The estimated negative impacts on the red blood cell inventory of reducing shelf-life at two large health authorities in British Columbia, Canada, using a discrete-event simulation model

BACKGROUND AND OBJECTIVES

Reducing the maximum red blood cell (RBC) shelf-life is under consideration due to potential negative effects of older blood. An assessment of the impacts of this change on blood supply chain management is evaluated.

MATERIALS AND METHODS

We performed a simulation study using data from 2017 to 2018 to estimate the outdate rate (ODR), STAT order and non-group-specific RBC transfusion at two Canadian health authorities (HAs).

RESULTS

Shortening shelf-life from 42 to 35 and 28 days led to the following: ODRs (in percentage) in both HAs increased from 0.52% (95% confidence interval [CI] 0.50-0.54) to 1.32% (95% CI 1.26-1.38) and 5.47% (95% CI 5.34-5.60), respectively (p < 0.05). The estimated yearly median of outdated RBCs increased from 220 (interquartile range [IQR] 199-242) to 549 (IQR 530-576) and 2422 (IQR 2308-2470), respectively (p < 0.05). The median number of outdated redistributed units increased from 152 (IQR 136-168) to 356 (IQR 331-369) and 1644 (IQR 1591-1741), respectively (p < 0.05). The majority of outdated RBC units were from redistributed units rather than units ordered from the blood supplier. The estimated weekly mean STAT orders increased from 11.4 (95% CI 11.2-11.5) to 14.1 (95% CI 13.1-14.3) and 20.9 (95% CI 20.6-21.1), respectively (p < 0.001). The non-group-specific RBC transfusion rate increased from 4.7% (95% CI 4.6-4.8) to 8.1% (95% CI 7.9-8.3) and 15.6% (95% CI 15.3-16.4), respectively (p < 0.001). Changes in ordering schedules, decreased inventory levels and fresher blood received simulated minimally mitigated these impacts.

CONCLUSION

Decreasing RBC shelf-life negatively impacted RBC inventory management, including increasing RBC outdating and STAT orders, which supply modifications minimally mitigate.

Recommendations for in vitro evaluation of blood components collected, prepared and stored in non-DEHP medical devices

BACKGROUND AND OBJECTIVES

DEHP, di(2-ethylhexyl) phthalate, is the most common member of the class of ortho-phthalates, which are used as plasticizers. The Medical Device Regulation has restricted the use of phthalates in medical devices. Also DEHP has been added to the Annex XIV of REACH, "Registration, Evaluation, Authorisation and Restriction of Chemicals" due to its endocrine disrupting properties to the environment. As such, the sunset date for commercialisation of DEHP-containing blood bags is May 27^th 2025. There are major concerns in meeting this deadline as these systems have not yet been fully validated and/or CE-marked. Also, since DEHP is known to affect red cell quality during storage, it is imperative to transit to non-DEHP without affecting blood product quality. Here, EBA members aim to establish common grounds on the evaluation and assessment of blood components collected, prepared and stored in non-DEHP devices.

MATERIALS AND METHODS

Based on data as well as the input of relevant stakeholders a rationale for the validation of each component was composed.

RESULTS

The red cell components will require the most extensive validation as their quality is directly affected by the absence of DEHP, as opposed to platelet and plasma components.

CONCLUSION

Studies in the scope of evaluating the quality of blood products obtained with non-DEHP devices, under the condition that they are carried out according to these recommendations, could be used by all members of the EBA to serve as scientific support in the authorization process specific to their jurisdiction or for their internal validation use.

Colloid osmotic pressure of contemporary and novel transfusion products

Background and Objectives

Colloid osmotic pressure (COP) is a principal determinant of intravascular fluid homeostasis and a pillar of fluid therapy and transfusion. Transfusion‐associated circulatory overload (TACO) is a leading complication of transfusion, and COP could be responsible for recruiting additional fluid. Study objective was to measure COP of blood products as well as investigate the effects of product concentration and storage lesion on COP.

