00, 95% CI 0.27 to 3.70, P=0.99; very low-certainty evidence). There may be little to no difference in quality of life at 0 to 3 months using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 431 participants; analysis unable to be completed due to heterogeneity; very low-certainty evidence). There may be little to no difference in the number of participants who suffer from any bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies; 448 participants; RR 0.91, 95% CI 0.78 to 1.06, P = 0.22; low-certainty evidence). There may be little to no difference in the number of participants who suffer from clinically significant bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (four studies; 511 participants; RR: 0.94, 95% CI 0.74 to 1.19, P = 0.60; low-certainty evidence). There may be little to no difference in the number of participants who experience serious infections at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies, 451 participants; RR: 1.20, 95% CI 0.93 to 1.55, P = 0.17; low-certainty evidence). A restrictive transfusion strategy likely results in little to no difference in the length of hospital admission at 0 to 3 months compared to a liberal strategy (two studies; 388 participants; analysis unable to be completed due to heterogeneity in reporting; moderate-certainty evidence). There may be little to no difference between hospital readmission using a restrictive transfusion strategy compared to a liberal transfusion strategy (one study, 299 participants; RR: 0.89, 95% CI 0.52 to 1.50; P = 0.65; low-certainty evidence). Evidence from NRS The evidence is very uncertain whether a restrictive RBC transfusion strategy: reduces the risk of death within 100 days (one study, 84 participants, restrictive 1 death; liberal 1 death; very low-certainty evidence); or decreases the risk of clinically significant bleeding (one study, 84 participants, restrictive 3; liberal 8; very low-certainty evidence). No NRS reported on the other eligible outcomes.

AUTHORS' CONCLUSIONS

Findings from this review were based on seven studies and 644 participants. Definite conclusions are challenging given the relatively few included studies, low number of included participants, heterogeneity of intervention and outcome reporting, and overall certainty of evidence. To increase the certainty of the true effect of a restrictive RBC transfusion strategy on clinical outcomes, there is a need for rigorously designed and executed studies. The evidence is largely based on two populations: adults with acute leukaemia receiving intensive chemotherapy and adults with haematologic malignancy requiring HSCT. Despite the addition of 405 participants from three RCTs to the previous review's results, there is still insufficient evidence to answer this review's primary outcome. If we assume a mortality rate of 3% within 100 days, we would need a total of 1492 participants to have an 80% chance of detecting, at a 5% level of significance, an increase in all-cause mortality from 3% to 6%. Further RCTs are needed overall, particularly in children.

Anemia in patients receiving anticancer treatments: focus on novel therapeutic approaches

Anemia is common in cancer patients and impacts on quality of life and prognosis. It is typically multifactorial, often involving different pathophysiological mechanisms, making treatment a difficult task. In patients undergoing active anticancer treatments like chemotherapy, decreased red blood cell (RBC) production due to myelosuppression generally predominates, but absolute or functional iron deficiency frequently coexists. Current treatments for chemotherapy-related anemia include blood transfusions, erythropoiesis-stimulating agents, and iron supplementation. Each option has limitations, and there is an urgent need for novel approaches. After decades of relative immobilism, several promising anti-anemic drugs are now entering the clinical scenario. Emerging novel classes of anti-anemic drugs recently introduced or in development for other types of anemia include activin receptor ligand traps, hypoxia-inducible factor-prolyl hydroxylase inhibitors, and hepcidin antagonists. Here, we discuss their possible role in the treatment of anemia observed in patients receiving anticancer therapies.

Explaining the Elusive Nature of a Well-Defined Threshold for Blood Transfusion in Advanced Epithelial Ovarian Cancer Cytoreductive Surgery

There is no well-defined threshold for intra-operative blood transfusion (BT) in advanced epithelial ovarian cancer (EOC) surgery. To address this, we devised a Machine Learning (ML)-driven prediction algorithm aimed at prompting and elucidating a communication alert for BT based on anticipated peri-operative events independent of existing BT policies. We analyzed data from 403 EOC patients who underwent cytoreductive surgery between 2014 and 2019. The estimated blood volume (EBV), calculated using the formula EBV = weight × 80, served for setting a 10% EBV threshold for individual intervention. Based on known estimated blood loss (EBL), we identified two distinct groups. The Receiver operating characteristic (ROC) curves revealed satisfactory results for predicting events above the established threshold (AUC 0.823, 95% CI 0.76-0.88). Operative time (OT) was the most significant factor influencing predictions. Intra-operative blood loss exceeding 10% EBV was associated with OT > 250 min, primary surgery, serous histology, performance status 0, R2 resection and surgical complexity score > 4. Certain sub-procedures including large bowel resection, stoma formation, ileocecal resection/right hemicolectomy, mesenteric resection, bladder and upper abdominal peritonectomy demonstrated clear associations with an elevated interventional risk. Our findings emphasize the importance of obtaining a rough estimate of OT in advance for precise prediction of blood requirements.

Adverse postoperative outcomes associated with perioperative blood transfusion in gynecologic oncology surgery

OBJECTIVE

To examine the incidence of perioperative blood transfusion and association with 30 day postoperative outcomes in gynecologic cancer surgery.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify all gynecologic oncology cases from 2013 to 2019. Clinical and surgical characteristics and 30 day postoperative complications were retrieved. The primary outcome was 30 day composite morbidity, based on the occurrence of one or more of the 18 adverse events. Secondary outcomes were 30 day mortality, length of stay in hospital, and composite surgical site infection, defined as superficial, deep, or organ space surgical site infection. The χ² test and logistic regression analyses were performed to compare the outcomes of patients with and without perioperative blood transfusion.

RESULTS

There were 62 531 surgical gynecologic oncology cases with an overall transfusion incidence of 9.4%. The transfusion incidence was significantly higher at 22.4% with laparotomy compared with 1.7% with minimally invasive surgery (p<0.0001). On multivariable analysis for laparotomy patients, blood transfusion was predictive of composite morbidity (adjusted odds ratio (OR) 1.65, 95% confidence interval (CI) 1.48 to 1.85) and length of stay in hospital ≥5 days (adjusted OR 9.02, 95% CI 8.21 to 9.92). In advanced ovarian cancer patients (n=3890), the incidence of perioperative blood transfusion was 40.8%. On multivariable analysis, perioperative blood transfusion was the most predictive factor for composite morbidity (adjusted OR 1.67, 95% CI 1.35 to 2.07) and length of stay in hospital ≥7 days (adjusted OR 9.75, 95% CI 7.79 to 12.21).

