Red Blood Cell Transfusion Thresholds Research Articles

Peripheral perfusion index stratifies risk in patients with intraoperative anemia: A multicentre cohort study

Study objectiveEvidence for red blood cell (RBC) transfusion thresholds in the intraoperative setting is limited, and current perioperative recommendations may not correspond with individual intraoperative physiological demands. Hemodynamics relevant for the decision to transfuse may include peripheral perfusion index (PPI). The objective of this prospective study was to assess the associations of PPI and hemoglobin levels with the risk of postoperative morbidity and mortality. DesignMulticenter cohort study. SettingBispebjerg and Hvidovre University Hospitals, Copenhagen, Denmark. PatientsWe included 741 patients who underwent acute high risk abdominal surgery or hip fracture surgery. InterventionsNo interventions were carried out. MeasurementsPrincipal values collected included measurements of peripheral perfusion index and hemoglobin values. MethodsThe study was conducted using prospectively obtained data on adults who underwent emergency high-risk surgery. Subjects were categorized into high vs. low subgroups stratified by pre-defined PPI levels (PPI: > 1.5 vs. < 1.5) and Hb levels (Hb: > 9.7 g/dL vs. < 9.7 g/dL). The study assessed mortality and severe postoperative complications within 90 days. Main resultsWe included 741 patients. 90-day mortality was 21% (n = 154), frequency of severe postoperative complications was 31% (n = 231).Patients with both low PPI and low Hb had the highest adjusted odds ratio for both 90-day severe postoperative complications (2.95, [1.62–5.45]) and 90-day mortality (3.13, [1.45–7.11]).A comparison of patients with low PPI and low Hb to those with high PPI and low Hb detected significantly higher 90-day mortality risk in the low PPI and low Hb group (OR 8.6, [1.57–162.10]). ConclusionHigh PPI in acute surgical patients who also presents with anemia was associated with a significantly better outcome when compared with patients with both low PPI and anemia. PPI should therefore be further investigated as a potential parameter to guide intraoperative RBC transfusion therapy.

Improvement of Transfusion Practice in Cardiothoracic Surgery Through Implementing a Patient Blood Management Program.

In this study, we examined the impact of a patient blood management (PBM) program on red blood cell (RBC) transfusion practices in cardiothoracic surgery. The PBM program had 3 components: monitoring transfusions through an order communication system checklist, educating the medical team about PBM, and providing feedback to ordering physicians on the appropriateness of transfusion. The retrospective analysis examined changes in the hemoglobin levels triggering transfusion and the proportions of appropriate RBC transfusions before, during, and after PBM implementation. Further analysis was focused on patients undergoing cardiac surgery, with outcomes including 30-day mortality, durations of intensive care unit and hospital stays, and rates of pneumonia, sepsis, and wound complications. The study included 2,802 patients admitted for cardiothoracic surgery. After the implementation of PBM, a significant decrease was observed in the hemoglobin threshold for RBC transfusion. This threshold dropped from 8.7 g/dL before PBM to 8.3 g/dL during the PBM education phase and 8.0 g/dL during the PBM feedback period. Additionally, the proportion of appropriate RBC transfusions increased markedly, from 23.9% before PBM to 34.9% and 58.2% during the education and feedback phases, respectively. Among the 381 patients who underwent cardiac surgery, a significant reduction was noted in the length of hospitalization over time (p<0.001). However, other clinical outcomes displayed no significant differences. PBM implementation effectively reduced the hemoglobin threshold for RBC transfusion and increased the rate of appropriate transfusion in cardiothoracic surgery. Although transfusion practices improved, clinical outcomes were comparable to those observed before PBM implementation.

