Transfusion thresholds and other strategies for guiding allogeneic red blood cell transfusion

Red blood cell transfusion associated with increased morbidity and mortality in patients undergoing elective open abdominal aortic aneurysm repair

BACKGROUND

Red blood cell (RBC) transfusions are associated with increased mortality and morbidity. The aim of this analysis was to examine the association between RBC transfusions and long-term survival for patients undergoing elective open infrarenal abdominal aortic aneurysm (AAA) repair with up to 15 years of follow-up.

METHODS

Prospective cohort study using data from The Danish Vascular Registry from 2000-2015. Primary endpoint was all-cause mortality. Secondary endpoints were in-hospital complications. Transfused patients were divided into subgroups based on received RBC transfusions (1, 2-3, 4-5 or > 5). Using Cox regression multi-adjusted analysis, non-transfused patients were compared to transfused patients (1, 2-3, 4-5, >5 transfusions) for both primary and secondary endpoints.

RESULTS

There were 3 876 patients included with a mean survival of 9.1 years. There were 801 patients who did not receive transfusions. Overall 30-day mortality was 3.1% (121 patients) and 3.6% (112) for all transfused patients. For the five subgroups 30-day mortality was: No transfusions 1.1% (9 patients), 1 RBC 1.2% (4 patients), 2-3 RBC 2.2% (26 patients), 4-5 RBC 1.9% (14 patients) and > 5 RBC 7.9% (68 patients). After receiving RBCs, the hazard ratio for death was 1.54 (95% CI 1.27-1.85) compared to non-transfused patients. There was a significant increase in mortality when receiving 2-3 RBC: HR 1.32 (95% CI 1.07-1.62), 4-5 RBC: 1.64 (1.32-2.03) and >5 RBC: 1.96 (1.27-1.85) in a multi-adjusted model.

CONCLUSION

There is a dose-dependent association between RBC transfusions received during elective AAA repair and an increase in short- and long-term mortality. Approximately 25% of included patients had preoperative anemia. These findings should raise awareness regarding potentially unnecessary and harmful RBC transfusions.

Management of the patient presenting with anaemia in the preoperative setting

Preoperative anaemia is common, seen in a third of patients before major surgery. Both preoperative anaemia and blood transfusion are associated with increased patient risk and adverse outcome. Patient Blood Management (PBM) is the multidisciplinary, multimodal approach to optimising the care of patients who may require blood transfusion. Guidelines exist with many recommendations throughout the perioperative pathway. However, the efficacy of individual recommendations as an intervention in terms of clinical outcome can be confusing. In the UK the first national audit of PBM in surgery was carried out in 2015. This reviewed the use and impact of PBM recommendations in hospitals throughout the UK where major surgery was undertaken. The current evidence base for these PBM recommendations was reviewed and the patient outcome in terms of blood transfusion use and length of hospital stay assessed in those where PBM interventions were followed. For the patient who presents with preoperative anaemia, 'quick wins' were identified that reduced blood transfusion use and reduced length of stay in hospital; preoperative discontinuation of anticoagulation or antiplatelet therapy, and intraoperative use of tranexamic acid and cell salvage.

Should Transfusion Trigger Thresholds Differ for Critical Care Versus Perioperative Patients? A Meta-Analysis of Randomized Trials

Supplemental Digital Content is available in the text.

Objective:

To address the significant uncertainty as to whether transfusion thresholds for critical care versus surgical patients should differ.

Design:

Meta-analysis of randomized controlled trials.

Setting:

Medline, EMBASE, and Cochrane Library searches were performed up to 15 June 2016.

Patients:

Trials had to enroll adult surgical or critically ill patients for inclusion.

Interventions:

Studies had to compare a liberal versus restrictive threshold for the transfusion of allogeneic packed RBCs.