CONCLUSION

Perioperative blood transfusion is associated with increased composite morbidity and prolonged length of stay in hospital. Preoperative patient optimization and institutional practices should be reviewed to improve the use of blood bank resources and adherence to restrictive blood transfusion protocols.

Anemia and iron deficiency in cancer patients: the role of intravenous iron supplements (a literature review)

Anemia in patients with malignancies is a common disorder that has a markedly negative impact on quality of life and overall prognosis. The pathogenesis of anemia is complex and multifactorial, depending on the type and stage of malignancy, nutritional status, renal function, age and gender, cytostatic drug, dose, and chemotherapeutic regimen, with iron deficiency often being the main and potentially treatable factor for anemia. In cancer patients, it can be caused by various concomitant mechanisms, including bleeding (e.g., in malignant gastrointestinal tumors or after surgery), malnutrition, medication, and hepcidin-induced iron sequestration in macrophages, with subsequent iron-deficient erythropoiesis. The variety of clinical manifestations of anemia makes it challenging to establish universal criteria to develop optimal treatments. Current therapy for anemia in malignant tumors includes replacement therapy with an iron supplement, erythropoiesis-stimulating agents (erythropoietins), and blood transfusions. However, blood transfusions should be minimized due to the high risks and costs. Therapy with an iron supplement is an effective approach to correcting the iron deficiency. It can increase the efficacy of erythropoiesis-stimulating drugs and reduce the need for blood transfusions. Published guidelines suggest the wide use of intravenous iron supplements. This article discusses possible approaches to treating iron deficiency in cancer patients in various clinical settings. We build on current guidelines and emphasize the need for further research in this area.

Transfusion use and effect on progression-free, overall survival, and quality of life in upfront treatment of advanced epithelial ovarian cancer: evaluation of the European Organization for Research and Treatment EORTC-55971 Cohort

BACKGROUND

The impact of blood transfusion on ovarian cancer survival is uncertain.

OBJECTIVE

To investigate whether peri-operative blood transfusion negatively impacted progression-free survival, overall survival, and quality of life in patients with advanced ovarian cancer.

METHODS

We performed an ancillary analysis of the European Organization for Research and Treatment (EORTC) 55971 phase III trial, in which patients were randomized to primary debulking surgery versus neoadjuvant chemotherapy. Patients included in the per-protocol analysis were categorized by receipt of a transfusion.

RESULTS

612 of 632 (97%) of patients had adequate data for analysis. Of those, 323 (53%) received a transfusion. The transfusion cohort was more likely to have had better Word Health Organization (WHO) performance status, serous histology, undergone primary debulking surgery, and received more aggressive surgery, with higher rates of no gross residual disease. Median overall survival was 34.0 vs 35.2 months in the no transfusion and transfusion cohorts (p=0.97). The adjusted HR for death was 1.18 (95% CI 0.94 to 1.48) in favor of the transfusion cohort. Median progression-free survival was 13.6 vs 12.6 months in the no transfusion and transfusion cohorts (p=0.96). The adjusted HR for progression was 1.14 (95% CI 0.91 to 1.43). There were no significant differences in global quality of life, fatigue, dyspnea, or physical functioning between the two cohorts at baseline or at any of the four assessment times. Grade 3 and 4 surgical site infections were more common in the transfusion cohort.

CONCLUSION

Transfusion did not negatively impact progression-free survival or overall survival; however, it was associated with increased peri-operative morbidity without improvements in quality of life.

Incidence of anemia and red blood cell (RBC) transfusion requirement in breast cancer

Background

Cancer-related anaemia is one of the main burdens in oncology, although the available data on its prevalence and treatment options such as blood transfusion are often contradictory. This study aimed to evaluate the prevalence of anaemia and the requirement for packed red blood cell (PRBC) transfusion among women with breast cancer (BC) and to determine the associated factors for chemotherapy-induced anaemia (CIA).

Methods

This cross-sectional retrospective study conducted in Kelantan involved 104 newly diagnosed female BC patients from 2015 to 2016 who underwent chemotherapy. For statistical analysis, chi-square was used to compare between CIA and non-CIA groups. In addition, simple and multiple logistic regression were used to determine the association of the CIA.

Results

Our study revealed that 34.6% (n=36) of patients had mild anaemia, and 59.6% (n=62) had normal haemoglobin at pre-chemotherapy. The prevalence of anaemia increased from 40.4% to 77% at the end of our study. About 30.8% of patients received PRBC transfusion during chemotherapy with mean haemoglobin before the first transfusion of 7.9 g/dl. CIA was observed in 54.8% of cases. There was no significant association between CIA concerning the patient characteristic, cancer characteristic, or cancer treatment.

Conclusion

We concluded that a significant proportion (40.4%) of BC patients was anaemic even before chemotherapy, with the red blood cell requirements up to 30.8% throughout chemotherapy. A larger prospective study is needed to determine the predictors for the CIA and subsequently improve patient management.

[Rational therapy with erythrocyte concentrates - Update 2022]

The use of red blood cell concentrates must follow the dictates of a rational indication. To further ensure this, the "Cross-Sectional Guidelines for Therapy with Blood Components and Plasma Derivatives" 1 of the German Medical Association, published in 2009 and last revised in part in 2014, were systematically revised in 2020. This article presents them.

Transfusion‑related immunomodulation in patients with cancer: Focus on the impact of extracellular vesicles from stored red blood cells (Review)

Red blood cell (RBC) transfusions may have a negative impact on the prognosis of patients with cancer, where transfusion‑related immunomodulation (TRIM) may be a significant contributing factor. A number of components have been indicated to be associated with TRIM. Among these, the impact of extracellular vesicles (EVs) has been garnering increasing attention from researchers. EVs are defined as nano‑scale, cell‑derived vesicles that carry a variety of bioactive molecules, including proteins, nucleic acids and lipids, to mediate cell‑to‑cell communication and exert immunoregulatory functions. RBCs in storage constitutively secrete EVs, which serve an important role in TRIM in patients with cancer receiving a blood transfusion. Therefore, the present review aimed to first summarize the available information on the biogenesis and characterization of EVs. Subsequently, the possible mechanisms of TRIM in patients with cancer and the impact of EVs on TRIM were discussed, aiming to provide an outlook for future studies, specifically for formulating recommendations for managing patients with cancer receiving RBC transfusions.