Red blood cell transfusion in neurocritical patients: a systematic review and meta-analysis

BackgroundAnemia can lead to secondary brain damage by reducing arterial oxygen content and brain oxygen supply. Patients with acute brain injury have impaired self-regulation. Brain hypoxia may also occur even in mild anemia. Red blood cell (RBC) transfusion is associated with increased postoperative complications, poor neurological recovery, and mortality in critically ill neurologic patients. Balancing the risks of anemia and red blood cell transfusion-associated adverse effects is challenging in neurocritical settings.MethodsWe searched the Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and MEDLINE (PubMed) from inception to January 31, 2024. We included all randomized controlled trials (RCTs) assessing liberal versus restrictive RBC transfusion strategies in neurocritical patients. We included all relevant studies published in English. The primary outcome was mortality at intensive care unit (ICU), discharge, and six months.ResultsOf 5195 records retrieved, 84 full-text articles were reviewed, and five eligible studies were included. There was no significant difference between the restrictive and liberal transfusion groups in ICU mortality (RR: 2.53, 95% CI: 0.53 to 12.13), in-hospital mortality (RR: 2.34, 95% CI: 0.50 to 11.00), mortality at six months (RR: 1.42, 95% CI: 0.42 to 4.78) and long-term mortality (RR: 1.22, 95% CI: 0.64 to 2.33). The occurrence of neurological adverse events and most major non-neurological complications was similar in the two groups. The incidence of deep venous thrombosis was lower in the restrictive strategy group (RR: 0.41, 95% CI: 0.18 to 0.91).ConclusionsDue to the small sample size of current studies, the evidence is insufficiently robust to confirm definitive conclusions for neurocritical patients. Therefore, further investigation is encouraged to define appropriate RBC transfusion thresholds in the neurocritical setting.

Bleeding Risk Factors in Thrombocytopenic Patients with Hematologic Malignancies

Introduction Despite prophylactic platelet transfusions, World Health Organization (WHO) grade ≥ 2 bleeding occurs in 50 to 70% of patients with hematologic malignancies and hypoproliferative thrombocytopenia secondary to therapy and/or underlying disease (Gernsheimer et al, Blood 2022). Anemia (hematocrit, HCT ≤ 25%), coagulopathy (activated partial thromboplastin time ≥ 30s, international normalized ratio ≥ 1.2), and platelet count ≤ 5000/µl were independently associated with increased risk of bleeding in the PLADO (platelet dose) trial of 1272 patients with hypoproliferative thrombocytopenia treated between 2004 to 2007 (Uhl et al, Blood 2017). Updated data on bleeding outcomes and risk of bleeding is lacking. Methods We performed a post-hoc analysis of bleeding outcomes and bleeding risk factors in 330 patients with hematologic malignancy and hypoproliferative thrombocytopenia from therapy and/or underlying disease randomized at 3 institutions to receive either tranexamic acid (TXA) or placebo in the double-blinded, multicenter American Trial to Evaluate Tranexamic Acid Therapy in Thrombocytopenia (A-TREAT) (Gernsheimer et al, Blood 2022). Patients received prophylactic platelet transfusions for a platelet count of ≤ 10,000/µl and WHO grade bleeding was assessed daily for 30 days after a platelet count ≤ 30,000/µl and study drug was started. Study drug was discontinued when platelet count was ≥ 30,000/ul for 46 hours without platelet transfusion support or until a maximum of 30 days after treatment activation, whichever came first. Red blood cell (RBC) transfusion was given according to local standard of care. Cox proportional hazards regression with time-varying covariates was used to assess the association of patient characteristics with the risk of a first major (grade 2+) bleeding event. HCT, platelet count, inpatient vs. outpatient status, steroid treatment, and fever were recorded daily. Patients were censored at the first of time of withdrawal, death, or day 30. Results WHO grade ≥ 2 bleeding occurred in 46% of patients overall with no difference between the TXA and placebo groups (TXA 44% versus placebo 47%, p=0.66). Bleeding rates were highest in allogeneic stem cell transplant patients, followed by chemotherapy, followed by autologous stem cell transplant. Overall bleeding rates by organ system showed oral and nasal (18%), skin (17%), gastrointestinal (11%), and genitourinary (11%) bleeding (Table 1). WHO grade ≥ 2 vaginal bleeding occurred in 28% of patients of childbearing potential despite widespread use of hormonal suppression. In a proportional hazards regression model of time to first bleeding event, undergoing allogeneic stem cell transplant was associated with a non-significant increased hazard of bleeding vs chemotherapy (HR 1.32, 95% CI 0.92-1.89), whereas autologous transplant had significantly lower hazard of bleeding vs chemotherapy (HR 0.39, 95% CI 0.20-0.76) (Table 2). HCT &amp;lt; 21% was associated with increased bleeding risk even after adjusting for severe thrombocytopenia (HR 2.71, 29% CI 1.37, 5.36). Platelet count &amp;lt; 5000/µl was also associated with increased risk (HR 3.33, 95% CI 1.67-6.61). Inpatient status, presence of fever, and age did not significantly impact risk of first bleed. Conclusions The overall rate of WHO grade &amp;gt;2 bleeding was similar to historical literature with lower rates of gastrointestinal bleeding than previously reported (31% in PLADO). Vaginal bleeding was common despite standard use of hormonal suppression in patients of childbearing potential. Platelet count &amp;lt; 5000/µl remains a risk factor for bleeding. Regardless of platelet count, bleeding risk increased with HCT &amp;lt; 21% suggesting a red blood cell transfusion threshold higher than 21% is unlikely to mitigate bleeding. More investigation is needed on strategies to reduce bleeding in this patient population.

