Red Blood Cell Transfusion Decisions Research Articles

Optimizing RBC Transfusion Outcomes in Patients with Acute Illness and in the Chronic Transfusion Setting

Red blood cell (RBC) transfusion is a common clinical intervention used to treat patients with acute and chronic anemia. The decision to transfuse RBCs in the acute setting is based on several factors but current clinical studies informing optimal RBC transfusion decision making (TDM) are largely based upon hemoglobin (Hb) level. In contrast to transfusion in acute settings, chronic RBC transfusion therapy has several different purposes and is associated with distinct transfusion risks such as iron overload and RBC alloimmunization. Consequently, RBC TDM in the chronic setting requires optimizing the survival of transfused RBCs in order to reduce transfusion exposure over the lifespan of an individual and the associated transfusion complications mentioned. This review summarizes the current medical literature addressing optimal RBC-TDM in the acute and chronic transfusion settings and discusses the current gaps in knowledge which need to be prioritized in future national and international research initiatives.

Clinical implications of using non-invasive haemoglobin monitoring for red blood cell transfusion decision in hip arthroplasty

IntroductionThe decision to transfuse red blood cells requires accurate haemoglobin concentration values. In this study, we evaluated if continuous non-invasive haemoglobin (SpHb) measurement could substitute laboratory determined haemoglobin (LabHb) in patients undergoing elective hip replacement. As secondary objective, we analyzed the trend of the difference between techniques. Materials/methodsLabHb measurements were done using an automated analyser and SpHb measurements were acquired using Radical-7®. In randomly selected patients undergoing hip replacement, whenever blood was collected for LabHb, concomitant SpHb was recorded. Correlation, bias and accuracy of SpHb were calculated in comparison with LabHb. Results108 paired measurements were obtained from 43 patients. The Pearson R of the correlation between SpHb and LabHb was 0.7 (p < 0.001). Bland-Altman test revealed a bias of 1 ± 1.4 g dL−1, meaning Lab Hb was recurrently higher than SpHb. Limits of agreement were [−1.7; 3.8]. Considering RBC transfusion threshold of 8 g dL−1, we found that in two situations transfusion decision would differ based on the measurement considered. Trending ability of SpHb study showed a significant difference between preoperative and postoperative LabHb-SpHb. DiscussionThere was a good correlation between SpHb and LabHb, while bias and limits of agreement were higher than those in literature. There was a limited trending ability of SpHb during the perioperative period. Despite this, using SpHb instead of LabHb for decision making regarding transfusion would only change the decision in 1.9 % of our cases. Our findings suggest that this device could be used as a reference but cannot replace venous puncture as gold standard.

Variation in red cell transfusion practice in the intensive care unit – An international survey

PurposeUnclear recommendations in transfusion guidelines may possibly lead to inconsistency in treatment of patients admitted to the intensive care unit. This study aimed to uncover variation in red blood cell (RBC) transfusion decisions in the ICU worldwide. MethodsMembers of the European Society of Intensive Care Medicine (ESICM) were requested to complete an online questionnaire which included four different hypothetical clinical scenarios. The scenarios represented patients with acute myocardial infarction (AMI), abdominal sepsis, traumatic brain injury (TBI) and post-surgical complications. Hemoglobin level was 7∙3 g/dL in all scenarios. The questionnaire explored the physicians' transfusion decision in each clinical scenario and identified patient characteristics that were most influential in the transfusion decision. ResultsIn total 211 members participated in the study, of whom 142 (67%) completed the entire survey. Most variation was observed in the clinical scenario of sepsis, in which 49% decided to transfuse and 51% decided not to. In the clinical scenarios of AMI, TBI and post-surgical complications this was respectively; 75/25%, 35/65% and 66/34%. ConclusionsCritical care physicians differed in outcome of RBC transfusion decisions and weighed patient characteristics differently. These findings indicate that variation in transfusion practice amongst critical care physicians exists.