Physiology and Inflammation Driven Pathophysiology of Iron Homeostasis-Mechanistic Insights into Anemia of Inflammation and Its Treatment

Anemia is very common in patients with inflammatory disorders. Its prevalence is associated with severity of the underlying disease, and it negatively affects quality of life and cardio-vascular performance of patients. Anemia of inflammation (AI) is caused by disturbances of iron metabolism resulting in iron retention within macrophages, a reduced erythrocyte half-life, and cytokine mediated inhibition of erythropoietin function and erythroid progenitor cell differentiation. AI is mostly mild to moderate, normochromic and normocytic, and characterized by low circulating iron, but normal and increased levels of the storage protein ferritin and the iron hormone hepcidin. The primary therapeutic approach for AI is treatment of the underlying inflammatory disease which mostly results in normalization of hemoglobin levels over time unless other pathologies such as vitamin deficiencies, true iron deficiency on the basis of bleeding episodes, or renal insufficiency are present. If the underlying disease and/or anemia are not resolved, iron supplementation therapy and/or treatment with erythropoietin stimulating agents may be considered whereas blood transfusions are an emergency treatment for life-threatening anemia. New treatments with hepcidin-modifying strategies and stabilizers of hypoxia inducible factors emerge but their therapeutic efficacy for treatment of AI in ill patients needs to be evaluated in clinical trials.

How I treat anemia in the perisurgical setting

Anemia is a common finding in the perioperative setting with significant untoward consequences including worsening of outcomes and diminished quality of life as well as increased risk of allogeneic blood transfusions. Here, we present 3 cases that illustrate how anemia can be perioperatively managed in patients undergoing cardiac, orthopedic, and oncology surgeries. Timely detection of anemia prior to high-blood loss surgeries can allow clinicians to manage it and optimize hemoglobin level, making patients better prepared for the surgery. Treatment of anemia should be guided by the etiology and may include erythropoietic agents, folic acid, B12, and iron preparations. Other blood management strategies geared toward reducing surgical blood loss such as autologous transfusion techniques and agents to optimize hemostasis are used during surgery and in the immediate postoperative period. Patients should be closely monitored following surgery for signs of ongoing bleeding in need of control. Finally, screening for and management of anemia should continue in the postoperative and postdischarge period, as persistence and recurrence of anemia can further undermine patient's outcomes.

Rationale Therapie mit Erythrozytenkonzentraten – Update 2020

Der Einsatz von Erythrozytenkonzentraten muss dem Gebot einer rationalen Indikation folgen. Um dies weiter zu gewährleisten, wurden die 2009 publizierten und zuletzt 2014 in Teilen revidierten „Querschnitts-Leitlinien zur Therapie mit Blutkomponenten und Plasmaderivaten“ 1 der Bundesärztekammer 2020 einer systematischen Novellierung unterzogen. Der Artikel stellt sie vor.

Maintaining adequate donations and a sustainable blood supply: Lessons learned

Background

The availability of a safe blood supply is a key component of transfusion medicine. A decade of decreased blood use, decreased payment for products, and a dwindling donor base have placed the sustainability of the US blood supply at risk.

Study Design and Methods

A literature review was performed for blood center (BC) and hospital disaster management, chronically transfusion‐dependent diseases, and appropriate use of group O‐negative red blood cells (RBCs), and the Choosing Wisely campaign. The aim was to identify current practice and to make recommendations for BC and hospital actions.

Results

While BCs are better prepared to handle disasters than after the 9/11 attacks, messaging to the public remains difficult, as donors often do not realize that blood transfused during a disaster was likely collected before the event. BCs and transfusion services should participate in drafting disaster response plans. Hospitals should maintain inventories adequate for patients in the event supply is disrupted. Providing specialty products for transfusion‐dependent patients can strain collections, lead to increased use of group O RBCs, and create logistical inventory challenges for hospitals. The AABB Choosing Wisely initiative addresses overuse of blood components to optimally use this precious resource. Group O‐negative RBCs should be transfused only to patients who truly need them.

Conclusions

Collecting and maintaining a blood supply robust enough to handle disasters and transfusion‐dependent patients in need of specialty products is challenging. Collaboration of all parties should help to optimize resources, ensure appropriate collections, improve patient care, and ultimately result in a robust, sustainable blood supply.

Safety Maintains Lean Sustainability and Increases Performance through Fault Control

Almost every industrial and service enterprise adopts some form of Environmental Health and Safety (HSE) practices. However, there is no unified measurement implementation framework to resist losses exacerbated due to the “lack of safety precautions”, which must be considered one of the most dangerous Lean wastes because it jeopardizes the investment in the Hex-Bottom-Line (HBLs). Despite the widespread nature of the Lean approach, there no unified and collected framework to track and measure the effectiveness of the safety measures’ progress. Therefore, the enterprises resort to establishing their own tailored safety framework that maintains their competitiveness and sustainability. The enterprises must provide insight into safety deficiencies (i.e., faults and losses suffered) that have been measured via downtime spans and costs (Lean waste), reflecting the poor Lean Safety Performance Level (LSPL). This paper aims to shed light on two issues: (1) the adverse impact of the “lack of safety precautions” on LSPL caused by the absence of (2) a Lean Safety framework included in the Measurement and Analysis phases of Define Measure Analyze Identify Control (DMAIC). This framework is based on forecasting losses and faults according to their consumption time. The proposed framework appreciates the losses’ severity (time consumption and costs) via Fault Mode and Effect Forecasting (FMEF) aided by Artificial Neural Networks through sequential steps known as Safety Function Deployment (SFD).

Correlation between hematological parameters and outcome in patients with locally advanced cervical cancer treated by concomitant chemoradiotherapy

Background

Hemoglobin (Hb), white blood cell (WBC), and polymorphonuclear neutrophil (PMN) blood counts may be correlated with outcomes in patients with locally advanced cervical cancer.

Methods

Hb, WBC, and PMN counts were measured at diagnosis and during concomitant cisplatin‐based chemoradiotherapy (CCRT) in a retrospective sample of 103 patients between 2010 and 2017. Red blood cell (RBC) transfusions were also recorded. The associations between hematological variables and patient overall survival (OS) and recurrence‐free survival (RFS) were assessed by Cox regression models.

Results

The 3‐year OS and RFS rates were 81.4% and 76.8%, respectively. In addition to tumor size and smoking, OS and RFS were found to be significantly associated with changes in WBC and PMN counts from the first to the last cisplatin cycle. Hb count throughout the treatment and RBC transfusions were not predictive of outcome.

Conclusions

This study found no association between Hb count or RBC transfusions and outcome. The daily practice of maintaining the Hb count above 12 g/dL during CCRT should be weighed against the potential risks of transfusions. Drops in WBC and PMN counts during treatment positively impacted OS and RFS and could, therefore, serve as biomarkers during CCRT to adapt the follow‐up and consider the need for adjuvant systemic treatments.

