Red blood cell transfusion: a clinical practice guideline from the AABB*

Association of perioperative red blood cell transfusions with all-cause and cancer-specific death in patients undergoing surgery for gastrointestinal cancer: Long-term outcomes from a population-based cohort

BACKGROUND

Red blood cell transfusions are common in patients undergoing gastrointestinal cancer surgery. Yet, to adequately balance their risks and benefits, clinicians must understand how transfusions may affect long-term outcomes. We aimed to determine if perioperative red blood cell transfusions are associated with a higher risk of all-cause and cancer-specific death among patients who underwent gastrointestinal cancer resection.

METHOD

We identified a population-based cohort of patients who underwent gastrointestinal cancer resection in Ontario, Canada (2007-2019). All-cause death was compared between transfused and nontransfused patients using Cox proportional hazards regression, while cancer-specific death was compared with competing risk regression.

RESULT

A total of 74,962 patients (mean age, 67.7 years; 55.4% male; 79.7% colorectal cancer) had gastrointestinal cancer surgery during the study period; 20.8% received perioperative red blood cell transfusions. Patients who received red blood cell transfusions had increased hazards of all-cause and cancer-specific death relative to patients who did not (hazard ratio: 1.39, 95% confidence interval 1.34-1.44; cause-specific hazard ratio: 1.36, 1.30-1.43). The adjusted risk of all-cause death was higher in early follow-up intervals (3-6 months postoperatively) but remained elevated in each interval over 5 years. The association persisted after restricting to patients without postoperative complications or bleeding and was robust to unmeasured confounding.

CONCLUSION

Red blood cell transfusion among patients with gastrointestinal cancer is associated with increased all-cause death. This was observed long beyond the immediate postoperative period and independent of short-term postoperative morbidity and mortality. These findings should help clinicians balance the risks and benefits of transfusion before well-designed trials are conducted in this patient population.

Roxadustat for Treating Anemia in Patients with CKD Not on Dialysis: Results from a Randomized Phase 3 Study

BACKGROUND

Current anemia therapies for patients with non-dialysis-dependent CKD may require injection and medical visits. Roxadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, stimulates erythropoiesis and improves iron homeostasis.

METHODS

In this double-blind phase 3 study, we randomized patients with non-dialysis-dependent CKD stages 3-5 and hemoglobin <10.0 g/dl (1:1) to thrice-weekly 70-mg oral roxadustat or placebo. Doses were titrated throughout the study based on hemoglobin levels. The primary efficacy end point was mean change from baseline in hemoglobin averaged over weeks 28-52 versus placebo, irrespective of rescue therapy use. We assessed patients for adverse events.

RESULTS

The study included 2781 patients, 1393 who received roxadustat and 1388 who received placebo. Mean baseline hemoglobin was 9.1 g/dl for both groups. The mean change in hemoglobin from baseline was 1.75 g/dl (95% confidence interval [95% CI], 1.68 to 1.81) with roxadustat versus 0.40 g/dl (95% CI, 0.33 to 0.47) with placebo, (P<0.001). Among 411 patients with baseline elevated high-sensitivity C-reactive protein, mean change in hemoglobin from baseline was 1.75 g/dl (95% CI, 1.58 to 1.92) with roxadustat versus 0.62 g/dl (95% CI, 0.44 to 0.80) with placebo, (P<0.001). Roxadustat reduced the risk of red blood cell transfusion by 63% (hazard ratio, 0.37; 95% CI, 0.30 to 0.44). The most common adverse events with roxadustat and placebo, respectively, were ESKD (21.0% versus 20.5%), urinary tract infection (12.8% versus 8.0%), pneumonia (11.9% versus 9.4%), and hypertension (11.5% versus 9.1%).

CONCLUSIONS

Roxadustat effectively increased hemoglobin in patients with non-dialysis-dependent CKD and reduced the need for red blood cell transfusion, with an adverse event profile comparable to that of placebo.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Safety and Efficacy Study of Roxadustat to Treat Anemia in Patients With CKD, Not on Dialysis, NCT02174627.

Step-clipping method can improve the detectability of the target lesion in colonic diverticular bleeding

Background and study aims  Despite the information regarding extravasation from contrast-enhanced computed tomography (CECT), the detectability of the target diverticulum by colonoscopy remains unsatisfactory in colonic diverticular bleeding (CDB). The lack of common signs recognizable on CT and endoscopic images makes it difficult to set a region of interest; however, this can be overcome with the "step-clipping" method, a strategic marking technique for revealing the target. We aimed to investigate the clinical performance of the step-clipping method in patients with CDB. Patients and methods  Eighty-seven patients diagnosed with CDB with extravasation using CECT who underwent colonoscopy between August 2007 and February 2020 were included. Patients were divided into two categories: the traditional group (those who underwent colonoscopy from August 2007 to May 2017, n = 54) and the step-clipping group (those who underwent colonoscopy from June 2017 to February 2020, n = 33). Results  The detection rate for the responsible diverticulum was significantly higher in the step-clipping group than in the traditional group (94 % vs 63 %; P  = .0013). The step-clipping group had a shorter average search time during colonoscopy (9.6 vs 40.5 minutes; P  < .0001) and lower re-bleeding rate after the initial colonoscopy (6 % vs 26 %; P  = .02) than the traditional group, which facilitated earlier hospital discharge (5.4 vs 6.8 days; P  = .027). Conclusions  Colonoscopy using the step-clipping method can improve the detectability of the target lesion within a shorter time, thus leading to lower re-bleeding rates and earlier hospital discharge.

Intraoperative blood loss may be associated with myocardial injury after non-cardiac surgery

BACKGROUND

This study aimed to evaluate the association between intraoperative blood loss and myocardial injury after non-cardiac surgery (MINS), which is a severe and common postoperative complication.

METHODS

We compared the incidence of MINS based on significant intraoperative bleeding, defined as an absolute hemoglobin level < 7 g/dL, a relative hemoglobin level less than 50% of the preoperative measurement, or need for packed red cell transfusion. We also estimated a threshold for intraoperative hemoglobin level associated with MINS.

RESULTS

We stratified a total of 15,926 non-cardiac surgical patients with intraoperative hemoglobin and postoperative cardiac troponin (cTn) measurements according to the occurrence of significant intraoperative bleeding; 13,416 (84.2%) had no significant bleeding while 2,510 (15.8%) did have significant bleeding. After an adjustment with inverse probability weighting, the incidence of MINS was higher in the significant bleeding group (35.2% vs. 16.4%; odds ratio, 1.58; 95% confidence interval, 1.43-1.75; p < 0.001). The threshold of intraoperative hemoglobin associated with MINS was estimated to be 9.9 g/dL with an area under the curve of 0.643.

CONCLUSION

Intraoperative blood loss appeared to be associated with MINS. Further studies are needed to confirm these findings.

CLINICAL REGISTRATION

The cohort was registered before patient enrollment at https://cris.nih.go.kr (KCT0004244).

Trends in Erythropoiesis-stimulating agent use and blood transfusions for chemotherapy-induced anemia throughout FDA's risk evaluation and mitigation strategy lifecycle

PURPOSE

Erythropoiesis-stimulating agents (ESAs), indicated for treating some patients with chemotherapy-induced anemia (CIA), may increase the risk of tumor progression and mortality. FDA required a Risk Evaluation and Mitigation Strategy (REMS) to mitigate these risks. We assessed REMS impact on ESA administration and red blood cell (RBC) transfusion as surrogate metrics for REMS effectiveness.

METHODS

Retrospective cohort study including data from January 1, 2006 to December 31, 2018 for beneficiaries ≥65 years enrolled in Centers for Medicare & Medicaid Services (CMS) Medicare Parts A/B with a cancer diagnosis; patients with other indications for ESA use were excluded. Study time was divided into five periods demarcated by issuance of CMS National Coverage Determination (NCD) (Pre-NCD, Pre-REMS) and REMS milestones (Grace Period, REMS, post-REMS). Study outcomes were monthly proportion of chemotherapy episodes (CTEs) with concomitant ESA administration, with post-CTE ESA administration, and with RBC transfusions.

RESULTS

Of 1 778 855 beneficiaries treated with CT, 308742 received concomitant ESA for CIA. The proportion of CTEs with concomitant and post-CTE ESA administration decreased Pre-REMS (9.0 percentage points [pp] and 3.5 pp, respectively). There were no significant post-REMS changes in the proportion of CTEs with concomitant (0.0 pp) and post-CTE ESA administration (0.1 pp). Fluctuation in RBC transfusions was <4 pp throughout the study period.

CONCLUSIONS

Medicare beneficiaries showed a substantive decrease in ESA administration after NCD, with minimal impact by the REMS and its removal. Small changes in RBC transfusion over the study period were likely due to a national secular trend.

