Determinants of hospital variability in perioperative red blood cell transfusions during coronary artery bypass graft surgery.

OBJECTIVE: To identify to what extent distinguishing patient and procedural characteristics can explain center-level transfusion variation during coronary artery bypass grafting surgery. METHODS: Observational cohort study using the Perfusion Measures and Outcomes Registry from 43 adult cardiac surgical programs from July 1, 2011, to July 1, 2017. Iterative multilevel logistic regression models were constructed using patient demographic characteristics, preoperative risk factors, and intraoperative conservation strategies to progressively explain center-level transfusion variation. RESULTS: Of the 22,272 adult patients undergoing isolated coronary artery bypass surgery using cardiopulmonary bypass, 7241 (32.5%) received at least 1 U allogeneic red blood cells (range, 10.9%-59.9%). When compared with patients who were not transfused, patients who received at least 1 U red blood cells were older (68 vs 64 years; P < .001), were women (41.5% vs 15.9%; P < .001), and had a lower body surface area (1.93 m2 vs 2.07 m2; P < .001), respectively. Among the models explaining center-level transfusion variability, the intraclass correlation coefficients were 0.07 for model 1 (random intercepts), 0.12 for model 2 (patient factors), 0.14 for model 3 (intraoperative factors), and 0.11 for model 4 (combined). The coefficient of variation for center-level transfusion rates were 0.31, 0.29, 0.40, and 0.30 for models 1 through 4, respectively. The majority of center-level variation could not be explained through models containing both patient and intraoperative factors. CONCLUSIONS: The results suggest that variation in center-level red blood cells transfusion cannot be explained by patient and procedural factors alone. Investigating organizational culture and programmatic infrastructure may be necessary to better understand variation in transfusion practices.

Development and Validation of a Nomogram for Predicting Albumin Transfusion After Spinal Tuberculosis Surgery: Based on Propensity Score Matching Analysis.

BACKGROUND: There have been few literature reports on the use of perioperative parameters to predict the risk of albumin transfusion after spinal tuberculosis surgery based on the application of nomogram and propensity score matching (PSM) analysis. OBJECTIVE: The purpose was to predict the risk of albumin transfusion after spinal tuberculosis surgery based on a combination of PSM and nomogram. METHODS: The clinical data of the patients were collected in our hospital, including preoperative clinical data, preoperative laboratory tests, and postoperative clinical data. All data were divided into 2 groups, including the albumin transfusion group and the non-albumin transfusion group. The PSM analysis was used to adjust the baseline data of the 2 groups. The nomogram was further constructed. The practicability and predictive ability of the model were evaluated. RESULTS: A total of 494 cases were collected in this article; 102 pairs by PSM analysis were used to construct the nomogram. There were statistical differences in surgical approach, aspartate aminotransferase/alanine aminotransferase levels, drainage, and kyphosis by logistic analysis, and these parameters were included in the construction of the nomogram. The C-index of the prediction model was 0.734. The area under the curve was 0.73 and the net benefit was between 0.13 and 0.99. The calculated C-index was 0.71 by the internal verification method. CONCLUSIONS: The PSM analysis had a good matching effect and the nomogram had a good predictive ability. Surgical approach, aspartate aminotransferase/alanine aminotransferase levels, drainage, and kyphosis might be predictors of albumin transfusion after spinal tuberculosis surgery.

Prolonged Blood Storage and Risk of Posttransfusion Acute Kidney Injury.