Systematic reviews and meta-analyses comparing mortality in restrictive and liberal haemoglobin thresholds for red cell transfusion: an overview of systematic reviews

BACKGROUND

There are no overviews of systematic reviews investigating haemoglobin thresholds for transfusion. This is important as the literature on transfusion thresholds has grown considerably in recent years. Our aim was to synthesise evidence from systematic reviews and meta-analyses of the effects of restrictive and liberal transfusion strategies on mortality.

METHODS

This was a systematic review of systematic reviews (overview). We searched MEDLINE, Embase, Web of Science Core Collection, PubMed, Google Scholar, and the Joanna Briggs Institute EBP Database, from 2008 to 2018. We included systematic reviews and meta-analyses of randomised controlled trials comparing mortality in patients assigned to red cell transfusion strategies based on haemoglobin thresholds. Two independent reviewers extracted data and assessed methodological quality. We assessed the methodological quality of included reviews using AMSTAR 2 and the quality of evidence pooled using an algorithm to assign GRADE levels.

RESULTS

We included 19 systematic reviews reporting 33 meta-analyses of mortality outcomes from 53 unique randomised controlled trials. Of the 33 meta-analyses, one was graded as high quality, 15 were moderate, and 17 were low. Of the meta-analyses presenting high- to moderate-quality evidence, 12 (75.0%) reported no statistically significant difference in mortality between restrictive and liberal transfusion groups and four (25.0%) reported significantly lower mortality for patients assigned to a restrictive transfusion strategy. We found few systematic reviews addressed clinical differences between included studies: variation was observed in haemoglobin threshold concentrations, the absolute between group difference in haemoglobin threshold concentration, time to randomisation (resulting in transfusions administered prior to randomisation), and transfusion dosing regimens.

CONCLUSIONS

Meta-analyses graded as high to moderate quality indicate that in most patient populations no difference in mortality exists between patients assigned to a restrictive or liberal transfusion strategy.

TRIAL REGISTRATION

PROSPERO CRD42019120503.

Liberal Transfusion versus Restrictive Transfusion and Outcomes in Critically Ill Adults: A Meta-Analysis

Objective

We aimed to determine whether the restrictive red-cell transfusion strategy was superior to the liberal one in reducing all-cause mortality in critically ill adults.

Methods

The MEDLINE, EMBASE, PubMed, Web of Science, and Cochrane Library Central Register of Controlled Trials databases were searched from inception to January 2019 to identify meta-analyses or systematic reviews and published randomized controlled trials which were restrictive versus liberal blood transfusion with mortality as the endpoint in critically ill adults. We used two search routes whereby one search was restricted to systematic reviews, reviews, or meta-analysis, and the other was not restricted. There were no date restrictions, but language was limited to English and the population was restricted to critically ill adults. The data of study methods, participant characteristics, and outcomes were extracted and analyzed independently by 2 reviewers. The main outcome was all-cause mortality.

Results

Through screening the obtained records, we enrolled 7 randomized clinical trials that included information on restrictive versus liberal red-cell transfusion and mortality of intensive care unit (ICU) patients. Involving a total of 7,363 ICU adult patients, ICU mortality (risk ratio [RR] 0.82, 95% confidence interval [CI] 0.62, 1.08, p = 0.15), 28/30-day mortality (RR 0.98, 95% CI 0.84, 1.13, p = 0.74), 60-day mortality (RR 1.01, 95% CI 0.87, 1.16, p = 0.91), 90-day mortality (RR 1.02, 95% CI 0.92, 1.14, p = 0.69), 120-day mortality (RR 1.29, 95% CI 0.67, 2.47, p = 0.44), and 180-day mortality (RR 0.91, 95% CI 0.75, 1.12, p = 0.38) were not statistically significantly different when the restrictive transfusion strategy was compared with the liberal transfusion strategy. However, we surprisingly discovered that 112 out of 469 (24%) patients who received a unit RBC transfusion when hemoglobin was less than 7 g/dL, and 142 out of 469 (30.3%) who received a unit of RBC transfused with hemoglobin less than 9 g/dL, had died during hospitalization (RR 0.79, 95% CI 0.64, 0.97, p = 0.03). The results showed that the restrictive transfusion strategy could decrease in-hospital mortality compared with the liberal transfusion strategy. It was safe to utilize a restrictive transfusion threshold of less than 7 g/dL in stable critically ill adults.

Conclusions

In this study, we found that the restrictive red-cell transfusion strategy potentially reduced in-hospital mortality in critically ill adults with anemia compared with the liberal strategy.

Application of Perioperative Transfusion Trigger Score in Patients Undergoing Surgical Treatment of Malignant Tumor

The present study aimed to investigate the clinical effects of the brand new perioperative transfusion trigger score (POTTS) system in patients undergoing malignant tumor surgeries. 442 cases of patients diagnosed with malignant tumor were randomly selected (from January 2012 to December 2016) from Zunyi Medical University and were divided into 3 experimental groups. Patients in the POTTS group were transfused by the POTTS guideline perioperatively, while patients in the 7-10 g group were treated by the traditional transfusion guidelines existed (restrictive transfusion strategy), patients in the 10 g group should be transfused to keep the Hb level no less than 10 g/dL (liberal transfusion strategy). Baseline information, operation time, bleeding volume, transfusion amount, incision healing time, postoperative complications, metastasis and recurrence were observed and recorded. Postoperative short-term mortality was comparable of the 3 groups, 3 cases of death all occurred in 10 g group, there was no significant difference in the incidence of postoperative complications, including infectious complications and coagulation related complications. Follow-up to date, there were 25 cases, 29 cases and 29 cases of tumor recurrence and metastasis in the three groups, but no statistical difference observed. The present findings show that the POTTS transfusion system is more advantageous with regard to save blood and relieve economic burdens of patients, and does not affect the long-term recurrence and metastasis rate of malignant tumor.

Recent update in the pathogenesis and treatment of chemotherapy and cancer induced anemia

Cancer and chemotherapy-induced anemia (CIA) is commonly encountered among patients undergoing active chemotherapy with or without radiation therapy. Its pathogenesis is complex and is often difficult to identify. Symptoms related to CIA may have a negative impact on quality of life and may influence treatment efficacy, disease progression and even survival. The recent major setback of erythropoietin-stimulating agents (ESAs) and the reluctance to transfuse cancer patients with mild and even moderate anemia, had resulted in significant under-treatment of CIA. The discovery of hepcidin and its role in iron homeostasis has revolutionized our understanding of the pathogenesis of iron deficiency and iron overload states. In the present review we examine the multifactorial pathogenesis of CIA, addressing the main mechanisms by which the tumor and immune system affect anemia. Additionally, we discuss the treatment options with more focus on the utilization of the new intravenous iron formulations for this indication.

