Alteration of red cell aggregability and shape during blood storage

Perioperative Plasma in Addition to Red Blood Cell Transfusions Is Associated With Increased Venous Thromboembolism Risk Postoperatively

BACKGROUND

Perioperative red blood cell (RBC) transfusions increase venous thromboembolic (VTE) events. Although a previous study found that plasma resuscitation after trauma was associated with increased VTE, the risk associated with additional perioperative plasma is unknown.

METHODS

A US claims and EHR database (TriNetX Diamond Network) was queried. We compared surgical patients who received perioperative plasma and RBC to patients who received perioperative RBC but not plasma. Subanalyses included (1) all surgeries (n = 48,580) and (2) cardiovascular surgeries (n = 38,918). Propensity score matching was performed for age at surgery, ethnicity, race, sex, overweight and obesity, type 2 diabetes, disorders of lipoprotein metabolism, essential hypertension, neoplasms, nicotine dependence, coagulopathies, sepsis, chronic kidney disease, liver disease, nonsteroidal anti-inflammatory analgesics, platelet aggregation inhibitors, anticoagulants, hemoglobin level, outpatient service utilization, and inpatient services; surgery type was included for "all surgeries" analyses. Outcomes included 30-day mortality, postoperative VTE, pulmonary embolism (PE), and disseminated intravascular coagulation (DIC).

RESULTS

After matching the surgical cohorts, compared to only RBC, plasma + RBC was associated with higher risk of postoperative mortality (4.52% vs 3.32%, risk ratio [RR]: 1.36 [95% confidence interval, 1.24-1.49]), VTE (3.92% vs 2.70%, RR: 1.36 [1.24-1.49]), PE (1.94% vs 1.33%, RR: 1.46 [1.26-1.68]), and DIC (0.96% vs 0.35%, RR: 2.75 [2.15-3.53]). Among perioperative cardiovascular patients, adding plasma to RBC transfusion was associated with similar increased risk.

CONCLUSIONS

When compared with perioperative RBC transfusion, adding plasma was associated with increased 30-day postoperative mortality, VTE, PE, and DIC risk among surgical and cardiovascular surgical patients. Reducing unnecessary plasma transfusion should be a focus of patient blood management to improve overall value in health care.

Low-Dose Dietary Fish Oil Improves RBC Deformability without Improving Post-Transfusion Recovery in Mice

Long-chain polyunsaturated fatty acids (LC-PUFAs) are important modulators of red blood cell (RBC) rheology. Dietary LC-PUFAs are readily incorporated into the RBC membrane, improving RBC deformability, fluidity, and hydration. Female C57BL/6J mice consumed diets containing increasing amounts of fish oil (FO) ad libitum for 8 weeks. RBC deformability, filterability, and post-transfusion recovery (PTR) were evaluated before and after cold storage. Lipidomics and lipid peroxidation markers were evaluated in fresh and stored RBCs. High-dose dietary FO (50%, 100%) was associated with a reduction in RBC quality (i.e., in vivo lifespan, deformability, lipid peroxidation) along with a reduced 24 h PTR after cold storage. Low-dose dietary FO (6.25-12.5%) improved the filterability of fresh RBCs and reduced the lipid peroxidation of cold-stored RBCs. Although low doses of FO improved RBC deformability and reduced oxidative stress, no improvement was observed for the PTR of stored RBCs. The improvement in RBC deformability observed with low-dose FO supplementation could potentially benefit endurance athletes and patients with conditions resulting from reduced perfusion, such as peripheral vascular disease.

Dose-dependent effects of red blood cell transfusion and case mix index on venous thromboembolic events in spine surgery

BACKGROUND AND OBJECTIVES

Venous thromboembolic (VTE) events represent a major source of morbidity and mortality in spine surgery. Our goal was to assess whether a dose-response relationship exists between red blood cell (RBC) transfusion and postoperative VTE events among spine surgery patients.

MATERIALS AND METHODS

A total of 786 spine surgery patients at a single institution who received at least 1 RBC unit perioperatively were included (2016-2019). Patients were stratified based on RBC transfusion volume: 1-2 units (39.3%), 3-4 units (29.4%), 5-6 units (15.9%) and ≥7 units (15.4%). Subgroup analyses were performed after stratification by case mix index, a standardized surrogate for patients' disease severity and comorbidities. Multivariable regression was used to assess risk factors for the development of postoperative VTE events.

RESULTS

The overall VTE event rate was 2.4% (n = 19). A dose-response relationship was seen between RBC transfusion volume and VTE events (1-2 units: 0.97%, 3-4 units: 1.30%, 5-6 units: 3.20%, ≥7 units: 7.44%; p < 0.01). Similar dose-response relationships were seen between case mix index and VTE events (1.00-3.99: 0.52%, 4.00-6.99: 2.68%, ≥7.00: 9.00%; p < 0.01). On multivariable regression, larger RBC transfusion volumes (adjusted odds ratio [OR] 1.18 per RBC unit, 95% confidence interval [CI] 1.07-1.29; p < 0.01) and higher case mix index scores (adjusted OR 1.39 per unit increase, 95% CI 1.14-1.69; p < 0.01) were associated with an increased risk of thrombosis.

CONCLUSION

Larger RBC transfusion volumes and higher case mix index scores were associated with an increased risk of VTE events. Physicians should be aware of how these dose-response relationships can influence a patient's risk of developing thrombotic complications postoperatively.

Intermittent scavenging of storage lesion from stored red blood cells by electrospun nanofibrous sheets enhances their quality and shelf-life

Transfusion of healthy red blood cells (RBCs) is a lifesaving process. However, upon storing RBCs, a wide range of damage-associate molecular patterns (DAMPs), such as cell-free DNA, nucleosomes, free-hemoglobin, and poly-unsaturated-fatty-acids are generated. DAMPs can further damage RBCs; thus, the quality of stored RBCs declines during the storage and limits their shelf-life. Since these DAMPs consist of either positive or negative charged species, we developed taurine and acridine containing electrospun-nanofibrous-sheets (Tau-AcrNFS), featuring anionic, cationic charges and an DNA intercalating group on their surfaces. We show that Tau-AcrNFS are efficient in scavenging DAMPs from stored human and mice RBCs ex vivo. We find that intermittent scavenging of DAMPs by Tau-AcrNFS during the storage reduces the loss of RBC membrane integrity and reduces discocytes-to-spheroechinocytes transformation in stored-old-RBCs. We perform RBC-transfusion studies in mice to reveal that intermittent removal of DAMPs enhances the quality of stored-old-RBCs equivalent to freshly collected RBCs, and increases their shelf-life by ~22%. Such prophylactic technology may lead to the development of novel blood bags or medical device, and may therefore impact healthcare by reducing transfusion-related adverse effects.

Large Animal Models for Simulating Physiology of Transfusion of Red Cell Concentrates-A Scoping Review of The Literature

Background and Objectives: Transfusion of red cell concentrates is a key component of medical therapy. To investigate the complex transfusion-associated biochemical and physiological processes as well as potential risks for human recipients, animal models are of particular importance. This scoping review summarizes existing large animal transfusion models for their ability to model the physiology associated with the storage of erythrocyte concentrates. Materials and Methods: The electronic databases PubMed, EMBASE, and Web of Science were systematically searched for original studies providing information on the intravenous application of erythrocyte concentrates in porcine, ovine, and canine animal models. Results: A total of 36 studies were included in the analysis. The majority of porcine studies evaluated hemorrhagic shock conditions. Pig models showed high physiological similarities with regard to red cell physiology during early storage. Ovine and canine studies were found to model typical aspects of human red cell storage at 42 days. Only four studies provided data on 24 h in vivo survival of red cells. Conclusions: While ovine and canine models can mimic typical human erythrocyte storage for up to 42 days, porcine models stand out for reliably simulating double-hit pathologies such as hemorrhagic shock. Large animal models remain an important area of translational research since they have an impact on testing new pharmacological or biophysical interventions to attenuate storage-related adverse effects and allow, in a controlled environment, to study background and interventions in dynamic and severe disease conditions.

