Supplemental findings of the 2019 National Blood Collection and Utilization Survey.

INTRODUCTION: Supplemental data from the 2019 National Blood Collection and Utilization Survey (NBCUS) are presented and include findings on donor characteristics, autologous and directed donations and transfusions, platelets (PLTs), plasma and granulocyte transfusions, pediatric transfusions, transfusion-associated adverse events, cost of blood units, hospital policies and practices, and implementation of blood safety measures, including pathogen reduction technology (PRT). METHODS: National estimates were produced using weighting and imputation methods for a number of donors, donations, donor deferrals, autologous and directed donations and transfusions, PLT and plasma collections and transfusions, a number of crossmatch procedures, a number of units irradiated and leukoreduced, pediatric transfusions, and transfusion-associated adverse events. RESULTS: Between 2017 and 2019, there was a slight decrease in successful donations by 1.1%. Donations by persons aged 16-18 decreased by 10.1% while donations among donors >65 years increased by 10.5%. From 2017 to 2019, the median price paid for blood components by hospitals for leukoreduced red blood cell units, leukoreduced apheresis PLT units, and for fresh frozen plasma units continued to decrease. The rate of life-threatening transfusion-related adverse reactions continued to decrease. Most whole blood/red blood cell units (97%) and PLT units (97%) were leukoreduced. CONCLUSION: Blood donations decreased between 2017 and 2019. Donations from younger donors continued to decline while donations among older donors have steadily increased. Prices paid for blood products by hospitals decreased. Implementation of PRT among blood centers and hospitals is slowly expanding.

[Relevance of safety measures to avoid HTLV transmission by transfusion in 2014]. / Pertinence des mesures sécuritaires transfusionnelles vis-à-vis du HTLV en 2014.

In high-income countries, the safety of blood transfusion related to viruses has reached a very high level, especially thanks to the implementation of multiple measures aimed at reducing the transfusion risk. The cost-effectiveness of these preventive measures is frequently discussed due to global financial resources, which are more and more limited. Hence, the revision of safety strategies is a key issue, especially when these strategies are redundant, as those implemented to avoid Human T-cell Lymphotropic Virus (HTLV) transmission, which are based on both antibodies screening and leucoreduction of blood products. The residual risk of the transmission of HTLV by transfusion has been recently estimated at 1 in 20 million donations (2010-2012) in France (excluding overseas territories). This estimation did not take into account the leucoreduction, which appears to be a very efficient preventive measure as the virus is strictly intra-cellular. To help decision-making, we have evaluated some parameters related to HTLV blood transmission. Firstly, the probability that an incident occurring during the leucoreduction process affects a HTLV-positive blood donation has been estimated at 1 in 178 million. Estimation of clinical consequences of HTLV-positive transfusions would affect 1 to 2 transfused-patients without leucoreduction, and one recipient every 192 years in case of 10% failures of the filtration method. Obviously, despite a risk, which appears to be controlled, HTLV screening will be disputed as soon as the efficiency of leucoreduction to totally prevent virus blood transmission will be proven and when pathogen inactivation methods are generalized to all blood cellular products.

Transfusion immunomodulation--the case for leukoreduced and (perhaps) washed transfusions.

During the last three decades, a growing body of clinical, basic science and animal model data has demonstrated that blood transfusions have important effects on the immune system. These effects include: dysregulation of inflammation and innate immunity leading to susceptibility to microbial infection, down-regulation of cellular (T and NK cell) host defenses against tumors, and enhanced B cell function that leads to alloimmunization to blood group, histocompatibility and other transfused antigens. Furthermore, transfusions alter the balance between hemostasis and thrombosis through inflammation, nitric oxide scavenging, altered rheologic properties of the blood, immune complex formation and, no doubt, several mechanisms not yet elucidated. The net effects are rarely beneficial to patients, unless they are in imminent danger of death due to exsanguination or life threatening anemia. These findings have led to appeals for more conservative transfusion practice, buttressed by randomized trials showing that patients do not benefit from aggressive transfusion practices. At the risk of hyperbole, one might suggest that if the 18th and 19th centuries were characterized by physicians unwittingly harming patients through venesection and bleeding, the 20th century was characterized by physicians unwittingly harming patients through current transfusion practices. In addition to the movement to more parsimonious use of blood transfusions, an effort has been made to reduce the toxic effects of blood transfusions through modifications such as leukoreduction and saline washing. More recently, there is early evidence that reducing the storage period of red cells transfused might be a strategy for minimizing adverse outcomes such as infection, thrombosis, organ failure and mortality in critically ill patients particularly at risk for these hypothesized effects. The present review will focus on two approaches, leukoreduction and saline washing, as means to reduce adverse transfusion outcomes.

Clinical effects of leucoreduction of blood transfusions.