Measurements and Main Results:

The primary outcome was 30-day all-cause mortality, sub-grouped by surgical and critical care patients. Secondary outcomes included myocardial infarction, stroke, renal failure, allogeneic blood exposure, and length of stay. Odds ratios and weighted mean differences were calculated using random effects meta-analysis. To assess whether subgroups were significantly different, tests for subgroup interaction were used. Subgroup analysis by trials enrolling critically ill versus surgical patients was performed. Twenty-seven randomized controlled trials (10,797 patients) were included. In critical care patients, restrictive transfusion resulted in significantly reduced 30-day mortality compared with liberal transfusion (odds ratio, 0.82; 95% CI, 0.70–0.97). In surgical patients, a restrictive transfusion strategy led to the opposite direction of effect for mortality (odds ratio, 1.31; 95% CI, 0.94–1.82). The subgroup interaction test was significant (p = 0.04), suggesting that the effect of restrictive transfusion on mortality is statistically different for critical care (decreased risk) versus surgical patients (potentially increased risk or no difference). Regarding secondary outcomes, for critically ill patients, a restrictive strategy resulted in reduced risk of stroke/transient ischemic attack, packed RBC exposure, transfusion reactions, and hospital length of stay. In surgical patients, restrictive transfusion resulted in reduced packed RBC exposure.

Conclusions:

The safety of restrictive transfusion strategies likely differs for critically ill patients versus perioperative patients. Further trials investigating transfusion strategies in the perioperative setting are necessary.

An online educational module on transfusion safety and appropriateness for resident physicians: a controlled before-after quality-improvement study

BACKGROUND

Several professional societies have made value-based statements in support of restrictive transfusion strategies. The aim of this study was to determine whether completion of an accredited online training program in transfusion safety could improve transfusion knowledge among medical residents and increase transfusion appropriateness.

METHODS

We performed a controlled before-after evaluation of a mandatory accredited self-directed training program (Bloody Easy Lite for Physicians) that provides education about transfusion medicine on a 47-bed medical clinical teaching unit at a university-affiliated hospital centre in Montréal. The program consists of 2 modules and takes about 30 minutes to complete. We used the 45-bed medical teaching unit at another Montréal hospital as a contemporary control. We compared resident physicians' pre- and posttest scores and evaluated the impact on transfusion appropriateness by comparing the proportion occurring below a hemoglobin concentration of 80 g/L before (April 2013-June 2015) and after (July 2015-January 2016) the intervention.

RESULTS

Of the 55 residents on the intervention unit, 53 (96%) completed the training. The median pretest score was 50% (inter-quartile range [IQR] 40%-60%). The median posttest score was 90% (IQR 80%-90%) for module 1 and 80% (IQR 80%-90%) for module 2 (p < 0.001 for both pre-post comparisons). The proportion of transfusions below 80 g/L increased from 80.1% to 86.9% (p = 0.04) on the intervention unit and remained relatively unchanged on the control unit (75.6% v. 71.1%, p = 0.4). Although there was no statistically significant difference between the units in the proportion of transfusions below 80 g/L before the intervention (p = 0.07), a significant difference was observed after the intervention (p = 0.002).

INTERPRETATION

Mandatory training in transfusion safety via an online program resulted in improved transfusion knowledge among residents and an increase in the proportion of transfusions occurring at a hemoglobin concentration below 80 g/L. This low-cost educational initiative may improve transfusion appropriateness.

Patient blood management: A solution for South Africa

For more than 70 years the default therapy for anaemia and blood loss was mostly transfusion. Accumulating evidence demonstrates a significant dose-dependent relationship between transfusion and adverse outcomes. This and other transfusion-related challenges led the way to a new paradigm. Patient blood management (PBM) is the application of evidence-based practices to optimise patient outcomes by managing and preserving the patient's own blood. 'Real-world' studies have shown that PBM improves patient outcomes and saves money. The prevalence of anaemia in adult South Africans is 31% in females and 17% in males. Improving the management of anaemia will firstly improve public health, secondly relieve the pressure on the blood supply, and thirdly improve the productivity of the nation's workforce. While high-income countries are increasingly implementing PBM, many middle- and low-income countries are still trying to upscale their transfusion services. The implementation of PBM will improve South Africa's health status while saving costs.

Safety of a Restrictive versus Liberal Approach to Red Blood Cell Transfusion on the Outcome of AKI in Patients Undergoing Cardiac Surgery: A Randomized Clinical Trial

BACKGROUND

Safely reducing red blood cell transfusions can prevent transfusion-related adverse effects, conserve the blood supply, and reduce health care costs. Both anemia and red blood cell transfusion are independently associated with AKI, but observational data are insufficient to determine whether a restrictive approach to transfusion can be used without increasing AKI risk.

