Impact of technical and assay variation on reporting of hemolysis in stored red blood cell products

Priorities for Clinical Research in Pediatric Extracorporeal Membrane Oxygenation Anticoagulation From the Pediatric Extracorporeal Membrane Oxygenation Anticoagulation CollaborativE Consensus Conference

OBJECTIVES

To identify and prioritize research questions for anticoagulation and hemostasis management of neonates and children supported with extracorporeal membrane oxygenation (ECMO) from the Pediatric ECMO Anticoagulation CollaborativE (PEACE) consensus.

DATA SOURCES

Systematic review was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021, followed by serial consensus conferences of international, interprofessional experts in the management of ECMO for critically ill neonates and children.

STUDY SELECTION

The management of ECMO anticoagulation for critically ill neonates and children.

DATA EXTRACTION

Within each of the eight subgroups, two authors reviewed all citations independently, with a third independent reviewer resolving any conflicts.

DATA SYNTHESIS

Following the systematic review of MEDLINE, EMBASE, and Cochrane Library databases from January 1988 to May 2021, and the consensus process for clinical recommendations and consensus statements, PEACE panel experts constructed research priorities using the Child Health and Nutrition Research Initiative methodology. Twenty research topics were prioritized, falling within five domains (definitions and outcomes, therapeutics, anticoagulant monitoring, protocolized management, and impact of the ECMO circuit and its components on hemostasis).

CONCLUSIONS

We present the research priorities identified by the PEACE expert panel after a systematic review of existing evidence informing clinical care of neonates and children managed with ECMO. More research is required within the five identified domains to ultimately inform and improve the care of this vulnerable population.

Dexamethasone-Loaded Ureasil Hydrophobic Membrane for Bone Guided Regeneration

Physical barrier membranes have been used to release active substances to treat critical bone defects; however, hydrophilic membranes do not present a prolonged release capacity. In this sense, hydrophobic membranes have been tested. Thus, this study aimed to develop hydrophobic membranes based on mixtures of ureasil-polyether-type materials containing incorporated dexamethasone (DMA) for the application in guided bone regeneration. The physicochemical characterization and biological assays were carried out using small-angle X-ray scattering (SAXS), an in vitro DMA release study, atomic force microscopy (AFM), a hemolysis test, and in vivo bone formation. The swelling degree, SAXS, and release results revealed that the u-PPO400/2000 membrane in the proportion of 70:30 showed swelling (4.69% ± 0.22) similar to the proportions 90:10 and 80:20, and lower than the proportion 60:40 (6.38% ± 0.49); however, an equal release percentage after 134 h was observed between the proportions 70:30 and 60:40. All u-PPO materials presented hemocompatibility (hemolysis ≤2.8%). AFM results showed that the treatments with or without DMA did not present significant differences, revealing a flat/smooth surface, with no pores and/or crystalline precipitates. Finally, in vivo results revealed that for both the commercial hydrophilic membrane and u-PPO400/2000 (70:30) after 60 days, the bone formation volume was 21%. In conclusion, hybrid membranes present unique characteristics for treating critical bone defects, considering the delayed and prolonged release results associated with the physical barrier capacity.

Intraoperative Allogeneic Red Blood Cell Transfusion Negatively Influences Prognosis After Radical Surgery for Pancreatic Cancer: A Propensity Score Matching Analysis

OBJECTIVE

We aimed to investigate the real impact of allogeneic red blood cell transfusion (ABT) on postoperative outcomes in resectable pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

Of 128 patients undergoing resectable PDAC surgery at our facility, 24 (18.8%) received ABT. Recurrence-free survival (RFS) and disease-specific survival (DSS), before and after propensity score matching (PSM), were compared among patients who did and did not receive ABT.

RESULTS

In the entire cohort, ABT was significantly associated with decreased RFS (P = 0.002) and DSS (P = 0.014) before PSM. Cox regression analysis identified ABT (risk ratio, 1.884; 95% confidence interval, 1.015-3.497; P = 0.045) as an independent prognostic factor for RFS. Univariate and multivariate analysis identified preoperative hemoglobin value, preoperative total bilirubin value, and intraoperative blood loss as significant independent risk factors for ABT. Using these 3 variables, PSM analysis created 16 pairs of patients. After PSM, the ABT group had significantly poorer RFS rates than the non-ABT group (median, 9.8 vs 15.8 months, P = 0.022). Similar tendencies were found in DSS rates (median, 19.4 vs 40.0 months, P = 0.071).

CONCLUSIONS

This study revealed certain negative effects of intraoperative ABT on postoperative survival outcomes in patients with resectable PDAC.