Potential benefits of restrictive transfusion in upper gastrointestinal bleeding: a systematic review and meta-analysis of randomised controlled trials

The optimal red blood cell (RBC) transfusion strategy in acute gastrointestinal bleeding (GIB) is debated. We aimed to assess the efficacy and safety of restrictive compared to liberal transfusion strategies in the GIB population. We searched PubMed, CENTRAL, Embase, and Web of Science for randomised controlled trials on 15.01.2022 without restrictions. Studies comparing lower to higher RBC transfusion thresholds after GIB were eligible. We used the random effect model and calculated pooled mean differences (MD), risk ratios (RR) and proportions with 95% confidence intervals (CI) to calculate the overall effect size. The search yielded 3955 hits. All seven eligible studies reported on the upper GIB population. Restrictive transfusion did not increase the in-hospital- (RR: 0.94; CI 0.46, 1.94) and 30-day mortality (RR: 0.71; CI 0.35, 1.45). In-hospital- and 28 to 45-day rebleeding rate was also not higher with the restrictive modality (RR: 0.67; CI 0.30, 1.50; RR:0.75; CI 0.49, 1.16, respectively). Results of individual studies showed a lower rate of transfusion reactions and post-transfusion intervention if the transfusion was started at a lower threshold. A haemoglobin threshold > 80 g/L may result in a higher untoward outcome rate. In summary, restrictive transfusion does not appear to lead to a higher rate of significant clinical endpoints. The optimal restrictive transfusion threshold should be further investigated.

Transfusion of red blood cells in venoarterial extracorporeal membrane oxygenation: A multicenter retrospective observational cohort study.

Evidence-based recommendations for transfusion in patients with venoarterial extracorporeal membrane oxygenation (VA ECMO) are scarce. The current literature is limited to single-center studies with small sample sizes, therefore complicating generalizability. This study aims to create an overview of red blood cell (RBC) transfusion in VA ECMO patients. This international mixed-method study combined a survey with a retrospective observational study in 16 centers. The survey inventoried local transfusion guidelines. Additionally, retrospective data of all adult patients with a VA ECMO run >24 h (January 2018 until July 2019) was collected of patient, ECMO, outcome, and daily transfusion parameters. All patients that received VA ECMO for primary cardiac support were included, including surgical (i.e., post-cardiotomy) and non-surgical (i.e., myocardial infarction) indications. The primary outcome was the number of RBC transfusions per day and in total. Univariable logistic regressions and a generalized linear mixed model (GLMM) were performed to assess factors associated with RBC transfusion. Out of 419 patients, 374 (89%) received one or more RBC transfusions. During a median ECMO run of 5 days (1st-3rd quartile 3-8), patients received a median total of eight RBC units (1st-3rd quartile 3-17). A lower hemoglobin (Hb) prior to ECMO, longer ECMO-run duration, and hemorrhage were associated with RBC transfusion. After correcting for duration and hemorrhage using a GLMM, a different transfusion trend was found among the regimens. No unadjusted differences were found in overall survival between either transfusion status or the different regimens, which remained after adjustment for potential confounders. RBC transfusion in patients on VA ECMO is very common. The sum of RBC transfusions increases rapidly after ECMO initiation, and is dependent on the Hb threshold applied. This study supports the rationale for prospective studies focusing on indications and thresholds for RBC transfusion.