METHODS

In a prespecified kidney substudy of a randomized noninferiority trial, we compared a restrictive threshold for red blood cell transfusion (transfuse if hemoglobin<7.5 g/dl, intraoperatively and postoperatively) with a liberal threshold (transfuse if hemoglobin<9.5 g/dl in the operating room or intensive care unit, or if hemoglobin<8.5 g/dl on the nonintensive care ward). We studied 4531 patients undergoing cardiac surgery with cardiopulmonary bypass who had a moderate-to-high risk of perioperative death. The substudy's primary outcome was AKI, defined as a postoperative increase in serum creatinine of ≥0.3 mg/dl within 48 hours of surgery, or ≥50% within 7 days of surgery.

RESULTS

Patients in the restrictive-threshold group received significantly fewer transfusions than patients in the liberal-threshold group (1.8 versus 2.9 on average, or 38% fewer transfusions in the restricted-threshold group compared with the liberal-threshold group; P<0.001). AKI occurred in 27.7% of patients in the restrictive-threshold group (624 of 2251) and in 27.9% of patients in the liberal-threshold group (636 of 2280). Similarly, among patients with preoperative CKD, AKI occurred in 33.6% of patients in the restrictive-threshold group (258 of 767) and in 32.5% of patients in the liberal-threshold group (252 of 775).

CONCLUSIONS

Among patients undergoing cardiac surgery, a restrictive transfusion approach resulted in fewer red blood cell transfusions without increasing the risk of AKI.

Sociodemographic and behavioral characteristics associated with blood donation in the United States: a population-based study

BACKGROUND

Contemporary population-based data on characteristics associated with blood donation in the United States (U.S.) are limited.

STUDY DESIGN AND METHODS

A cross-sectional analysis was performed among 28,739 persons aged 18 years and older who participated in the 2016 National Health Interview Survey, a household survey of the noninstitutionalized U.S. civilian population. Analyses were weighted and accounted for the complex survey design. Adjusted prevalence ratios (aPR) were estimated by multivariable log-binomial regression.

RESULTS

The percentage of individuals reporting a past-year history of blood donation was 5.7% (95% confidence interval [CI], 5.3%-6.1%) and was highest in the youngest age group (18-24 years, 8.4%). A past-year history of blood donation was more common in males compared to females (6.3% vs. 5.1%; aPR, 1.12 [95% CI, 0.99-1.27]) and those born in the U.S. compared to individuals born outside the U.S. (6.4% vs. 2.4%; aPR, 1.92 [95% CI, 1.49-2.47]). The percentage of individuals with a past-year history of blood donation was significantly lower in blacks (3.9%; aPR, 0.60 [95% CI, 0.47-0.75]) and Hispanics (3.0%; aPR, 0.63 [95% CI, 0.48-0.83]) in comparison to whites (6.9%). Being a college graduate, being employed, being physically active, and never being a cigarette smoker were factors positively associated with blood donation. The percentage of individuals with a past-year history of blood donation varied by geographic census region, with prevalence being higher in the Midwest (7.3%) and South (6.0%) compared to the Northeast (4.7%) and West (4.4%).

CONCLUSION

Continued differences in the blood donor population with reference to the U.S. population underscore the need to understand barriers or deterrents to blood donation. Evidence-based donor recruitment and related policies remain imperative to ensure that there is a sustainable blood supply.

Red blood cell transfusions for emergency department patients with gastrointestinal bleeding within an integrated health system

STUDY OBJECTIVE

To assess trends over time in red blood cell (RBC) transfusion practice among emergency department (ED) patients with gastrointestinal (GI) bleeding within an integrated healthcare system, inclusive of 21 EDs.

METHODS

Retrospective cohort of ED patients diagnosed with GI bleeding between July 1st, 2012 and September 30th, 2016. The primary outcome was receipt of an RBC transfusion in the ED. Secondary outcomes included 90-day rates of RBC transfusion, repeat ED visits, rehospitalization, and all-cause mortality. Logistic regression was used to obtain confounder-adjusted outcome rates.

RESULTS

A total of 24,868 unique patient encounters were used for the primary analysis. The median hemoglobin level in the ED prior to RBC transfusion decreased from 7.5 g/dl to 6.9 g/dl in the first versus last twelve months of the study period (p < 0.0001). A small trend was observed in the overall adjusted rate of ED RBC transfusion (absolute quarterly change of -0.1%, R2 = 0.18, p = 0.0001) largely attributable to the subgroup of patients with hemoglobin nadirs between 7.0 and 9.9 g/dl (absolute quarterly change of -0.4%, R2 = 0.38, p < 0.0001). Rates of RBC transfusions through 90 days likewise decreased (absolute quarterly change of -0.4%, R2 = 0.85, p < 0.0001) with stable to decreased corresponding rates of repeat ED visits, rehospitalizations and mortality.