Lifetime Transfusion Burden and Transfusion-Related Iron Overload in Adult Survivors of Solid Malignancies

BACKGROUND

Limited data exist on transfusion burden and transfusion-related iron overload in adult survivors of solid malignancies.

METHODS

Hospital-specific cancer registry data of patients with solid tumor receiving systemic anticancer treatment between January 2008 and September 2009 at the Oncology Department of the Leiden University Medical Center (The Netherlands) were retrieved and cross-referenced with red blood cell (RBC) transfusion records. Individual lifetime transfusion burden was captured in April 2015. Multitransfused long-term survivors with serum ferritin >500 μg/L were subsequently screened for hepatic and cardiac iron overload using 1.5 Tesla magnetic resonance imaging.

RESULTS

The study population consisted of 775 adult patients with solid cancer (45.2% male; median age, 58 years; >75% chemotherapy-treated), 423 (54.6%) of whom were transfused with a median of 6.0 RBC units (range 1-67). Transfusion triggers were symptomatic anemia or hemoglobin <8.1-8.9 g/dL prior to each myelosuppressive chemotherapy cycle. We identified 123 (15.9%) patients across all tumor types with a lifetime transfusion burden of ≥10 RBC units. In the absence of a hemovigilance program, none of these multitransfused patients was screened for iron overload despite a median survival of 4.6 years. In 2015 at disclosure of transfusion burden, 26 multitransfused patients were alive. Six (23.1%) had hepatic iron overload: 3.9-11.2 mg Fe/g dry weight. No cardiac iron depositions were found.

CONCLUSION

Patients with solid malignancies are at risk for multitransfusion and iron overload even when adhering to restrictive RBC transfusion policies. With improved long-term cancer survivorship, increased awareness of iatrogenic side effects of supportive therapy and development of evidence-based guidelines are essential.

IMPLICATIONS FOR PRACTICE

In the presence of a restrictive transfusion policy, ∼30% of transfused adult patients with solid cancer are multitransfused and ∼50% become long-term survivors, underscoring the need for evidence-based guidelines for the detection and management of transfusion-related iron overload in this group of patients. In each institution, a hemovigilance program should be implemented that captures the lifetime cumulative transfusion burden in all patients with cancer, irrespective of tumor type. This instrument will allow timely assessment and treatment of iron overload in cancer survivors, thus preventing organ dysfunction and decreased quality of life.

Choosing Wisely: Decreasing the incidence of perioperative blood transfusions in gynecologic oncology

OBJECTIVE

To evaluate the efficacy and economic impact of a transfusion reduction initiative for patients undergoing gynecologic surgery.

METHODS

We conducted a prospective healthcare improvement study to align transfusion practices with the American Society of Hematology's Choosing Wisely® campaign. Baseline transfusion rates were determined retrospectively for all major gynecologic surgical cases from 3/1/14 to 6/30/14. Data for the post-intervention period from 5/15/15 to 5/16/16 were captured prospectively. The primary outcome was transfusion within 72 h of surgery. Secondary outcomes included perioperative morbidity, mortality, number of units ordered per transfusion episode and cost.

RESULTS

We identified 1281 surgical cases, 334 in the baseline and 947 in the post-implementation cohort. The baseline cohort was noted to have a higher median estimated blood loss (100 v. 75 mL, P < 0.01). Otherwise, there were no differences in clinical or perioperative characteristics between the two cohorts. The perioperative transfusion rate decreased from 24% to 11% (adjusted OR 0.27, 95% CI 0.16 to 0.45; P < 0.001). The perioperative laparotomy transfusion rate decreased from 48% to 23% (adjusted OR 0.21, 95% CI 0.12, 0.37; P < 0.001). The number of occurrences in which more than one unit of blood was ordered at a time decreased from 65% to 23%, P < 0.001. The incidence of surgical site infections declined in the post-intervention group, otherwise there were no differences in 30-day mortality, cardiac, venous thromboembolism or readmission rates between the groups. The projected cost savings was $161,112 over the 12-month intervention period.

CONCLUSIONS

Implementation of an educational based transfusion reduction program was associated with substantial reductions in perioperative transfusions and cost without significant changes in morbidity or mortality.

A preoperative risk score to predict red blood cell transfusion in patients undergoing hysterectomy for ovarian cancer

BACKGROUND

Patients with ovarian cancer experience a high rate of anemia throughout their treatment course, with rates that range from 19-95%. Blood transfusions offer symptom relief but may be costly, are limited in supply, and have been associated with worse 30-day surgical morbidity and mortality rates.

OBJECTIVE

The purpose of this study was to identify risk factors for blood transfusion with packed red blood cell and to develop a transfusion risk score to identify patients who undergo surgery for ovarian cancer and who are at lowest risk for a blood transfusion. Our aim was to help clinicians identify those patients who may not require a crossmatch to encourage resource use and cost-savings.

STUDY DESIGN

This is a retrospective database cohort study of 3470 patients who underwent hysterectomy for ovarian cancer with the use the National Surgical Quality Improvement Program database from 2014-2016. The association between risk factors with respect to 30-day postoperative blood transfusion was modeled with the use of logistic regression. A risk score to predict blood transfusion was created.

RESULTS

Eight hundred ninety-one (25.7%) patients received a blood transfusion. In multivariate analysis, blood transfusion was associated independently with age (odds ratio, 1.90, P<.01), African American race (odds ratio, 2.30; P<.01), ascites (odds ratio, 1.89; P=.02), preoperative hematocrit level <30% (odds ratio, 10.70; P<.01), preoperative platelet count >400×10⁹/L (odds ratio, 1.75; P<.01), occurrence of disseminated cancer (odds ratio, 1.71; P<.01), open surgical approach (odds ratio, 7.88; P<.01), operative time >3 hours (odds ratio, 2.19; P<.01), and additional surgical procedures that included large bowel resection (odds ratio, 4.23; P<.01), bladder/ureter resection (odds ratio, 1.69; P=.02), and pelvic exenteration (P=.02). A preoperative risk score that used age, race, ascites, preoperative hematocrit level, platelets, presence of disseminated cancer, planned hysterectomy approach, and procedures accurately predicted blood transfusion with good discriminatory ability (C-statistic=0.80 [P<.001]; C-statistic=0.69 [P<.001] for derivation and validation datasets, respectively) and calibration (Hosmer-Lemeshow goodness-of-fit, P=.081; P=.56 for derivation and validation datasets, respectively).