Epidemiological status and risk factors of deep vein thrombosis in patients with femoral neck fracture

Objectives

The purpose of this study was to investigate the incidence of deep vein thrombosis (DVT) and clarify the risk factors of DVT in patients with femoral neck fracture.

Methods

A self-designed questionnaire was used to collect the clinical data of 1209 patients with femoral neck fracture in our hospital from January 2019 to December 2019. The content of the questionnaire mainly includes general information, past medical history, history of present illness, operation related information, occurrence of DVT. The collected data were entered into Excel to analyze the incidence and risk factors of DVT in patients with femoral neck fracture. Chi square test and binary logistic regression model was used to screen the risk factors of DVT.

Results

1209 cases of femoral neck fracture were included in this study. The incidence of DVT was 28.0% (339 patients). Among them, 71.7% (243 patients) were preoperative DVT and 28.3% (96 patients) were postoperative DVT. For the risk-factor analysis, gender, age, time from injury to hospitalization, operative method, anesthesia method and intraoperative blood loss were independent risk factors for DVT.

Conclusion

The incidence of DVT in patients with femoral neck fracture is relatively high, and there are many related risk factors.

Deuterated Linoleic Acid Attenuates the RBC Storage Lesion in a Mouse Model of Poor RBC Storage

Background: Long-chain polyunsaturated fatty acids (PUFAs) are important modulators of red blood cell (RBC) rheology. Dietary PUFAs are readily incorporated into the RBC membrane, improving RBC deformability, fluidity, and hydration. However, enriching the lipid membrane with PUFAs increases the potential for peroxidation in oxidative environments (e.g., refrigerated storage), resulting in membrane damage. Substitution of bis-allylic hydrogens with deuterium ions in PUFAs decreases hydrogen abstraction, thereby inhibiting peroxidation. If lipid peroxidation is a causal factor in the RBC storage lesion, incorporation of deuterated linoleic acid (DLA) into the RBC membrane should decrease lipid peroxidation, thereby improving RBC lifespan, deformability, filterability, and post-transfusion recovery (PTR) after cold storage. Study Design and Methods: Mice associated with good (C57BL/6J) and poor (FVB) RBC storage quality received diets containing 11,11-D2-LA Ethyl Ester (1.0 g/100 g diet; deuterated linoleic acid) or non-deuterated LA Ethyl Ester (control) for 8 weeks. Deformability, filterability, lipidomics, and lipid peroxidation markers were evaluated in fresh and stored RBCs. Results: DLA was incorporated into RBC membranes in both mouse strains. DLA diet decreased lipid peroxidation (malondialdehyde) by 25.4 and 31% percent in C57 mice and 12.9 and 79.9% in FVB mice before and after cold storage, respectively. In FVB, but not C57 mice, deformability filterability, and post-transfusion recovery were significantly improved. Discussion: In a mouse model of poor RBC storage, with elevated reactive oxygen species production, DLA attenuated lipid peroxidation and significantly improved RBC storage quality.

Contribution of Various Types of Transfusion to Acute and Delayed Intracerebral Hemorrhage Injury

Intracerebral hemorrhage (ICH) is the second most prevalent type of stroke, after ischemic stroke, and has exceptionally high morbidity and mortality rates. After spontaneous ICH, one primary goal is to restrict hematoma expansion, and the second is to limit brain edema and secondary injury. Various types of transfusion therapies have been studied as treatment options to alleviate the adverse effects of ICH etiopathology. The objective of this work is to review transfusions with platelets, fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), and red blood cells (RBCs) in patients with ICH. Furthermore, tranexamic acid infusion studies have been included due to its connection to ICH and hematoma expansion. As stated, the first line of therapy is limiting bleeding in the brain and hematoma expansion. Platelet transfusion is used to promote recovery and mitigate brain damage, notably in patients with severe thrombocytopenia. Additionally, tranexamic acid infusion, FFP, and PCC transfusion have been shown to affect hematoma expansion rate and volume. Although there is limited available research, RBC transfusions have been shown to cause higher tissue oxygenation and lower mortality, notably after brain edema, increases in intracranial pressure, and hypoxia. However, these types of transfusion have varied results depending on the patient, hemostasis status/blood thinner, hemolysis, anemia, and complications, among other variables. Inconsistencies in published results on various transfusion therapies led us to review the data and discuss issues that need to be considered when establishing future guidelines for patients with ICH.

Perioperative Care of Patients at High Risk for Stroke During or After Non-cardiac, Non-neurological Surgery: 2020 Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care

Perioperative stroke is associated with considerable morbidity and mortality. Stroke recognition and diagnosis are challenging perioperatively, and surgical patients receive therapeutic interventions less frequently compared with stroke patients in the outpatient setting. These updated guidelines from the Society for Neuroscience in Anesthesiology and Critical Care provide evidence-based recommendations regarding perioperative care of patients at high risk for stroke. Recommended areas for future investigation are also proposed.

Do We Store Packed Red Blood Cells under "Quasi-Diabetic" Conditions?

Red blood cell (RBC) transfusion is one of the most common therapeutic procedures in modern medicine. Although frequently lifesaving, it often has deleterious side effects. RBC quality is one of the critical factors for transfusion efficacy and safety. The role of various factors in the cells’ ability to maintain their functionality during storage is widely discussed in professional literature. Thus, the extra- and intracellular factors inducing an accelerated RBC aging need to be identified and therapeutically modified. Despite the extensively studied in vivo effect of chronic hyperglycemia on RBC hemodynamic and metabolic properties, as well as on their lifespan, only limited attention has been directed at the high sugar concentration in RBCs storage media, a possible cause of damage to red blood cells. This mini-review aims to compare the biophysical and biochemical changes observed in the red blood cells during cold storage and in patients with non-insulin-dependent diabetes mellitus (NIDDM). Given the well-described corresponding RBC alterations in NIDDM and during cold storage, we may regard the stored (especially long-stored) RBCs as “quasi-diabetic”. Keeping in mind that these RBC modifications may be crucial for the initial steps of microvascular pathogenesis, suitable preventive care for the transfused patients should be considered. We hope that our hypothesis will stimulate targeted experimental research to establish a relationship between a high sugar concentration in a storage medium and a deterioration in cells’ functional properties during storage.

Storage-Related Changes in Autologous Whole Blood and Irradiated Allogeneic Red Blood Cells and Their Ex Vivo Effects on Deformability, Indices, and Density of Circulating Erythrocytes in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass

OBJECTIVES

Blood-processing techniques and preservation conditions cause storage lesions, possibly leading to adverse outcomes after transfusion. The authors investigated the metabolic changes and deformability of red blood cells (RBCs) during storage and determined the effect of storage lesions on circulating RBCs during cardiac surgery.

DESIGN

Prospective study.

SETTING

Tertiary care center affiliated with a university hospital.

PARTICIPANTS

Adults who underwent elective cardiac surgery requiring cardiopulmonary bypass.

INTERVENTIONS

The authors collected aliquots of autologous and irradiated allogeneic RBCs and blood samples from seven patients who received autologous whole blood and nine patients who received irradiated allogeneic RBCs before incision (baseline), at the start and end of cardiopulmonary bypass, and at completion of surgery.

MEASUREMENTS AND MAIN RESULTS

The authors analyzed RBC deformability, erythrocyte indices, and density distribution to evaluate blood banking-induced alterations of autologous and allogeneic RBCs and changes in circulating RBCs in recipients, after blood transfusion. Time-dependent biochemical changes and significant decreases in deformability during storage occurred in both groups; however, homologous RBCs had significantly lower deformability than autologous RBCs. Trends in mean corpuscular volume and mean corpuscular hemoglobin concentration differed in both groups. In the homologous transfusion group, during cardiac surgery, RBC deformability, mean corpuscular volume, and mean corpuscular hemoglobin concentration showed significant changes compared with baseline values, and a greater number of denser subpopulations was observed at surgery completion.

