Evidence-Based Red Blood Cell Transfusion Practices in Cardiac Surgery

Cardiac surgical patients are among the highest consumers of allogeneic red blood cells (RBCs) due to the prevalence of anemia and bleeding. Up until recently, there was a paucity of high-quality evidence informing transfusion decisions in this patient group which led to wide variability in transfusion decision making. The article reviews and critically analyzes the available evidence for RBC transfusion in cardiac surgery, focusing on trials of transfusion triggers and age of blood, and provides suggestions for future research. Observational studies analyzing outcomes in patients transfused vs those not transfused have consistently shown RBC transfusion to be associated with adverse outcomes. However, multiple sources of bias in these studies invalidate their conclusions. The best available evidence comes from randomized controlled trials which compare liberal vs restrictive transfusion thresholds. To date, 6 randomized controlled trials have been reported in cardiac surgical patients, and pooled analyses have shown no differences in clinical outcomes between the 2 strategies. Similarly, research into age of RBCs and adverse outcomes has failed to demonstrate a pathological effect attributable to the storage lesion; the recent multicenter Red Cell Storage Duration Study (RECESS) trial has demonstrated no difference in outcomes between patients receiving fresh or old RBCs. Future research needs to identify what a safe transfusion threshold may be, and how this differs for different patient groups and different stages of the perioperative journey. There is also a need to evaluate other physiological parameters which, coupled with hemoglobin concentration, can better inform those patients who need an RBC transfusion.     

Regional Oxygenation and Perfusion Monitoring to Optimize Neonatal Packed Red Blood Cell Transfusion Practices: A Systematic Review

Contemporary packed red blood cell transfusion practices in anaemic preterm infants are primarily based on measurement of hemoglobin or haematocrit. In neonatal intensive care units, most preterm infants receive at least 1 packed red cell transfusion as standard treatment for anaemia of prematurity. Clinicians are faced with a common question “at what threshold should anaemic preterm infants receive packed red blood cell transfusion?”. While evidence from interventional trials offers a range of haemoglobin levels to clinicians on thresholds to initiate red cell transfusion, it does not offer identification of exact haemoglobin level at which regional oxygenation and perfusion gets compromised. Assessment of regional oxygenation using near infrared spectroscopy and perfusion using ultrasound could offer a personalized transfusion medicine approach to optimize transfusion practices. We conducted a systematic review of the literature to identify the role of both regional oxygenation and/or ultrasound-based perfusion monitoring as a potential trigger to initiate packed red blood cell transfusion in anaemic preterm infants. MEDLINE, Embase, Maternity and Infant Care database were searched up to March 2021. Publications identified were screened and relevant data was extracted. Changes to regional oxygenation and/or perfusion monitoring before and after packed red blood cell transfusion were the primary outcomes. 44 out of 755 studies met the inclusion criteria and were included in the final analysis. Most were prospective, observational studies in stable preterm infants. Overall, studies reported an improvement in regional oxygenation and/or ultrasound-based perfusion after packed red blood cell transfusion. These changes were more consistently observed when hemoglobin <9.6g/dL or hematocrit was <0.30. Significant variation was found for patient characteristics, postnatal age at the time of monitoring, criteria for diagnosis of anaemia, and period of monitoring as well as regional oxygenation monitoring methodology. Regional oxygenation and/or perfusion monitoring can identify at-risk anaemic preterm infants and are promising tools to individualize packed red blood cell transfusion practices. However, there is lack of evidence for incorporating this monitoring, in their present form, into standard clinical practice. Additionally, consistency in reporting of study methodology should be improved.     

Efficacy and Safety of Tranexamic Acid in Major Non-Cardiac Surgeries at High Risk for Transfusion: A Systematic Review and Meta-Analysis

Tranexamic acid (TXA) reduces transfusion requirements in cardiac surgery and total hip and knee arthroplasty, where it has become standard of care. Our objective is to determine the efficacy and safety of TXA in other surgeries associated with a high risk for red blood cell (RBC) transfusion. We identified randomized controlled trials in Medline, Embase, CENTRAL, and CAB abstracts from inception to June 2019. We included trials evaluating intraoperative IV TXA in adult patients undergoing a non-cardiac and non-hip and knee arthroplasty surgeries at high-risk for RBC transfusion, defined as a baseline transfusion rate ≥5% in comparator arm. We assessed risk of bias using the Cochrane Risk of Bias tool. We used GRADE methodology to assess certainty of evidence. From 8565 citations identified, we included 69 unique trials, enrolling 6157 patients. TXA reduces both the proportion of patients transfused RBCs (relative risk (RR) 0.59; 95% confidence interval (CI) 0.48 to 0.72; low certainty evidence) and the volume of RBC transfused (MD −0.51 RBC units; 95%CI −0.13 to −0.9 units; low certainty evidence) when compared to placebo or usual care. TXA was not associated with differences in deep vein thrombosis, pulmonary embolism, all-cause mortality, hospital length of stay, need for re-operation due to hemorrhage, myocardial infarction, stroke or seizure. In patients undergoing a broad range of non-cardiac and non-hip and knee arthroplasty surgeries at high risk for RBC transfusion, perioperative TXA reduced exposure to RBC transfusion. No differences in thrombotic outcomes were identified; however, summary effect estimates were limited by lack of systemic screening and short duration of follow-up.     