Red Cell Alloimmunization Rates in Allogeneic Hematopoietic Stem Cell Transplant Recipients

Introduction: Donor selection for allogeneic hematopoietic stem cell transplant (allo-HSCT) is dependent on matching with the intended recipient HLA allele profile, but not blood group compatibility. Red blood cell (RBC) phenotype matching is not considered, even if recipient alloantibodies are present pre-HSCT. Historically, up to 3.7% of allo-HSCT recipients have been found to develop new RBC alloantibodies following allo-HSCT. We completed an audit of all adult and pediatric allo-HSCT recipients of the Alberta Bone Marrow and Blood Cell Transplant Program to define the rate of RBC alloimmunization, and evaluate the impact of this RBC alloantibody presence on donor marrow engraftment in our allo-HSCT recipient population.Methods:A retrospective review was completed including all allogeneic pediatric and adult HSCT recipients between January 1, 2007 and January 1, 2015. Data was obtained from review of cellular therapy laboratory electronic records with red cell alloantibody information extracted manually from the transfusion medicine laboratory information system.Results: A total of 674 patients, including 104 pediatric recipients (<18 years old), underwent 697 allo-HSCT procedures (591 peripheral blood, 45 marrow, 61 cord blood). The mean HSCT recipient age was 40 (range 0-66) and most common HSCT indication was acute myeloid leukemia. Myeloablative conditioning was given to all adults and 86% of pediatric recipients. Fully HLA matched grafts were provided to 77% of recipients. ABO compatibility status of allo-HSCT procedures included the following: 362 (52%) ABO identical grafts, 154 (22%) grafts with a minor incompatibility, 143 (21%) grafts with a major incompatibility, and 38 (5.0%) grafts with bidirectional incompatibility. Rh mismatches were present in 165 (24%) of donor-recipient pairs.A total of 47 allo-HSCT recipients, including 3 pediatric and 44 adult patients, were found to have RBC alloantibodies before or after allo-HSCT. A total of 45 (6.4%) of allo-HSCT recipients had detectable RBC alloantibodies pre-HSCT, with 69 individual alloantibodies identified. The most common RBC alloantibody was anti-E (30%). Antibody screen results available on the day of or following HSCT in 43 allo-HSCT recipients found: 12 (28%) with antibody disappearance pre-HSCT and a negative screen on the date of allo-HSCT, 15 (35%) with antibody waning to disappearance after allo-HSCT, and 11 (26%) with persistence of pre-HSCT antibodies following allo-HSCT. New post-HSCT RBC alloantibodies were detected in 3 adult recipients of peripheral blood collected stem cell grafts (anti-D; anti-Kpa; anti-K plus anti-E), with an overall rate of 0.4%. These patients all received myeloablative conditioning and grafts which were ABO identical or had a minor ABO incompatibility. The anti-D antibody developed post-transplant in an Rh positive recipient of an Rh negative graft. Thus, the calculated overall rate of anti-D development in Rh mismatched HSCT recipients was 0.6%. There was no observed impact on neutrophil and platelet engraftment comparing adult allo-HSCT recipients who did and did not have pre-HSCT RBC alloantibodies.Conclusion: The risk of post-HSCT RBC alloantibody development is very low, even in Rh mismatched donor-recipient pairs. ABO incompatibility does not affect the risk of post-HSCT alloantibody development. Allo-HSCT recipients infrequently have pre-HSCT RBC alloantibodies, which may disappear after myeloablative conditioning. The presence of RBC alloantibodies pre-HSCT does not appear to impact donor marrow engraftment. The results of our retrospective study are limited by the availability, timing and frequency of post-HSCT antibody screen investigations. The decision to perform an antibody screen post-HSCT is a clinical one, typically dependent on recipient transfusion needs. Further prospective research is required to more accurately determine the rate of new post-HSCT alloantibody development and duration of alloantibody persistence or disappearance in allo-HSCT recipients. Results of these studies may also help guide RBC transfusion decisions in HSCT recipients known to have pre-HSCT RBC alloantibodies with proven engraftment and a negative post-HSCT antibody screen. DisclosuresNo relevant conflicts of interest to declare.