An Antioxidant Nanoparticle Enhances Exercise Performance in Rat High-intensity Running Models

Although the adverse effects of excessively generated reactive oxygen species (ROS) on the body during aerobic exercise have been debated, there are few reports on the remarkable effects of the application of conventional antioxidants on exercise performance. The conventional antioxidants could not enhance exercise performance due to their rapid excretion from the body and serious adverse effects on the cellular respiratory system. In this study, impact of the original antioxidant self-assembling nanoparticle, redox-active nanoparticle (RNP), is investigated on the exercise performance of rats during running experiments. With an increase in the dose of the administered RNP, the all-out time of the rat running extends in a dose-dependent manner. In contrast, with an increase in the dose of the low-molecular-weight (LMW) antioxidant, the all-out running time of the rats decreases. The control group and LMW antioxidant treated group decrease in the number of red blood cells (RBCs) and increase oxidative stress after running. However, the RNP group maintains a similar RBC level and oxidative stress as that of the sedentary group. The results suggest that RNP, which shows long-blood circulation without disturbance of mitohormesis, effectively removes ROS from the bloodstream to suppresses RBC oxidative stress and damage, thus improving exercise performance.

Impact of different syringe pumps on red cells during paediatric simulated transfusion

BACKGROUND

Critically ill patients frequently need blood transfusions. For safety, blood must be delivered via syringe infusion pumps, yet this can cause red cell damage and increase the rate of haemolysis.

AIMS AND OBJECTIVES

To evaluate biochemical and haemolytic markers of red blood cells transfused in three different types of syringe infusion pumps at two different infusion rates (10 and 100 mL/h).

DESIGN AND METHODS

A lab-based study using aliquots of 16 red blood cell bags was undertaken. Haemolysis markers (total haemoglobin [g/dL], haematocrit [%], free haemoglobin [g/dL], potassium [mmol/L], lactate dehydrogenase [U/L], osmolality [mOsm/kg], pH, degree of haemolysis [%]) were measured before and after red blood cell infusion and exposure. Three different syringe infusion pumps brands (A, B, and C) were compared at two different infusion rates (10 and 100 mL/h).

RESULTS

Total haemoglobin fell significantly in all red blood cell units during manipulation (pre-infusion: 26.44 ± 5.74; post-exposure: 22.62 ± 4.00; P = .026). The degree of haemolysis significantly increased by 40% after manipulation of the red blood cells. Syringe infusion pump A caused a 3-fold increase in potassium levels (3.78 ± 6.10) when compared with B (-0.14 ± 1.46) and C (1.63 ± 1.98) (P = .015). This pump also produced the worst changes, with an increase in free haemoglobin (0.05 ± 0.05; P = .038) and more haemolysis (0.08 ± 0.07; P = .033). There were significant differences and an increase in the degree of haemolysis (P = .004) at the infusion rate of 100 mL/h.

CONCLUSIONS

Syringe infusion pumps may cause significant red blood cell damage during infusion, with increases in free haemoglobin, potassium, and the degree of haemolysis. Some pump types, with a cassette mechanism, caused more damage.

RELEVANCE TO CLINICAL PRACTICE

In many intensive care units, bedside nurses are able to consider infusion pump choice, and understanding the impact of different pump types on red blood cells during a transfusion provides the nurses with more information to enhance decision-making and improve the quality of the transfusion.

Comparison of sublingual, facial and retro-bulbar blood sampling in mice in relation to animal welfare and blood quality

INTRODUCTION

Repeated blood sampling is a common procedure in laboratory mice, but at present it is unknown which technique has the least impact on the animals when large or repeated blood samples are required. Retro-bulbar sinus puncture is a reliable technique but has been shown to cause many changes in the animals, why sublingual and facial vein puncture have been suggested as suitable alternatives. This study investigated 1) which of the three blood sampling techniques had the least impact on nest building activity, level of faecal corticosterone metabolites, body weight, fur status, and macroscopic changes, 2) whether the blood sampling techniques gave rise to variation in blood quality between blood samples, and 3) whether sublingual and facial vein puncture should be performed with or without anaesthesia in female C57BL/6 mice.

METHOD

Three hundred and sixty C57BL/6 female mice divided into five batches were included in the study and randomized to a short (blood sampling on Day 8, 9 and 10) or a long protocol (blood sampling on Day 8, 15 and 22). Each protocol consisted of six identical groups: sublingual vein puncture (SVP), sublingual vein puncture in isoflurane (SVPiso), facial vein puncture (FVP), facial vein puncture in isoflurane (FVPiso), retro-bulbar sinus puncture (RBP), and a control group (CONTROL) with only scruffing being performed. At baseline (Day 2) nest building activity (NBA) was assessed and faecal pellets collected for evaluation of faecal corticosterone metabolites (FCM). The day after each blood sampling day NBA and FCM were reassessed.

RESULTS AND CONCLUSION

None of the blood sampling techniques proved to be superior to the others in any of the measured parameters. Finally, sublingual and facial vein puncture performed under anaesthesia gave rise to variation in the quality of the blood. A refinement of all three techniques are therefore warranted.