CONCLUSIONS

Blood-processing techniques contribute to storage lesions, suggesting that transfusion of autologous whole blood, rather than allogeneic RBCs, could maintain the ability of circulating RBCs to deform and lead to potentially better transfusion outcomes.

Quantifying dynamic range in red blood cell energetics: Evidence of progressive energy failure during storage

BACKGROUND

During storage, red blood cells (RBCs) undergo significant biochemical and morphologic changes, referred to collectively as the "storage lesion". It was hypothesized that these defects may arise from disrupted oxygen-based regulation of RBC energy metabolism, with resultant depowering of intrinsic antioxidant systems.

STUDY DESIGN AND METHODS

As a function of storage duration, the dynamic range in RBC metabolic response to three models of biochemical oxidant stress (methylene blue, hypoxanthine/xanthine oxidase, and diamide) was assessed, comparing glycolytic flux by NMR and UHPLC-MS methodologies. Blood was processed/stored under standard conditions (AS-1 additive solution) with leukoreduction. Over a 6-week period, RBC metabolic and antioxidant status were assessed at baseline and following exposure to the three biochemical oxidant models. Comparison was made of glycolytic flux (¹ H-NMR tracking of [2-¹³ C]-glucose and metabolomic phenotyping with [1,2,3-¹³ C₃ ] glucose), reducing equivalent (NADPH/NADP⁺ ) recycling, and thiol-based (GSH/GSSG) antioxidant status.

RESULTS

As a function of storage duration, we observed the following: (1) a reduction in baseline hexose monophosphate pathway (HMP) flux, the sole pathway responsible for the regeneration of the essential reducing equivalent NADPH; with (2) diminished stress-based dynamic range in both overall glycolytic as well as proportional HMP flux. In addition, progressive with storage duration, RBCs showed (3) constraint in reducing equivalent (NADPH) recycling capacity, (4) loss of thiol based (GSH) recycling capacity, and (5) dysregulation of metabolon assembly at the cytoplasmic domain of Band 3 membrane protein (cdB3).

CONCLUSION

Blood storage disturbs normal RBC metabolic control, depowering antioxidant capacity and enhancing vulnerability to oxidative injury.

Red blood cell storage duration and peri-operative outcomes in paediatric cardiac surgery

BACKGROUND

Prior research on red blood cell (RBC) storage duration and clinical outcomes in paediatric cardiac surgery has shown conflicting results. The purpose of this study was to evaluate whether blood stored for a longer duration is harmful in these patients.

METHODS

We performed a retrospective cohort study of paediatric patients undergoing cardiac surgery at our institution between January 2011 and June 2015. Patients were stratified based on whether they were transfused RBCs stored for ≤15 days (fresher blood) or >15 days (older blood). The primary outcome was composite morbidity, with prolonged length of stay (LOS) as a secondary outcome. Subgroup analyses were performed after stratification by RBC transfusion volume (≤2 vs. >2 RBC units). Multivariable logistic regression models were used to assess the impact of RBC storage duration on composite morbidity and prolonged LOS.

RESULTS

Of 461 patients, 122 (26·5%) received fresher blood and 339 (73·5%) received older blood. The overall rate of composite morbidity was 18·0% (n = 22) for patients receiving fresher blood and 13·6% (n = 46) for patients receiving older blood (P = 0·24). In the risk-adjusted model, patients receiving older blood did not exhibit an increased risk of composite morbidity (OR: 0·74, 95% CI: 0·37-1·47, P = 0·40) or prolonged LOS (OR: 0·72, 95% CI: 0·38-1·35, P = 0·30) compared to patients receiving fresher blood. Similar results were seen after stratification by RBC transfusion volume.

CONCLUSIONS

Transfusing RBCs stored for a longer duration was not associated with an increased risk of morbidity or prolonged LOS in paediatric cardiac surgery patients.

Blood Utilization and Clinical Outcomes in Extracorporeal Membrane Oxygenation Patients

BACKGROUND

Patients requiring extracorporeal membrane oxygenation (ECMO) support are critically ill and have substantial transfusion requirements, which convey both risks and benefits. A retrospective analysis was conducted to assess the association between blood component administration and adverse outcomes in adult, pediatric, and neonatal ECMO patients.

METHODS

We evaluated 217 ECMO patients at a single center hospitalized between January 2009 and June 2016. Three cohorts (88 adult, 57 pediatric, and 72 neonatal patients) were included for assessment of patient characteristics, blood utilization, and clinical outcomes. Univariable and multivariable analyses were used to assess the association between transfusions and clinical outcomes (primary outcome: mortality and secondary outcomes: morbid events). The analysis included the main exposure of interest (total number of blood component units transfused) and potential confounding variables (age group cohort, case mix index, sex, ECMO mode and duration, and primary ECMO indication).

RESULTS

After adjustment for confounders, with each additional blood component unit transfused, there was an estimated increase in odds for mortality by 1% (odds ratio [OR] = 1.01; 95% confidence interval [CI], 1.00-1.02; P = .013) and an increase in odds for thrombotic events by 1% (OR = 1.01; 95% CI, 1.00-1.02; P = .007). Mortality was higher in the adult (57 of 88; 64.8%) and pediatric (37 of 57; 64.9%) than in the neonatal cohort (19 of 72; 26.4%) (P < .0001). Median total blood components transfused per day followed a similar pattern for the adult (2.3 units; interquartile range [IQR] = 0.8-7.0), pediatric (2.9 units; IQR = 1.1-10), and neonatal (1.0 units; IQR = 0.7-1.6) cohorts (P < .0001). Over the entire hospitalization, the total median blood components transfused was highest in the neonatal (41 units; IQR = 24-94) and pediatric (41 units; IQR = 17-113) compared to the adult (30 units; IQR = 9-58) cohort (P = .007). There was no significant interaction between total units transfused over the hospital stay and age cohort for mortality (P = .35).

CONCLUSIONS

Given the association between transfusion and adverse outcomes, effective blood management strategies may be beneficial in ECMO patients.

The dielectric spectroscopy of human red blood cells during 37-day storage: β-dispersion parameterization

This study exploits dielectric spectroscopy to monitor the kinetics of red blood cells (RBC) storage lesions, focusing on those processes linked to cellular membrane interface known as β-dispersion. The dielectric response of RBC suspensions, exposed to blood-bank cold storage for 37 days, was studied using time-domain dielectric spectroscopy in the frequency range 500 kHz to 200 MHz. The measured dielectric processes are characterized by their dielectric strength (Δε) and their relaxation times (τ). Changes in the dielectric properties of the RBC suspensions, due to storage-related biophysical changes, were evaluated. For a quantitative characterization of RBC vitality, we characterized the shape of fresh and stored RBC and measured their deformability as expressed by their average elongation ratio, which was achieved under a shear stress of 3.0 Pa. During the second week of storage, an increment in the evolution of the relaxation times and in the dielectric permittivity strength of about 25% was observed. We propose that the characteristic increment of ATP, during the second and third weeks of storage, is responsible for the raise of the specific capacitance of cell membrane, which in turn explains the changes observed in the dielectric response when combined with the influence of the shape changes.

Inter-donor variability in deformability of red blood cells in blood units

OBJECTIVE

This study aimed to examine the donor-to-donor variability in the deformability of red blood cells (RBCs) from freshly collected blood donations (F-RBC) and packed RBCs.

BACKGROUND

Packed RBCs are supplied for transfusion by the first-in-first-out (FIFO) criterion, assuming that their quality is the same for packed RBCs with equal storage duration. To challenge this notion, we determined the deformability of F-RBC and packed RBCs stored for different durations.