CONCLUSION

Rates of ED RBC transfusion decreased over time among patients with GI bleeding, particularly in those with hemoglobin nadirs between 7.0 and 9.9 g/dl. These findings suggest that ED providers are willing to adopt evidence-based restrictive RBC transfusion recommendations for patients with GI bleeding.

The Romanian Society of Internal Medicine's Choosing Wisely Campaign

Quality of care in medicine is not necessarily proportional to quantity of care and excess is often useless or even more, potentially detrimental to our patients. Adhering to the European Federation of Internal Medicine's initiative, the Romanian Society of Internal Medicine (SRMI) launched the Choosing Wisely in Internal Medicine Campaign, aiming to cut down diagnostic procedures or therapeutics overused in our country. A Working Group was formed and from 200 published recommendations from previous international campaigns, 36 were voted as most important. These were submitted for voting to the members of the SRMI and posted on a social media platform. After the two voting rounds, the top six recommendations were established. These were: 1. Stop medicines when no further benefit is achieved or the potential harms outweigh the potential benefits for the individual patient. 2. Don't use antibiotics in patients with recent C. difficile without convincing evidence of need. 3. Don't regularly prescribe bed rest and inactivity following injury and/or illness unless there is scientific evidence that harm will result from activity. Promote early mobilization. 4. Don't initiate an antibiotic without an identified indication and a predetermined length of treatment or review date. 5. Don't prescribe opioids for treatment of chronic or acute pain for sensitive jobs such as operating motor vehicles, forklifts, cranes or other heavy equipment. 6. Transfuse red cells for anemia only if the hemoglobin concentration is less than 7 g/dL or if the patient is hemodynamically unstable or has significant cardiovascular or respiratory comorbidity. Don't transfuse more units of blood than absolutely necessary.

Intra-operative red blood cell transfusion and mortality after cardiac surgery

Background

Anemia in cardiac surgery patients has been associated with poor outcomes. Transfusion of red blood cells during surgery is common practice for perioperative anemia, but may come with risks. Little is known about the association between intra-operative transfusion and mortality in patients undergoing cardiac surgery.

Methods

Single centre historical cohort study in 2933 adult patients undergoing coronary surgery with or without aortic valve replacement from June 2011 until September 2014. To estimate the odds ratio for mortality in patients receiving intra-operative transfusion, a propensity score based logistic regression analysis was performed.

Results

Intra-operative transfusion was associated with a more than three-fold increased risk of 30-day mortality. Patients in the highest quartile of probability of transfusion were older (age 75 vs 66; P <  0.001), had a higher EuroSCORE (6 vs 3; P <  0.001), had lower preoperative hemoglobin levels (7.6 vs 8.9 mmol/l; P < 0.001), had combined surgery more often (CABG + AVR in 33.4% of cases vs 6.6% (P < 0.001) and a longer duration of surgery (224 vs 188 min; P < 0.001). The association between intra-operative transfusion and mortality persisted after adjustment for these risk factors (adjusted OR 2.6; P = 0.007).

Conclusions

Intra-operative transfusion of red blood cells was found to be associated with increased mortality in adults undergoing coronary surgery. Preoperative patient optimization may improve perioperative outcomes by reducing the likelihood of requiring transfusion and thus its associated risk.

Patient Blood Management: a revolutionary approach to transfusion medicine

Patient Blood Management (PBM) is a multimodal, multidisciplinary approach adopted to limit the use and the need for allogeneic blood transfusion in all at-risk patients with the aim of improving their clinical outcomes. Although PBM usually refers to surgical patients, its clinical use has gradually evolved over the last few years and it now also refers to medical conditions. This review will critically analyse the current knowledge on the use of PBM programmes in surgical and non-surgical patients.

Red blood cell transfusion in critically ill patients with traumatic brain injury: an international survey of physicians' attitudes

INTRODUCTION

Restrictive transfusion strategies have been advocated in critically ill patients. Nevertheless, considerable uncertainty exists regarding optimal transfusion thresholds in traumatic brain injury (TBI) patients because the injured brain is susceptible to hypoxemic damage. We aimed to identify the determinants of red blood cell (RBC) transfusion and the perceived optimal transfusion thresholds in adult patients with moderate-to-severe TBI.