Piloting and implementation of quality assessment and quality control procedures in RBC-Omics: a large multi-center study of red blood cell hemolysis during storage

BACKGROUND

The major aims of the RBC-Omics study were to evaluate the genomic and metabolomic determinants of spontaneous and stress-induced hemolysis during RBC storage. This study was unique in scale and design to allow evaluation of RBC donations from a sufficient number of donors across the spectrum of race, ethnicity, sex, and donation intensity. Study procedures were carefully piloted, optimized, and controlled to enable high-quality data collection.

METHODS

The enrollment goal of 14,000 RBC donors across four centers, with characterization of RBC hemolysis across two testing laboratories, required rigorous piloting and optimization and establishment of a quality assurance (QA) and quality control (QC) program. Optimization of WBC elution from leukoreduction (LR) filters, development and validation of small-volume transfer bags, impact of manufacturing and sample-handling procedures on hemolysis parameters, and testing consistency across laboratories and technicians and over time were part of this quality assurance/quality control program.

RESULTS

LR filter elution procedures were optimized for obtaining DNA for analysis. Significant differences between standard and pediatric storage bags led to use of an alternative LR-RBC transfer bag. The impact of sample preparation and freezing methods on metabolomics analyses was evaluated. Proficiency testing monitored and documented testing consistency across laboratories and technicians.

CONCLUSION

Piloting and optimization, and establishment of a robust quality assurance/quality control program documented process consistency throughout the study and was essential in executing this large-scale multicenter study. This program supports the validity of the RBC-Omics study results and a sample repository that can be used in future studies.

Characterization of Storage-Induced Red Blood Cell Hemolysis Using Raman Spectroscopy

BACKGROUND

The therapeutic efficacy and safety of stored red blood cells (RBCs) relies on minimal in-bag hemolysis. The accuracy of current methods of measuring hemolysis can suffer as a result of specimen collection and processing artefacts.

OBJECTIVE

To test whether Raman spectroscopy could be used to assess hemolysis.

METHODS

RBCs were stored for as long as 42 days. Raman spectra of RBCs were measured before and after washing, and hemolysis was measured in supernatant by visible spectroscopy.

RESULTS

Raman spectra indicated increased concentrations of oxyhemoglobin (oxyHb) and methemoglobin (metHb), and decreased membrane fluidity with storage age. Changes in oxyHb and metHb were associated with the intraerythrocytic and extracellular fractions, respectively. Hemolysis increased in a storage age-dependent manner. Changes in Raman bands reflective of oxyHb, metHb, and RBC membranes correlated with hemolysis; the most statistically significant change was an increased intensity of metHb and decreased membrane fluidity.

CONCLUSIONS

These data suggest that Raman spectroscopy may offer a new label-free modality to assess RBC hemolysis during cold storage.

Screening of red blood cells for extracellular vesicle content as a product quality indicator

BACKGROUND

The controversy around the quality and clinical impact of stored and differentially manufactured red cell concentrates (RCCs) from different donor groups is ongoing. Current studies are limited by the lack of quality measures suitable for routine screening of RCCs. As extracellular vesicles (EVs) are markers of cellular activation or degradation, this study investigated the utility of EV screening to characterize the effects of RBCs production methods and storage.

STUDY DESIGN AND METHODS

RCCs were prepared by whole blood filtration or red blood cell (RBC) filtration methods, centrifuged to prepare a supernatant, and tested for EV content (dynamic light scattering or tunable resistive pulse-sensing techniques), hemolysis, ATP, and RBC deformability on Days 7, 21, and 42 of storage. To simulate nondestructive quality control (QC) testing, 1 RBC unit was tested in parallel with six 10-mL aliquots that were stored in small-volume containers.

RESULTS

EV content showed a linear increase with storage time (p < 0.001) and correlated with supernatant hemoglobin and inversely with ATP or RBC deformability. The method of component manufacturing influenced the characteristics of the EVs during storage. A strong correlation between both EV testing methods' measure of total EV was observed. EV content in the six aliquots were consistent at each time point but statistically higher than in the original RCCs on and after 21 days of storage.

CONCLUSIONS

EV content correlates with measures of hemolysis and other RBC quality indicators and could be implemented as a routine screening tool for nondestructive QC testing of RCCs.