Function of Hemoglobin-Based Oxygen Carriers: Determination of Methemoglobin Content by Spectral Extinction Measurements

Suspensions of hemoglobin microparticles (HbMPs) are promising tools as oxygen therapeutics. For the approval of clinical studies extensive characterization of these HbMPs with a size of about 750 nm is required regarding physical properties, function, pharmaco-kinetics and toxicology. The standard absorbance measurements in blood gas analyzers require dissolution of red blood cells which does not work for HbMP. Therefore, we have developed a robust and rapid optical method for the quality and functionality control of HbMPs. It allows simultaneous determination of the portion of the two states of hemoglobin oxygenated hemoglobin (oxyHb) and deoxygenated hemoglobin (deoxyHb) as well as the content of methemoglobin (metHb). Based on the measurement of collimated transmission spectra between 300 nm and 800 nm, the average extinction cross section of HbMPs is derived. A numerical method is applied to determine the composition of the HbMPs based on their wavelength-dependent refractive index (RI), which is a superposition of the three different states of Hb. Thus, light-scattering properties, including extinction cross sections can be simulated for different compositions and sizes. By comparison to measured spectra, the relative concentrations of oxyHb, deoxyHb, metHb are accessible. For validation of the optically determined composition of the HbMPs, we used X-ray fluorescence spectrometry for the ratio of Fe(II) (oxyHb/deoxyHb) and Fe(III) (metHb). High accuracy density measurements served to access heme-free proteins, size was determined by dynamic light scattering and analytical centrifugation and the shape of the HbMPs was visualized by electron and atomic force microscopy.

Optimizing Inpatient Blood Utilization Using Real-Time Clinical Decision Support

BACKGROUND

Red blood cell (RBC) transfusion is a common medical procedure. While it offers clinical benefits for many, hemodynamically stable patients are often subjected to unwarranted transfusions, with the potential to lead to adverse consequences. We created a real-time clinical decision support (CDS) tool in the electronic health record system to address this problem and optimize transfusion practice as part of an institutional multidisciplinary, team-based patient blood management program.

METHODS

The real-time CDS tool incorporated the transfusion guidelines published by the AABB. The tool was deployed as a dynamic order set within the computerized provider order entry interface. Prior to implementation, extensive education and outreach to increase provider engagement were provided. The CDS tool was launched in September 2015.

RESULTS

The percentage of guideline-indicated RBC transfusions increased from a baseline of 43.6 to 54.2% while the percentage of multiunit (≥ 2 units) RBC transfusions decreased from 31.3 to 22.7% between September 2014 and July 2019. The estimated minimum cost saving over the entire study period was $36,519.36.

CONCLUSION

Our intervention increased guideline-indicated transfusions by 10.6% and reduced multiunit transfusions by 8.6%. The adoption of a dynamic order set for the CDS tool, as opposed to an interruptive alert that displays static alert messages, allowed for more customized and tighter control of RBC orders, leading to a sustained improvement in our transfusion practice.

A protocol of situation-dependent transfusion, erythropoietin and tranexamic acid reduces transfusion in fronto-orbital advancement for metopic and coronal craniosynostosis

PURPOSE

Assess the effect of a protocol of preoperative erythropoietin (EPO) and ferrous sulfate in addition to perioperative tranexamic acid (TXA) on blood transfusions in patients with coronal or metopic craniosynostosis undergoing cranial vault remodeling (CVR) with fronto-orbital advancement (FOA).

METHODS

Retrospective review of all coronal and metopic craniosynostosis patients undergoing CVR and FOA from March 2010 to June 2019 was performed. Before 2014 ("Control group"), all patients received blood transfusion at the start of surgery. In 2014, a protocol of preoperative EPO and ferrous sulfate with perioperative TXA and non-automatic transfusion was instituted ("Study group"). Patient demographics and anthropometrics, perioperative hemoglobin (Hb) levels, and transfusion details were collected and compared.

RESULTS

Thirty-six patients met inclusion criteria. Twenty-one patients were in the control group, and 15 in the Study group. Nineteen patients had metopic synostosis, 11 had unicoronal synostosis, and 6 had bicoronal synostosis. There were no significant differences between groups in demographics, operative time, intraoperative crystalloid volume, craniofacial syndromes, or sutures affected. The Study group had higher preoperative Hb (13.9 ± 1.0 vs. 12.6 ± 0.8 g/dL, p < 0.001), lower intraoperative Hb nadir (7.4 ± 1.8 vs. 9.2 ± 1.2 g/dL) lower intraoperative transfusion rate (66.7% vs. 100%, p = 0.008), lower postoperative transfusion rate (0% vs 28.6%, p = 0.03), and exposure to fewer unique units of packed red blood cells (0.7 ± 0.6 vs. 1.5 ± 0.9 units).

CONCLUSION

Our protocol resulted in decreased transfusion needs. These results add valuable information to the growing body of work on transfusion reduction in craniosynostosis surgery.

Differences in emergency endoscopy outcomes according to gastrointestinal bleeding location

BACKGROUND AND AIM

With recent technological advances in the field of endoscopic hemostasis, the prognosis of patients with gastrointestinal (GI) bleeding has improved. However, few studies have reported on the clinical course of patients with GI bleeding. This study aimed to evaluate the differences in clinical outcomes of patients with lower GI bleeding (LGIB) compared with upper GI bleeding (UGIB) and the factors related to their prognosis.

METHODS

Patients who had undergone emergency endoscopy for GI bleeding were retrospectively reviewed. The severity of GI bleeding was evaluated using the Glasgow-Blatchford (GB), AIMS65, and NOBLADS scores. Patients in whom obvious GI bleeding relapsed and/or iron deficiency anemia persisted after emergency endoscopy were considered to exhibit rebleeding.

RESULTS

We reviewed 1697 consecutive patients and divided them into UGIB (1054 patients) and LGIB (643 patients) groups. The proportion of patients with rebleeding was significantly greater in the UGIB group than in the LGIB group; the mortality rate was significantly higher in the UGIB group than in the LGIB group. Multivariate analysis showed that a GB score ≥12 and an AIMS65 score ≥2 were significantly associated with rebleeding in the UGIB group, whereas a NOBLADS score ≥4 was significantly associated with rebleeding in the LGIB group. Notably, the influence of emergency endoscopy differed according to GI bleeding location.

CONCLUSIONS

The clinical course was significantly worse in patients with UGIB than in patients with LGIB. The influence of emergency endoscopy differed according to GI bleeding location.

Defining postoperative transfusion thresholds in liver transplant recipients: A novel retrospective approach

BACKGROUND

The optimal transfusion threshold for most patient populations has been defined as hematocrit (HCT) <21%. However, some specific patient populations are known to benefit from higher transfusion thresholds. To date, the optimal postoperative transfusion threshold for patients undergoing liver transplant has not been determined. To define the ideal transfusion threshold for liver transplant patients, we designed a retrospective study of 496 liver transplant recipients.

METHODS

Using HCT prior to discharge as a surrogate marker for transfusion thresholds we grouped patients into three groups of transfusion thresholds (HCT <21%, <24%, and >30%). Transfusion rates (intra- and postoperative), graft and patient survival, and complications requiring readmission were compared between groups.

RESULTS

Ninety-two percent of patients were transfused during their hospital stay. Graft survival, patient survival, and rates of readmission within 30 days of discharge were no different between the three discharge HCT groups. Patients discharged with HCT >30% were less likely to be readmitted with infectious complications; however, this group also had the lowest model of end-stage liver (MELD) score at time of transplantation and were less likely to have received a transfusion during their hospital stay.

CONCLUSION

Transfusion thresholds of HCT <24%, and potentially as low as 21% are acceptable in postoperative liver transplant recipients. The conduct of a randomized clinical trial, as supported by these data, will be necessary to support the use of lower thresholds.

Daily blood loss transition after total knee arthroplasty with topical administration of tranexamic acid: Paradoxical blood loss after action of tranexamic acid

PURPOSE

The purpose of this study was to compare the daily blood loss transition between groups with and without topical administration of tranexamic acid (TXA) after cruciate retaining (CR) and posterior stabilized (PS) total knee arthroplasty (TKA).

METHODS

A total of 220 patients undergoing unilateral TKA were enrolled in CR and PS TKAs, which were divided into groups that received topical administration of TXA (TXA group) or without TXA (non-TXA group). Each group in both types of TKA included 55 patients. The daily transition of blood loss was compared between the TXA and the non-TXA groups in CR and PS TKAs. The blood loss was calculated through Nadler formula using the patient's blood volume and hemoglobin reduction rate.

RESULTS

Total blood loss was significantly lower in the TXA group in both CR and PS TKAs (p < 0.001, respectively). The blood loss was lower for 0-24 h and 24-48 h after TKA. However, from 48 h to 72 h, it was greater in the TXA group (253.1 vs. 34.6 mL; p < 0.001) in CR TKAs. These tendencies were similar in PS TKAs after 48 h (186.2 vs. 134.9 mL, p = 0.223).