Comportamiento de la hemoglobina en los pacientes críticos: Un análisis de la práctica transfusional en una unidad de cuidados intensivos

IntroductionAnaemia in the critically ill patient is a very common comorbidity. It is of multifactorial origin and is associated with negative outcomes such as prolonged hospital stay and increased mortality. Its value, representing the red cell mass, has been considered the element mostly used in protocols for transfusion decision making. ObjectiveTo describe the haemoglobin levels and analyse transfusion practices in an Intensive Care Unit in Bogota, during a follow up period from July 2008 to December 2014. Materials and methodsThis paper is an observational analytical study with a retrospective cohort design, conducted in an Intensive Care Unit in Bogotá-Colombia. The levels of haemoglobin were analysed using a survival analysis. A tree decision making model was also developed in order to compare transfusion practices with the proposed practices of the available articles on the subject. ResultsThe analysis included a cohort of 4,764 patients, predominantly males (54.58%), with a median age of 65 years (interquartile range: 52-75), and a median length of stay of 6 days (interquartile range: 4-11).There were more non-surgical patients (3,328; 69.86%) than surgical ones (1,436; 30.14%).The initial haemoglobin had a median of 11g/dL (interquartile range: 9.4-12.9), with a significant difference when comparing the surgical group with the non-surgical (P=.005). Haemoglobin was also lower in females, trauma patients, and in post-operative care of major surgery. The event defined as anaemia appears more frequently between the third and fourth day of hospital stay. There was 15.5% mortality. ConclusionAnaemia in the critical care patients is a frequent event, usually observed on the third and fourth day of hospital stay, and mainly in surgical and septic patients. Its relationship to adverse outcomes is yet to be elucidated.The definition of an absolute value as a starting point for red blood cell transfusion decision appears insufficient, according to the available studies and the analysed population. There is a need for prospective studies that take into account confounding variables and benefit/risk ratios, in order to clarify transfusion practices in critically ill patients.

Red blood cell transfusion decision making in critically ill children.

To discuss the tradeoff between permissive anemia and administering red blood cell transfusion to children in pediatric ICUs. Postsurgical mortality in adults increases abruptly if their nadir hemoglobin level falls below 5 g/dl. Patients with sepsis, even those in septic shock, and patients with upper gastrointestinal bleeding do not require red blood cell (RBC) transfusion if their hemoglobin level is above 7 g/dl. Anemia is common in critically ill children and is well tolerated most of the time. RBC transfusion is required in cases of hemorrhagic shock and in children with a hemoglobin level below 5 g/dl. Children with sepsis, including septic shock, those with a severe upper gastrointestinal bleeding and all stable critically ill children, including noncyanotic cardiac children older than 28 days, do not require an RBC transfusion if their hemoglobin level is above 7 g/dl. Transfusion threshold in children with univentricular physiology and in critically ill children with a hemoglobin level between 5 and 7 g/dl remains to be determined.

Red blood cell transfusion: Impact of an education program and a clinical guideline on transfusion practice

Red blood cell (RBC) transfusion guidelines have been developed by professional societies. These guidelines recommend a restrictive RBC transfusion practice for most clinical populations. Despite the consistency of guidelines and limited evidence for RBC transfusion efficacy, there is variability in RBC transfusion practice. A program was initiated in a tertiary medical center to align RBC transfusion practice with best-practice RBC transfusion guidelines. The program included an educational program, followed after 6 months by RBC transfusion decision support that included the approval of a best-practice RBC transfusion guideline by the hospital medical board and an RBC transfusion order form that included the guideline recommendations. RBC transfusion practice was followed over an 18-month period and compared with transfusion practice over the prior 18 months. The primary outcome variables were adult inpatient RBC units transfused, RBC units per admission, and RBC units per 100 patient-days. The mean RBC units transfused decreased with initiation of each component of the program: from 923 ± 68 units to 852 ± 40 (P = 0.025) with education and further to 690 ± 52 (P < 0.0001) with the RBC transfusion decision support. Similarly, RBC transfusions per 100 patient-days fell from 10.56 ± 0.80 to 9.69 ± 0.49 (P = 0.02) and to 7.68 ± 0.63 (P = 0.0001) during the 3 time periods. An education program coupled with institutional adoption of a best-practice RBC transfusion guideline and RBC transfusion order set resulted in a reduction in total RBC units transfused.