Materials and Methods

Three units of each product were sampled longitudinally. COP was measured directly as well as the determinants thereof albumin and total protein. Conventional blood products, that is red blood cell (RBC), fresh‐frozen plasma (FFP) and platelet concentrates (PLTs), were compared with their concentrated counterparts: volume‐reduced RBCs, hyperconcentrated PLTs, and fully and partially reconstituted lyophilized plasma (prLP). Fresh and maximally stored products were measured to determine changes in protein and COP. We calculated potential volume load (PVL) to estimate volume recruited using albumin's water binding per product.

Results

Colloid osmotic pressure varies widely between conventional products (RBCs, 1·9; PLTs, 7·5; and FFP, 20·1 mmHg); however, all are hypooncotic compared with human plasma COP (25·4 mmHg). Storage lesion did not increase COP. Concentrating RBCs and PLTs did not increase COP; only prLP showed a supraphysiological COP of 47·3 mm Hg. The PVL of concentrated products was lower than conventional products.

Conclusion

Colloid osmotic pressure of conventional products was low. Therefore, third‐space fluid recruitment is an unlikely mechanism in TACO. Concentrated products had a lower calculated fluid load and may prevent TACO. Finally, storage did not significantly increase oncotic pressure of blood products.

Comparison of UV spectrometry and fluorometry-based methods for quantification of cell-free DNA in red cell components

BACKGROUND:

Stress and shear force applied on blood components during processing and storage may induce cellular damage leading to release of cell-free DNA (cfDNA). In this study, we have compared ultraviolet (UV) spectrophotometry with UV-induced fluorescence for the quantification of cfDNA in red cell supernatant.

MATERIALS AND METHODS:

cfDNA was extracted from 200 μL sample of supernatants from 99 packed red blood cells using QIAamp DNA Blood Mini Kit (Qiagen, Germany). Quantification of cfDNA was done using two different methods: one based on spectrophotometry (NanoDrop 2000c, ThermoFisher Scientific, USA) and another based on fluorometry (Qubit 2.0, Life Technologies, ThermoFisher Scientific, USA). Interassay variability of both the methods was estimated using serial dilutions of standard with known DNA concentration.

RESULTS:

DNA quantification by both the methods was close to actual amount of known standard in dilutions with higher concentration of DNA (21.68 to 2.71 ng/μl). While at higher dilutions, quantification by NanoDrop was neither precise nor accurate. Median cfDNA concentration in the study units was found to be 1.60 ng/μl (25^th–75^th percentile range: 1.10–2.10) by UV spectrophotometry (NanoDrop) compared to 0.080 ng/μl (25^th–75^th percentile range: 0.050–0.130) by fluorometry (Qubit).

CONCLUSION:

Due to high interassay variability between the two methods and the better precision and accuracy of Qubit, it is recommended that fluorometry-based method be used for the quantification of cfDNA in blood components.

The systematic use of evidence-based methodologies and technologies enhances shared decision-making in the 2018 International Consensus Conference on Patient Blood Management

BACKGROUND AND OBJECTIVES

Patient Blood Management (PBM) aims to optimize the care of patients who might need a blood transfusion. The International Consensus Conference on PBM (ICC-PBM) aimed to develop evidence-based recommendations on three topics: preoperative anaemia, red blood cell transfusion thresholds and implementation of PBM programmes. This paper reports how evidence-based methodologies and technologies were used to enhance shared decision-making in formulating recommendations during the ICC-PBM.

MATERIALS & METHODS

Systematic reviews on 17 PICO (Population, Intervention, Comparison, Outcomes) questions were conducted by a Scientific Committee (22 international topic experts and one methodologist) according to GRADE (Grades of Recommendation, Assessment, Development and Evaluation) methodology. Evidence-based recommendations were formulated using Consensus Development Conference methodology.

RESULTS

We screened 17 607 references and included 145 studies. The overall certainty in the evidence of effect estimates was generally low or very low. During the ICC, plenary sessions (100-200 stakeholders from a range of clinical disciplines and community representatives) were followed by closed sessions where multidisciplinary decision-making panels (>50 experts and patient organizations) formulated recommendations. Two chairs (content-expert and methodologist) moderated each session and two rapporteurs documented the discussions. The Evidence-to-Decision template (GRADEpro software) was used as the central basis in the process of formulating recommendations.