METHODS

Three RBC groups were employed: A. 79 samples of F-RBC; B. 76 samples of packed RBC units, randomly used for transfusion at different storage durations; and C. 65 samples of outdated packed RBCs stored for 35 to 37 days. All packed RBC units were non-leukofiltrated and stored in Citrate-phosphate-dextrose solution with adenine (CPDA-1). RBC deformability was determined using a computerised cell-flow properties analyser, which monitors the shape change of cells directly visualised in a narrow-gap flow chamber and provides the cells' deformability distribution in a large RBC population.

RESULTS

The F-RBC deformability exhibited a wide-range inter-donor variability. The cold storage of packed RBCs exerted a mild reduction of deformability, which became significant, compared to the initial inter-donor variability, only after 3 weeks of storage.

CONCLUSION

Packed RBCs are generally supplied for transfusion by the FIFO criterion based on the assumption that the storage duration is a key factor of RBC quality. This study demonstrates that the deformability of red blood cells is significantly different in donors, and substantial variability persists throughout the entire process of their storage. Therefore, the FIFO criterion is not sufficient for assessing the RBC deformability, which should, therefore, be specifically characterised for each unit.

Rapid thrombelastography predicts perioperative massive blood transfusion in patients undergoing coronary artery bypass grafting: A retrospective study

Massive blood transfusion (MBT) is a relatively common complication of cardiac surgery, which is independently associated with severe postoperative adverse events. However, the value of using rapid thrombotomography (r-TEG) to predict MBT in perioperative period of cardiac surgery has not been explored. This study aimed to identify the effect of r-TEG in predicting MBT for patients undergoing coronary artery bypass grafting (CABG).This retrospective study included consecutive patients first time undergoing CABG at the Zhongnan Hospital of Wuhan University between March 2015 and November 2017. All the patients had done r-TEG tests before surgery. The MBT was defined as receiving at least 4 units of red blood cells intra-operatively and 5 units postoperatively (1 unit red blood cells from 200 mL whole blood).Lower preoperative hemoglobin level (P = .001) and longer cardiopulmonary bypass time (P = .001) were the independent risk factors for MBT during surgery, and no components of the r-TEG predicted MBT during surgery. Meanwhile, longer activated clotting time (P < .001), less autologous blood transfusion (P = .001), and older age (P = .008) were the independent risk factors for MBT within 24 hours of surgery.Preoperative r-TEG activated clotting time can predict the increase of postoperative MBT in patients undergoing CABG. We recommend the careful monitoring of coagulation system with r-TEG, which allows rapid diagnosis of coagulation abnormalities even before the start of surgery.

Perioperative Transfusions and Venous Thromboembolism

BACKGROUND AND OBJECTIVES

Annual incidence of venous thromboembolism (VTE) including postoperative VTE in hospitalized children is rising significantly. A growing body of evidence supports the role of red blood cells (RBCs) in pathologic thrombosis. In this study, we examined the association of perioperative RBC transfusion with postoperative VTE in pediatric patients.

METHODS

The pediatric databases of the American College of Surgeons' National Surgical Quality Improvement Project from 2012 to 2017 were used. Multivariable logistic regression was used to examine the association between perioperative RBC transfusion status and the development of new or progressive VTE within 30 days of surgery. The analyses were age stratified, as follows: neonates (≤28 days), infants (>28 days and <1 year), and children (≥1 year).

RESULTS

In this study, we included 20 492 neonates, 79 744 infants, and 382 862 children. Postoperative development of VTE was reported in 99 (0.48%) neonates, 147 (0.2%) infants, and 374 (0.1%) children. In all age groups, development of VTE was significantly more common among patients with a perioperative RBC transfusion than patients without a perioperative RBC transfusion (neonates: adjusted odds ratio [aOR] = 4.1, 95% confidence interval [CI] = 2.5-6.7; infants: aOR = 2.4, 95% CI = 1.7-3.6; children: aOR = 2.2, 95% CI = 1.7-2.9). Among children who received an intra- or postoperative transfusion, the weight-based volume of RBCs (mL/kg) transfused was associated with postoperative VTE in a dose-dependent manner: second tertile (odds ratio = 2.3, 95% CI = 1.3-4.1) and third tertile (odds ratio = 4.1, 95% CI = 2.3-7.4) versus first tertile.

CONCLUSIONS

Perioperative RBC transfusions are independently associated with development of new or progressive postoperative VTE in children, infants, and neonates. These findings need further validation in prospective studies and emphasize the need for evidence-based perioperative pediatric blood transfusion decisions.

Vesiculation of Red Blood Cells in the Blood Bank: A Multi-Omics Approach towards Identification of Causes and Consequences

Microvesicle generation is an integral part of the aging process of red blood cells in vivo and in vitro. Extensive vesiculation impairs function and survival of red blood cells after transfusion, and microvesicles contribute to transfusion reactions. The triggers and mechanisms of microvesicle generation are largely unknown. In this study, we combined morphological, immunochemical, proteomic, lipidomic, and metabolomic analyses to obtain an integrated understanding of the mechanisms underlying microvesicle generation during the storage of red blood cell concentrates. Our data indicate that changes in membrane organization, triggered by altered protein conformation, constitute the main mechanism of vesiculation, and precede changes in lipid organization. The resulting selective accumulation of membrane components in microvesicles is accompanied by the recruitment of plasma proteins involved in inflammation and coagulation. Our data may serve as a basis for further dissection of the fundamental mechanisms of red blood cell aging and vesiculation, for identifying the cause-effect relationship between blood bank storage and transfusion complications, and for assessing the role of microvesicles in pathologies affecting red blood cells.

Storability of porcine blood in forensics: How far should we go?

Previous studies on the storability of porcine blood for bloodstain pattern analysis (BPA) focused on abattoir blood only and did not include measurements of viscoelasticity. Although known to provoke echinocyte formation, EDTA is widely used for BPA issues. We compared ageing samples taken from live pigs with abattoir blood and detected considerable differences in hematocrit (HCT), total protein and shear viscosity that even worsened with time. Upon storage, high shear viscosity continuously increased, resulting in a partial loss of the typical shear thinning property of blood. Furthermore, we explored CPDA-1, the gold standard in preserving red blood cells (RBCs), for storage of forensic samples. We found it to be a superior choice for anticoagulation, as the rise of high shear viscosity was attenuated compared to EDTA. When performing oscillation measurements, we found a sudden change of viscoelasticity of blood after 22 days, providing a cut-off for storage time. To highlight the importance of hematological and hemorheological changes upon cold storage, we performed simple drip pattern experiments. These tests revealed a tendency to smaller stain diameters and higher numbers of satellite spatter. While this contradicts expectations from elevated viscosity values, we associate this trend to microscopic inhomogeneities due to storage. We recommend CPDA-1 for prolonged storage of BPA samples and suggest the use of comprehensive test protocols including viscoelasticity for determination of the maximum shelf life of pig blood.

The Effect of Washing of Stored Red Blood Cell Transfusion Units on Post Transfusion Recovery and Outcome in a Pneumosepsis Animal Model

BACKGROUND

Septic patients are often anemic, requiring red blood cell (RBC) transfusions. However, RBC transfusions are associated with organ injury. The mechanisms of RBC-induced organ injury are unknown, but increased clearance of donor RBCs from the circulation with trapping in the organs could play a role. We hypothesized that washing of RBCs prior to transfusion may reduce clearance and trapping of donor cells and thereby reduce organ injury.