CONCLUSION

Patients who undergo hysterectomy for ovarian cancer experience a high incidence of blood transfusions in the perioperative period. Preoperative risk factors and planned surgical procedures can be used in our transfusion risk score to help predict anticipated blood requirements.

Anemia and Iron Deficiency in Cancer Patients: Role of Iron Replacement Therapy

Anemia in cancer patients is quite common, with remarkable negative impacts on quality of life and overall prognosis. The pathogenesis is complex and typically multifactorial, with iron deficiency (ID) often being a major and potentially treatable contributor. In turn, ID in cancer patients can be due to multiple concurring mechanisms, including bleeding (e.g., in gastrointestinal cancers or after surgery), malnutrition, medications, and hepcidin-driven iron sequestration into macrophages with subsequent iron-restricted erythropoiesis. Indeed, either absolute or functional iron deficiency (AID or FID) can occur. While for absolute ID there is a general consensus regarding the laboratory definition (that is ferritin levels <100 ng/mL ± transferrin saturation (TSAT) <20%), a shared definition of functional ID is still lacking. Current therapeutic options in cancer anemia include iron replacement, erythropoietic stimulating agents (ESAs), and blood transfusions. The latter should be kept to a minimum, because of concerns regarding risks, costs, and limited resources. Iron therapy has proved to be a valid approach to enhance efficacy of ESAs and to reduce transfusion need. Available guidelines focus mainly on patients with chemotherapy-associated anemia, and generally suggest intravenous (IV) iron when AID or FID is present. However, in the case of FID, the upper limit of ferritin in association with TSAT <20% at which iron should be prescribed is a matter of controversy, ranging up to 800 ng/mL. An increasingly recognized indication to IV iron in cancer patients is represented by preoperative anemia in elective oncologic surgery. In this setting, the primary goal of treatment is to decrease the need of blood transfusions in the perioperative period, rather than improving anemia-related symptoms as in chemotherapy-associated anemia. Protocols are mainly based on experiences of Patient Blood Management (PBM) in non-oncologic surgery, but no specific guidelines are available for oncologic surgery. Here we discuss some possible approaches to the management of ID in cancer patients in different clinical settings, based on current guidelines and recommendations, emphasizing the need for further research in the field.

Decreased Hemolysis and Improved Platelet Function in Blood Components Washed With Plasma-Lyte A Compared to 0.9% Sodium Chloride

OBJECTIVES

Washing cellular blood products is accepted to ameliorate repeated severe allergic reactions but is associated with RBC hemolysis and suboptimal platelet function. We compared in vitro hemolysis and platelet function in blood components after washing with Plasma-Lyte A (PL-A) vs normal saline (NS).

METHODS

RBC (n = 14) were washed/resuspended in NS or PL-A. Free hemoglobin and heme were determined at 0, 24, 48, and 72 hours. Platelet concentrates (PCs; n = 21) were washed with NS or PL-A and resuspended in same washing solution (n = 13) or ABO-identical plasma (n = 8). Platelet aggregation and spreading were evaluated.

RESULTS

The 24-hour free hemoglobin and heme levels were higher in NS (P < .05). Improved platelet function was observed in PL-A-washed PCs (P < .001).

DISCUSSION

PL-A showed less RBC hemolysis and better platelet function than NS. Whether such differences would occur in vivo is unknown.

Intra-operative cell salvage in urological surgery: a systematic review and meta-analysis of comparative studies

OBJECTIVE

To evaluate systematically the safety and efficacy of intra-operative cell salvage (ICS) in urology.

METHODS

A search of Medline, Embase and Cochrane Library to August 2017 was performed using methods pre-published on PROSPERO. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Eligible titles were comparative studies published in English that used ICS in urology. Primary outcomes were allogeneic transfusion rates (ATRs) and tumour recurrence. Secondary outcomes were complications and cost.

RESULTS

Fourteen observational studies were identified, with a total of 4 536 patients. ICS was compared with no the blood conservation technique (seven studies), preoperative autologous donation (PAD; five studies) or both (two studies). Cohorts underwent open prostatectomy (11 studies), open cystectomy (two studies) or open partial nephrectomy (one study). Meta-analysis was possible only for ATRs within prostatectomy studies. In this setting, ICS reduced ATR compared with no the blood conservation technique (odds ratio [OR] 0.34, 95% confidence interval [CI] 0.15-0.76) but not PAD (OR 0.76, 95% CI 0.39-1.31). In the non-prostatectomy setting, ATRs amongst patients who underwent ICS were significantly higher or similar in one and two studies, respectively. Tumour recurrence was found to be significantly less common (two studies), similar (eight studies) or not measured (four studies). All six studies reporting complications found no difference in their ICS cohorts. Regarding cost, one study from 1995 found ICS more expensive than PAD, while two more recent studies found ICS to be cheaper than no blood conservation technique. As a result of inter-study heterogeneity, meta-analyses were not possible for recurrence, complications or cost.

CONCLUSION

Low-level evidence exists that, compared with other blood conservation techniques, ICS reduces ATR and cost while not affecting complications. It does not appear to increase tumour recurrence post-prostatectomy, although follow-up durations were short. Small study sizes and short follow-ups mean conclusions cannot be drawn with regard to recurrence after nephrectomy or cystectomy. Randomized trials with long-term follow-up evaluating ICS in urology are required.

Blood Product Administration in the Critical Care and Perioperative Settings

The critical care and perioperative settings are high consumers of blood products, with multiple units and different products often given to an individual patient. The recommendation of this review is always to consider the risks and benefits for a specific blood product for a specific patient in a specific clinical setting. Optimize patient status by treating anemia and preventing the need for red blood cell transfusion. Consider other options for correction of anemia and coagulation disorders and use an imperative non-overtransfusion policy for all blood products.

Transfusion practice patterns in patients with anemia receiving myelosuppressive chemotherapy for nonmyeloid cancer: results from a prospective observational study

Purpose

The decision to prescribe packed red blood cell (PRBC) transfusions in patients with chemotherapy-induced anemia (CIA) includes assessment of clinical features such as the patient’s cancer type and treatment regimen, severity of anemia symptoms, and presence of comorbidities. We examined contemporary transfusion practices in patients with nonmyeloid cancer and CIA.

Methods

Key inclusion criteria were age ≥ 18 years with nonmyeloid cancer, receiving first/second-line myelosuppressive chemotherapy, baseline hemoglobin (Hb) ≤ 10.0 g/dL, and planned to receive ≥ 1 PRBC transfusions. Exclusion criteria were receipt of erythropoiesis-stimulating agents within 8 weeks of screening and/or chronic renal insufficiency. Data were collected from patients’ medical records, laboratory values, and physician/provider questionnaires. Proportion of patients for each clinical consideration leading to a decision to prescribe a PRBC transfusion and 95% exact binomial confidence intervals were determined.