For many years filtration for removal of leucocytes from red blood cell (RBC) and platelet transfusions was applied for selected patients to prevent cytomegalovirus (CMV) (re)activation, HLA immunisation and recurrent febrile nonhaemolytic transfusion reactions (FNHTR ). Since the 1980s, there was also growing concern about cancer recurrence and postoperative infections. In this review we discuss the studies on possible benefits of leucoreduction. In 2001 the Dutch Health Council decided that all blood products should undergo leucoreduction by filtration, as a precautionary measure to reduce possible transmission of variant Creutzfeld-Jacob disease (vCJD). The incidences of transfusion-transmitted CMV infection, HLA immunisation and FN HTR are decreased by universal leucoreduction. However, transfusion-related immunomodulation with presumed negative effects on cancer immunosurveillance, postoperative infections or aggravating organ failure, investigated in randomised controlled trials, revealed no support for extended indications for leucoreduction. An exception was seen in cardiac surgery where leucoreduction reduced short-term mortality by approximately 50%. The exact mechanism(s) for this effect is (are) not known. Pro-inf lammatory cytokines induced by eucocytecontaining RBC transfusions in combination with the inflammatory response after cardiac surgery may aggravate morbidity and could lead to mortality. In this review we discuss the evidence for the benefits of universal leucoreduction. Based on the available evidence, reversal to the use of buffy-coat depleted RBCs and restricted indications for leucoreduction by filtration (extended with open-heart surgery) is a safe option.

Leukocyte depletion during extracorporeal circulation allows better organ protection but does not change hospital outcomes.

BACKGROUND: Leukocyte filtration has been reported to reduce inflammatory damage during cardiopulmonary bypass. We evaluated the role of leukocyte filtration on hospital outcome and postoperative morbidity. METHODS: Eighty-two consecutive patients who underwent isolated coronary artery bypass grafting were randomly assigned (1:1) to receive leukocyte filters on both arterial and cardioplegia lines or standard arterial filters during cardiopulmonary bypass. Hospital outcome, postoperative markers of morbidity, and biochemical assays were compared. Data were collected preoperatively, intraoperatively, and postoperatively. Costs for patients receiving intraoperative leukofiltration were compared with control patients getting standard arterial filters. RESULTS: Hospital mortality and intensive care unit and hospital length of stay were similar. Although duration of ventilation and incidence of pneumonia were comparable, leukocyte-depleted patients showed a higher ratio of arterial partial pressure of oxygen to fraction of inspired oxygen (p = 0.008) and lower need for postoperative noninvasive ventilation (p = 0.041). Control patients showed higher need for continuous furosemide infusion (p = 0.013) and for renal replacement therapy (p = 0.014), in association with higher serum creatinine (p = 0.038) and blood urea (p = 0.18) and lower glomerular filtration rate (p = 0.038). Leukocyte-depleted patients required lower doses of inotropic agents (p = 0.56), whereas troponin I leakage and incidence of postoperative atrial fibrillation were comparable. No differences were found in terms of postoperative cerebral dysfunction or neutrophil and platelet counts, as well as postoperative bleeding and need for transfusions. Finally, leukodepletion proved significantly cost-beneficial, with a 37% cost reduction. CONCLUSIONS: Although hospital outcomes were similar in terms of mortality and length of stay, the improvements in pulmonary, renal, and myocardial function, in association with the cost benefit, justify the use of leukocyte-depletion filters in the clinical practice.

What is the role of leukocyte depletion in cardiac surgery?

Leukocytes play an important pathogenic role in ischaemia-reperfusion injury. During cardiopulmonary bypass, leukocyte filters have the potential to remove leukocytes, thereby reducing contact of activated leukocytes with the endothelium of target organs. Improvement in the safety and efficacy of commercially available leukocyte filters in recent years has led to their increasing use in cardiac surgery. However, the benefits have been inconsistent. Current evidence suggests that leukocyte depletion may not have a significant impact in low risk elective coronary artery bypass grafting but may be beneficial in valve surgery and high-risk cardiac surgery. High-risk surgical groups that may benefit from leukocyte filtration are those with left ventricular hypertrophy (LV mass>300 g), poor ejection fraction (EF<40%), chronic obstructive airways disease (predicted FEV1<75%), prolonged ischaemia (cross clamp time>120 min or cardiac transplantation), paediatric cardiac surgery and patients in cardiogenic shock requiring emergency coronary artery bypass grafting. Future trials should be powered to detect important clinical end points and be designed to avoid premature exhaustion of the filter.

Cost-effectiveness of leucocyte-depleted erythrocyte transfusion in cardiac valve surgery.

Cost-effectiveness of leucodepleted erythrocytes (LD) over buffy-coat-depleted packed cells (PC) is estimated from the primary dataset of a recently reported randomized clinical trial involving valve surgery (+/-CABG) patients. Data on the patient level of 474 adult patients who were randomized double-blind to LD or PC were used in order to calculate the healthcare costs and longevity per patient. The incremental cost-effectiveness ratio (ICER) in net costs per life-year gained was established from the healthcare perspective. Bootstrapping and cost-effectiveness acceptability curves were used in order to determine the confidence interval (CI) of the ICER. The longevity of patients in the PC and LD group was 10.6 and 11.4 years, respectively. Relative to PC, LD yielded an estimated 0.8 (95% CI = -0.27 to 1.84) life-year in the baseline. Adjusted for age and sex differences, health gains for LD are 0.4 life-year gained (95% CI = -0.67 to 1.44). Healthcare costs per patient averaged 10163 US dollars per patient in the PC group and 9949 US dollars in the LD group. Average cost-savings were 214 US dollars (95% CI = -1536 to 1964) per patient. Acceptability curves constructed from bootstrap simulations showed a probability of being cost-saving of 59% for universal leucodepletion from the healthcare perspective. The probability of adopting leucodepletion regardless of the costs reaches 92.7%. LD in patients receiving four or more transfusions showed the highest cost-savings and health gains. Leucodepletion of erythrocytes is a cost-saving strategy in cardiac valve (+/-CABG) patients. However, probablistic analysis failed to show a significant difference with buffy-coat-depleted PC.