Plasma Transfusion in Patients With Cirrhosis in China: A Retrospective Multicenter Cohort Study

Patients with cirrhosis used to be associated with frequent use of blood components because of their complex disorder of hemostasis and bleeding complications. Recent findings have indicated that patients with cirrhosis have a state of “rebalanced” or even procoagulant hemostasis and have questioned the prophylactic use of plasma. To evaluate the current status of plasma use in patients with cirrhosis, we conducted a retrospective survey in 11 tertiary-care hospitals in China from September 1 to October 31, 2013. All patients admitted with cirrhosis during the study period were included in the study. The survey collected information including patients' diagnostic and demographic data, clinical course including bleeding complications and invasive procedures, laboratory results, and plasma transfusion data. Among 1595 patients with cirrhosis admitted to the 11 hospitals, 236 (14.8%) patients received 1 or more plasma transfusions during the study period. The number of plasma transfusions is defined as the number of transfusion orders. A total of 1037 plasma transfusions were administered to these patients, with a mean of 4.4 transfusions per transfused patient, ranging from 1 to 22 transfusions per transfused patient. Most plasma transfusions (760/1037; 73.3%) were given to patients without bleeding, for treatment of coagulopathy either without planned invasive procedures (70.4%) or before invasive procedures (2.9%). The median dose of plasma transfusion was 3.8 mL/kg. The rate of plasma transfusion of participating hospitals varied from 5.3% to 31.8%. It is encouraging to see that in one teaching hospital, 85.7% plasma transfusions were given to patients with bleeding indication, showing a promising sign in appropriate transfusion. Prophylaxis or empirical plasma transfusion is still a common problem in managing patients with liver cirrhosis. Wide variations are found in plasma transfusion practice among hospitals. Effective measures to control and reduce empirical correction of abnormal coagulation tests through transfusing plasma should be strengthened urgently.     

中国开胸肺叶切除术单病种患者围术期异体红细胞输注的纵向观察研究

目的 探究围术期限制性输血策略实施前后我国行开胸肺叶切除术单病种患者异体红细胞输注情况变化.方法 本研究是一项基于人群横断面数据形成的纵向研究,数据来源于医院质量监测系统数据库,研究对象为数据库中2013年1月1日至2018年8月31日我国三级医院行开胸肺叶切除术的所有患者.主要观察指标为围术期异体红细胞输注率,并构建...     

A Fresh Breath of Oxygen: Red Blood Cell Exchange Transfusion in Sickle Cell and COVID‐19

Red blood cell exchange transfusion may be beneficial and should be considered in the early management of patients with sickle cell disease and COVID‐19 to prevent the need for intubation and intensive care unit admission due to respiratory distress.     

Red Blood Cell Transfusion in Patients With Traumatic Brain Injury: A Systematic Review and Meta-Analysis

Our objectives were to evaluate the frequency of red blood cell (RBC) transfusion in patients with traumatic brain injury (TBI) as well as potential determinants and outcomes associated with RBC transfusion in this population. We conducted a systematic review of cohort studies and randomized trials of patients with TBI. We searched Medline, Embase, the Cochrane Library, and BIOSIS databases from their inception up to April 2015. We selected studies of adult patients with acute TBI reporting data on RBC transfusions. Cumulative incidences of transfusion were pooled using random-effect models with a DerSimonian approach. To evaluate the association between RBC transfusion and potential determinants or clinical outcomes, we pooled risk ratios or mean differences with random-effect models and the Mantel-Haenszel method. We identified 24 eligible studies (17 414 patients). After pooling data from 23 studies (7524 patients), approximately 36% (95% confidence interval [CI], 28-44; I² = 98%) of patients received RBC transfusion at some point during their hospital stay. Hemoglobin thresholds for transfusion were rarely available (reported in 9 studies) and varied from 6 to 10 g/dL. Glasgow Coma Scale scores at admission were lower in patients who were transfused than those who were not (3 cohort studies; 1371 patients; mean difference of 1.38 points [95% CI, 0.86-1.89]; I² = 12%). Mortality was not significantly different among transfused and nontransfused patients in univariate and multivariate meta-analyses. Hospital length of stay was longer among patients receiving RBC transfusion compared to those who did not (3 studies; n = 455; mean difference, 9.58 days [95% CI, 3.94-15.22]; I² = 74%). Results should be considered cautiously due to the high heterogeneity and high risk of confounding from the observational nature of included studies. Red blood cell transfusion is frequent in patients with TBI, and transfusion practices varied widely between studies. Current published data highlight the lack of clinical evidence guiding transfusion strategies in TBI.     