Preparation and Evaluation of Progesterone Nanocrystals to Decrease Muscle Irritation and Improve Bioavailability

Progesterone (PG) is a crucial immunomodulatory agent during early pregnancy, and nowadays PG oil-based injection (PG/OI) has a huge market all over the world. However, PG/OI may accumulate the local muscle and further cause irritations after long-term administration. In this study, PG nanocrystals (PG/NCs) injection was developed to decrease muscle toxicity. PG/NCs injection containing 10% (w/v) PG was first prepared using a wet grinding method. Then, particle size, zeta potential, morphology powder, X-ray diffraction (PXRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) studies were carried out to evaluate the characteristics of dosage form. The rabbit muscle irritation, hemolysis, and rat pharmacokinetics tests were used to estimate the in vivo characteristics of PG/NCs. The results showed that the mean particle size and the zeta potentials of NCs were 299.5 ± 9.0 nm and - 36.8 ± 1.5 mV, respectively. The crystalline state of PG/NCs was not altered during particle size reduction according to PXRD, DSC, and FTIR results. Muscle irritation presented that PG/NCs had lower irritation than that of PG/OI. Hemolysis test suggested that PG/NCs injection was functioned without hemolysis and red cell agglutination. The pharmacokinetics study showed that the AUC_0-t and C_max of PG/NCs was 3.2-fold (p < 0.05) and 3.1-fold higher than PG/OI, which demonstrated that PG/NCs injection had greater bioavailability than PG/OI. Therefore, it was obvious that PG/NCs injection exhibited a lower muscle irritation, hemolysis rate, and higher bioavailability, which was a better dosage form than OI.

In vitro evaluation of di(2-ethylhexyl)terephthalate-plasticized polyvinyl chloride blood bags for red blood cell storage in AS-1 and PAGGSM additive solutions

BACKGROUND

Di(2-ethylhexyl)phthalate (DEHP) makes polyvinyl chloride flexible for use in blood bags and stabilizes the red blood cell (RBC) membrane preventing excessive hemolysis. DEHP migrates into the blood product and rodent studies have suggested that DEHP exposure may be associated with adverse health effects albeit at high dosages. Although structurally and functionally similar to DEHP, di(2-ethylhexyl)terephthalate (DEHT; or Eastman 168 SG [Eastman Chemical Company]) is metabolically distinct with a comprehensive and benign toxicology profile. This study evaluated RBC stability in DEHT-plasticized bags with AS-1 and PAGGSM compared to conventional DEHP-plasticized bags with AS-1.

STUDY DESIGN AND METHODS

Thirty-six whole blood units were collected into CPD solution, leukoreduced, centrifuged, and divided into RBCs and plasma. To limit donor-related variability, three ABO-identical RBCs were mixed together and then divided equally and stored among the three different plasticizer and additive solution combinations. RBCs from 12 trios were analyzed for a standard panel of in vitro variables on Day 0 and after storage.

RESULTS

No individual bag on Day 42 exceeded the US 1.0% hemolysis criteria. While hemolysis during storage was higher in the DEHT bags, the PAGGSM RBCs were close to the control RBCs (0.38% vs. 0.32%, respectively). ATP retention was higher than 70% and potassium levels were similar regardless of plasticizer. Additional RBC variables exhibited some significant differences but were not viewed as clinically important.

CONCLUSION

DEHT/PAGGSM provides similar hemolysis protection to that of DEHP/AS-1. Although hemolysis values with DEHT and AS-1 are higher than that of DEHP, DEHT is a potential DEHP alternative.

Mechanisms of red blood cell transfusion-related immunomodulation

Red blood cell (RBC) transfusion is common in critically ill, postsurgical, and posttrauma patients in whom both systemic inflammation and immune suppression are associated with adverse outcomes. RBC products contain a multitude of immunomodulatory mediators that interact with and alter immune cell function. These interactions can lead to both proinflammatory and immunosuppressive effects. Defining clinical outcomes related to immunomodulatory effects of RBCs in transfused patients remains a challenge, likely due to complex interactions between individual blood product characteristics and patient-specific risk factors. Unpacking these complexities requires an in-depth understanding of the mechanisms of immunomodulatory effects of RBC products. In this review, we outline and classify potential mediators of RBC transfusion-related immunomodulation and provide suggestions for future research directions.

Proceedings of the Food and Drug Administration's public workshop on new red blood cell product regulatory science 2016

The US Food and Drug Administration (FDA) held a workshop on red blood cell (RBC) product regulatory science on October 6 and 7, 2016, at the Natcher Conference Center on the National Institutes of Health (NIH) Campus in Bethesda, Maryland. The workshop was supported by the National Heart, Lung, and Blood Institute, NIH; the Department of Defense; the Office of the Assistant Secretary for Health, Department of Health and Human Services; and the Center for Biologics Evaluation and Research, FDA. The workshop reviewed the status and scientific basis of the current regulatory framework and the available scientific tools to expand it to evaluate innovative and future RBC transfusion products. A full record of the proceedings is available on the FDA website (http://www.fda.gov/BiologicsBloodVaccines/NewsEvents/WorkshopsMeetingsConferences/ucm507890.htm). The contents of the summary are the authors' opinions and do not represent agency policy.