Red Cell Transfusion Practice in Patients Presenting With Acute Upper Gastrointestinal Bleeding- A Survey of 815 Clinicians

Introduction Acute Upper Gastrointestinal Bleeding (AUGIB) accounts for 14% of all red blood cell (RBC) transfusions in England. Studies of RBC transfusion practice in critical care and cardiac surgery have shown widespread practice variation. Since there are no such data in AUGIB and, as a consequence of recent evidence that early transfusion is associated with adverse outcomes in AUGIB,1 the current study was designed to assess attitudes towards RBC transfusion practice in patients presenting with AUGIB. Methods A survey depicting six vignettes representing a range of clinical scenarios in AUGIB were piloted for content and emailed to practicing consultants and registrars in gastroenterology, acute medicine and upper gastrointestinal surgery through their member organisations. Respondents were asked to select a haemoglobin (Hb) trigger at which they would ordinarily transfuse red blood cells. Results were analysed using proportional odds models and robust standard errors were used to account for clustering. Results The overall response rate was 48% (815/1709). Transfusion triggers differed significantly between all six scenarios (p 9g/dl was chosen by only 13.3% of respondents to scenario 2 (young patient with features of shock). In comparison, a Hb trigger of >9 g/dl was chosen for 45.2% of respondents in scenario 4 representing an older patient with ischemic heart disease. 10 g/dl in all scenarios. The selected Hb trigger differed between clinical specialities. Surgeons selected a lower Hb transfusion trigger than physicians across all 6 scenarios ( p p 5 years). Only 70% of respondents reported familiarity with national guidelines for AUGIB. Most clinicians favoured a restrictive approach to transfusion, which is in part discordant with actual transfusion practice observed in the UK National Audit of AUGIB, where 15% of all early RBC transfusions were administered to patients with a Hb >10g/dL (38% of whom were haemodynamically stable) and to 50% of admissions with a presenting Hb 8.1–10 g/dl and haemodynamic stability. Conclusion There is widespread variation in attitudes towards RBC transfusion for AUGIB. Both clinician and patient characteristics influence RBC transfusion decisions. Clinical studies are needed to evaluate the safety and efficacy of differing blood transfusion strategies in AUGIB.

* Red cell transfusion practice in patients presenting with acute upper gastrointestinal bleeding- a survey of 815 clinicians

IntroductionAcute Upper Gastrointestinal Bleeding (AUGIB) accounts for 14% of all red blood cell (RBC) transfusions in England. Studies of RBC transfusion practice in critical care and cardiac surgery have shown...

Hematocrit correlates well with circulating red blood cell volume in very low birth weight infants.

Although circulating red blood cell (RBC) volume is a better measure of total body oxygen delivering capacity than hematocrit (HCT), circulating RBC volume is more difficult to measure. Thus, the HCT is often used in RBC transfusion decisions. However, several previous studies of low birth weight infants have reported that the correlation between HCT and circulating RBC volume is poor. Using a robust nonradioactive method based on in vivo dilution of biotinylated RBC enumerated by flow cytometry, the present study reexamined the correlation between HCT and circulating RBC volume in very low birth weight infants. Venous and capillary HCT levels were compared with circulating RBC volume measured using the biotin method. Twenty-six stable very low birth weight infants with birth weights less than 1300 g were studied on 43 occasions between 7 and 79 d of life. Venous HCT values correlated highly with circulating RBC volume (r = 0.907; p < 0.0001). However, the mean 95% confidence limits for prediction of circulating RBC volume from venous HCT (the average error of prediction) was +/-13.4 mL/kg. The correlation between HCT and circulating RBC volume is strong in older stable very low birth weight infants. However, clinically important uncertainty exists in estimating circulating RBC volume and the associated RBC transfusion needs of an individual infant based on venous HCT. Because direct measurement of circulating RBC volume is not yet practical, the HCT (or the blood Hb concentration) remains the best available indirect indicator.

A physiologic basis for red blood cell transfusion decisions

Identification of a universal “transfusion trigger” has eluded surgeons for years. Optimization of cardiopulmonary hemodynamics should precede the decision to transfuse red blood cells. Red blood cell transfusion should be considered when global oxygen delivery falls below a critical point with increasing oxygen extraction and lactate levels. At present, these parameters must be monitored with invasive techniques. This article addresses some aspects of global oxygen delivery physiology that appear to correlate with cardiac function, metabolism, and tissue perfusion.