Results

The study enrolled 154 patients at 18 sites in USA; 147 (95.5%) received a PRBC transfusion. Fatigue was the most common symptom affecting the decision to prescribe a PRBC transfusion (101 [69.2%] patients). Of the three reasons selected as primary considerations for prescribing a PRBC transfusion, anemia symptoms (106 [72.1%] patients) was the most frequently reported, followed by Hb value (37 [25.2%] patients) and medical history (4 [2.7%] patients).

Conclusions

In this study, the primary consideration for prescribing a PRBC transfusion was anemia symptoms in 72.1% of patients, with only 25.2% of patients prescribed a transfusion based exclusively on Hb value. Results indicate that clinical judgment and patient symptoms, not just Hb value, were used in decisions to prescribe PRBC transfusions.

Electronic supplementary material

The online version of this article (10.1007/s00520-017-4035-7) contains supplementary material, which is available to authorized users.

Short-term effect of preoperative intravenous iron therapy in colorectal cancer patients with anemia: results of a cohort study

BACKGROUND

In the treatment of preoperative anemia, which is associated with increased postoperative morbidity, iron supplementation can replace blood transfusion and erythropoiesis-stimulating agents. The aim of this study was to assess the efficacy of preoperative intravenous (IV) iron infusion in optimizing hemoglobin (Hb) levels in anemic colorectal cancer patients.

STUDY DESIGN AND METHODS

A retrospective cohort study was performed on patients who underwent surgery for colorectal cancer between 2010 and 2016 in a single teaching hospital. The primary outcome measure, the change in Hb level, was assessed by comparing anemic patients receiving usual care (UC; i.e. no iron therapy and no blood transfusion) with anemic patients receiving IV iron therapy (no blood transfusion).

RESULTS

A total of 758 patients with colorectal cancer were eligible, of whom 318 (41.9%) had anemia. The IV and the UC groups included 52 and 153 patients with mean Hb levels at diagnosis of 6.3 and 6.9 mmol/L, respectively. In the IV group, preoperative Hb level was significantly increased compared to the UC group (0.65 mmol/L vs. 0.10 mmol/L, p < 0.001). High increase in Hb level after iron infusion was associated with initial higher transferrin and lower ferritin levels (high vs. poor responders: median transferrin 2.9 g/L vs. 2.7 g/L, median ferritin 12 µg/L vs. 27 µg/L).

CONCLUSION

Implementation of IV iron therapy in anemic colorectal cancer patients leads to a distinct increase of preoperative Hb level. IV iron therapy is most effective in patients presenting with more severe anemia, and with higher transferrin and lower ferritin levels, markers for an absolute iron deficiency (ID), compared to functional ID.

Outcomes of red blood cell transfusions prescribed in organ donors by the Digital Intern, an electronic decision support algorithm

BACKGROUND

The Digital Intern (DI) is an electronic decision support tool for the management of organ donors. One algorithm determines the dose, in units of red blood cells to be transfused, based on hematocrit (Hct) thresholds and targets. The effectiveness of the transfusion dose calculated by the DI in terms of achieving the selected Hct target and the duration of the targeted dose is not known.

STUDY DESIGN AND METHODS

This was a retrospective study to describe the outcomes of transfusions prescribed by the DI. Pre- and posttransfusion Hct levels were compared to define response and all posttransfusion Hct values were plotted to evaluate the duration of the prescribed dose.

RESULTS

A total of 120 organ donors were studied and 22 donors had 28 transfusions (six were transfused twice). The transfused donors were a mix of trauma and medical admissions and brain death and cardiac death donors. The transfusion target of 24% Hct was attained in 96% of transfusions. The mean number of units transfused was 1.4 and the mean time from transfusion to procurement was 19.8 hours. There was a decline in Hct over time after transfusion in all but one case with a mean decline of 1.9% Hct over 13 hours. Six donors were transfused twice, likely due to a longer donor time period (41.7 hr vs. 27 hr).

CONCLUSIONS

The DI provided transfusion dosing that achieved the desired threshold in the majority of organ donors transfused. Ongoing work focuses on application of this technology to transfusions in general patient populations.

Allogenic Blood Transfusion Is an Independent Predictor of Poorer Peri-operative Outcomes and Reduced Long-Term Survival after Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: a Review of 936 Cases

INTRODUCTION

There is a paucity of data on the impact of allogenic blood transfusion (ABT) on morbidity and survival outcomes after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

METHODS

Nine hundred and thirty-five consecutive CRS/HIPEC procedures were performed between 1996 and 2016 at a high-volume institution in Sydney, Australia. Of these, 337(36%) patients required massive ABT (MABT) (≥5 units). Peri-operative complications were graded according to the Clavien-Dindo classification. The association of concomitant MABT with 21 peri-operative outcomes and overall survival (OS) was assessed using univariate and multivariate analyses.

RESULTS

In-hospital mortality was 1.8%. Patients requiring MABT had more extensive disease as reflected by a higher peritoneal cancer index (≥17) (70 vs. 29%, p < 0.001) and longer operative times (≥9 h) (82 vs. 35%, p < 0.001). After accounting for confounding factors, MABT was associated with in-hospital mortality (relative risk (RR), 7.72; 95% confidence interval (CI), 1.35-10.11; p = 0.021) and grade III/IV morbidity (RR, 2.05; 95% CI, 1.42-2.95; p < 0.001). MABT was associated with an increased incidence of prolonged hospital stay (≥28 days) (RR, 1.86; 95% CI, 1.26-2.74; p = 0.002) and intensive care unit stay (≥4 days) (RR, 1.83; 95% CI, 1.24-2.70, p = 0.002). It was also associated with a significant OS in patients with colorectal cancer peritoneal carcinomatosis (RR 4.49; p < 0.001) and pseudomyxoma peritonei (RR, 4.37; p = 0.026), but not appendiceal cancer (p = 0.160).

CONCLUSION

MABT is an independent predictor for poorer peri-operative outcomes including in-hospital mortality and grade III/IV morbidity. It may also compromise long-term survival, particularly in patients with colorectal cancer peritoneal carcinomatosis.

Higher vs. lower haemoglobin threshold for transfusion in septic shock: subgroup analyses of the TRISS trial

BACKGROUND

Using a restrictive transfusion strategy appears to be safe in sepsis, but there may be subgroups of patients who benefit from transfusion at a higher haemoglobin level. We explored if subgroups of patients with septic shock and anaemia had better outcome when transfused at a higher vs. a lower haemoglobin threshold.