CONCLUSIONS

Topical administration of TXA for reduction of blood loss seemed to be effective up to 48 h after both CR and PS TKAs. The blood loss after 48 h tended to be even greater in the TXA group. Future studies will be required to identify the pharmacokinetic evidence for this clinical finding.

LEVEL OF EVIDENCE

Level II.

Prognostic impact of perioperative blood transfusions on oncological outcomes of patients with bladder cancer undergoing radical cystectomy: A systematic review

Objective: To conduct a systematic review of whether blood transfusions may be associated with worse outcomes for patients with bladder cancer treated with radical cystectomy (RC), as there has been a recent increase in studies addressing this clinically relevant topic. Methods: PubMed, Ovid Medical Literature Analysis and Retrieval System Online (MEDLINE), Google Scholar, and the ClinicalTrials.gov databases were searched with pre-specified search terms for studies published between January 2010 and May 2020. The systemic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: A total of 17 studies with 19 627 patients were included after 183 records were screened for eligibility. In all, 10 studies proposed perioperative blood transfusion to be associated with impaired prognosis regarding overall survival, nine studies regarding cancer-specific and four studies regarding recurrence-free survival. The timing of blood transfusion might affect patient outcomes. Notably, several studies did not find a significant correlation between blood transfusions and prognosis. As all studies to date are of retrospective design, the grade of evidence is still limited. Conclusions: Despite the lack of prospective trials, perioperative blood transfusion may lead to worse oncological outcomes. These results, as well as known non-oncological side-effects and associated costs, are important arguments to carefully consider the indication for blood transfusion. Abbreviations BCa: bladder cancer; CSS: cancer-specific survival; HR: hazard ratio; (N)MIBC: (non-) muscle-invasive BCa; OS: overall survival; PBT, perioperative blood transfusion; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RC: radical cystectomy; RFS: recurrence-free survival.

Prolonged Weaning: S2k Guideline Published by the German Respiratory Society

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by respiratory muscle insufficiency and/or lung parenchymal disease; that is, when other treatments such as medication, oxygen administration, secretion management, continuous positive airway pressure (CPAP), or nasal high-flow therapy have failed. MV is required for maintaining gas exchange and allows more time to curatively treat the underlying cause of respiratory failure. In the majority of ventilated patients, liberation or "weaning" from MV is routine, without the occurrence of any major problems. However, approximately 20% of patients require ongoing MV, despite amelioration of the conditions that precipitated the need for it in the first place. Approximately 40-50% of the time spent on MV is required to liberate the patient from the ventilator, a process called "weaning". In addition to acute respiratory failure, numerous factors can influence the duration and success rate of the weaning process; these include age, comorbidities, and conditions and complications acquired during the ICU stay. According to international consensus, "prolonged weaning" is defined as the weaning process in patients who have failed at least 3 weaning attempts, or require more than 7 days of weaning after the first spontaneous breathing trial (SBT). Given that prolonged weaning is a complex process, an interdisciplinary approach is essential for it to be successful. In specialised weaning centres, approximately 50% of patients with initial weaning failure can be liberated from MV after prolonged weaning. However, the heterogeneity of patients undergoing prolonged weaning precludes the direct comparison of individual centres. Patients with persistent weaning failure either die during the weaning process, or are discharged back to their home or to a long-term care facility with ongoing MV. Urged by the growing importance of prolonged weaning, this Sk2 Guideline was first published in 2014 as an initiative of the German Respiratory Society (DGP), in conjunction with other scientific societies involved in prolonged weaning. The emergence of new research, clinical study findings and registry data, as well as the accumulation of experience in daily practice, have made the revision of this guideline necessary. The following topics are dealt with in the present guideline: Definitions, epidemiology, weaning categories, underlying pathophysiology, prevention of prolonged weaning, treatment strategies in prolonged weaning, the weaning unit, discharge from hospital on MV, and recommendations for end-of-life decisions. Special emphasis was placed on the following themes: (1) A new classification of patient sub-groups in prolonged weaning. (2) Important aspects of pulmonary rehabilitation and neurorehabilitation in prolonged weaning. (3) Infrastructure and process organisation in the care of patients in prolonged weaning based on a continuous treatment concept. (4) Changes in therapeutic goals and communication with relatives. Aspects of paediatric weaning are addressed separately within individual chapters. The main aim of the revised guideline was to summarize both current evidence and expert-based knowledge on the topic of "prolonged weaning", and to use this information as a foundation for formulating recommendations related to "prolonged weaning", not only in acute medicine but also in the field of chronic intensive care medicine. The following professionals served as important addressees for this guideline: intensivists, pulmonary medicine specialists, anaesthesiologists, internists, cardiologists, surgeons, neurologists, paediatricians, geriatricians, palliative care clinicians, rehabilitation physicians, intensive/chronic care nurses, physiotherapists, respiratory therapists, speech therapists, medical service of health insurance, and associated ventilator manufacturers.

Same-Day Bilateral Total Knee Arthroplasty: Incidence and Perioperative Outcome Trends from 2009 to 2016

BACKGROUND

Same-day bilateral total knee arthroplasty (BiTKA) is a controversial topic in orthopedics, prompting a consensus statement to be released by national experts. To date, no studies have evaluated the trends of this method since these recommendations. This study utilized a national database to evaluate: 1) incidence; 2) patient characteristics; 3) hospital characteristics; and 4) inpatient course for same-day BiTKAs in the United States from 2009 to 2016.

METHOD

The National Inpatient Sample database was queried for individuals undergoing same-day BiTKAs, yielding 245,138 patients. Patient demographics included age, sex, race, obesity status and Charlson Comorbidity Index (CCI) score. Hospital characteristics consisted of location/teaching status, geographic region, charges, and costs. Inpatient course included length of stay, discharge disposition, and complications.

RESULTS

Same-day BiTKA incidence decreased from 5.6% to 4.0% over the study (p < 0.001). Decreases in patient age and female proportion (p < 0.001 for both) were seen, while African American and Hispanic patients increased (p < 0.001), as did obese patient proportions (p < 0.001). Patients with CCI scores of 2 increased, while those with ≥3 decreased (p < 0.001). Hospital charges increased, while costs decreased (p < 0.001 for both). Length of stay following same-day BiTKA decreased (p < 0.001) and routine home discharges increased (p < 0.001). Most inpatient complications decreased, although the percentage of mechanical complications and respiratory failures increased (p < 0.01 for all).

CONCLUSIONS

During the study period, younger patients with fewer comorbidities underwent BiTKAs, which likely resulted from improved patient assessment and management. Future investigations should include an evaluation of long-term complications and outcomes in certain patient populations for this procedure.

Mixed-type autoimmune hemolytic anaemia presenting as multiple thromboses: A case report

Autoimmune hemolytic anaemia (AIHA) is a heterogenous disorder characterised by the presence of IgG or IgM pathological autoantibodies that target antigens of erythrocytes resulting in active hemolysis. Case presentation: A 40-year-old gentleman presented to a medical centre with chest pain and right sided hemiparesis for a week. He was pale and jaundiced. The power of the right upper and lower limbs was 3/5. His spleen was palpable. His complete blood count revealed macrocytic anaemia of 7.6 g/dL. The brain Magnetic Resonance Imaging (MRI) showed left fronto-parietal infarction. The right cardiac and left carotid angiogram revealed thromboses involving the right coronary and left internal carotid artery respectively. At the cardiology department, he was transfused with two units of red blood cells without his anemia being investigated and a stent was deployed to the left internal carotid artery. He was referred to the hematology department in which his peripheral blood smear revealed hemolysis and his direct antiglobulin test was positive. He responded to a course of steroids and direct oral anticoagulation and is in complete remission for the past 18 months. Conclusion: It is always imperative to investigate the cause of anaemia and consider hemolysis in a patient presenting with multiple unexplained thromboses.

Emerging use of machine learning and advanced technologies to assess red cell quality

Improving blood product quality and patient outcomes is an accepted goal in transfusion medicine research. Thus, there is an urgent need to understand the potential adverse effects on red blood cells (RBCs) during pre-transfusion storage. Current assessment techniques of these degradation events, termed "storage lesions", are subjective, labor-intensive, and complex. Here we describe emerging technologies that assess the biochemical, biophysical, and morphological characteristics of RBC storage lesions. Of these emerging techniques, machine learning (ML) has shown potential to overcome the limitations of conventional RBC assessment methods. Our previous work has shown that neural networks can extract chronological progressions of morphological changes in RBCs during storage without human input. We hypothesize that, with broader training and testing of multivariate data (e.g., varying donor factors and manufacturing methods), ML can further our understanding of clinical transfusion outcomes in multiple patient groups.