A pilot randomized study for optimal red cell transfusion in acute myeloid leukemia patients with intensive chemotherapy.

Although blood transfusion is fundamental throughout the course of hematologic malignancies, acute myeloid leukemia (AML) patients requiring intensive chemotherapy are left at the edges of patient blood management programs because current guidelines do not have established recommendations for red blood cell (RBC) transfusion threshold in patients treated for hematological disorders with anemia and accompanied severe thrombocytopenia. To provide answers for the trigger and doses of ideal RBC transfusion in such situation, we conducted this prospective randomized trial. Newly diagnosed non-acute promyelocytic AML patients undergoing chemotherapy were considered eligible for enrollment. Patients were randomized into 4 groups using a 2 by 2 factorial design, according to the RBC transfusion trigger (hemoglobin [Hb], 7 vs 8 g/dL) and the number of units per transfusion episode (quantity, single vs double-unit). Initially 91 patients were randomized into 4 groups, but the protocol adherence rate was 90.1%. Hb trigger did not affect the amount of RBC transfusion required during treatment. Patients receiving RBC transfusion at Hb <7 g/dL used a median of 4 units of RBC (range 0-12), and those receiving transfusion at Hb <8 g/dL also used a median of 4 units of RBC (range 0-24) (p=0.305). The number of RBC units per transfusion did not affect the total amount of RBC transfusion required during treatment. AML treatment outcomes and bleeding events did not differ across the 4 groups. This study demonstrated the feasibility for restrictive RBC transfusion (Hb <7 g/dL, RBC 1 unit) in AML patients undergoing chemotherapy, regardless of chemotherapy intensity.

Association of Postoperative Drift in Hemoglobin With Mortality After Brain Tumor Craniotomy.

Postoperative downward drift in hemoglobin (Hb) concentration may be associated with complications and death, even if nadir Hb remains more than the red blood cell transfusion threshold of 7 g/dL. To assess whether postoperative Hb drift in patients undergoing brain tumor craniotomy influences mortality in the immediate perioperative period. This retrospective cohort study included patients undergoing craniotomy for brain tumors. We defined no postoperative Hb decrease, mild decrease, moderate decrease, and severe decrease as postoperative Hb drift of ≤25%, 26% to 50%, 51% to 75%, and >75%, respectively. The primary outcome was 30-day mortality after craniotomy. This study included 8159 patients who underwent a craniotomy for brain tumors. Compared with patients with no postoperative Hb drift, the odds of postoperative mortality at 30 days increased in patients with mild postoperative Hb drift (adjusted odds ratio [OR] 2.47, 95% CI 1.72-3.56), moderate drift (adjusted OR 6.56, 95% CI 3.42-12.59), and severe drift (adjusted OR 12.33, 95% CI 3.48-43.62). When postoperative Hb drift was analyzed as a continuous variable, for each 10% increase in Hb drift, the adjusted OR of postoperative mortality at 30 days was 1.46 (95% CI 1.31-1.63). In patients undergoing brain tumor craniotomy, a small postoperative Hb drift was associated with increased odds of postoperative mortality at 30 days, even if the nadir Hb level remained greater than the red blood cell transfusion threshold of 7 g/dL. Future randomized clinical trials of perioperative transfusion practices may examine the effect of both nadir Hb and Hb drift.

Practice variability in the perioperative management of pediatric moyamoya disease in North America

BackgroundRevascularization surgery decreases the long-term risk of stroke in children with moyamoya but carries an increased risk of perioperative ischemic events. Evidence-based approaches to safe perioperative management of children with moyamoya are limited. We aimed to understand practice variability in perioperative moyamoya care. MethodsNeurologists, neurosurgeons, and intensivists practicing in North America with expertise in perioperative pediatric moyamoya care participated in a 138-item anonymous survey focused on interdisciplinary perioperative care surrounding indirect revascularization surgery. ResultsMany perioperative care practices vary substantially between participants. Timing of resumption of antiplatelet therapy postoperatively, choice of sedative agents and vasopressors, goal blood pressures, rate and duration of intravenous fluid administration, and red blood cell transfusion thresholds are among the most variable practices. ConclusionsThis practice variability survey highlights several important knowledge gaps and areas of equipoise that should be targets for future investigation and consensus-building efforts.