METHODS

In post-hoc analyses of the full trial population of 998 patients from the Transfusion Requirements in Septic Shock (TRISS) trial, we investigated the intervention effect on 90-day mortality in patients with severe comorbidity (chronic lung disease, haematological malignancy or metastatic cancer), in patients who had undergone surgery (elective or acute) and in patients with septic shock as defined by the new consensus definition: lactate above 2 mmol/l and the need for vasopressors to maintain a mean arterial pressure above 65 mmHg.

RESULTS

The baseline characteristics were mostly similar between the two intervention groups in the different subgroups. There were no differences in the intervention effect on 90-day mortality in patients with chronic lung disease (test of interaction P = 0.31), haematological malignancy (P = 0.47), metastatic cancer (P = 0.51), in those who had undergone surgery (P = 0.99) or in patients with septic shock by the new definition (P = 0.20).

CONCLUSION

In exploratory analyses of a randomized trial in patients with septic shock and anaemia, we observed no survival benefit in any subgroups of transfusion at a haemoglobin threshold of 90 g/l vs. 70 g/l.

Restrictive versus liberal red blood cell transfusion strategies for people with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without haematopoietic stem cell support

BACKGROUND

Many people diagnosed with haematological malignancies experience anaemia, and red blood cell (RBC) transfusion plays an essential supportive role in their management. Different strategies have been developed for RBC transfusions. A restrictive transfusion strategy seeks to maintain a lower haemoglobin level (usually between 70 g/L to 90 g/L) with a trigger for transfusion when the haemoglobin drops below 70 g/L), whereas a liberal transfusion strategy aims to maintain a higher haemoglobin (usually between 100 g/L to 120 g/L, with a threshold for transfusion when haemoglobin drops below 100 g/L). In people undergoing surgery or who have been admitted to intensive care a restrictive transfusion strategy has been shown to be safe and in some cases safer than a liberal transfusion strategy. However, it is not known whether it is safe in people with haematological malignancies.

OBJECTIVES

To determine the efficacy and safety of restrictive versus liberal RBC transfusion strategies for people diagnosed with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without a haematopoietic stem cell transplant (HSCT).

SEARCH METHODS

We searched for randomised controlled trials (RCTs) and non-randomised trials (NRS) in MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1982), Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 6), and 10 other databases (including four trial registries) to 15 June 2016. We also searched grey literature and contacted experts in transfusion for additional trials. There was no restriction on language, date or publication status.

SELECTION CRITERIA

We included RCTs and prospective NRS that evaluated a restrictive compared with a liberal RBC transfusion strategy in children or adults with malignant haematological disorders or undergoing HSCT.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified six studies eligible for inclusion in this review; five RCTs and one NRS. Three completed RCTs (156 participants), one completed NRS (84 participants), and two ongoing RCTs. We identified one additional RCT awaiting classification. The completed studies were conducted between 1997 and 2015 and had a mean follow-up from 31 days to 2 years. One study included children receiving a HSCT (six participants), the other three studies only included adults: 218 participants with acute leukaemia receiving chemotherapy, and 16 with a haematological malignancy receiving a HSCT. The restrictive strategies varied from 70 g/L to 90 g/L. The liberal strategies also varied from 80 g/L to 120 g/L.Based on the GRADE rating methodology the overall quality of the included studies was very low to low across different outcomes. None of the included studies were free from bias for all 'Risk of bias' domains. One of the three RCTs was discontinued early for safety concerns after recruiting only six children, all three participants in the liberal group developed veno-occlusive disease (VOD). Evidence from RCTsA restrictive RBC transfusion policy may make little or no difference to: the number of participants who died within 100 days (two trials, 95 participants (RR: 0.25, 95% CI 0.02 to 2.69, low-quality evidence); the number of participants who experienced any bleeding (two studies, 149 participants; RR:0.93, 95% CI 0.73 to 1.18, low-quality evidence), or clinically significant bleeding (two studies, 149 participants, RR: 1.03, 95% CI 0.75 to 1.43, low-quality evidence); the number of participants who required RBC transfusions (three trials; 155 participants: RR: 0.97, 95% CI 0.90 to 1.05, low-quality evidence); or the length of hospital stay (restrictive median 35.5 days (interquartile range (IQR): 31.2 to 43.8); liberal 36 days (IQR: 29.2 to 44), low-quality evidence).We are uncertain whether the restrictive RBC transfusion strategy: decreases quality of life (one trial, 89 participants, fatigue score: restrictive median 4.8 (IQR 4 to 5.2); liberal median 4.5 (IQR 3.6 to 5) (very low-quality evidence); or reduces the risk of developing any serious infection (one study, 89 participants, RR: 1.23, 95% CI 0.74 to 2.04, very low-quality evidence).A restrictive RBC transfusion policy may reduce the number of RBC transfusions per participant (two trials; 95 participants; mean difference (MD) -3.58, 95% CI -5.66 to -1.49, low-quality evidence). Evidence from NRSWe are uncertain whether the restrictive RBC transfusion strategy: reduces the risk of death within 100 days (one study, 84 participants, restrictive 1 death; liberal 1 death; very low-quality evidence); decreases the risk of clinically significant bleeding (one study, 84 participants, restrictive 3; liberal 8; very low-quality evidence); or decreases the number of RBC transfusions (adjusted for age, sex and acute myeloid leukaemia type geometric mean 1.25; 95% CI 1.07 to 1.47 - data analysis performed by the study authors)No NRS were found that looked at: quality of life; number of participants with any bleeding; serious infection; or length of hospital stay.No studies were found that looked at: adverse transfusion reactions; arterial or venous thromboembolic events; length of intensive care admission; or readmission to hospital.

AUTHORS' CONCLUSIONS

Findings from this review were based on four studies and 240 participants.There is low-quality evidence that a restrictive RBC transfusion policy reduces the number of RBC transfusions per participant. There is low-quality evidence that a restrictive RBC transfusion policy has little or no effect on: mortality at 30 to 100 days, bleeding, or hospital stay. This evidence is mainly based on adults with acute leukaemia who are having chemotherapy. Although, the two ongoing studies (530 participants) are due to be completed by January 2018 and will provide additional information for adults with haematological malignancies, we will not be able to answer this review's primary outcome. If we assume a mortality rate of 3% within 100 days we would need 1492 participants to have a 80% chance of detecting, as significant at the 5% level, an increase in all-cause mortality from 3% to 6%. Further RCTs are required in children.