Blood transfusion trends by disease category in the United States, 2000 to 2014

BACKGROUND

Better understanding of blood usage rates could identify trends in transfusion practices over time and inform more efficient management.

METHODS

Inpatient admissions from the Healthcare Cost and Utilization Project National Inpatient Sample and State Inpatient Databases were analyzed for packed red blood cell (PRBC), plasma, platelet, and whole blood (WB) transfusions. The transfusion rates per admission and per prevalent case were calculated. Prevalence estimates were from the Global Burden of Disease 2017 study (GBD).

RESULTS

From 2000 to 2014, blood usage rates for most causes peaked around 2010. Across all causes, PRBC were the most commonly transfused component, followed by plasma, platelets, and WB. However, the relative use of each type varied by cause. Nutritional deficiencies (1.75 blood product units across all components per admission; 95 % uncertainty interval (UI) 1.62-1.87), neoplasms (0.95; 0.87-1.04), and injuries (0.92; 0.86 - 0.98) had the greatest blood use per admission. Cardiovascular diseases (96.9 units per 1000 prevalent cases; 89.3-105.0) and neoplasms (92.7 units per 1000 prevalent cases; 84.3-101.5) had the greatest blood use per prevalent case. Across all admissions, over three million blood units were saved in 2014 compared to 2011 due to transfusing at a reduced rate.

CONCLUSIONS

Blood transfusion rates decreased from 2011 to 2014 in the United States. This decline occurred in most disease categories, which points towards broad strategies like patient blood management systems and disease specific improvements like changes in surgical techniques being effective.

Blood Donation and COVID-19: Reconsidering the 3-Month Deferral Policy for Gay, Bisexual, Transgender, and Other Men Who Have Sex With Men

In April 2020, in light of COVID-19-related blood shortages, the US Food and Drug Administration (FDA) reduced the deferral period for men who have sex with men (MSM) from its previous duration of 1 year to 3 months.Although originally born out of necessity, the decades-old restrictions on MSM donors have been mitigated by significant advancements in HIV screening, treatment, and public education. The severity of the ongoing COVID-19 pandemic-and the urgent need for safe blood products to respond to such crises-demands an immediate reconsideration of the 3-month deferral policy for MSM.We review historical HIV testing and transmission evidence, discuss the ethical ramifications of the current deferral period, and examine the issue of noncompliance with donor deferral rules. We also propose an eligibility screening format that involves an individual risk-based screening protocol and, unlike current FDA guidelines, does not effectively exclude donors on the basis of gender identity or sexual orientation. Our policy proposal would allow historically marginalized community members to participate with dignity in the blood donation process without compromising blood donation and transfusion safety outcomes.

Declining Use of Red Blood Cell Transfusions for Gastrointestinal Cancer Surgery: A Population-Based Analysis

BACKGROUND

Gastrointestinal cancer surgery patients often develop perioperative anemia commonly treated with red blood cell (RBC) transfusions. Given the potential associated risks, evidence published over the past 10 years supports restrictive transfusion practices and blood conservation programs. Whether transfusion practices have changed remains unclear. We describe temporal RBC transfusion trends in a large North American population who underwent gastrointestinal cancer surgery.

METHODS

We conducted a population-based retrospective cohort study of patients who underwent gastrointestinal cancer resection between 2007 and 2018 using health administrative datasets. The outcome was RBC transfusion during hospitalization. Temporal transfusion trends were analyzed with Cochran-Armitage tests. Multivariable regression assessed the association between year of diagnosis and likelihood of RBC transfusion while controlling for confounding.

RESULTS

Of 79,764 patients undergoing gastrointestinal cancer resection, the median age was 69 years old (interquartile range (IQR) 60-78 years) and 55.5% were male. The most frequent procedures were colectomy (52.8%) and proctectomy (23.0%). A total of 18,175 patients (23%) received RBC transfusion. The proportion of patients transfused decreased from 26.5% in 2007 to 18.9% in 2018 (p < 0.001). After adjusting for patient, procedure, and hospital factors, the most recent time period (2015-2018) was associated with a reduced likelihood of receiving RBC transfusion [relative risk 0.86 (95% confidence interval: 0.83-0.89)] relative to the intermediate time period (2011-2014).

CONCLUSION

Over 11 years, we observed decreased RBC transfusion use and reduced likelihood of transfusion in patients undergoing gastrointestinal cancer resection. This information provides a foundation to further examine transfusion appropriateness or explore if additional transfusion minimization in surgical patients can be achieved.

The Optimal Dosing Regimen for Tranexamic Acid in Revision Total Hip Arthroplasty: A Multicenter Randomized Clinical Trial

BACKGROUND

The purpose of this multicenter, randomized trial was to determine the optimal dosing regimen of tranexamic acid (TXA) to minimize perioperative blood loss in revision total hip arthroplasty.

METHODS

Six centers prospectively randomized 175 patients to 1 of 4 regimens: (1) 1-g intravenous (IV) TXA prior to incision (the single-dose IV group), (2) 1-g IV TXA prior to incision followed by 1-g IV TXA after arthrotomy wound closure (the double-dose IV group), (3) a combination of 1-g IV TXA prior to incision and 1-g intraoperative topical TXA (the combined IV and topical group), or (4) 3 doses totaling 1,950-mg oral TXA (the multidose oral group). Randomization was based on revision subgroups to ensure equivalent group distribution. An a priori power analysis (α = 0.05; β = 0.80) determined that 40 patients per group were required to identify a >1-g/dL difference in postoperative hemoglobin reduction between groups. Per-protocol analysis involved an analysis of variance, Fisher exact tests, and two 1-sided t tests for equivalence. Demographic and surgical variables were equivalent between groups.

RESULTS

No significant differences were found between TXA regimens when evaluating reduction in hemoglobin (3.4 g/dL for the single-dose IV group, 3.6 g/dL for the double-dose IV group, 3.5 g/dL for the combined IV and topical group, and 3.4 g/dL for the multidose oral group; p = 0.95), calculated blood loss (p = 0.90), or transfusion rates (14% for the single-dose IV group, 18% for the double-dose IV group, 17% for the combined group, and 17% for the multidose oral group; p = 0.96). Equivalence testing revealed that all possible pairings were statistically equivalent, assuming a >1-g/dL difference in hemoglobin reduction as clinically relevant. There was 1 venous thromboembolism, with no differences found between groups (p = 1.00).

CONCLUSIONS

All 4 TXA groups tested had equivalent blood-sparing properties in the setting of revision total hip arthroplasty, with a single venous thromboembolism reported in this high-risk population. Based on the equivalence between groups, surgeons should utilize whichever of the 4 investigated regimens is best suited for their practice and hospital setting. Given the transfusion rate in revision total hip arthroplasty despite TXA utilization, further work is required in this area.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Tethering of the IgG1 Antibody to Amorphous Silica for Immunosensor Development: A Molecular Dynamics Study

A key factor for improving the sensitivity and performance of immunosensors based on mechanical-plasmonic methods is the orientation of the antibody proteins immobilized on the inorganic surface. Although experimental techniques fail to determine surface phenomena at the molecular level, modern simulations open the possibility for improving our understanding of protein-surface interactions. In this work, replica exchange molecular dynamics (REMD) simulations have been used to model the IgG1 protein tethered onto the amorphous silica surface by considering a united-atom model and a relatively large system (2500 nm² surface). Additional molecular dynamics (MD) simulations have been conducted to derive an atomistic model for the amorphous silica surface using the cristobalite crystal structure as a starting point and to examine the structure of the free IgG1 antibody in the solution for comparison when immobilized. Analyses of the trajectories obtained for the tethered IgG1, which was sampled considering 32 different temperatures, have been used to define the geometry of the protein with respect to the inorganic surface. The tilt angle of the protein with respect to the surface plane increases with temperature, the most populated values being 24, 66, and 87° at the lowest (250 K), room (298 K), and the highest (380 K) temperatures. This variation indicates that the importance of protein-surface interactions decreases with increasing temperature. The influence of the surface on the structure of the antibody is very significant in the constant region, which is directly involved in the tethering process, while it is relatively unimportant for the antigen-binding fragments, which are farthest from the surface. These results are expected to contribute to the development of improved mechanical-plasmonic sensor microarrays in the near future.