BACKGROUND: Erythrocyte transfusions are independently associated with acute kidney injury. Kidney injury may be consequent to the progressive hematologic changes that develop during storage. This study therefore tested the hypothesis that prolonged erythrocyte storage increases posttransfusion acute kidney injury. METHODS: The Informing Fresh versus Old Red Cell Management (INFORM) trial randomized 31,497 patients to receive either the freshest or oldest available matching erythrocyte units and showed comparable mortality with both. This a priori substudy compared the incidence of posttransfusion acute kidney injury in the randomized groups. Acute kidney injury was defined by the creatinine component of the Kidney Disease: Improving Global Outcomes criteria. RESULTS: The 14,461 patients included in this substudy received 40,077 erythrocyte units. For patients who received more than one unit, the mean age of the blood units was used as the exposure. The median of the mean age of blood units transfused per patient was 11 days [interquartile range, 8, 15] in the freshest available blood group and 23 days [interquartile range, 17, 30] in the oldest available blood group. In the primary analysis, posttransfusion acute kidney injury was observed in 688 of 4,777 (14.4%) patients given the freshest available blood and 1,487 of 9,684 (15.4%) patients given the oldest available blood, with an estimated relative risk (95% CI) of 0.94 (0.86 to 1.02; P = 0.132). The secondary analysis treated blood age as a continuous variable (defined as duration of storage in days), with an estimated relative risk (95% CI) of 1.00 (0.96 to 1.04; P = 0.978) for a 10-day increase in the mean age of erythrocyte units. CONCLUSIONS: In a population of patients without severely impaired baseline renal function receiving fewer than 10 erythrocyte units, duration of blood storage had no effect on the incidence of posttransfusion acute kidney injury.

Hematological Biomarkers, Mortality, Transfusion and Acute Heart Disease.

BACKGROUND: Patients hospitalized with acute heart disease [acute myocardial infarction (MI); heart disease exacerbation] may require red blood cell (RBC) transfusion. These patients are at increased risk for morbidity and mortality. Hematological biomarkers may help to identify increased mortality risk. The aim of the study was to evaluate the association between hematological biomarkers and survival in these patients. METHODS: A historical cohort study of all patients admitted to an internal medicine department, who were diagnosed with acute heart disease and requiring RBC transfusion, was carried out in a tertiary medical center between 2009-2014. The association between hematological biomarkers and 30-, 90-day and 5-year mortality was studied. RESULTS: A total of 254 patients (median age 80 years, IQR 74-86.25; 40.9% females; acute MI 24.8%), were included. During the 5-year follow-up 212(83.5%) patients died. In a multivariate analysis the lower platelet to neutrophil ratio (PNR) was significantly associated with increased 30-, 90-day and 5-year mortality (p<0.001, 0.041, 0.003 respectively). A higher red cell distribution width (RDW) was significantly associated with 30- and 90-day mortality (p=0.003, 0.023 respectively), while higher neutrophil to lymphocyte ratio (NLR) was associated with increased 30-day and 5-year mortality (p= 0.036, 0.033 respectively). CONCLUSIONS: Hematological biomarkers may help to identify increased mortality risk of acute heart disease patients, receiving RBC transfusions in an internal medicine department.

Hematocrit as a predictor of preoperative transfusion-associated complications in spine surgery: A NSQIP study.

BACKGROUND CONTEXT: Preoperative optimization of medical comorbidities prior to spinal surgery is becoming an increasingly important intervention in decreasing postoperative complications and ensuring a satisfactory postoperative course. The treatment of preoperative anemia is based on guidelines made by the American College of Cardiology (ACC), which recommends packed red blood cell transfusion when hematocrit is less than 21% in patients without cardiovascular disease and 24% in patients with cardiovascular disease. The literature has yet to quantify the risk profile associated with preoperative pRBC transfusion. PURPOSE: To determine the incidence of complications following preoperative pRBC transfusion in a cohort of patients undergoing spine surgery. STUDY DESIGN: Retrospective review of a national surgical database. PATIENT SAMPLE: The national surgical quality improvement program database OUTCOME NEASURES: Postoperative physiologic complications after a preoperative transfusion. Complications were defined as the occurrence of any DVT, PE, stroke, cardiac arrest, myocardial infarction, longer length of stay, need for mechanical ventilation greater than 48 h, surgical site infections, sepsis, urinary tract infections, pneumonia, or higher 30-day mortality. METHODS: The national surgical quality improvement program database was queried, and patients were included if they had any type of spine surgery and had a preoperative transfusion. RESULTS: Preoperative pRBC transfusion was found to be protective against complications when the hematocrit was less than 20% and associated with more complications when the hematocrit was higher than 20%. In patients with a hematocrit higher than 20%, pRBC transfusion was associated with longer lengths of stay, and higher rates of ventilator dependency greater than 48 h, pneumonia, and 30-day mortality. CONCLUSION: This is the first study to identify an inflection point in determining when a preoperative pRBC transfusion may be protective or may contribute to complications. Further studies are needed to be conducted to stratify by the prevalence of cardiovascular disease.