Editor's Choice Articles for February.

Editor's Choice Articles for February.

Evaluation of red blood cell transfusion threshold in the management of brain-dead organ donors

The disparity between the demand and supply of organs has necessitated an expansion of the criteria for organ donation. Consequently, numerous guidelines have been proposed for managing brain-dead organ donors (BDODs) to improve their organ function and the organ procurement rate. Therefore, we aimed to evaluate the previously recommended threshold for red blood cell transfusion in BDODs. Medical records of BDODs were retrospectively reviewed from January 2012 to December 2021. We enrolled BDODs who stayed for more than 24 hours at an hospital organ procurement organization. We analyzed their organ function and the rate of organ procurement according to the hemoglobin concentration. A total of 111 BDODs were enrolled and divided into the following 2 groups: hemoglobin (Hb) ≥ 10 g/dL (45.0 %) and Hb < 10 g/dL (55.0 %). There were no significant differences between the groups in the total bilirubin, creatinine, arterial blood lactate, and the rate of organ procurement. A correlation analysis did not reveal any association between the hemoglobin concentration and organ function of the BDODs. Hemoglobin concentration of 10 g/dL cannot be considered a threshold for red blood cell transfusion. Furthermore, organ function is not correlated with a hemoglobin concentration > 7 g/dL. Restrictive transfusion strategy is appropriate for BDOD management.

Transfusion Guidelines in Traumatic Brain Injury: A Systematic Review and Meta-Analysis of the Currently Available Evidence.

Our study aims to provide a synthesis of the best available evidence on the hemoglobin (hgb) red blood cell (RBC) transfusion thresholds in adult traumatic brain injury (TBI) patients, as well as describing the risk factors and outcomes associated with RBC transfusion in this population. A systematic review and meta-analysis was conducted using PubMed, Google Scholar, and Web of Science electronic databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to assess articles discussing RBC transfusion thresholds and describe complications secondary to transfusion in adult TBI patients in the perioperative period. Fifteen articles met search criteria and were reviewed for analysis. Compared to non-transfused, TBI patients who received transfusion tended to be primarily male patients with worse Injury Severity Score (ISS) and Glasgow Coma Scale. Further, the meta-analysis corroborated that transfused TBI patients are older (p = 0.04), have worse ISS scores (p = 0.001), receive more units of RBCs (p = 0.02), and have both higher mortality (p < 0.001) and complication rates (p < 0.0001). There were no differences identified in rates of hypertension, diabetes mellitus, and Abbreviated Injury Scale scores. Additionally, whereas many studies support restrictive (hgb <7 g/dL) transfusion thresholds over liberal (hgb <10 g/dL), our meta-analysis revealed no significant difference in mortality between those thresholds (p = 0.79). Current Class B/C level III evidence predominantly recommends against a liberal transfusion threshold of 10 g/dL for TBI patients (Class B/C level III), but our meta-analysis found no difference in survival between groups. There is evidence suggesting that an intermediate threshold between 7 and 9 g/dL, reflecting the physiological oxygen needs of cerebral tissue, may be worth exploring.

A Retrospective Review of Red Blood Cell Transfusion Practices in a Rural Community Hospital System