Intravenous iron infusion as an alternative to minimize blood transfusion in peri-operative patients

Despite the reported benefits of intravenous iron therapy (IVIT) for correcting iron deficiency anemia (IDA) before any major surgery and the evidence thereof, perioperative allogenic blood transfusion (ABT) practice is still considered as the only viable option by some clinicians worldwide. As ABT increases the likelihood of infections, cardiac complications, longer hospital stays and mortality among the patients, the practice of ABT should only be reserved for critical cases (Hb level < 7 g/dl). Timely iron studies and iron replenishment (oral/IV) of prospective surgical patients could help decrease the ABT practice, and prove beneficial from both the clinical and economic standpoint. Evidence based patient blood management guidelines should be developed and standardized for use by clinicians worldwide. These guidelines should include specific instructions on timely assessment of surgical patients for correction of their IDA by either oral iron supplementation, if time permits, or by using IVIT such as ferric carboxymaltose (FCM) in emergency surgeries and in patients with functional ID. This study was conducted to explore the clinical benefits of the timely administration of IV-FCM in iron-deficient preoperative patients during 2017-2018 and compare the results thereof with that of the ABT. Based on the IDA treatment plan of 2953 patients, 11.14% cases were administered IV FCM (Group 1), 11.58% cases received ABT (Group 2), while the remaining 77.27% of anemic cases received neither ABT nor IV FCM (Group 3). The results indicate that the IV FCM administration reduces the need for ABT and thus minimizes its associated side effects. The findings of our study concur with the favorable outcomes reported by the other similar studies.

Accelerated approval of Oxbryta® (voxelotor): A case study on novel endpoint selection in sickle cell disease

Sickle cell disease (SCD) is an inherited disease characterized by hemolysis, anemia, and vaso-occlusion leading to substantial morbidity and mortality. Development of prior pharmacologic therapies exclusively utilized vaso-occlusive crisis (VOC) as a clinical efficacy endpoint; however, this focus on VOC did not capture the full extent of disease symptomatology and complications and slowed the development of new therapies. Voxelotor, a hemoglobin S polymerization inhibitor, was recently approved in the United States for the treatment of SCD in adults and adolescents 12 years of age and older through an accelerated approval pathway. The rapid approval and availability of voxelotor was facilitated in a collaborative effort with the US Food and Drug Administration (FDA), using hemoglobin, a biologic surrogate endpoint, as reasonably likely to predict clinical benefit. Use of this new endpoint was supported by FDA-led multistakeholder discussions with physician and patient communities to identify unmet needs and potential clinical trial endpoints, as well as by a company-sponsored analysis of external patient-level data to demonstrate a correlation between hemoglobin change and stroke risk. A two-part phase 3 study was used to allow for rank ordering of key secondary endpoints based on a planned interim analysis. Continued open communication with the FDA was essential to gain agreement on hemoglobin as a novel endpoint and to address the unmet and urgent need of new therapies for SCD.

RBC Transfusion Triggers: Is There Anything New?

For many years, in daily clinical practice, the traditional 10/30 rule (hemoglobin 10 g/dL - hematocrit 30%) has been the most commonly used trigger for blood transfusions. Over the years, this approach is believed to have contributed to a countless number of unnecessary transfusions and an unknown number of overtransfusion-related deaths. Recent studies have shown that lower hemoglobin levels can safely be accepted, even in critically ill patients. However, even these new transfusion thresholds are far beyond the theoretical limits of individual anemia tolerance. For this reason, almost all publications addressing the limits of acute anemia recommend physiological transfusion triggers to indicate the transfusion of erythrocyte concentrates as an alternative. Although this concept appears intuitive at first glance, no solid scientific evidence supports the safety and benefit of physiological transfusion triggers to indicate the optimal time point for transfusion of allogeneic blood. It is therefore imperative to continue searching for the most sensitive and specific parameters that can guide the clinician when to transfuse in order to avoid anemia-induced organ dysfunction while avoiding overtransfusion-related adverse effects. This narrative review discusses the concept of anemia tolerance and critically compares hemoglobin-based triggers with physiological transfusion for various clinical indications.

Red blood cell prescription and recognition of transfusion reactions by pediatricians

Objective

To assess the level of knowledge of emergency pediatricians on red blood cell transfusions and their reactions.

Methods

Written survey with emergency pediatricians from a pediatric hospital.

Results

Less than 20% of pediatricians showed appropriate knowledge on prescribing red blood cells and recognition of transfusion reactions. There was no significant statistical regarding time since graduation and blood transfusion classes in undergraduate studies or during medical residency.

Conclusion

Pediatricians have insufficient knowledge about red blood cell transfusions and recognition of transfusion reactions.

Objective assessment of stored blood quality by deep learning

Stored red blood cells (RBCs) are needed for life-saving blood transfusions, but they undergo continuous degradation. RBC storage lesions are often assessed by microscopic examination or biochemical and biophysical assays, which are complex, time-consuming, and destructive to fragile cells. Here we demonstrate the use of label-free imaging flow cytometry and deep learning to characterize RBC lesions. Using brightfield images, a trained neural network achieved 76.7% agreement with experts in classifying seven clinically relevant RBC morphologies associated with storage lesions, comparable to 82.5% agreement between different experts. Given that human observation and classification may not optimally discern RBC quality, we went further and eliminated subjective human annotation in the training step by training a weakly supervised neural network using only storage duration times. The feature space extracted by this network revealed a chronological progression of morphological changes that better predicted blood quality, as measured by physiological hemolytic assay readouts, than the conventional expert-assessed morphology classification system. With further training and clinical testing across multiple sites, protocols, and instruments, deep learning and label-free imaging flow cytometry might be used to routinely and objectively assess RBC storage lesions. This would automate a complex protocol, minimize laboratory sample handling and preparation, and reduce the impact of procedural errors and discrepancies between facilities and blood donors. The chronology-based machine-learning approach may also improve upon humans' assessment of morphological changes in other biomedically important progressions, such as differentiation and metastasis.

Large-scale in vitro production of red blood cells from human peripheral blood mononuclear cells

Transfusion of donor-derived red blood cells (RBC) is the most common form of cellular therapy. Donor availability and the potential risk of alloimmunization and other transfusion-related complications may, however, limit the availability of transfusion units, especially for chronically transfused patients. In vitro cultured, customizable RBC would negate these concerns and further increase precision medicine. Large-scale, cost-effective production depends on optimization of culture conditions. We developed a defined medium and adapted our protocols to good manufacturing practice (GMP) culture requirements, which reproducibly provided pure erythroid cultures from peripheral blood mononuclear cells without prior CD34+ isolation, and a 3 × 107-fold increase in erythroblasts in 25 days (or from 100 million peripheral blood mononuclear cells, 2 to 4 mL packed red cells can be produced). Expanded erythroblast cultures could be differentiated to CD71dimCD235a+CD44+CD117-DRAQ5- RBC in 12 days. More than 90% of the cells enucleated and expressed adult hemoglobin as well as the correct blood group antigens. Deformability and oxygen-binding capacity of cultured RBC was comparable to in vivo reticulocytes. Daily RNA sampling during differentiation followed by RNA-sequencing provided a high-resolution map/resource of changes occurring during terminal erythropoiesis. The culture process was compatible with upscaling using a G-Rex bioreactor with a capacity of 1 L per reactor, allowing transition toward clinical studies and small-scale applications.

[Prevalence of sickle cell trait in blood donors at the regional blood transfusion center in the Haute Matsiatra Region, Madagascar]

INTRODUCTION

sickle cell trait is the heterozygous form of sickle-cell disease. Patients with sickle cell trait can synthesize normal hemoglobin A and hemoglobin S. This condition has no recognizable clinical signs; then subjects with sickle cell trait, ignoring their genetic status, can be found among blood donors. This can have severe impact on donors´ health status and on that of recipients, especially if these have sickle-cell trait. The purpose of our study is to determine the prevalence of sickle cell trait in blood donors.

METHODS

we conducted a 4-month descriptive prospective study (January-May 2017) at the Haute Matsiatra Regional Blood Transfusion Center (RBTC). All donors were screened by Emmel test and positive cases were confirmed by hemoglobin electrophoresis.

RESULTS

the study involved 427 donors, of whom 332 were men and 95 women (sex ratio 3.4). The average age of blood donors was 32.72, ranging from 18 to 64 years. Emmel test was positive in 5 donors (1.17%). These patients had the AS genotype confirmed by hemoglobin electrophoresis.

CONCLUSION

the results of this study reveal the presence of sickle cell trait among blood donors at the CRTS. Most of them ignore their sickle cell status before blood donation. Quality and safety of blood and blood products are mandatory, hence the importance of screening among blood donors is a current relevant issue.

Red blood cell and platelet transfusion support in the first 30 and 100 days after allogeneic hematopoietic cell transplant

BACKGROUND

Allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients often require substantial but variable transfusion support.

STUDY DESIGN AND METHODS

This single-center, retrospective study evaluated the red blood cell (RBC) and platelet (PLT) transfusion data of first-time allo-HSCT recipients transplanted in 2011 to 2017. Multivariate analyses were performed to assess the associations between patient and transplant-related factors and transfusion requirements.