Transfusion in critical care: Past, present and future.

Anaemia and coagulopathy are common in critically ill patients and are associated with poor outcomes, including increased risk of mortality, myocardial infarction, failure to be liberated from mechanical ventilation and poor physical recovery. Transfusion of blood and blood products remains the corner stone of anaemia and coagulopathy treatment in critical care. However, determining when the benefits of transfusion outweigh the risks of anaemia may be challenging in some critically ill patients. Therefore, the European Society of Intensive Care Medicine prioritised the development of a clinical practice guideline to address anaemia and coagulopathy in non-bleeding critically ill patients. The aims of this article are to: (1) review the evolution of transfusion practice in critical care and the direction for future developments in this important area of transfusion medicine and (2) to provide a brief synopsis of the guideline development process and recommendations in a format designed for busy clinicians and blood bank staff. These clinical practice guidelines provide recommendations to clinicians on how best to manage non-bleeding critically ill patients at the bedside. More research is needed on alternative transfusion targets, use of transfusions in special populations (e.g., acute neurological injury, acute coronary syndromes), use of anaemia prevention strategies and point-of-care interventions to guide transfusion strategies.

Do Antifibrinolytic Agents Reduce the Risk of Blood Transfusion in Children Undergoing Spinal Fusion?: A Propensity Score-matched Comparison Using a National Database.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To evaluate the effectiveness and safety of antifibrinolytic (AF) agents in reducing perioperative blood transfusion in pediatric patients undergoing spinal fusion. SUMMARY OF BACKGROUND DATA: The potential for AF to decrease bleeding and reduce exposure to allogenic transfusions has led to widespread off-label use in a number of major pediatric surgical procedures. Recent reviews call for improving the body of evidence for their effectiveness and safety in pediatric spinal fusion. METHODS: Children undergoing spinal fusion were identified in the American College of Surgeons National Surgical Quality Improvement Program Pediatric (NSQIP-P) 2016 and 2017 databases. Univariate analyses of patient and perioperative characteristics informed the creation of a propensity score model predicting treatment with AF, followed by 1:1 matching to allow comparison of allogenic red blood cell transfusion rates and secondary outcomes between treated and untreated patients. RESULTS: Of 6626 total patients, 5434 (81%) received AF and 1533 (23%) received a blood transfusion. Analysis of data for 1192 propensity score-matched pairs revealed that treatment with AF was associated with a statistically nonsignificant 16% reduction in perioperative transfusion (OR 0.84, 95% confidence interval 0.68-1.05, P = 0.119) and a statistically significant 43% reduction in postoperative transfusion (OR 0.57, 95% confidence interval 0.39-0.81, P = 0.002). No differences in the incidences of postoperative seizure or thrombosis were observed, with overall rates of 7.5 and 22.5 events per 10,000 patients, respectively. CONCLUSION: AF agents appear to reduce postoperative allogenic transfusion in children undergoing spinal fusion surgery. Adverse drug effects such as thromboembolic complications and seizure were extremely rare and warrant continued monitoring, though this is the largest study to date providing evidence for the safety profile of these drugs. LEVEL OF EVIDENCE: 3.

Alloimmunization and autoimmunization in adult transfusion-dependent thalassemia patients: a report from a comprehensive center in Israel.