METHODS

We conducted an electronic, self-administered survey targeting critical care specialists and neurosurgeons from Canada, Australia, and the United Kingdom caring for TBI patients. The questionnaire was initially developed by a panel of experts using a structured process (domains/items generation and reduction). The questionnaire was validated for clinical sensibility, reliability, and content.

RESULTS

The response rate was 28.7% (218/760). When presented with the hypothetical scenario of a young adult TBI patient, a wide range of transfusion practices was observed, with 47 (95% confidence interval [CI], 41 to 54)% favouring RBC transfusion at a hemoglobin level of ≤ 70 g·L^-1 in the acute phase of care, while 73 (95% CI, 67 to 79)% would use this trigger in the plateau phase of care. Multiple trauma, neuro-monitoring data, hemorrhagic shock, and planned surgery were the main factors that influenced the need for transfusion. The lack of clinical evidence and guidelines was responsible for uncertainty regarding RBC transfusion strategies in this patient population.

CONCLUSION

In our survey about critically ill TBI patients, transfusion practice was found to be mainly influenced by the acuity of care, patient characteristics, and neuro-monitoring. Clinical equipoise regarding optimal transfusion strategy is believed to be mainly attributed to the lack of clear clinical evidence and guidelines. Appropriate randomized-controlled trials are required to determine the optimal transfusion strategies in TBI patients.

A retrospective observational analysis of red blood cell transfusion practices in stable, non-bleeding adult patients admitted to nine medical-surgical intensive care units

Background

Red blood cell (RBC) transfusions are common procedures performed in the intensive care unit (ICU). However, conservative transfusion approaches have been recommended to avoid RBC transfusions that are not clinically necessary and to achieve optimal patient outcomes. The objective of this study was to examine the utilization and costs of RBC transfusions in medical-surgical ICUs and to compare this information against clinical guideline recommendations for best practice.

Methods

Retrospective observational analysis of RBC transfusions in stable, non-bleeding adult patients was examined in a geographically-defined, population-based cohort of nine integrated ICUs between April 1, 2014 and December 31, 2016. RBC transfusions associated with a pre-transfusion hemoglobin value of 70 g/L or more were examined through linear and logistic regression. The total costs of RBC transfusions, based on the RBC unit cost, were estimated.

Results

A total of 4632 RBC transfusions (2287 ICU admissions) were included. Pre-transfusion hemoglobin values were identified for 4487 transfusions. On average, 61% occurred at or above a hemoglobin value of 70 g/L (mean 73.4 ± 9.2 g/L). Factors associated with such transfusions included being male, age over 75, Sequential Organ Failure Assessment (SOFA) score greater or equal to 10, transfer from operating room, gastrointestinal bleeding, and trauma. A pre-transfusion hemoglobin value at or above 70 g/L was associated with increased odds of ICU mortality; there was no impact on overall hospital mortality. The total estimated cost of RBC transfusions was $2.99M Canadian dollars (CAD), with $1.82M CAD attributed to those with a hemoglobin value at or above 70 g/L.

Conclusions

Over half of the examined RBC transfusions may not have aligned with recommended best practice; this suggests significant opportunity for improvement. The present findings are an essential step towards optimizing RBC transfusions in the ICU.

Electronic supplementary material

The online version of this article (10.1186/s40560-019-0375-3) contains supplementary material, which is available to authorized users.

Patterns of care in Jehovah's Witnesses patients with solid tumours and lymphoma

BACKGROUND

Supportive care of Jehovah's Witnesses (JWs) diagnosed with cancer can be challenging, as they do not accept red blood cell (RBC) transfusions.

AIM

The study was designed to determine treatment preferences and pattern of care offered to JWs diagnosed with cancer and its impact on cancer management.