Introduction: Anemia is associated with increased length of stay and mortality in hospitalized patients. Red blood cell (RBC) transfusions could be lifesaving intervention and are generally used as a stabilizing measure until underlying etiology of anemia is identified and corrected. However, RBC transfusions have several adverse effects which occasionally could be life-threatening, including transfusion associated infections, immunologic reactions, volume overload, electrolyte imbalances, and iron overload. The decision on RBC transfusions should be based on patient's clinical status and physician's judgment, supported by data from randomized trials. Methods: In efforts to improve RBC transfusion practices in Northern Arizona Healthcare (NAH) facilities, all RBC transfusions between 01/01/2021 and 03/31/2022 were evaluated. Based on randomized clinical trial data, the following RBC transfusion thresholds were considered: Hemoglobin (Hgb) <8 g/dL for hospitalized anemic patients with established cardiovascular disease (CVD) or undergoing surgery, and Hgb <7 g/dL in hemodynamically stable hospitalized patients. Transfusions in pediatric patients, active/suspected blood loss, anemia with hemodynamic instability and massive or recurrent transfusions were excluded from the analysis. For the purpose of this study, RBC transfusion was deemed to be unjustified in cases where only 1 unit of RBC could have been sufficient to raise Hgb level above the specified threshold, however >1 unit was used with no clear justification. Results: A total of 2756 units of RBC transfusions were analyzed in hospitalized patients ages 18-102 years. Three patient groups were identified based on the documented provider justification for RBC transfusions: 1) Hgb <7 g/dL, 2) Hgb <8 g/dL with established CVD or undergoing surgery, 3) "other" who did not meet criteria for the previous groups. In the "other" group, the justification was manually entered by the provider. In the Hgb <7 group, 2004 RBC units were transfused in 1019 patients. Of those, 1440 units were transfused for Hgb level of 6.0-6.9 g/dL in 837 patients, with 273 patients receiving 2-4 units of RBCs when 1 unit could have been sufficient to raise the Hgb level >7 g/dL. Therefore, 303 RBC units were considered unjustified. Also, 83 units were deemed unjustified as they were transfused in 72 patients with pre-transfusion Hgb of ≥7.0 g/dL. In the Hgb <8 group, a total of 711 units were transfused in 500 patients. In the CVD group, 401 units were transfused in 287 patients, of which 260 patients had a Hgb of 7.0-7.9 g/dL. Thirty-four of these patients received 2-3 units when 1 unit was deemed sufficient to increase Hgb >8 (35 unjustified units). Additionally, 5 patients received at least 1 unit of RBC when Hgb was ≥8.0 g/dL (6 unjustified units). In patients undergoing surgery, 213 patients received 310 units. Of those, 150 patients had a Hgb 7.0-7.9 g/dL, 23 of which received >1 units (23 unjustified units). In the group classified as "other", 41 units were transfused in 39 patients. Hgb levels in this group were between 6.7 to 13.3 g/dL. After further evaluation, 18 units transfused in 17 patients were deemed to be unjustified. Discussion: RBC transfusion practices were evaluated in two hospitals in a rural setting in Arizona. From a total of 2756 units, 468 (16.9%) were deemed to be unjustified. The majority of these cases were seen in the Hgb <7 group. This is the first evaluation of RBC transfusion practices at this institution and a stepping stone to implement measures to improve these practices in the future. The next step includes creating an order set module that would not only require providing justification for blood transfusion, but also confirmation of pre-transfusion and desired target Hgb levels. Additionally, it would implement a notification encouraging single unit transfusions when feasible to decrease transfusion associated adverse reactions and cost burden on patients. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Transfusion practice in patients receiving VV ECMO (PROTECMO): a prospective, multicentre, observational study