Patients with beta thalassemia major (TM) are transfusion-dependent (TD) since early childhood and for life. Development of alloantibodies and autoantibodies against red blood cell (RBC) antigens is increasingly recognized as a significant transfusion hazard, especially among heavily transfused patients. The aim of this study is to assess RBC alloimmunization and autoimmunization rates in TD TM patients treated in our Comprehensive Center of Adult Thalassemia, Hemoglobinopathies and Rare Anemias. TD TM patients, regularly transfused every 2-3 weeks, were included in the study. Clinical and RBC transfusion records, including RBC antibodies, since diagnosis in early childhood, were retrieved from patients' files and from the blood bank database. Forty TD TM patients, > 18 years of age, were included in the study. Alloimmunization was demonstrated in 17 (42.5%) patients. Thirty-four alloantibodies were detected, with the most frequent being RH related (12 of 34, 35.3%) followed by those of the Kell system (8 of 34, 23.5%). Age at first transfusion was positively related to the probability of developing alloantibodies (p = 0.02). Splenectomy was found to be correlated with developing alloantibodies (p = 0.016). Logistic regression analysis of the lifelong probability of developing alloantibodies on the age at first transfusion and splenectomy demonstrates a strong positive relationship (p = 0.002). A substantially high rate of alloimmunization was found among adult TD TM patients. Early initiation of RBC transfusions, avoidance of splenectomy and extended Rh and K antigen matching, can reduce the incidence of alloimmunization in TD TM patients.

Evolution of perioperative blood transfusion practice after coronary artery bypass grafting in the past two decades.

BACKGROUND AND AIM OF THE STUDY: Transfusion of blood products after coronary artery bypass grafting (CABG) is associated with increased morbidity and mortality. We evaluated the perioperative use of blood products in patients undergoing CABG in our institution over the past two decades. METHODS: The study included 18 992 patients who underwent isolated CABG at our hospital between 1998 and 2017. Baseline characteristics of patients and the number of perioperative transfusions during their hospital stay (including red blood cells [RBCs], platelets, and fresh frozen plasma [FFP]) were assessed. Logistic regression models were used to identify risk factors for perioperative transfusion. RESULTS: The rates of perioperative RBC transfusion decreased for all patients undergoing isolated CABG (52.1% in 1998 vs 18.6% in 2017) in our institution. The mean number of transfused RBC units was significantly higher in women than in men (1.57 ± 2.2 vs 0.68 ± 1.84; P < .005); this difference remained significant over the years. After adjusting the results for other risk factors, female sex was a significant independent risk factor for perioperative RBC transfusion. The platelet transfusion rate increased over the past two decades (1.4% in 1998 vs 9.7% in 2017). The number of FFP transfusions remained unchanged. CONCLUSIONS: Over the past two decades, we observed a decrease in the incidence of perioperative RBC transfusions in patients undergoing isolated CABG, whereas platelet transfusions increased. Female sex was an independent predictor of perioperative RBC transfusion.

Red blood cell consumption in a large cohort of patients with thalassaemia: a retrospective analysis of main predictors.

The phenotype/genotype relationship of patients with transfusion-dependent thalassaemia (TDT) is particularly complex and variable, thus generating different levels of severity and of annual transfusion volume (ATV). In this study, we explored the role and the contribution of several factors potentially involved in determining mean ATV in a cohort of TDT patients which have been followed since long time. We collected data on one-hundred and twenty-seven patients with transfusion-dependent ß-thalassaemia followed at Rare Blood Cell Disease Unit, AORN Cardarelli Hospital. Age at first transfusion, genotype, spleen status (splenectomy or not), and mean soluble transferrin receptor (sTfR) were the parameters included in the analysis. At stepwise regression analysis which included all the parameters, only splenectomy and mean sTfR significantly predicted the mean ATV (F = 70.94, P < 0.0001, R2 = 0.540). Overall, our data may suggest that in patients with TDT, the measurement of sTfR level together with the spleen status could contribute, more accurately than genotype, to provide a basal evaluation of residual erythropoietic activity and mean ATV.

Using arterial-venous oxygen difference to guide red blood cell transfusion strategy.