CONCLUSION

This ICC-PBM resulted in 10 clinical and 12 research recommendations supported by an international stakeholder group of experts in blood transfusion. Systematic, rigorous and transparent evidence-based methodology in a formal consensus format should be the new standard to evaluate (cost-) effectiveness of medical treatments, such as blood transfusion.

Not all red cell concentrate units are equivalent: international survey of processing and in vitro quality data

INTRODUCTION

In vitro qualitative differences exist in red cell concentrates (RCCs) units processed from whole blood (WB) depending on the method of processing. Minimal literature exists on differences in processing and variability in quality data. Therefore, we collected information from blood manufacturers worldwide regarding (1) details of WB collection and processing used to produce RCCs and (2) quality parameters and testing as part of routine quality programmes.

METHODS

A secure web-based survey was developed, refined after pilot data collection and distributed to blood centres. Descriptive analyses were performed.

RESULTS

Data from ten blood centres in nine countries were collected. Six blood centres (60%) processed RCCs using the top-and-top (TAT) method which produces RCCs and plasma, and eight centres (80%) used the bottom-and-top (BAT) which additionally produces buffy coat platelets. Five of the centres used both processing methods; however, four favoured BAT processing. One centre utilized the Reveos automated system exclusively. All centres performed pre-storage leucoreduction. Other parameters demonstrated variability, including active cooling at collection, length of hold before processing, donor haemoglobin limits, acceptable collection weights, collection sets, time to leucoreduction, centrifugation speeds, extraction devices and maximum RCC shelf life. Quality marker testing also differed amongst blood centres. Trends towards higher RCC unit volume, haemolysis and residual leucoctyes were seen in the TAT compared with BAT processing across centres.

CONCLUSION

Methods and parameters of WB processing and quality testing of RCCs differ amongst surveyed blood manufacturers. Further studies are needed to assess variations and to potentially improve methods and product quality.

Amustaline (S-303) treatment inactivates high levels of Chikungunya virus in red-blood-cell components

BACKGROUND AND OBJECTIVES

Chikungunya virus (CHIKV) infections have been reported in all continents, and the potential risk for CHIKV transfusion-transmitted infections (TTIs) was demonstrated by the detection of CHIKV RNA-positive donations in several countries. TTIs can be reduced by pathogen inactivation (PI) of blood products. In this study, we evaluated the efficacy of amustaline and glutathione (S-303/GSH) to inactivate CHIKV in red-blood-cell concentrates (RBCs).

MATERIAL AND METHODS

Red-blood-cells were spiked with high level of CHIKV. Infectious titres and RNA loads were measured before and after PI treatment. Residual CHIKV infectivity was also assessed after five successive cell culture passages.

RESULTS

The mean CHIKV titres in RBCs before inactivation was 5·81 ± 0·18 log₁₀ 50% tissue culture infectious dose (TCID₅₀ )/mL, and the mean viral RNA load was 10·49 ± 0·15 log₁₀ genome equivalent (GEq)/mL. No CHIKV TCID was detected after S-303 treatment nor was replicative CHIKV particles and viral RNA present after five cell culture passages of samples obtained immediately after S-303 treatment.

CONCLUSION

Chikungunya virus was previously shown to be inactivated by the PI technology using amotosalen and ultraviolet A light for the treatment of plasma and platelets. This new study demonstrates that S-303/GSH can inactivate high titres of CHIKV in RBCs.

Towards bedside washing of stored red blood cells: a prototype of a simple apparatus based on microscale sedimentation in normal gravity

BACKGROUND AND OBJECTIVES

Infusion of by-products of red blood cell (RBC) storage-induced degradation as well as of the residual plasma proteins and the anticoagulant-preservative solution contained in units of stored blood serve no therapeutic purpose and may be harmful to some patients. Here, we describe a prototype of a gravity-driven system for bedside washing of stored RBCs.