METHODS

Sprague-Dawley rats were inoculated intratracheally with 10 colony-forming units (CFU) of Streptococcus pneumoniae or vehicle as a control and transfused with either a washed or standard (non-washed) biotinylated RBC transfusion from syngeneic rats. Controls received saline. Blood samples were taken directly after transfusion and at 24 h to calculate the 24 h post transfusion recovery (PTR). After sacrifice, flow cytometry was used to detect donor RBCs in organs and blood. The organs were histologically scored by a pathologist and CFUs in the lung and blood were counted.

RESULTS

The 24h-PTR was similar between healthy and pneumoseptic rats after a standard transfusion. In healthy rats, a washed transfusion resulted in a higher PTR and less accumulation of donor RBCs in the organs compared with a standard transfusion. However, during pneumonia, this effect of washing was not seen. Transfusion did not further augment lung injury induced by pneumonia, but washing decreased bacterial outgrowth in the lungs associated with reduced lung injury.

CONCLUSION

In healthy recipients, washing increased 24h-PTR of donor RBCs and decreased trapping in organs. In pneumoseptic rats, washing reduced bacterial outgrowth and lung injury, but did not improve PTR.

Intra-operative blood transfusion significantly increases the risk of post-operative pulmonary embolism

Background

Pulmonary embolism (PE) is a serious and preventable complication after surgery. Blood transfusion is a common event during surgery. The aim of the present study was to identify whether intra-operative blood product transfusions increase the risk of symptomatic post-operative PE.

Methods

A retrospective, single-center case-control study at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University between 1 January 2013 and 31 December 2016 was performed. Adult hospitalized patients with confirmed symptomatic PE after surgery were defined as case group. Each patient was matched with two adult patients without symptomatic PE who underwent the same procedure on the same day or within one week. Perioperative data especially detailed blood transfusion was collected. Forward stepwise logistic regression analysis was performed.

Results

During the study period, altogether 188,512 procedures were included, and postoperative PE were confirmed in 40 (0.02%) patients. Twelve (30.0%) case patients and 16 (20.0%) control patients received intra-operative blood transfusion. Intra-operative blood transfusion was revealed as a significant predictor for symptomatic post-operative PE (OR 80.669, 95% CI: 3.312-1,964.641, P=0.007), along with female sex (OR 86.921, 95% CI: 4.242-1,781.124, P=0.004), older age (OR 1.078, 95% CI: 1.005-1.156, P=0.035), longer length of stay before surgery (OR 1.124, 95% CI: 1.040-1.214, P=0.003) and longer operation time (OR 1.013, 95% CI: 1.002-1.025, P=0.024).

Conclusions

Intra-operative blood transfusion was associated with an increased risk of symptomatic post-operative PE. PE prophylaxis and selective screening should be considered in patients who had received intra-operative blood transfusion, especially in female patients.

Effects of L-carnitine on the erythrocytes of stored human blood

OBJECTIVES

This study aimed to assess the effects of L-carnitine on oxidative stress in human erythrocytes during storage.

BACKGROUND

Using antioxidants as components of blood storage solutions may combat the effects of storage-induced oxidative stress on erythrocytes.

METHODS

Blood from male adults was stored at 4 °C for 55 days in citrate phosphate dextrose adenine solution, without L-carnitine (Control) and with L-carnitine as an additive (at concentrations of 10, 30 and 60 mM - Experiments). Every fifth day, erythrocyte markers (morphology, count, haemoglobin, haemolysis and osmotic fragility), antioxidant defences (antioxidant enzymes and total antioxidant capacity) and oxidative stress markers (superoxides, lipid peroxidation and protein oxidation products) were analysed.

RESULTS

Oxidative damage was observed in controls (day 25 onwards) and in experiments (day 35 onwards). L-carnitine (10 and 30 mM) protected erythrocytes from damage up to day 35 by maintaining haemoglobin and lipid peroxidation, assisting antioxidant enzymes and increasing antioxidant capacity by elevating sulfhydryls and ascorbic acid. L-carnitine was beneficial in prolonging storage up to 55 days but could not prevent oxidative damage completely in terms of haemolysis and osmotic fragility.

CONCLUSIONS

L-carnitine ameliorated oxidative stress, but combinations with other antioxidants may provide comprehensive protection to erythrocytes during storage.

Intraoperative cell salvage: A technology built upon the failures, fads and fashions of blood transfusion

Transfusion, as we know it today, developed into a very sophisticated treatment modality as a result of centuries of experimentation. Intraoperative cell salvage is a transfusion technique where autologous blood lost during surgery is reinfused. The success of this process relies on specialised equipment and techniques to collect, process, anticoagulate filter and reinfuse blood. Through a literature review, we collected information about the early origins of specific techniques relevant to intraoperative cell salvage: the ability to collect lost blood, to prevent collected blood from clotting, to remove debris through processing and other harmful aspects through filtering, the benefits of autologous blood transfusion, reinfusion and traditional concerns and contraindications. A culmination of knowledge specific to each of these techniques over centuries provides the background to the safe intraoperative cell salvage technique used today. In addition, we aimed to identify the reasons why specific equipment and techniques developed, why practice changed and what is still unknown. This article reviews relevant allogeneic transfusion and autotransfusion history, starting in Roman times, and includes landmark events through the centuries.

Optofluidic laser speckle image decorrelation analysis for the assessment of red blood cell storage

Red blood cells (RBCs) undergo irreversible biochemical and morphological changes during storage, contributing to the hemorheological changes of stored RBCs, which causes deterioration of microvascular perfusion in vivo. In this study, a home-built optofluidic system for laser speckle imaging of flowing stored RBCs through a transparent microfluidic channel was employed. The speckle decorrelation time (SDT) provides a quantitative measure of RBC changes, including aggregation in the microchannel. The SDT and relative light transmission intensity of the stored RBCs were monitored for 42 days. In addition, correlations between the decorrelation time, RBC flow speed through the channel, and relative light transmission intensity were obtained. The SDT of stored RBCs increased as the storage duration increased. The SDTs of the RBCs stored for 21 days did not significantly change. However, for the RBCs stored for over 35 days, the SDT increased significantly from 1.26 ± 0.27 ms to 6.12 ± 1.98 ms. In addition, we measured the relative light transmission intensity and RBC flow speed. As the RBC storage time increased, the relative light transmission intensity increased, whereas the RBC flow speed decreased in the microchannel. The optofluidic laser speckle image decorrelation time provides a quantitative measure of assessing the RBC condition during storage. Laser speckle image decorrelation analysis may serve as a convenient assay to monitor the property changes of stored RBCs.

The impact of patient blood management on blood utilization and clinical outcomes in complex spine surgery

BACKGROUND

Patient blood management (PBM) is especially applicable in major spine surgery, during which bleeding and transfusion are common. What remains unclear in this setting is the overall impact of bundled PBM measures on transfusion requirements and clinical outcomes. We compared these outcomes before and after implementing a PBM program.

STUDY DESIGN AND METHODS

We conducted a retrospective review of 928 adult complex spine surgery patients performed by a single surgeon between January 2009 and June 2016. Although PBM measures were phased in over time, tranexamic acid (TXA) administration became standard protocol in July 2013, which defined our pre- and post-PBM periods. Transfusion rates for all blood components before and after PBM implementation were compared, as were morbid event rates and mortality.

RESULTS

Baseline characteristics were similar before and after PBM. Before PBM, the mean number of units/patient decreased for red blood cells (RBCs; by 19.5%; p = 0.0057) and plasma (by 33%; p = 0.0008), but not for platelets (p = 0.15). After risk adjustment by multivariable analyses, the composite outcome of morbidity or mortality showed a nonsignificant trend toward improvement after PBM (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.39-1.01; p = 0.055), and the risk of thrombotic events was unchanged (OR, 1.12; 95% CI, 0.42-2.58; p = 0.80).

CONCLUSION

In complex spine surgery, a multifaceted PBM program that includes TXA can be advantageous by reducing transfusion requirements without changing clinical outcomes.