BACKGROUND: Guidelines recommend a restrictive red blood cell transfusion strategy based on hemoglobin (Hb) concentrations in critically ill patients. We hypothesized that the arterial-venous oxygen difference (A-V O2diff), a surrogate for the oxygen delivery to consumption ratio, could provide a more personalized approach to identify patients who may benefit from transfusion. METHODS: A prospective observational study including 177 non-bleeding adult patients with a Hb concentration of 7.0-10.0 g/dL within 72 h after ICU admission. The A-V O2diff, central venous oxygen saturation (ScvO2), and oxygen extraction ratio (O2ER) were noted when a patient's Hb was first within this range. Transfusion decisions were made by the treating physician according to institutional policy. We used the median A-V O2diff value in the study cohort (3.7 mL) to classify the transfusion strategy in each patient as "appropriate" (patient transfused when the A-V O2diff > 3.7 mL or not transfused when the A-V O2diff ≤ 3.7 mL) or "inappropriate" (patient transfused when the A-V O2diff ≤ 3.7 mL or not transfused when the A-V O2diff > 3.7 mL). The primary outcome was 90-day mortality. RESULTS: Patients managed with an "appropriate" strategy had lower mortality rates (23/96 [24%] vs. 36/81 [44%]; p = 0.004), and an "appropriate" strategy was independently associated with reduced mortality (hazard ratio [HR] 0.51 [95% CI 0.30-0.89], p = 0.01). There was a trend to less acute kidney injury with the "appropriate" than with the "inappropriate" strategy (13% vs. 26%, p = 0.06), and the Sequential Organ Failure Assessment (SOFA) score decreased more rapidly (p = 0.01). The A-V O2diff, but not the ScvO2, predicted 90-day mortality in transfused (AUROC = 0.656) and non-transfused (AUROC = 0.630) patients with moderate accuracy. Using the ROC curve analysis, the best A-V O2diff cutoffs for predicting mortality were 3.6 mL in transfused and 3.5 mL in non-transfused patients. CONCLUSIONS: In anemic, non-bleeding critically ill patients, transfusion may be associated with lower 90-day mortality and morbidity in patients with higher A-V O2diff. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03767127. Retrospectively registered on 6 December 2018.

Designing and implementing an all Wales postpartum haemorrhage quality improvement project: OBS Cymru (the Obstetric Bleeding Strategy for Wales).

BACKGROUND: Postpartum haemorrhage (PPH) contributes to substantial maternal morbidity. Research into PPH has led to improvements in care which have been incorporated into the Obstetric Bleeding Strategy for Wales. INTERVENTION: A national quality improvement team supported local teams in implementing multiple interventions including risk assessment, objective measurement of blood loss, multiprofessional assessment (at the bedside at 1000 mL blood loss) and point-of-care (POC) testing of coagulation to guide blood product resuscitation during PPH. The project was rolled out to all 12 obstetric units in 2017. The interventions were reinforced by an All Wales Guideline, PPH proforma and standardised training. A national database, biannual audits, and patient and staff surveys reported process and outcome measures. RESULTS: Process measures: during 2017, there was an increase in the percentage of maternities with documented risk assessment (0%-76%), objective measurement of blood loss (52%-88%) and POC testing for coagulation for PPH ≥1500 mL (38%-59%). Maternity staff survey indicated that 94% were aware of the project and 87% stated that it had changed their unit's management of PPH. Interim outcome measures: the incidence (95% CI) of PPH ≥2500 mL per 1000 maternities in 2017 was 6.03 (5.23-6.95). The annual number of women receiving any red blood cell transfusion, level 3 intensive care admission and hysterectomy for PPH was 19.7 (18.2 to 21.3), 0.702 (0.464 to 1.06) and 0.255 (0.129 to 0.504) per 1000 maternities, respectively. CONCLUSIONS: A high level of project awareness across Welsh maternity units has been achieved. Measurement of blood loss was reported to be the most important early change in practice, while PPH documentation and POC testing continue to be embedded. Combining qualitative and quantitative measures to inform implementation has improved project delivery and allowed teams to adapt to local contexts.