RESULTS

The study included 1762 patients who received peripheral blood stem cells (88.2%), marrow (7.0%), or umbilical cord (4.8%) from matched related (38.3%), unrelated (49.2%), or haploidentical (7.8%) donors. Almost all patients required RBCs (88.3%) or PLTs (97.4%) during the first 30 days, with medians of 3 (range, 1-37) RBC and 6 (range, 1-144) PLT units transfused. Fewer patients required RBC (43.8%) or PLT (27.3%) transfusions during Days 31 to 100, but the median (range) numbers of RBC and PLT units remained high at 3 (1-36) and 6 (1-116) among transfused patients. RBC and PLT transfusion independence was reached in medians of 24 (95% confidence interval [CI], 22-26) and 12 (95% CI, 11-12) days, respectively. Haploidentical donor, cord graft, and requiring RBC transfusions in the 10 days before HSCT were the most significant independent factors predictive of increased transfusion requirements. Advanced disease, diagnosis, ABO incompatibility, conditioning intensity, CD34+ cell dose, presence of severe acute graft-vs-host disease, and changes in recommended transfusion triggers were also shown to independently impact transfusion requirements.

CONCLUSIONS

This study provided for the first time quantitative and comparative transfusion data on a large contemporary cohort of HSCT recipients, including haploidentical and cord graft recipients, and identified factors predictive of increased transfusions.

Expert consensus on interventional therapy for traumatic splenic bleeding

This study aims to introduce the diagnosis and treatment processes of traumatic splenic bleeding and explain its emergency, medical, interventional, and surgical treatments. Furthermore, this study aims to summarize the indications and contraindications of splenic artery embolization, interventional procedures, and precautions of complications.

Electronic clinical decision support to facilitate a change in clinical practice: Small details can make or break success

BACKGROUND

The use of electronic clinical decision support (CDS) is becoming common to change historically common clinical practices considered outdated by current guidelines. Preimplementation design of CDS tools is key to their success in changing clinical behaviors. Unfortunately, there are no established protocols for CDS tool development, and CDS failure can result from even small design flaws. This paper describes an example of a design oversight and how correction resulted in CDS success.

STUDY DESIGN AND METHODS

We performed a retrospective review of compliance with a CDS tool to encourage the use of prothrombin complex concentrate over plasma transfusion for the emergent reversal of warfarin. We identified a potential design flaw, made the necessary modifications, and repeated the compliance review.

RESULTS

After CDS, plasma orders declined by 150 units/mo; however, 48% of orders placed for non-warfarin coagulopathy were still for warfarin reversal. Hospital-wide, this noncompliance was 36% and was 80% in the emergency department. By simply relocating the qualifier "NOT on warfarin" from the end to the beginning of the order, noncompliance for warfarin reversal was reduced to 5% (P < .0001 by chi-square).

CONCLUSIONS

The successful use of electronic clinical decision support in the electronic medical record can depend on optimal design. Missing even small design elements such as the positioning of key terms within the tool can result in an ineffective CDS. Important design strategies to avoid poor performance are discussed as they relate to the CDS tool we describe.

Massive transfusion protocol in adult trauma population

BACKGROUND

Acute blood loss in trauma requires quick identification and action to restore circulating volume and save the patient. Massive transfusion protocols (MTPs) have become standard at Trauma Centers, in order to rapidly deliver blood products to bleeding patients. This literature review presents current standards of transfusion ratios, as well as insights into adjuncts during massive transfusions.

METHODS

PubMED was searched for articles from 2005 to 2020 on MTPs, the article were assessed for single vs. multi-institutional, mechanism of injury, type of MTP, timing in which blood products should be administered, timing of delivery of blood products to trauma bay, pre-hospital treatment and adjuncts, and outcomes.

RESULTS

Eleven studies addressed transfusion ratios. Seven studies looked at timing of blood products. Nine studies addressed MTP pre-hospital treatment and adjuncts. Prior to 2015, studies supported the benefits of a balanced transfusion ratio, which was then confirmed by the PROPPR randomized controlled trial. The shorter the time to blood product delivery the better the outcomes. New advances in technology have allowed us to measure different patterns of coagulation, allowing more individualized approaches to the bleeding patient.

CONCLUSION

Current massive transfusion protocols should utilize between 1:1:1 and 1:1:2 ratios of the 3 main products; plasma, platelets, and red blood cells. Massive transfusion protocols are effective in decreasing mortality. Better resuscitation efforts were seen when blood products were readily available in the trauma bay when the patient arrived and the faster the replacement of blood, the better the outcomes.

Impact of perioperative blood transfusion on survival in pancreatic neuroendocrine tumor patients: analysis from the US Neuroendocrine Study Group

BACKGROUND

Packed red blood cell (PRBC) transfusion has been associated with worse survival in multiple malignancies but its impact on pancreatic neuroendocrine tumors (PNETs) is unknown. The aim of this study was to determine the impact of PRBC transfusion on survival following PNET resection.

METHODS

A retrospective cohort study of PNET patients was performed using the US Neuroendocrine Tumor Study Group database. Demographic and clinical factors were compared. Kaplan-Meier and log-rank analyses were performed. Factors associated with transfusion, overall (OS), recurrence-free (RFS) and progression-free survival (PFS) were assessed by logistic regression.

RESULTS

Of 1129 patients with surgically resected PNETs, 156 (13.8%) received perioperative PRBC transfusion. Transfused patients had higher ASA Class, lower preoperative hemoglobin, larger tumors, more nodal involvement, and increased major complications (all p < 0.010). Transfused patients had worse median OS (116 vs 150 months, p < 0.001), worse RFS (83 vs 128 months, p < 0.01) in curatively resected (n = 1047), and worse PFS (11 vs 24 months, p = 0.110) in non-curatively resected (n = 82) patients. On multivariable analysis, transfusion was associated with worse OS (HR 1.80, p = 0.011) when controlling for TNM stage, tumor grade, final resection status, and pre-operative anemia.

CONCLUSION

PRBC transfusion is associated with worse survival for patients undergoing PNET resection.

Optimisation and control of the supply of blood bags in hemotherapic centres via Markov decision process with discounted arrival rate

Running a cost-effective human blood transfusion supply chain challenges decision makers in blood services world-wide. In this paper, we develop a Markov decision process with the objective of minimising the overall costs of internal and external collections, storing, producing and disposing of blood bags, whilst explicitly considering the probability that a donated blog bag will perish before demanded. The model finds an optimal policy to collect additional bags based on the number of bags in stock rather than using information about the age of the oldest item. Using data from the literature, we validate our model and carry out a case study based on data from a large blood supplier in South America. The study helped achieve an overall increase of 4.5% in blood donations in one year.

Risk factors for hemolytic transfusion reactions resulting from ABO and minor red cell antigen incompatibility: From mislabeled samples to stem cell transplant and sickle cell disease

Advances in laboratory testing, pathogen reduction and donor qualification have dramatically reduced the risk of acquiring an infection from a blood transfusion. Despite this progress, the most feared complication of transfusion - a hemolytic reaction due to incompatibility between donor and recipient - remains, with essentially no recent progress in the prevention or recognition of this rare but frequently lethal complication. Herein, the role that compatibility testing and transfusion practice play in the occurrence of acute hemolysis are described, with a special emphasis on clinical scenarios confer an increased risk of a severe hemolytic reaction in response to red blood cell or platelet transfusion. In addition, the signs and symptoms of a severe hemolytic reaction are summarized, along with the initial approach to clinical management.

Preparation of packed red blood cell units in the blood bank: Alteration in red blood cell deformability

BACKGROUND

Donated blood is stored in the blood bank as packed red blood cell units. In the process of packed cells preparation, the red blood cells (RBCs) are subjectedto high level of shear stress, which can induce alterations in their properties. In the present study, we examined the effect of packed RBCs preparation (which included leuko-filtration) on red cell deformability.

METHODS

Blood samples were collected from 25 healthy donors and from corresponding units of packed RBCs. The portion of undeformable cells (%UDFC) was determined for each sample.

RESULTS

The median value of %UDFC was equal to 6.75 ± 0.70 %, for freshly-donated RBCs, and to 6.36 ± 0.51 %, for packed cells. Wherein, %UDFC may increase or decrease following packed cells preparation, depending upon the initial portion of undeformable cells.

CONCLUSION

Likely, exposure of RBCs to high shear stress, during packed cells preparation, induces opposing effects: (a) removal/destruction of rigid (undeformable) cells, thereby reducing their total amount (i.e., decreasing the %UDFC) on the one hand, and (b) mechanical damage to the cell membrane and subsequent reduction of the cell deformability (thereby increasing the %UDFC) on the other. As a consequence, the final impact of packed cells preparation is primarily determined by the initial state of erythrocytes in the blood of the donor.