In patients receiving venovenous (VV) extracorporeal membrane oxygenation (ECMO) packed red blood cell (PRBC) transfusion thresholds are usually higher than in other patients who are critically ill. Available guidelines suggest a restrictive approach, but do not provide specific recommendations on the topic. The main aim of this study was, in a short timeframe, to describe the actual values of haemoglobin and the rate and the thresholds for transfusion of PRBC during VV ECMO. PROTECMO was a multicentre, prospective, cohort study done in 41 ECMO centres in Europe, North America, Asia, and Australia. Consecutive adult patients with acute respiratory distress syndrome (ARDS) who were receiving VV ECMO were eligible for inclusion. Patients younger than 18 years, those who were not able to provide informed consent when required, and patients with an ECMO stay of less than 24 h were excluded. Our main aim was to monitor the daily haemoglobin concentration and the value at the point of PRBC transfusion, as well as the rate of transfusions. The practice in different centres was stratified by continent location and case volume per year. Adjusted estimates were calculated using marginal structural models with inverse probability weighting, accounting for baseline and time varying confounding. Between Dec 1, 2018, and Feb 22, 2021, 604 patients were enrolled (431 [71%] men, 173 [29%] women; mean age 50 years [SD 13·6]; and mean haemoglobin concentration at cannulation 10·9 g/dL [2·4]). Over 7944 ECMO days, mean haemoglobin concentration was 9·1 g/dL (1·2), with lower concentrations in North America and high-volume centres. PRBC were transfused on 2432 (31%) of days on ECMO, and 504 (83%) patients received at least one PRBC unit. Overall, mean pretransfusion haemoglobin concentration was 8·1 g/dL (1·1), but varied according to the clinical rationale for transfusion. In a time-dependent Cox model, haemoglobin concentration of less than 7 g/dL was consistently associated with higher risk of death in the intensive care unit compared with other higher haemoglobin concentrations (hazard ratio [HR] 2·99 [95% CI 1·95-4·60]); PRBC transfusion was associated with lower risk of death only when transfused when haemoglobin concentration was less than 7 g/dL (HR 0·15 [0·03-0·74]), although no significant effect in reducing mortality was reported for transfusions for other haemoglobin classes (7·0-7·9 g/dL, 8·0-9·9 g/dL, or higher than 10 g/dL). During VV ECMO, there was no universally accepted threshold for transfusion, but PRBC transfusion was invariably associated with lower mortality only when done with haemoglobin concentration of less than 7 g/dL. Extracorporeal Life Support Organization.

ONTraC: A 20-Year History of a Successfully Coordinated Provincewide Patient Blood Management Program: Lessons Learned and Goals Achieved

Our understanding of the risks associated with perioperative anemia and transfusion, in terms of increased morbidity and mortality, has evolved over the past 2 decades. By contrast, our understanding of the potential mechanisms of injury and optimal treatment strategies remains incomplete. As such, the important role of effective patient blood management (PBM) programs, which address both the effective treatment of anemia and minimizes the need for red blood cell (RBC) transfusion, is of central importance to optimizing patient care and improving patient outcomes. We report on important clinical outcomes of the Ontario Transfusion Coordinator (ONTraC Program), a network of 25 hospital sites, working in coordination over the past 20 years. Transfusion nurse coordinators were assigned to apply multimodal best practice in PBM (including recommended changes in surgical approach; diagnosis, assessment, and treatment of anemia; and adherence to more restrictive RBC transfusion thresholds). Data were collected on various clinical parameters. We further described lessons learned and difficulties encountered in this multisite PBM initiative. A significant reduction in RBC transfusions was observed for numerous indexed surgeries. For example, RBC transfusion rates for knee arthroplasty decreased from 25% in 2002 to 0.4% in 2020. For coronary artery bypass graft (CABG) surgery, transfusion rates decreased from 60% in 2002 to 27% in 2020. We also observed a decrease in RBC units utilized per transfused patient for knee (2.1 ± 0.5 [2002] vs 1.0 ± 0.6 [2020] units per patient) and CABG surgery (3.3 ± 0.6 [2002] vs 2.3 ± 1.9 [2020] units per patient). These reductions were associated with favorable clinical outcomes, including reduced length of hospital stay (P = .00003) and a reduced rate of perioperative infections (P < .001) for nontransfused versus transfused patients. These advances have been achieved with estimated savings in the tens of millions of dollars annually. Our experience and data support the hypothesis that instituting an integrated network of transfusion nurse coordinators can provide an effective provincewide PBM program, reduce RBC transfusions, improve some patient outcomes, and reduce health care costs, as an example of a "win-win-win" medical program.

Current Understanding of Transfusion-associated Necrotizing Enterocolitis: Review of Clinical and Experimental Studies and a Call for More Definitive Evidence