Sublingual microcirculation does not reflect red blood cell transfusion thresholds in the intensive care unit-a prospective observational study in the intensive care unit.

PURPOSE: Hemoglobin (Hb) transfusion thresholds are established in intensive care units. A restrictive transfusion threshold (Hb 70-75 g/l) is recommended in septic patients, and a liberal transfusion threshold (Hb 90 g/l) for cardiogenic shock. It is unclear whether these historically adopted transfusion thresholds meet the challenges of individual patients. METHODS: We evaluated microvascular flow index (MFI) and proportion of perfused vessels (PPV) in the sublingual microcirculation with CytoCam-IDF microscopy and near-infrared spectroscopy (NIRS). A study team-independent, treating intensivist assigned a total of 64 patients to 1 of 2 two transfusion thresholds, 43 patients to the Hb 75 g/l threshold and 21 patients to the Hb 90 g/l threshold, at a surgical intensive care unit. We performed microcirculatory measurements 1 h before and 1 h after transfusion of 1 unit of red blood cells. RESULTS: Microcirculatory flow variables correlated negatively with pre-transfusion flow variables (ΔMFI: ρ = - 0.821, p <  0.001; ΔPPV: ρ = - 0.778, p <  0.001). Patients with good initial microcirculation (cutoffs: MFI > 2.84, PPV > 88%) showed a deteriorated microcirculation after red blood cell transfusion. An impaired microcirculation improved after transfusion. At both transfusion thresholds, approximately one third of the patients showed an initially impaired microcirculation. In contrast, one third in every group had good microcirculation above the cutoff variables and did not profit from the transfusion. CONCLUSION: The data suggest that the established transfusion thresholds and other hemodynamic variables do not reflect microcirculatory perfusion of patients. Blood transfusion at both thresholds 75 g/l and 90 g/l hemoglobin can either improve or harm the microcirculatory blood flow, questioning the concept of arbitrary transfusion thresholds.

Red blood cell transfusions for emergency department patients with gastrointestinal bleeding within an integrated health system.

STUDY OBJECTIVE: To assess trends over time in red blood cell (RBC) transfusion practice among emergency department (ED) patients with gastrointestinal (GI) bleeding within an integrated healthcare system, inclusive of 21 EDs. METHODS: Retrospective cohort of ED patients diagnosed with GI bleeding between July 1st, 2012 and September 30th, 2016. The primary outcome was receipt of an RBC transfusion in the ED. Secondary outcomes included 90-day rates of RBC transfusion, repeat ED visits, rehospitalization, and all-cause mortality. Logistic regression was used to obtain confounder-adjusted outcome rates. RESULTS: A total of 24,868 unique patient encounters were used for the primary analysis. The median hemoglobin level in the ED prior to RBC transfusion decreased from 7.5 g/dl to 6.9 g/dl in the first versus last twelve months of the study period (p < 0.0001). A small trend was observed in the overall adjusted rate of ED RBC transfusion (absolute quarterly change of -0.1%, R2 = 0.18, p = 0.0001) largely attributable to the subgroup of patients with hemoglobin nadirs between 7.0 and 9.9 g/dl (absolute quarterly change of -0.4%, R2 = 0.38, p < 0.0001). Rates of RBC transfusions through 90 days likewise decreased (absolute quarterly change of -0.4%, R2 = 0.85, p < 0.0001) with stable to decreased corresponding rates of repeat ED visits, rehospitalizations and mortality. CONCLUSION: Rates of ED RBC transfusion decreased over time among patients with GI bleeding, particularly in those with hemoglobin nadirs between 7.0 and 9.9 g/dl. These findings suggest that ED providers are willing to adopt evidence-based restrictive RBC transfusion recommendations for patients with GI bleeding.

Transfusion Medicine Equations Made Internet Accessible.