Quantitative Characteristics of Toxic Compounds According to the Solvent Type

The quantitative analysis of target substances is an important part of assessing the toxicity of diverse materials. Usually, the quantitation of target compounds is conducted by instrumental analysis such as chromatography and capillary electrophoresis. If solvents are used in the pretreatment step of the target analyte quantification, it would be crucial to examine the solvent effect on the quantitative analysis. Therefore, in this study, we assessed the solvent effects using four different solvents (methanol, hexane, phosphate buffered saline (PBS), and dimethyl sulfoxide (DMSO)) and three toxic compounds (benzene, toluene, and methylisothiazolinone (MIT)). Liquid working standards containing the toxic compounds were prepared by dilution with each solvent and analyzed by gas chromatography-mass spectrometry (GC-MS). As a result, we found that the response factor (RF) values of the target analytes were different, depending on the solvent types. In particular, benzene and toluene exhibited their highest RF values (33,674 ng^-1 and 78,604 ng^-1, respectively) in hexane, while the RF value of MIT was the highest (9,067 ng^-1) in PBS. Considering the correlation (R ²) and relative standard deviation (RSD) values, all target analytes showed fairly good values (R ² > 0.99 and RSD < 10%) in methanol and DMSO. In contrast, low R ² (0.0562) and high RSD (10.6%) values of MIT were detected in hexane, while benzene and toluene exhibited relatively low R ² and high RSD values in PBS (mean R ² = 0.9892 ± 0.0146 and mean RSD = 13.3 ± 4.1%). Based on these findings, we concluded that the results and reliability of the quantitative analysis change depending on the analyte and solvent types. Therefore, in order to accurately assess the toxicity of target compounds, reliable analytical data should be obtained, preferentially by considering the solvent types.

Transfusion of Red Blood Cells Stored More Than 28 Days is Associated With Increased Morbidity Following Spine Surgery

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study was to describe the association between storage duration of packed red blood cells (PRBCs) and perioperative adverse events in patients undergoing spine surgery at a tertiary care center.

SUMMARY OF BACKGROUND DATA

Despite retrospective studies that have shown that longer PRBC storage duration worsens patient outcomes, randomized clinical trials have found no difference in outcomes. However, no studies have examined the impact of giving the oldest blood (28 days old or more) on morbidity within spine surgery.

METHODS

The surgical administrative database at our institution was queried for patients transfused with PRBCs who underwent spine surgery between December 4, 2008, and June 26, 2015. Patients undergoing spinal fusion, tumor-related surgeries, and other identified spine surgeries were included. Patients were divided into two groups on the basis of storage duration of blood transfused: exclusively ≤28 days' storage or exclusively >28 days' storage. The primary outcome was composite in-hospital morbidity, which included (1) infection, (2) thrombotic event, (3) renal injury, (4) respiratory event, and/or (5) ischemic event.

RESULTS

In total, 1141 patients who received a transfusion were included for analysis in this retrospective study; 710 were transfused exclusively with PRBCs ≤28 days' storage and 431 exclusively with PRBCs >28 days' storage. Perioperative complications occurred in 119 patients (10.4%). Patients who received blood stored for >28 days had higher odds of developing any one complication [odds ratio (OR) = 1.82; 95% confidence interval (95% CI), 1.20-2.74; P = 0.005] even after adjusting for competing perioperative risk factors.

CONCLUSION

Blood stored for >28 days is independently associated with higher odds of developing perioperative complications in patients transfused during spinal surgery. Our results suggest that blood storage duration may be an appropriate parameter to consider when developing institutional transfusion guidelines that seek to optimize patient outcomes.

LEVEL OF EVIDENCE

3.

Quality Initiative Programs Can Decrease Total Joint Arthroplasty Transfusion Rates-A Multicenter Study Using the MARCQI Total Joint Registry Database

BACKGROUND

The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) noted wide variability between member hospitals in blood transfusion rates after primary total hip and knee arthroplasty (THA and TKA). Blood transfusion has substantial risks and accepted recommendations exist to guide transfusion practices. MARCQI began an initiative to decrease unnecessary transfusions by identifying/reporting outliers, discussing conservative transfusion practices, and recommending transfusion guidelines. There was a later recommendation to consider intraoperative use of tranexamic acid.

METHODS

All MARCQI-registered unilateral TKA and THA cases from the 28 member hospitals (pre-November 2013) were included. For 3 time periods (before November 13, 2013; November 13, 2013, to November 12, 2014; and after November 12, 2014), we calculated average risk and range of transfusion, transfusion with nadir hemoglobin >8 g/dL, mean length of stay, and 90-day risk of discharge to nursing home, readmission, deep infection, and emergency department visits.

RESULTS

For THA, risk and range of transfusion decreased over the 3 time periods: 12.6% (2.5%-36.2%), 7.6% (2.2%-23.8%), and 4.5% (0.7%-14.4%); for TKA, 6.3% (1.3%-15.6%), 3.1% (0%-12.5%), and 1.3% (0%-7.4%). Decreases were also noted for transfusion with a nadir hemoglobin >8 g/dL with a near elimination of "unnecessary" transfusions. There was no evidence of increase in length of stay, discharge to nursing home, readmission, deep infection, or emergency department visits.

CONCLUSION

A simple intervention can decrease unnecessary blood transfusions during and after elective primary unilateral THA or TKA. A collaborative registry can be used effectively to improve the quality of patient care and set a new benchmark for transfusion.

Transfusion Decision Making in Pediatric Critical Illness

Transfusion decision making (TDM) in the critically ill requires consideration of: (1) anemia tolerance, which is linked to active pathology and to physiologic reserve, (2) differences in donor RBC physiology from that of native RBCs, and (3) relative risk from anemia-attributable oxygen delivery failure vs hazards of transfusion, itself. Current approaches to TDM (e.g. hemoglobin thresholds) do not: (1) differentiate between patients with similar anemia, but dissimilar pathology/physiology, and (2) guide transfusion timing and amount to efficacy-based goals (other than resolution of hemoglobin thresholds). Here, we explore approaches to TDM that address the above gaps.

Impact of Preoperative Anemia and Postoperative Hemoglobin Drop on the Incidence of Acute Kidney Injury and In-Hospital Mortality in Patients With Type B Acute Aortic Syndromes Undergoing Thoracic Endovascular Aortic Repair

BACKGROUND

The impact of preoperative anemia and postoperative hemoglobin (Hb) drop on the incidence of acute kidney injury (AKI) after thoracic endovascular aortic repair (TEVAR) for type B acute aortic syndromes (AAS) as well as their prognostic value is unknown.

METHODS

This retrospective study included 144 patients with type B AAS undergoing TEVAR at our center. Preoperative anemia was classified as no/mild (Hb ≥ 12.0 g/dL in men; ≥11.3 g/dL in women), moderate (Hb 10.80-11.99 g/dL in men; 10.23-11.29 g/dL in women), and severe (<10.80 g/dL in men; <10.23 g/dL in women). Postoperative Hb drop was classified as mild (<2 g/dL), moderate (2-4 g/dL), and severe (>4 g/dL). End points of the study were postoperative AKI and in-hospital mortality.

RESULTS

Postoperative AKI was higher in the severe and moderate anemia groups than the no/mild anemia group (63.2%, 52.0%, and 31.0%, respectively, P = .01). In-hospital mortality and AKI were higher in patients with severe postoperative Hb drop (40.9% and 86.4%) than patients with moderate (6.9% and 36.2%) and mild (4.7% and 25.0%) postoperative Hb drop (both P < .001). Postoperative Hb drop (odds ratio [OR]:1.67, P = .036), postoperative Hb levels (OR: 0.57, P = .025), and mesenteric ischemia (OR: 4.65, P = .044) were identified as independent predictors of in-hospital mortality. Preoperative Hb (OR: 0.26, P = .001), postoperative Hb drop (OR: 4.34, P < .001), contrast medium (OR: 1.82, P = .004), and diabetes mellitus (OR: 3.79, P = .001) were independent predictors of AKI. At follow-up, anemia and postoperative Hb drop were not associated with increased mortality.