Physiological and microvascular responses to hemoglobin concentration-targeted hemolytic anemia in rats

Hemolytic anemia (HA) is reduced blood oxygen-carrying capacity resulting from the depletion of red blood cells. Treatment for severe cases involves transfusion to improve oxygen delivery (Do₂), which carries risk. In humans, a total hemoglobin (tHb) concentration of 8 g/dL is severe, and <7 g/dL indicates transfusion. Some evidence suggests that compensatory mechanisms maintaining Do₂ are not compromised until <5 g/dL rendering transfusion at 7 g/dL premature. A Sprague-Dawley rat model of phenylhydrazine-induced HA was assessed over decreasing tHb for a Do₂ decompensation point. Three groups (100, 50, or 25% tHb, equating to 16.4, 7.4, or 3.2 g/dL) were generated. Cardiopulmonary, blood chemistry, and oxygenation parameters were measured under anesthesia. Vasoconstrictive responsiveness to phenylephrine was assessed in the exteriorized spinotrapezius. For 50% tHb, cardiopulmonary parameters, Do₂, and lactate levels were similar to those for 100% tHb. Enhanced vasoconstriction occurred with 50% tHb (P < 0.0001), not 25% tHb. The 25% group showed decreases in cardiopulmonary parameters, Do₂, and lactate levels compared with the 100% and 50% groups (P < 0.05). Do₂ showed a positive correlation with lactate levels at 25% tHb, but decompensation, defined by peripheral hypoxia, was not reached. This is the first study relating Do₂ to tHb in rats. A 50% reduction in tHb was supported by vascular compensation, whereas 25% tHb levied the cardiopulmonary system. A decompensation point was not identified. A rising need for treatment as tHb levels decline below 8 g/dL is evident, but, as compensatory mechanisms remain intact as tHb approaches 3.2 g/dL in rats, a transfusion limit of 5 g/dL in healthy patients is supported.NEW & NOTEWORTHY Early, chronic compensation to severe hemolytic anemia is vascular, switching to cardiopulmonary support as hemoglobin levels decline. Oxygen delivery does not correlate with serum lactate level until total hemoglobin is reduced by 75%.

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

OBJECTIVE

To identify to what extent distinguishing patient and procedural characteristics can explain center-level transfusion variation during coronary artery bypass grafting surgery.

METHODS

Observational cohort study using the Perfusion Measures and Outcomes Registry from 43 adult cardiac surgical programs from July 1, 2011, to July 1, 2017. Iterative multilevel logistic regression models were constructed using patient demographic characteristics, preoperative risk factors, and intraoperative conservation strategies to progressively explain center-level transfusion variation.

RESULTS

Of the 22,272 adult patients undergoing isolated coronary artery bypass surgery using cardiopulmonary bypass, 7241 (32.5%) received at least 1 U allogeneic red blood cells (range, 10.9%-59.9%). When compared with patients who were not transfused, patients who received at least 1 U red blood cells were older (68 vs 64 years; P < .001), were women (41.5% vs 15.9%; P < .001), and had a lower body surface area (1.93 m² vs 2.07 m²; P < .001), respectively. Among the models explaining center-level transfusion variability, the intraclass correlation coefficients were 0.07 for model 1 (random intercepts), 0.12 for model 2 (patient factors), 0.14 for model 3 (intraoperative factors), and 0.11 for model 4 (combined). The coefficient of variation for center-level transfusion rates were 0.31, 0.29, 0.40, and 0.30 for models 1 through 4, respectively. The majority of center-level variation could not be explained through models containing both patient and intraoperative factors.

CONCLUSIONS

The results suggest that variation in center-level red blood cells transfusion cannot be explained by patient and procedural factors alone. Investigating organizational culture and programmatic infrastructure may be necessary to better understand variation in transfusion practices.

Administration of Tranexamic Acid in Proximal Humeral Fractures

INTRODUCTION

This study aimed to analyze the efficacy of intravenous administration of tranexamic acid in complex proximal humeral fractures.

MATERIALS AND METHODS

Sixty-seven patients with displaced 3 and 4 part proximal humerus fractures were randomized into the control (n = 33) and TXA (n = 34) groups. Fifteen minutes before the skin incision, 15 mg/kg body weight of 0.9% sodium chloride solution or TXA was injected intravenously. Open reduction and internal fixation was conducted through a deltoid-pectoral approach with fixed angle locked plating (PHILOS) for all the patients. The patients were followed up 2 months after surgery. Total blood loss, blood test results, blood transfusion rate, and wound complications were analyzed between the two groups.

RESULTS

Significant differences were observed in intraoperative blood loss and postoperative blood loss during the first 24 h between the two groups. There were no significant differences in postoperative blood loss during the second 24 h, wound complication rates, blood transfusion rate and adverse side effects. And thromboembolic events related with the application of TXA were not noted in the TXA group.

CONCLUSION

Preoperative administration of tranexamic acid could reduce intraoperative and postoperative blood loss in patients with complex proximal humeral fractures.

LEVEL OF EVIDENCE

II, prospective comparative study.

Early and sustained improvement in fatigue-related quality of life following red blood cell transfusion in outpatients

PURPOSE

Outpatients with hematologic disease often receive red cell transfusion to treat anemia and fatigue. The effect of transfusion on fatigue-related quality of life and how well this effect is sustained has not been quantified. The study aim was to describe the early and sustained impact over 4 weeks of red cells on patient-reported fatigue in outpatients age ≥ 50 receiving transfusion as routine clinical care.

METHODS

FACIT-Fatigue scale scores were measured pre-transfusion and at visits targeting 3, 7, and 28 days post-transfusion. Group-based trajectory modeling of patient fatigue scores by study day was used to identify the number of distinct trajectories (Groups), then longitudinal mixed effects modeling of fatigue scores was used to estimate group-specific mean improvements early after transfusion and between days 3 and 28 post-transfusion.

RESULTS

Four distinct fatigue score trajectory groups were identified and were found to be correlated with baseline fatigue scores (means 12, 26, 34, and 47 points). In the three groups with the lowest fatigue trajectories (indicating greater fatigue), improvements in fatigue early after transfusion achieved the established minimum clinically important difference (≥ 3 points, Group p = 0.0039). In all trajectory groups, mean fatigue levels did not change significantly between 3 and 28 days (± 1 point, Group p = 0.60).

CONCLUSION

Patient-reported fatigue varies widely among older adult outpatients with hematologic disorders. Nonetheless, trajectory modeling suggests that most anemic patients can expect a noticeable improvement in fatigue in the first few days after transfusion that generally is sustained up to 4 weeks.

Does Intra-Wound Vancomycin Powder Affect the Action of Intra-Articular Tranexamic Acid in Total Joint Replacement?

The intra-articular use of tranexamic acid (TXA) has contributed to reduced blood loss in total joint arthroplasty (TJA). The purpose of this study is to assess the efficacy of simultaneously topical use of tranexamic acid and vancomycin powder within the TJA space. From 2016 to 2017, 219 consecutive total hip arthroplasties (THAs) and 272 total knee arthroplasties (TKAs) were performed in a tertiary care center, with a group of patients receiving intra-articular TXA and vancomycin, compared to patients receiving only TXA and to a control group that did not receive anything. Haemoglobin and hematocrit were measured preoperatively, on the first and third days. Transfusions and adverse events were recorded. Haemoglobin and hematocrit dropped significantly in all THA and TKA groups till the third day postoperatively, with a major reduction in the control group, compared to the other two treatment groups. Infections and thromboembolic events were similar in either group of the TJAs. In conclusion, the topical use of tranexamic acid mixed with the vancomycin powder within the joint space after the TJAs of the hip and knee did not alter the anti-fibrinolytic effect of TXA.

A case study of 10 patients administered HBOC-201 in high doses over a prolonged period: outcomes during severe anemia when transfusion is not an option

BACKGROUND

Hemoglobin-Based Oxygen Carriers (HBOCs) can act as an "oxygen bridge" in acute severe anemia when transfusion is indicated, but not possible. We present data on 10 Expanded Access (EA) patients treated with high cumulative doses of Hemopure (HBOC-201), to assess the ability of HBOC-201 to safely treat life threatening anemia in situations where high volumes of product were administered over an extended period of time.

STUDY DESIGN AND METHODS

Inclusion in this study required that the patient receive at least 10 units of HBOC-201 between 2014 and 2017 under the FDA-sanctioned EA program. Depending on a patient's geographical location, treatment with HBOC-201 was obtained through either a single patient emergency Investigational New Drug (IND) application, or an intermediate size population IND. Of the 41 patients who were treated during this period, 10 patients received 10 or more units of the product. Data were obtained from medical records.

RESULTS

Treatments with HBOC-201 started within 24 hours of signing consent and were administered at an average rate of 1.99 (SD 0.17) units per day over a mean of 8.2 days (SD 2.9), during which patients received on average 16.2 units (SD 5.7 units) of HBOC-201. The median pre-treatment nadir corpuscular hemoglobin (Hb) concentration was 3.3 (SD 0.9) g/dL and post-treatment Hemoglobin was 7.3 (SD 1.7) g/dL. Common side effects included methemoglobinemia, gastrointestinal symptoms, and hypertension. However, no product-related serious adverse events (SAEs) were noted. All patients survived.