Multiple mathematical equations inform the practice of transfusion medicine. These equations apply to a wide range of topics: dosage of blood products, calculation of fluid volumes, and even specific treatment decisions (e.g. corrected count increment for determination of platelet refractoriness). The calculation of these equations can be complicated, prone to error, and time-consuming. A trusted source is needed to accurately perform these calculations 24 hours a day without error and without monetary cost. We sought to build internet-enabled calculators relevant to the practice of transfusion medicine. We partnered with MDCalc, an online host of medical calculators with 1 million monthly users in 196 countries, to design and host the calculators. The calculators guide users in the application of transfusion medicine equations by providing indications for use, inputs for the equations variables, error-checking, warnings for bad inputs, and interpretive guidance of the result. The following calculators were built: blood volume, corrected count increment (CCI), plasma dosage, cryoprecipitated antihemophilic factor dosage, approximate number of units for compatibility testing, maternal-fetal hemorrhage Rh(D) immune globulin dosage, intrauterine RBC transfusion dosage, neonatal polycythemia partial exchange, theoretical removal of a substance by plasmapheresis, sickle cell RBC exchange volume, peripheral blood stem cell collection, and a calculator relevant to donor lymphocyte infusion. Clinicians can now utilize this reputable and highly visible online source to access these common transfusion medicine equations at any time with an internet-enabled device (https://www.mdcalc.com/search?filter=transfusion+medicine).

Past, present, and future: a qualitative and literature study identifying historical trends, drivers, and transformational factors for the future demand of blood supply in the Netherlands.

BACKGROUND: As blood transfusion has evolved, there is a need to understand its historical trends and underlying drivers. Furthermore, for blood bank management to make decisions about the future, they need to consider what transformational factors (defined as developments in science, society, and technology) could significantly impact blood demand and to what effect. This study has a two-fold aim: to explore transfusion experts' perspectives regarding 1) historical trends and drivers of red blood cells (RBCs) in the past 20 years and 2) transformational factors that would impact the future demand of RBCs and to what effect. STUDY DESIGN AND METHODS: Forty-two semi-structured interviews were held with transfusion experts from the Netherlands and abroad, supplemented with a literature review of Pubmed, Google Scholar, and gray literature. RESULTS: With regard to historical trends and drivers, experts shared two main trends: decreased or increased demands for RBCs. Various drivers were reported for each trend, coupled with evidence from literature. With regard to the future, experts anticipated that RBC demands will either increase (17%), decrease (45%), decrease but stabilize (12%), or stabilize as is (7%). Various transformational factors were found to support each trend (e.g., gene therapy will reduce RBC demand), although there were factors for which experts were unsure about its effects (e.g., cultured RBCs). Seven groups of transformation factors were identified in the literature review. CONCLUSION: While the future of blood transfusion is uncertain, there are actions that blood banks may take now to prepare for potential future developments.

Initial Postoperative Hemoglobin Values and Clinical Outcomes in Transfused Patients Undergoing Noncardiac Surgery.

BACKGROUND: Intraoperative red blood cell (RBC) transfusion is common, yet transfusion strategies remain controversial as pretransfusion hemoglobin triggers are difficult to utilize during acute bleeding. Alternatively, postoperative hemoglobin values may provide useful information regarding transfusion practices, though optimal targets remain undefined. METHODS: This is a single-center observational cohort study of adults receiving allogeneic RBCs during noncardiac surgery from 2010 through 2014. Multivariable regression analyses adjusting for patient illness, laboratory derangements, and surgical features were used to assess relationships between initial postoperative hemoglobin values and a primary outcome of hospital-free days. RESULTS: A total of 8060 patients were included. Those with initial postoperative hemoglobin <7.5 or ≥11.5 g/dL had decreased hospital-free days [mean (95% confidence interval [CI]), -1.45 (-2.50 to -0.41) and -0.83 (-1.42 to -0.24), respectively] compared to a reference range of 9.5-10.4 g/dL (overall P value .003). For those with hemoglobin <7.5 g/dL, the odds (95% CI) for secondary outcomes included acute kidney injury (AKI) 1.43 (1.03-1.99), mortality 2.10 (1.18-3.74), and cerebral ischemia 3.12 (1.08-9.01). The odds for postoperative mechanical ventilation with hemoglobin ≥11.5 g/dL were 1.33 (1.07-1.65). Secondary outcome associations were not significant after multiple comparisons adjustment (Bonferroni P < .0056). CONCLUSIONS: In transfused patients, postoperative hemoglobin values between 7.5 and 11.5 g/dL were associated with superior outcomes compared to more extreme values. This range may represent a target for intraoperative transfusions, particularly during active bleeding when pretransfusion hemoglobin thresholds may be impractical or inaccurate. Given similar outcomes within this range, targeting hemoglobin at the lower aspect may be preferable, though prospective validation is warranted.