CONCLUSION

Preoperative Hb and postoperative Hb drop were significant risk factors for AKI. Postoperative Hb drop and Hb levels predicted in-hospital mortality.

Thrombotic and Infectious Morbidity Are Associated with Transfusion in Posterior Spine Fusion

BACKGROUND

Although previous investigators have established an association between blood transfusion and adverse outcomes, the relative frequency of different morbid events and the association with transfusion dose are not well understood.

QUESTIONS/PURPOSES

The purpose of the study is to characterize the relationship between blood transfusion and different types of morbidity after posterior spine fusion.

METHODS

We retrospectively analyzed electronic medical records for 963 patients who underwent posterior spinal fusion surgery at a single institution, of which 603 (62.6%) received an allogeneic blood transfusion. Then, we assessed patient and surgical characteristics in a risk-adjusted fashion to identify various morbid event rates and independent predictors in these adverse outcomes.

RESULTS

Compared to the non-transfused patients, transfused patients had a higher incidence of any morbid event (9.1 vs. 2.5%. P < 0.0001), thrombotic events (4.6 vs. 1.1%, P = 0.0025), and hospital-acquired infections (2.3 vs. 0.6%, P = 0.039). Renal, respiratory, and ischemic morbidity occurred less frequently and were not more common in transfused patients. Risk-adjusted analysis revealed a dose-response effect, whereby for each unit of allogeneic blood transfused, the risks of any morbid event (OR 1.183; 95% CI 1.103-1.274; P < 0.0001), thrombotic complication (OR 1.104; 95% CI 1.032-1.194; P = 0.0035), and infectious complication (OR 1.182; 95% CI 1.077-1.332; P = 0.0002) were increased.

CONCLUSION

Our data demonstrate risk-adjusted and transfusion dose-related increases in perioperative morbidity, with thrombotic and infectious events being the most common.

Dielectric Response of Cytoplasmic Water and Its Connection to the Vitality of Human Red Blood Cells. II. The Influence of Storage

Maintaining an appropriate inventory of packaged blood products is a critical part of modern medicine. Consequently, the assessment of red blood cell (RBC) functionality is instrumental for the monitoring of the quality of stored RBC (sRBC) in the blood bank. We present a comprehensive study of sRBC lesion kinetics in SAGM (saline, adenine, glucose, mannitol) solution, using microwave dielectric spectroscopy (0.5-50 GHz) and cell deformability. As part of the research, we have isolated the microwave dielectric response of cytoplasmic water in sRBC. The extracted dielectric parameters are sensitive to the age of the cells and, in particular, to the critical moment of transition from discocyte to echinocyte. From the analysis of the dielectric relaxation as a function of storage-duration, we postulate that the behavior is rooted in the delicate interplay between bound and bulk water in the cellular interior. In particular, the microwave dielectric response reflects the moment when the continuous diffusion of oxygen to the cell and the oxygenation of hemoglobin affects the role played by water in the maintenance of cell integrity. These results open a possible new avenue for the noninvasive inspection of stored red blood cells, permitting a true inventory system for the modern blood bank.

Decrease in red blood cell deformability is associated with a reduction in RBC-NOS activation during storage

During storage, red blood cells (RBC) become more susceptible to hemolysis and it has also been shown that RBC deformability, which is influenced by RBC nitric oxide synthase (RBC-NOS) activity, decreases during blood storage while a correlation between these two parameters under storage conditions has not been investigated so far. Therefore, blood from 15 male volunteers was anticoagulated, leuko-reduced and stored as either concentrated RBC or RBC diluted in saline-adenine-glucose-mannitol (SAGM) for eight weeks at 4°C and results were compared to data obtained from freshly drawn blood. During storage, decrease of RBC deformability was related to increased mean cellular volume and increased cell lysis but also to a decrease in RBC-NOS activation. The changes were more pronounced in concentrated RBC than in RBC diluted in SAGM suggesting that the storage method affects the quality of blood. These data shed new light on mechanisms underlying the phenomenon of storage lesion and reveal that RBC-NOS activation and possibly nitric oxide production in RBC are key elements that are influenced by storage and in turn alter deformability. Further studies should therefore also focus on improving these parameters during storage to improve the quality of stored blood with respect to blood transfusion.

Quality Assessment of Established and Emerging Blood Components for Transfusion

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation.

Outcomes following operative vs. non-operative management of blunt traumatic pancreatic injuries: a retrospective multi-institutional study

Background

Traumatic pancreatic injuries are rare, and guidelines specifying management are controversial and difficult to apply in the acute clinical setting. Due to sparse data on these injuries, we carried out a retrospective review to determine outcomes following surgical or non-surgical management of traumatic pancreatic injuries. We hypothesize a higher morbidity and mortality rate in patients treated surgically when compared to patients treated non-surgically.

Methods

We performed a retrospective review of data from four trauma centers in New York from 1990–2014, comparing patients who had blunt traumatic pancreatic injuries who were managed operatively to those managed non-operatively. We compared continuous variables using the Mann-Whitney U test and categorical variables using the chi-square and Fisher’s exact tests. Univariate analysis was performed to determine the possible confounding factors associated with mortality in both treatment groups.

Results

Twenty nine patients were managed operatively and 32 non-operatively. There was a significant difference between the operative and non-operative groups in median age (37.0 vs. 16.2 years, P = 0.016), grade of pancreatic injury (grade I; 30.8 vs. 85.2%, P value for all comparisons <0.0001), median injury severity score (ISS) (16.0 vs. 4.0, P = 0.002), blood transfusion (55.2 vs. 15.6%, P = 0.0012), other abdominal injuries (79.3 vs. 38.7%, P = 0.0014), pelvic fractures (17.2 vs. 0.00%, P = 0.020), intensive care unit (ICU) admission (86.2 vs. 50.0%, P = 0.003), median length of stay (LOS) (16.0 vs. 4.0 days, P <0.0001), and mortality (27.6 vs. 3.1%, P = 0.010).

Conclusions

Patients with traumatic pancreatic injuries treated operatively were more severely injured and suffered greater complications than those treated non-operatively. The greater morbidity and mortality associated with these patients warrants further study to determine optimal triage strategies and which subset of patients is likely to benefit from surgery.

Pretransfusion Comparison of Dialyser-Based Hemoconcentrator With Cell Saver System for Perioperative Cell Salvage

OBJECTIVE

Cell Saver system is the method of choice for red blood cell salvage from the surgical field; however, cost is a limiting factor. We at our institute have devised a cost-effective version of dialyser-based autotransfusion system. We performed pretransfusion comparison of our autotransfusion system with conventional cell saver system.

METHODS

A prospective randomized observational study was performed in 104 consecutive patients with coronary artery disease undergoing by off-pump coronary artery bypass grafting. Patients were divided into two groups. In the dialyser group (53 patients), blood from surgical field was salvaged by our dialyser-based system. In the cell saver group (51 patients), blood was salvaged by cell saver. In both groups, 20-mL sample from the salvaged blood was analyzed for hemoglobin, platelets, protein, albumin, free hemoglobin, osmotic fragility, and peripheral blood smear examination.

RESULTS

Total hemoglobin salvaged was comparable in both groups (85% vs 76%). On peripheral smear, red blood cells were swollen, but morphology was preserved. Moreover, normal osmotic fragility suggested absence of any lethal damage to red blood cells in either group. Dialyser-based system was more efficient in salvaging platelets (42.9% vs 6%), proteins (79.2% vs 0%), and albumin (65% vs 0%). Total free hemoglobin was three times more in dialyser group but was well below recommended limits.