METHODS AND RESULTS

A retrospective cohort study of JWs with solid malignancies or lymphoma in our institution between 2005 and 2015 was conducted. Survival statistics were estimated using Kaplan Meier survival curves and Cox proportional regression model. A total of 63 JWs were identified with a median age of 70 years. At diagnosis, 34% (n = 22) had anaemia. All 63 declined RBC transfusion, including 19 patients who later developed transfusion threshold during anti-cancer treatment. Forty-three percent (n = 27) JWs had advanced (stage 4) disease, and 76% (n = 48) had Eastern Cooperative Oncology Group of 0 to 1. JWs were willing to accept surgery and radiation rather than chemotherapy. Treatment was deemed to be suboptimal in 22% (n = 14) JWs due to early treatment discontinuation, administration of non-standard chemotherapy regimen, or dose reduction due to anaemia and denial of blood transfusion. Twenty-seven percent (n = 17) received hematopoietic growth factors (erythropoiesis-stimulating agents and pegfilgrastim). There was no mortality directly attributed to anaemia or refusal of blood transfusion in the entire cohort.

CONCLUSION

Jehovah's Witnesses declined RBC transfusion at diagnosis and during cancer therapy even if medically indicated. Management pathways need to be prospectively defined for this group of patients.

Choosing Wisely: Decreasing the incidence of perioperative blood transfusions in gynecologic oncology

OBJECTIVE

To evaluate the efficacy and economic impact of a transfusion reduction initiative for patients undergoing gynecologic surgery.

METHODS

We conducted a prospective healthcare improvement study to align transfusion practices with the American Society of Hematology's Choosing Wisely® campaign. Baseline transfusion rates were determined retrospectively for all major gynecologic surgical cases from 3/1/14 to 6/30/14. Data for the post-intervention period from 5/15/15 to 5/16/16 were captured prospectively. The primary outcome was transfusion within 72 h of surgery. Secondary outcomes included perioperative morbidity, mortality, number of units ordered per transfusion episode and cost.

RESULTS

We identified 1281 surgical cases, 334 in the baseline and 947 in the post-implementation cohort. The baseline cohort was noted to have a higher median estimated blood loss (100 v. 75 mL, P < 0.01). Otherwise, there were no differences in clinical or perioperative characteristics between the two cohorts. The perioperative transfusion rate decreased from 24% to 11% (adjusted OR 0.27, 95% CI 0.16 to 0.45; P < 0.001). The perioperative laparotomy transfusion rate decreased from 48% to 23% (adjusted OR 0.21, 95% CI 0.12, 0.37; P < 0.001). The number of occurrences in which more than one unit of blood was ordered at a time decreased from 65% to 23%, P < 0.001. The incidence of surgical site infections declined in the post-intervention group, otherwise there were no differences in 30-day mortality, cardiac, venous thromboembolism or readmission rates between the groups. The projected cost savings was $161,112 over the 12-month intervention period.

CONCLUSIONS

Implementation of an educational based transfusion reduction program was associated with substantial reductions in perioperative transfusions and cost without significant changes in morbidity or mortality.

Long-Term Outcomes Among Patients Discharged From the Hospital With Moderate Anemia: A Retrospective Cohort Study

BACKGROUND

Randomized clinical trial findings support decreased red blood cell (RBC) transfusion and short-term tolerance of in-hospital anemia. However, long-term outcomes related to changes in transfusion practice have not been described.

OBJECTIVE

To describe the prevalence of anemia at and after hospital discharge and associated morbidity and mortality events.

DESIGN

Retrospective cohort study.

SETTING

Integrated health care delivery system with 21 hospitals serving 4 million members.

PARTICIPANTS

445 371 surviving adults who had 801 261 hospitalizations between January 2010 and December 2014.

MEASUREMENTS

Hemoglobin levels and RBC transfusion, rehospitalization, and mortality events within 6 months of hospital discharge. Generalized estimating equations were used to examine trends over time, accounting for correlated observations and patient-level covariates.

RESULTS

From 2010 to 2014, the prevalence of moderate anemia (hemoglobin levels between 7 and 10 g/dL) at hospital discharge increased from 20% to 25% (P < 0.001) and RBC transfusion declined by 28% (39.8 to 28.5 RBC units per 1000 patients; P < 0.001). The proportion of patients whose moderate anemia had resolved within 6 months of hospital discharge decreased from 42% to 34% (P < 0.001), and RBC transfusion and rehospitalization within 6 months of hospital discharge decreased from 19% to 17% and 37% to 33%, respectively (P < 0.001 for both). During this period, the adjusted 6-month mortality rate decreased from 16.1% to 15.6% (P = 0.004) in patients with moderate anemia, in parallel with that of all others.

LIMITATION

Possible unmeasured confounding.