MATERIALS AND METHODS

Stored RBCs were diluted to 10% haematocrit (Hct) with normal saline, matching the conventional washing procedure. The dilute RBC suspensions were passed through a column of coiled tubing to allow RBC sedimentation in normal gravity, thus separating them from the washing solution. Washed RBCs were collected using bifurcations located along the tubing. Washing efficiency was quantified by measuring Hct, morphology, deformability, free haemoglobin and total-free protein.

RESULTS

The gravity-driven washing system operating at 0·5 ml/min produced washed RBCs with final Hct of 36·7 ± 3·4% (32·3-41·2%, n = 10) and waste Hct of 3·4 ± 0·7% (2·4-4·3%, n = 10), while removing 80% of free haemoglobin and 90% of total-free protein. Washing improved the ability of stored RBCs to perfuse an artificial microvascular network by 20%. The efficiency of washing performed using the gravity-driven system was not significantly different than that of conventional centrifugation.

CONCLUSIONS

This proof-of-concept study demonstrates the feasibility of washing stored RBCs using a simple, disposable system with efficiency comparable to that of conventional centrifugation, and thus represents a significant first step towards enabling low-cost washing of stored blood at bedside.

Haem is associated with thrombosis in neonates and infants undergoing cardiac surgery for congenital heart disease

BACKGROUND

Haem levels are associated with thrombosis in a variety of diseases, as well as being a contributing cause of thrombotic events in animal models.

MATERIALS AND METHODS

We retrospectively analyzed samples from 39 children who underwent cardiac surgery with cardiopulmonary bypass, including 15 children who developed a postoperative thrombosis and 24 controls.

RESULTS

Patients who developed thrombosis postoperatively had statistically significant higher average haem levels over time (presurgery to 12 h postsurgery) compared to patients who did not develop thrombosis.

CONCLUSION

Higher cell-free total haem levels are associated with a higher risk of thrombosis in a paediatric cardiac surgical cohort.

Changes in circulating inflammatory markers following febrile non-haemolytic transfusion reactions to leucoreduced red cells

It would be desirable to be able to distinguish fever as a result of febrile non-haemolytic transfusion reactions (FNHTR) from other febrile conditions. To further characterize the inflammatory feature of FNHTR, we measured a large panel of inflammatory markers in pre- and posttransfusion plasma samples from patients with and without FNHTR following the transfusion of leucoreduced red blood cells. As FNHTR patients only displayed a significant increase in IL-6, we conclude that changes in plasma cytokine levels during FNHTR are unlikely to be used diagnostically. An incidental finding of a distinct cytokine pattern in pretransfusion samples from FNHTR patients warrants further investigations, as it might be used to characterize the nature of FNHTR and to predict the risk of these adverse events.

Reduction of biological response modifiers in the supernatant of washed paediatric red blood cells

BACKGROUND

Washing of red blood cells (RBC) can reduce unwanted biological response modifiers (BRMs) that can mediate transfusion complications in infants. The aim of this study was to examine the in vitro quality and the changes in BRMs following washing in paediatric RBC units.

MATERIALS AND METHODS

A pool and split design was used to prepare RBC (either 1 or 4 days old; n = 26 pairs). One unit was washed with 0·9% saline by centrifugation and then resuspended in SAG-M, while the other remained unwashed. Each RBC unit was divided to produce four units of paediatric-sized components. Samples were taken after 3 h and subsequently on days 1, 2, 7 and 14 post-wash.

RESULTS

Washing of RBC resulted in some red cell loss, with a minor increase in haemolysis. Washing effectively reduced supernatant potassium and IgA, as well as cytokines and complement proteins. RBC microparticles were significantly reduced in RBC washed at 1, but not 4 days post-collection. Incubation with supernatant from unwashed but not washed RBC led to endothelial cell activation, with increased cell surface expression of CD62E (E-selectin) and CD106 (VCAM).

CONCLUSION

Although washing affected some aspects of the in vitro quality of RBC, it effectively reduced the concentration and activity of BRMs in the supernatant of RBC. Such a reduction may be clinically beneficial in selected patient groups.