产科围产期输血的原因

  目的  分析产科围产期输血的相关因素, 以指导临床减少围产期出血。  方法  回顾性分析2013年1月至2014年12月于北京协和医院分娩并输血的80例产妇的临床资料, 分析产科输血的主要疾病类型, 计算其输血率及输血量, 筛选围产期输血的主要危险因素。  结果  输血产妇平均年龄(29.8±4.8)岁, 平均分娩孕周为(35.6±4.3)周。总用血量503 U, 其中红细胞悬液293 U, 血浆151 U, 血小板59 U。输血率超过20%的疾病依次为:HELLP综合征(61.1%)、凶险性前置胎盘(57.1%)、胎盘植入(57.1%)、妊娠期急性脂肪肝(57.1%)、胎盘早剥(50.0%)、血液病(41.2%)、宫缩乏力(40.7%)和重度子痫前期(24.2%)。平均输血量超过8 U的疾病依次为:急产(15.0 U)、凶险性前置胎盘(14.0 U)、胎盘植入(13.7 U)、胎盘早剥(13.2 U)和急性脂肪肝(9.6 U)。  结论  多种妊娠合并症和并发症可诱发严重的产后出血, 甚至发生常规手段难以控制的难治性产后出血。对高危产妇进行规范诊治、采取预防性措施、及时发现出血、提高止血技巧, 是减少产后出血量, 节约血制品, 并最终取得出血抢救成功的关键。     

Genetic Testing for Opioid Risk and Drug Metabolism: A Pain Clinic's Retrospective Cohort Study

PURPOSEThis investigation consisted of a survey of patients diagnosed with fibromyalgia or chronic fatigue who participated in the Fibromyalgia and Chronic Fatigue Clinic (FCFC) in a tertiary care center. This study assessed if patients preferred in-person or virtual educational sessions for their treatment program during the COVID pandemic. We hypothesized a relatively even split as to the preference of in-person or virtual sessions. The FCFC, operational since 1999, consists of in-depth educational sessions, led by RN staff. Patients receive 8 hours of education, divided into two 4-hour sessions. Educational topics include symptoms, pathophysiology, medication, and non-medication strategies. Since the inception of our clinic, these educational sessions have been provided via an in-person group setting. However, given the ramifications of the COVID-19 pandemic and the resultant changes in travel and infection control policies, we began offering the sessions online via Zoom. Currently we provide the option of traditional in-person or online sessions. Though the options are appreciated by our patients, we did not have any data to support the benefits or barriers that each of these options have.METHODSThe survey-based observational study utilized a Qualtrics survey that was emailed directly to patients following participation in either class format. After determining there were insufficient numbers from the in-person class participants, we printed out paper copies and asked patients who were willing, to complete those forms. This study was determined to be a quality assurance project by our Institutional Review Board.RESULTS90 patients completed the survey: 53 from the virtual sessions and 37 from in-person. Results highlighted patient preferences.CONCLUSIONAll patients reported they found the information valuable and that they were generally satisfied with their educational sessions. Virtual attendees identified some potential limitations, mainly not feeling as connected with peers or as engaged in the sessions.     

Red Blood Cell Antigen Genotyping for Sickle Cell Disease,Thalassemia, and Other Transfusion Complications

Since the discovery of the ABO blood group in the early 20th century, more than 300 blood group antigens have been categorized among 35 blood group systems. The molecular basis for most blood group antigens has been determined and demonstrates tremendous genetic diversity, particularly in the ABO and Rh systems. Several blood group genotyping assays have been developed, and 1 platform has been approved by the Food and Drug Administration as a “test of record,” such that no phenotype confirmation with antisera is required. DNA-based red blood cell (RBC) phenotyping can overcome certain limitations of hemagglutination assays and is beneficial in many transfusion settings. Genotyping can be used to determine RBC antigen phenotypes in patients recently transfused or with interfering allo- or autoantibodies, to resolve discrepant serologic typing, and/or when typing antisera are not readily available. Molecular RBC antigen typing can facilitate complex antibody evaluations and guide RBC selection for patients with sickle cell disease (SCD), thalassemia, and autoimmune hemolytic anemia. High-resolution RH genotyping can identify variant RHD and RHCE in patients with SCD, which have been associated with alloimmunization. In the future, broader access to cost-efficient, high-resolution RBC genotyping technology for both patient and donor populations may be transformative for the field of transfusion medicine.     