Introduction:The association between red blood cell (RBC) transfusions and necrotizing enterocolitis (NEC), so-called transfusion-associated NEC (ta-NEC), was first described in 1987. However, further work is needed to confirm a causal relationship, elucidate underlying mechanisms, and develop possible strategies for prevention. We performed an extensive literature search in the databases PubMed, EMBASE, and Scopus.Areas covered:Although multiple retrospective human studies have strongly suggested an association between blood transfusions and subsequent occurrence of NEC, meta-analyses of randomized controlled trials (RCTs) testing RBC transfusion thresholds or the use of recombinant erythropoiesis-stimulating growth factors did not confirm an association of anemia with ta-NEC. These conflicting data necessitated the development of an animal model to elucidate mechanisms and causal factors. Data from this recent mouse model of ta-NEC highlighted the importance of sequential exposure to severe anemia followed by transfusion for development of ta-NEC.Expert opinion:This review summarizes current human and experimental data, highlights open questions, and suggests avenues for further research aimed at preventing ta-NEC in preterm infants. Further studies are required to delineate whether there is a tipping point, in terms of the level and duration of anemia, and to develop an effective strategy for blood management and the quality of RBC transfusions.

Transfusion thresholds for guiding red blood cell transfusion.

Transfusion thresholds for guiding red blood cell transfusion.

1339 Haemoglobin Threshold for Red Blood Cell Transfusion in Traumatic Brain Injury. A Systematic Review and Meta-Analysis

Abstract Background Traumatic Brain Injury (TBI) is a significant and growing worldwide healthcare burden. Minimising brain hypoxia is important in preventing secondary brain injury. Anaemia is common in TBI patients but there is little evidence as to which haemoglobin (Hb) threshold transfusion should be considered in TBI patients. Objective This present systematic review and meta-analysis of randomised controlled trials aims to assess the effect of high verses low red blood cell transfusion thresholds on functional outcomes and quality of life in TBI patients. Method We searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, and Web of Science up to June 2020. We also searched clinical trial registers, conference proceedings, and reference lists from previous systematic reviews and included studies. We included randomised studies comparing high verses low Hb threshold for red blood cell transfusion in TBI patients. We assessed the following major outcomes: all-cause mortality, transfusion related adverse events and favourable outcome (Glasgow Outcome Scale, GOS). Results We included 3 RCTs involving 311 participants. Our analysis showed no difference in all-cause mortality (3-6 months) (OR 1.17 (95% CI 0.64 to 2.13)) and no difference in GOS (OR 1.10 (95% CI 0.65 to 1.85)) between transfusing red blood cells at 7g/dL or at 9/10g/dL in moderate to severe TBI. Conclusions There is no difference between a high and a low Hb threshold transfusion policy. However, considering the limitations in current evidence there is a need for future high quality randomised controlled trials.

Doctors' practice and attitudes towards red blood cell transfusion at Mthatha Regional Hospital, Eastern Cape, South Africa: A mixed methods study.

BackgroundUnnecessary blood transfusion exposes recipients to potential harms.AimThe aim of this study was to describe blood transfusion practice and explore doctors’ attitudes towards transfusion.SettingA hospital providing level 1 and 2 services.MethodsA mixed-methods study design was used. In the cross-sectional descriptive component, a sample was taken from patients transfused over a 2-month period. Blood use was categorised as for medical anaemia or haemorrhage, and appropriate or not. The qualitative component comprised a purposeful sample for focus group and individual semi-structured interviews.ResultsOf 239 patients sampled, 62% were transfused for medical anaemia and 38% for haemorrhage. In the medical anaemia group, compliance with age-appropriate transfusion thresholds was 69%. In medical anaemia and haemorrhage, 114 (77%) and 85 (93.4%) of recipients had orders for ≥ 2 red blood cell (RBC) units, respectively. In adults ≥ 18 years old with medical anaemia, 47.1% of orders would have resulted in a haemoglobin (Hb) > 8 g/dL. Six doctors participated in focus group and eleven in individual interviews. There was a lack of awareness of institutional transfusion guidelines, disagreement on appropriate RBC transfusion thresholds and comments that more than one RBC unit should always be transfused. Factors informing decisions to transfuse included advice from senior colleagues, relieving symptoms of anaemia and high product costs.ConclusionMost orders were for two or more units. In medical anaemia, doctors’ compliance with RBC transfusion thresholds was reasonable; however, almost half of the orders would have resulted in overtransfusion. The attitudes of doctors sampled suggest that their transfusion practice is influenced more by institutional values than formal guidelines.

Red blood cell transfusion thresholds in extremely low birth weight infants II.

Red blood cell transfusion thresholds in extremely low birth weight infants II.