Transfusion of recently donated (fresh) red blood cells (RBCs) does not improve survival in comparison with current practice, while safety of the oldest stored units is yet to be established: a meta-analysis

BACKGROUND AND OBJECTIVES

Preclinical studies generated the hypothesis that older stored red blood cells (RBCs) can increase transfusion risks. To examine the most updated and complete clinical evidence and compare results between two trial designs, we assessed both observational studies and randomized controlled trials (RCTs) studying the effect of RBC storage age on mortality.

MATERIALS AND METHODS

Five databases were searched through December 2014 for studies comparing mortality using transfused RBCs having longer and shorter storage times.

RESULTS

Analysis of six RCTs found no significant differences in survival comparing current practice (average storage age of 2 to 3 weeks) to transfusion of 1- to 10-day-old RBCs (OR 0·91, 95% CI 0·77-1·07). RBC storage age was lower in RCTs vs. observational studies (P = 0·01). The 31 observational studies found an increased risk of death (OR 1·13, 95% CI 1·03-1·24) (P = 0·01) with increasing age of RBCs, a different mortality effect than RCTs (P = 0·02).

CONCLUSION

RCTs established that transfusion of 1- to 10-day-old stored RBCs is not superior to current practice. The apparent discrepancy in mortality between analyses of RCTs and observational studies may in part relate to differences in hypotheses tested and ages of stored RBCs studied. Further trials investigating 1- to 10-day-old stored RBC benefits would seem of lower priority than studies to determine whether 4- to 6-week stored units have safety and efficacy equivalent to the 2- to 3-week-old stored RBCs commonly transfused today.

Storage of washed or irradiated red cells in AS-7 improves their in vitro characteristics

BACKGROUND

AS-7 is a new alkaline hypotonic red cell additive solution (AS) shown to improve red cell quality during storage compared with AS-1. We sought to compare red cells stored in AS-7 with those stored in SAGM using RCC that were either untreated, or washed or irradiated on day 14 of storage.

STUDY DESIGN AND METHODS

A pooled and split study design was used to produce seven identical RCC (four in SAGM and three in AS-7). At day 14 following donation, two RCC (one in SAGM and one in AS-7) were gamma irradiated and three RCC (two in SAGM and one in AS-7) were washed and resuspended in either SAGM or AS-7. RCC were sampled for analysis throughout storage and at end of shelf life: day 28 for washed or irradiated and day 35 for untreated RCC.

RESULTS

For untreated, washed or irradiated RCC, those stored in AS-7 had lower haemolysis, red cell microvesicles and supernatant potassium content than RCC in SAGM. In addition, ATP levels and pH were better maintained in AS-7 RCC than in SAGM RCC.

CONCLUSION

These data suggest that the quality of these components may be improved by storage in AS-7 compared with SAGM.

Transfusion of fresh vs. older red blood cells in the context of infection

The red blood cell (RBC) storage interval has been extended from less than a week to the current storage interval of 6-8 weeks. Regulatory criteria for extending storage rely upon a minimal degree of hemolysis and acceptable in vivo 24-h post transfusion recovery. Clinical studies of safety and efficacy have never been required. Concerns have arisen that RBC toward the end of storage develop a 'storage lesion' with previously unrecognized toxicity. Of the several mechanisms proposed, the bolus of iron delivered to macrophages as a result of hemolysis of stored RBC might pose a particular risk to patients with existing infections. We developed a canine model of pneumonia to compare the toxicity of stored RBC transfusion. We described increased mortality after transfusion of old RBC. We found that transfused older RBC increased mortality, in vivo hemolysis, circulating cell-free hemoglobin that scavenges nitric oxide, and elevations of non-transferrin bound and plasma labile iron. Disappearance of circulating iron correlated with increased mortality, worsening pulmonary function, and bacterial proliferation. Washing decreased the mortality associated with transfusing older RBC, but had the opposite effect on fresher blood. With low doses of bacteria, survival was unaffected by the age of blood, whereas high bacteria doses masked any effect of RBC age on mortality. Older RBC may have adverse effects, but the patient's clinical status, the age, volume and method of preparation of the RBC may be critical variables. Several mechanisms may account for this toxicity, but in the presence of bacterial infection, availability of iron likely plays a major role.