Effects of Positive Suggestions on the Need for Red Blood Cell Transfusion in Orthopedic Surgery

This study examined whether positive suggestions applied without a hypnotic induction in the perioperative period reduces the need for red blood cell transfusions in patients who underwent total hip or knee arthroplasties with spinal anesthesia. No hypnotic assessment was performed. Ninety-five patients were randomly assigned to the suggestion group (n = 45) and to the control group (n = 50). Patients in the suggestion group received verbal suggestions before and audiotaped suggestions during the surgery for reducing blood loss, anxiety, postoperative pain, and fast recovery. Our study showed that using positive suggestions in the perioperative period significantly decreases the necessity for transfusion.     

The Effect of Sex-Mismatched Red Blood Cell Transfusion on Endothelial Cell Activation in Critically Ill Patients

BackgroundObservational studies suggest that sex-mismatched transfusion is associated with increased mortality. Mechanisms driving mortality are not known but may include endothelial activation. The aim of this study is to investigate the effects of sex-mismatched red blood cell (RBC) transfusions on endothelial cell activation markers in critically ill patients.Study Design and MethodsIn patients admitted to the intensive care unit who received a single RBC unit, blood samples were drawn before (T₀), 1 h after (T₁), and 24 h after transfusion (T₂₄) for analysis of soluble syndecan-1, soluble intercellular adhesion molecule-1, soluble thrombomodulin (sTM), von Willebrand factor antigen, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNFα). Changes in the levels of these factors were compared between sex-matched and sex-mismatched groups.ResultsOf 69 included patients, 32 patients were in the sex-matched and 37 patients were in the sex-mismatched group. Compared to baseline, sex-matched transfusion was associated with significant reduction in sTM level (p value = 0.03). Between-group comparison showed that levels of syndecan-1 and sTM were significantly higher in the sex-mismatched group compared to the sex-matched group at T₂₄ (p value = 0.04 and 0.01, respectively). Also, TNFα and IL-6 levels showed a statistically marginal significant increase compared to baseline in the sex-mismatched group at T₂₄ (p value = 0.06 and 0.05, respectively), but not in the sex-matched group.DiscussionTransfusion of a single sex-mismatched RBC unit was associated with higher syndecan-1 and sTM levels compared to transfusion of sex-matched RBC unit. These findings may suggest that sex-mismatched RBC transfusion is associated with endothelial activation.     

临床大剂量输注两种不同红细胞悬液的疗效评估

目的评估红细胞悬液经滤除白细胞后降低输血副作用的效果。方法选取1998年1月~2001年10月间148份大剂量输血的手术病历,记录红细胞悬液或去白细胞红细胞悬液输注前、输注1d后的指标,包括白细胞计数(WBC)、谷草转氨酶(GOT)、谷丙转氨酶(ALT)、总胆红素(TB)、直接胆红素(DB)、肌酐(Cr)、血糖(GLU)、血K和Ca离子浓度、pH值,并比较非溶血性发热反应(FNHTR)的发生率,分析两种成分输血对患者机体的影响。结果在红细胞悬液输注组,术后GOT、ALT、Cr、WBC、GLU、IB、TB的增高与红细胞悬液输注有关(P<0.05),血钾、钙离子浓度和pH的变化不显著(P>0.05);在白细胞去除组,手术前后各项指标的变化均不显著(P>0.05)。输注红细胞悬液组FNTHR发生率为75.6%。结论去白细胞红细胞悬液在大剂量输血中的应用,可有效防止FNTHR的发生,降低因红细胞悬液中白细胞和血小板-白细胞复合物(PLA)对患者机体造成的损伤。     

Screening Adolescents at Risk for Vitamin D Deficiency: A Retrospective Study

Clinical practice guidelines differ on screening recommendations and definitions for adequate vitamin D levels. A chart review of 32 overweight/obese adolescents showed that 91% had low vitamin D levels based on the Endocrine Society definition of sufficient levels (≥ 30 ng/mL), whereas only 56% were low based on the American Academy of Pediatrics definition of sufficient levels (>20 ng/mL). Nurse practitioners should routinely inquire about exercise, healthy diet, and outdoor activities to identify those at risk for low vitamin D. A consensus in recommendations for vitamin D screening and sufficient serum levels would be beneficial for nurse practitioners for early recognition and consistency in care.