Packed red blood cell transfusion associates with acute kidney injury after transcatheter aortic valve replacement.

BACKGROUND: Acute kidney injury after cardiac surgery significantly associates with morbidity and mortality. Despite not requiring cardiopulmonary bypass, transcatheter aortic valve replacement patients have an incidence of post-procedural acute kidney injury similar to patients who undergo open surgical aortic valve replacement. Packed red blood cell transfusion has been associated with morbidity and mortality after cardiac surgery. We hypothesized that packed red blood cell transfusion independently associates with acute kidney injury after transcatheter aortic valve replacement, after accounting for other risk factors. METHODS: This is a single-center retrospective cohort study of 116 patients undergoing transcatheter aortic valve replacement. Post-transcatheter aortic valve replacement acute kidney injury was defined by Kidney Disease: Improving Global Outcomes serum creatinine-based criteria. Univariate comparisons between patients with and without post-transcatheter aortic valve replacement acute kidney injury were made for clinical characteristics. Multivariable logistic regression was used to assess independent association of packed red blood cell transfusion with post-transcatheter aortic valve replacement acute kidney injury (adjusting for pre-procedural renal function and other important clinical parameters). RESULTS: Acute kidney injury occurred in 20 (17.2%) subjects. Total number of packed red blood cells transfused independently associated with post-procedure acute kidney injury (OR = 1.67 per unit, 95% CI 1.13-2.47, P = 0.01) after adjusting for pre-procedure estimated glomerular filtration rate (OR = 0.97 per ml/min/1.73m2, 95% CI 0.94-1.00, P = 0.05), nadir hemoglobin (OR = 0.88 per g/dL increase, CI 0.61-1.27, P = 0.50), and post-procedure maximum number of concurrent inotropes and vasopressors (OR = 2.09 per inotrope or vasopressor, 95% CI 1.19-3.67, P = 0.01). CONCLUSION: Packed red blood cell transfusion, along with post-procedure use of inotropes and vasopressors, independently associate with acute kidney injury after transcatheter aortic valve replacement. Further studies are needed to elucidate the pathobiology underlying these associations.

What Is New about Transfusions for Preterm Infants? An Update.

Currently the question of whether to maintain a higher hemoglobin level by transfusing more liberally, as opposed to a more restrictive strategy with lower hemoglobin maintenance levels, has not been answered. We review summarized conclusions of a Cochrane systematic review and meta-analysis of 614 infants in 4 randomized controlled trials (RCT) pooling data. This suggests potential benefits of higher hemoglobin levels, i.e., a possible improved cognition of infants at 18-21 months' corrected age and a reduction of apnea. However, the data on cognition is hypothesis generating as it derives from a post hoc analysis from a single trial in 451 infants. Moreover, the data on apnea need confirmation in larger trials. The effect of adding data of cognitive 2-year outcomes of 1,744 infants from 2 RCT, which will be reported soon, should expand our understanding. This new data will need to be integrated with the older generation of RCTs but also with emerging suggestions from observational data on potential risks of blood transfusions. We discuss some of these warnings from observational studies. Finally, we ask whether we are ready to individualize blood transfusion to physiological measures made in individual infants, and we point to some current difficulties hindering this step.