Glucose-6-phosphate dehydrogenase deficiency in Italian blood donors: prevalence and molecular defect characterization

BACKGROUND

In the countries with high G6PD deficiency prevalence, blood donors are not routinely screened for this genetic defect. G6PD deficiency is often asymptomatic, blood donors may be carriers of the deficiency without being aware of it. The aim of the study was to evaluate the prevalence of G6PD deficiency among the Italian blood donors.

DESIGN AND METHODS

From October 2009 to April 2011, 3004 blood donors from a large hospital transfusion centre were screened for G6PD deficiency using differential pH-metry and the characterization of G6PD mutations was performed on G6PD-deficient subjects. The haematological features of G6PD-deficient and normal donors were also compared.

RESULTS

Thirty-three subjects (25 men and 8 women) with low G6PD activity were identified, corresponding to 1·1% of the examined blood donor population. The frequencies of class II severe alleles (Mediterranean, Valladolid, Chatham and Cassano) and class III mild alleles (Seattle, A- and Neapolis) were 48% and 43%, respectively. The haematological parameters of G6PD- donors were within normal range; however, the comparison between normal and G6PD- class II donors showed significant differences.

CONCLUSION

In Italy, the presence of blood donors with G6PD deficiency is not a rare event and the class II severe variants are frequent. The identification of G6PD-deficient donors and the characterization of the molecular variants would prevent the use of G6PD-deficient RBC units when the haemolytic complications could be relevant especially for high risk patients as premature infants and neonates and patients with sickle cell disease submitted to multiple transfusions.

Haemoglobin glycation (Hb1Ac) increases during red blood cell storage: a MALDI-TOF mass-spectrometry-based investigation

Haemoglobin A1c (HbA1c ) represents a key biomarker in diabetes diagnosis and management, as it is indicative of recent blood glucose concentrations. Glycation of haemoglobin is a non-enzymatic irreversible process that is promoted by the prolonged exposure of erythrocytes to high glucose concentrations, a condition that is known to occur under blood banking conditions. However, controversial data indicate no clear hint as to whether and to which extent HbA1c accumulates during red blood cell storage. Hereby, we propose the application of a validated MALDI-TOF mass-spectrometry-based method to this issue and report the observation about HbA1c levels apparently increasing over storage progression.

Stored blood transfusion induces transient pulmonary arterial hypertension without impairing coagulation in an ovine model of nontraumatic haemorrhage

BACKGROUND AND OBJECTIVES

Transfusion of blood products in particular older products is associated with patient morbidity. Previously, we demonstrated a higher incidence of acute lung injury in lipopolysaccharide-treated sheep transfused with stored blood products. As transfusion following haemorrhage is more common, we aimed to determine whether a 'first hit' of isolated haemorrhage would precipitate similar detrimental effects following transfusion and also disrupt haemostasis.

MATERIALS AND METHODS

Anaesthetized sheep had 33% of their total blood volume collected into Leukotrap bags (Pall Medical), which were processed into packed red blood cells and cross-matched for transfusion into other sheep. After 30 mins, the sheep were resuscitated with either: fresh (<5 days old) or stored (35-42 days old) ovine blood followed by 4% albumin to replacement volume, albumin alone or normal saline alone and monitored for 4 h.

RESULTS

The first hit of haemorrhage precipitated substantial decreases in mean arterial pressure however haemostasis was preserved. Transfusion of stored ovine blood induced (1) transient pulmonary arterial hypertension but no oedema and (2) reduced fibrinogen levels more than fresh blood, but neither induced coagulopathy. Thus, transfusion of stored blood affected pulmonary function even in the absence of overt organ injury.

CONCLUSION

The fact that stored blood transfusions: (1) did not induce acute lung injury in contrast to previous lipopolysaccharide-primed animal models identifies the 'first hit' as an important determinant of the severity of transfusion-mediated injury; (2) impaired pulmonary dynamics verifies the sensitivity and vulnerability of the pulmonary system to injury.