CONCLUSIONS

Administration of HBOC-201 over an extended period is a feasible and safe oxygen bridge for severely anemic patients who cannot be transfused with RBC.

Bleeding Risk Associated With Hemodynamically Stable Low-Energy Pelvic Fracture

Introduction:

Life-threatening hemorrhage associated with low-energy pelvic fracture has been described in single cases in the literature. However, there is limited evidence available on the bleeding risk associated with hemodynamically stable osteoporotic pelvic fractures. The objective of this study was to estimate the bleeding risk associated with low-energy osteoporotic pelvic fractures in the elderly population.

Materials and Methods:

A retrospective review of patients aged > 65 years old with pelvic fractures admitted between 2015 and 2018 was performed. Eighty-two patients were identified: 12 males and 70 females with a median age of 86 years. The median Charlson comorbidity index was 6 (interquartile range = 5-7). Eighty-one fractures were classified as lateral compression I or Tile A2, and 1 fracture was classified as lateral compression II or Tile B2. Forty patients were on concurrent anticoagulation treatment. In 4 patients on warfarin, this treatment was reversed on admission.

Results:

The mean hemoglobin (Hb) level on arrival was 12.36 g/dL (±1.67 g/dL). There were significant drops in Hb levels on day 1 (Hb = 11.22 ± 1.86 g/dL, P < .001) and day 4 (Hb = 10.97 ± 1.6 g/dL, P < .001). Nine percent of patients required a blood transfusion. The mean baseline Hb level pre-transfusion was 8.33 g/dL (±1.15). Preexisting anticoagulation treatment did not predispose patients to greater decreases in Hb levels on day 1 (mean difference = 0.16 g/dL, P = .62) or day 4 (mean difference = 0.29 g/dL, P = .48) post-admission.

Discussion:

An observed mean decrease in Hb level of up to 1.4 g/dL can occur in hemodynamically stable elderly patients with osteoporotic pelvic fractures, reflecting an approximate loss of 1.4 units of packed red blood cells.

Conclusion:

This degree of decrease in Hb may be clinically significant in geriatric patients with chronic anemia and a history of cardiovascular disease.

Liberal Transfusion versus Restrictive Transfusion and Outcomes in Critically Ill Adults: A Meta-Analysis

Objective

We aimed to determine whether the restrictive red-cell transfusion strategy was superior to the liberal one in reducing all-cause mortality in critically ill adults.

Methods

The MEDLINE, EMBASE, PubMed, Web of Science, and Cochrane Library Central Register of Controlled Trials databases were searched from inception to January 2019 to identify meta-analyses or systematic reviews and published randomized controlled trials which were restrictive versus liberal blood transfusion with mortality as the endpoint in critically ill adults. We used two search routes whereby one search was restricted to systematic reviews, reviews, or meta-analysis, and the other was not restricted. There were no date restrictions, but language was limited to English and the population was restricted to critically ill adults. The data of study methods, participant characteristics, and outcomes were extracted and analyzed independently by 2 reviewers. The main outcome was all-cause mortality.

Results

Through screening the obtained records, we enrolled 7 randomized clinical trials that included information on restrictive versus liberal red-cell transfusion and mortality of intensive care unit (ICU) patients. Involving a total of 7,363 ICU adult patients, ICU mortality (risk ratio [RR] 0.82, 95% confidence interval [CI] 0.62, 1.08, p = 0.15), 28/30-day mortality (RR 0.98, 95% CI 0.84, 1.13, p = 0.74), 60-day mortality (RR 1.01, 95% CI 0.87, 1.16, p = 0.91), 90-day mortality (RR 1.02, 95% CI 0.92, 1.14, p = 0.69), 120-day mortality (RR 1.29, 95% CI 0.67, 2.47, p = 0.44), and 180-day mortality (RR 0.91, 95% CI 0.75, 1.12, p = 0.38) were not statistically significantly different when the restrictive transfusion strategy was compared with the liberal transfusion strategy. However, we surprisingly discovered that 112 out of 469 (24%) patients who received a unit RBC transfusion when hemoglobin was less than 7 g/dL, and 142 out of 469 (30.3%) who received a unit of RBC transfused with hemoglobin less than 9 g/dL, had died during hospitalization (RR 0.79, 95% CI 0.64, 0.97, p = 0.03). The results showed that the restrictive transfusion strategy could decrease in-hospital mortality compared with the liberal transfusion strategy. It was safe to utilize a restrictive transfusion threshold of less than 7 g/dL in stable critically ill adults.

Conclusions

In this study, we found that the restrictive red-cell transfusion strategy potentially reduced in-hospital mortality in critically ill adults with anemia compared with the liberal strategy.

Rejuvenation solution as an adjunct cold storage solution maintains physiological haemoglobin oxygen affinity during early-storage period of red blood cells

BACKGROUND

Red blood cell (RBC) units accumulate morphologic and metabolic lesions during storage before transfusion. Pyruvate-inosine-phosphate-adenine (PIPA) solutions (Rejuvesol, Biomet, Warsaw, IN) can be incubated with RBC units to mitigate storage lesions. This study proposes a PIPA treatment process, termed cold 'rejuvenation', using Rejuvesol as an adjunct additive solution, to prevent biomechanical storage lesions while avoiding the 1 h PIPA incubation required with standard PIPA treatment. We compared the efficacy of cold to standard 'rejuvenation' in improving metabolic lesions that occur during cold storage of RBCs, without altering function.

METHODS

Twelve leucoreduced, A-positive RBC units were obtained. Each unit was aliquoted into either control (standard storage), washed (W), standard rejuvenation (SR) or cold rejuvenation (CR) groups, the latter two requiring washing. A volume-adjusted dose of Rejuvesol was instilled into the CR group upon receipt (Day 3). After 15 days of storage, p50, RBC deformability, in-bag haemolysis and mechanical fragility were analysed. 'Any treatment' is defined as W, SR and CR, with comparisons in reference to control.

RESULTS

Higher p50s were seen in rejuvenated groups (>30 mmHg vs. <19 mmHg; P < 0·0001). Any treatment significantly increased elongation index (P = 0·034) but did not significantly increase in-bag haemolysis (P = 0·062). Mechanical fragility was not significantly different between groups (P = 0·055) at baseline, but the control (CTL) group was more fragile after 2 h in a cardiac bypass simulation than any treatment (P < 0·0001).

CONCLUSIONS

This study demonstrates that rejuvenation (standard or cold) prevents the leftward p50 shift of storage lesions without detrimental effect on RBC deformity, in-bag haemolysis or mechanical fragility.

Prevention strategies of transfusion-transmitted parasitic infections (TTPIs): Strengths and challenges of current approaches, and evaluation of the strategies implemented in Iran

Background

Several strategies are being implemented in blood transfusion centers of the world to prevent the transfusion-transmitted parasitic infections (TTPIs). The objective of this study was to determine and describe the strategies to minimize the transmission risk of parasitic agents via blood transfusion in Iran.

Methods

This study was conducted in the Iranian blood transfusion organization (IBTO). The data were extracted from the latest version of the “medical interview” standard operating procedure (SOP).

Results

The donor selection is the first and only step to reduce the risk of TTPIs in endemic and non-endemic areas of Iran. In all blood transfusion centers of the IBTO, the blood donation volunteers with a previous history of malaria, Chagas disease, visceral leishmaniasis (VL), muco-cutaneous leishmaniasis and babesiosis, as well as those with clinical toxoplasmosis, cutaneous leishmaniasis (CL) and with a history of residence in, or travel to, malaria-endemic areas are permanently or temporarily deferred from the blood donation.

Conclusions

Since malaria, toxoplasmosis and VL are endemic in parts of Iran, as well as the increasing travels to endemic areas and immigrations from endemic to non-endemic areas of parasitic infections, the extensive use of blood and blood components and the asymptomatic occurrence of most parasitic infections in blood donors, the donor selection strategy is not sufficient to prevent the TTPIs. Therefore, the changing of donor selection process and the use of other common preventive strategies are recommended to reduce the risk of TTPIs, especially for high-risk groups of toxoplasmosis and VL.

Development of Humanized Ossicles: Bridging the Hematopoietic Gap

Ectopic 'humanized ossicles' (hOss) are miniaturized, engineered human bone organs in mice displaying a similar structure and function to native mouse bones. However, they are composed of human mesenchymal derived cells forming a humanized bone marrow niche. This in vivo reconstitution of human skeletal and hematopoietic compartments provides an opportunity to investigate the cellular and molecular processes involved in their establishment and functions in a human setting. However, current hOs strategies vary in their engineering methods and their downstream applications, undermining comprehensive exploitation of their potential. This review describes the specificities of the hOs models and highlights their potential and limits. Ultimately, we propose directions for the development of hOss as a technological platform for human hematopoietic studies.