CONCLUSIONS

Dialyser-based system is economical, is equally efficacious in salvaging red blood cells, is more effective in salvaging platelets and proteins, and does not contain significant amount of free hemoglobin. Therefore, this salvaged blood can be safely transfused.

Blood Transfusion and the Risk of Acute Kidney Injury Among Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

Background—

Acute kidney injury (AKI) complicating percutaneous coronary intervention (PCI) is associated with adverse clinical outcomes. To date, no studies have evaluated the association of blood transfusion with AKI in patients undergoing PCI.

Methods and Results—

We used a retrospective cohort study of all patients with acute coronary syndrome undergoing PCI from CathPCI Registry (n=1 756 864). The primary outcome was AKI defined as the rise in serum creatinine post procedure ≥0.5 mg/dL or ≥25% above baseline values. AKI developed in 9.0% of study sample. Patients with AKI were older, more often women, and had high prevalence of comorbidities, including diabetes mellitus, hypertension, and advanced stages of chronic kidney disease at baseline. Blood transfusion was utilized in 2.2% of patients. In the overall sample, AKI developed in 35.1% of patients who received transfusion versus 8.4% of patients without transfusion (adjusted odds ratio, 4.87 [4.71–5.04]). In the subgroup of patients who sustained bleeding event and received transfusion, the rate of AKI was significantly increased across all preprocedure hemoglobin levels versus no blood transfusion. Similar findings were seen in the subgroup of patients with no bleeding event.

Conclusions—

Blood transfusion is strongly associated with AKI in patients with acute coronary syndrome undergoing PCI. Further investigation is needed to determine whether a restrictive blood transfusion strategy might improve PCI outcomes by reducing the risk of AKI.

Transfusion of Blood Products Affects Outcome in Cardiac Surgery

There remains controversy as to when patients undergoing cardiac surgery should receive a transfusion and whether a low hematocrit and its treatment with a transfusion of red cells influences outcome. The data related to this controversy are reviewed. Although the risk of known viral transmission is currently low, stored red cells do not function normally, and each unit contains activated inflammatory cells and mediators. These changes cause limited oxygen release, impaired microcirculatory flow, and immune suppression. A number of studies have observed decreased survival associated with transfusions in trauma, coronary artery bypass grafting, and intensive care unit patients. Studies that show an adverse outcome associated with low hematocrit are not definitive, because they fail to distinguish between the impact of low hematocrit per se and the possible adverse effects of transfusion, for what the low hematocrit may simply be a surrogate. The observation that a low hematocrit is associated with an adverse outcome does not necessarily prove that “treatment” of the anemia with a red cell transfusion will improve the outcome. Stored platelets contain a highly activated mixture of platelets with storage lesions and inflammatory mediators. Two retrospective post hoc multifactorial analyses suggest that platelet transfusions are associated with substantial increased morbidity and mortality. Clearly, large prospective studies are required to define the proper trigger for blood product transfusion to balance the adverse effects of anemia and platelet deficiency or dysfunction with the adverse effects of transfusion of blood products on morbidity and mortality associated with cardiac surgery and anesthesia.

Haptoglobin or Hemopexin Therapy Prevents Acute Adverse Effects of Resuscitation After Prolonged Storage of Red Cells

BACKGROUND

Extracellular hemoglobin and cell-free heme are toxic breakdown products of hemolyzed erythrocytes. Mammals synthesize the scavenger proteins haptoglobin and hemopexin, which bind extracellular hemoglobin and heme, respectively. Transfusion of packed red blood cells is a lifesaving therapy for patients with hemorrhagic shock. Because erythrocytes undergo progressive deleterious morphological and biochemical changes during storage, transfusion of packed red blood cells that have been stored for prolonged intervals (SRBCs; stored for 35-40 days in humans or 14 days in mice) increases plasma levels of cell-free hemoglobin and heme. Therefore, in patients with hemorrhagic shock, perfusion-sensitive organs such as the kidneys are challenged not only by hypoperfusion but also by the high concentrations of plasma hemoglobin and heme that are associated with the transfusion of SRBCs.

METHODS

To test whether treatment with exogenous human haptoglobin or hemopexin can ameliorate adverse effects of resuscitation with SRBCs after 2 hours of hemorrhagic shock, mice that received SRBCs were given a coinfusion of haptoglobin, hemopexin, or albumin.

RESULTS

Treatment with haptoglobin or hemopexin but not albumin improved the survival rate and attenuated SRBC-induced inflammation. Treatment with haptoglobin retained free hemoglobin in the plasma and prevented SRBC-induced hemoglobinuria and kidney injury. In mice resuscitated with fresh packed red blood cells, treatment with haptoglobin, hemopexin, or albumin did not cause harmful effects.

CONCLUSIONS

In mice, the adverse effects of transfusion with SRBCs after hemorrhagic shock are ameliorated by treatment with either haptoglobin or hemopexin. Haptoglobin infusion prevents kidney injury associated with high plasma hemoglobin concentrations after resuscitation with SRBCs. Treatment with the naturally occurring human plasma proteins haptoglobin or hemopexin may have beneficial effects in conditions of severe hemolysis after prolonged hypotension.

Donor-variation effect on red blood cell storage lesion: A close relationship emerges

Although the molecular pathways leading to the progressive deterioration of stored red blood cells (RBC storage lesion) and the clinical relevance of storage-induced changes remain uncertain, substantial donor-specific variability in RBC performance during storage, and posttransfusion has been established ("donor-variation effect"). In-bag hemolysis and numerous properties of the RBC units that may affect transfusion efficacy have proved to be strongly donor-specific. Donor-variation effect may lead to the production of highly unequal blood labile products even when similar storage strategy and duration are applied. Genetic, undiagnosed/subclinical medical conditions and lifestyle factors that affect RBC characteristics at baseline, including RBC lifespan, energy metabolism, and sensitivity to oxidative stress, are all likely to influence the storage capacity of individual donors' cells, although not evident by the donor's health or hematological status at blood donation. Consequently, baseline characteristics of the donors, such as membrane peroxiredoxin-2 and serum uric acid concentration, have been proposed as candidate biomarkers of storage quality. This review article focuses on specific factors that might contribute to the donor-variation effect and emphasizes the emerging need for using omics-based technologies in association with in vitro and in vivo transfusion models and clinical trials to discover biomarkers of storage quality and posttransfusion recovery in donor blood.

Proteomics of the red blood cell carbonylome during blood banking of erythrocyte concentrates

PURPOSE

Transfusion of red blood cells (RBCs) is a daily medical procedure. Erythrocyte concentrates (ECs) can be stored up to 56 days at 4 °C in saline additive solution mainly composed of adenine and sugar. Such nonphysiological conditions induce the occurrence of storage lesions, such as alterations of metabolism, protein oxidation, and deterioration of rheological properties. Their accumulation tends to decrease the main EC therapeutic property, that is, the oxygenation capacity. Protein carbonylation is a marker of oxidative stress and aging, and its occurrence during RBC storage was earlier characterized as a time-dependent and cellular compartment dependent modification.

EXPERIMENTAL DESIGN

Three ECs from independent donations were followed. The carbolynome was here characterized in soluble and membrane extracts (n-dodecyl β-D-maltoside-based extraction buffer) of RBCs stored for 6, 27, and 41 days, through biotin hydrazide derivatization, biotin-avidin affinity purification, SDS-PAGE separation, and LC-MS/MS analyses.

RESULTS

A total of 142 and 20 proteins were identified as carbonylated in soluble and membrane extracts, respectively. Particularly, a time-dependent evolution of 26.8% of the soluble carbonylome was observed.

CONCLUSIONS AND CLINICAL RELEVANCE

Affected cellular mechanisms involve antioxidant defenses, metabolism pathways, and proteasomal degradation. To better store RBCs those functions have to be preserved, which opens new routes of investigation in transfusion medicine.