CONCLUSION

Anemia after hospitalization increased in parallel with decreased RBC transfusion. This increase was not accompanied by a rise in subsequent RBC use, rehospitalization, or mortality within 6 months of hospital discharge. Longitudinal analyses support the safety of practice recommendations to limit RBC transfusion and tolerate anemia during and after hospitalization.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute.

Implementation of a restrictive blood transfusion protocol in a gynecologic oncology service

Objectives

The purpose of this study was to evaluate the impact of a restrictive blood transfusion protocol in a postoperative gynecologic oncology population. The primary objective was the rate of blood transfusions after surgery before and after implementation of a restrictive transfusion protocol (from July 1^st 2011 to December 30^th 2016). Secondary outcomes were patient morbidity and included rates of surgical site infection, pneumonia, sepsis, unplanned intubation, prolonged ventilator use, renal insufficiency, acute renal failure, urinary tract infection, cerebral vascular accident, cardiac complications, venous thromboembolism, and death within 30 days of surgery, readmissions and length of stay.

Methods

A restrictive blood transfusion protocol was implemented by the gynecologic oncology service at a National Comprehensive Cancer Network designated Comprehensive Cancer Center on January 1^st, 2014. The restrictive protocol required that no patient receive a blood transfusion for hemoglobin greater than 7.0 g/dL (or hematocrit greater than 21.0%) and that all red blood cells were administered in one unit increments followed by re-evaluation of blood parameters. Exceptions to this protocol were postoperative symptomatic anemia, intraoperative or day of surgery transfusion, active bleeding, postoperative severe sepsis, postoperative active coronary ischemia, and postoperative transfusion after 1.5 liter or greater blood loss.

Results

1482 patients were identified for this study (755 in the pre-protocol group and 727 in the post-protocol group). Patients treated under the restrictive protocol had decreased rates of red blood cell transfusion (11.0% vs 5.9% p<0.001), superficial surgical site infection (7.7% vs 4.1% p=0.005), deep surgical site infection (2.3% vs 0.7% p=0.02), and median length of stay (3.0 days vs 2.0 days p<0.001).

Conclusions

A restrictive blood transfusion protocol is associated with reductions in the rates of blood transfusions and postoperative morbidity with a 46.8% reduction in superficial surgical site infection and a 69.6% decrease in deep surgical site infection in the gynecologic oncology patient population.

Transfusion of red blood cells stored for shorter versus longer duration for all conditions

BACKGROUND

Red blood cell (RBC) transfusion is a common treatment for anaemia in many conditions. The safety and efficacy of transfusing RBC units that have been stored for different durations before a transfusion is a current concern. The duration of storage for a RBC unit can be up to 42 days. If evidence from randomised controlled trials (RCT) were to indicate that clinical outcomes are affected by storage duration, the implications for inventory management and clinical practice would be significant.

OBJECTIVES

To assess the effects of using red blood cells (RBCs) stored for a shorter versus a longer duration, or versus RBCs stored for standard practice duration, in people requiring a RBC transfusion.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, PubMed (for epublications), LILACS, Transfusion Evidence Library, Web of Science CPCI-S and four international clinical trial registries on 20 November 2017.

SELECTION CRITERIA

We included RCTs that compared transfusion of RBCs of shorter versus longer storage duration, or versus standard practice storage duration.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods.

MAIN RESULTS

We included 22 trials (42,835 participants) in this review.The GRADE quality of evidence ranged from very low to moderate for our primary outcome of in-hospital and short-term mortality reported at different time points.Transfusion of RBCs of shorter versus longer storage duration Eleven trials (2249 participants) compared transfusion of RBCs of shorter versus longer storage duration. Two trials enrolled low birth weight neonates, two enrolled children with severe anaemia secondary to malaria or sickle cell disease, and eight enrolled adults across a range of clinical settings (intensive care, cardiac surgery, major elective surgery, hospitalised in-patients, haematology outpatients). We judged only two trials to be at low risk of bias across all domains; most trials had an unclear risk for multiple domains.Transfusion of RBCs of shorter versus longer storage duration probably leads to little or no difference in mortality at seven-day follow-up (risk ratio (RR) 1.42, 95% confidence interval (CI) 0.66 to 3.06; 1 trial, 3098 participants; moderate quality evidence) or 30-day follow-up (RR 0.85, 95%CI 0.50 to 1.45; 2 trials, 1121 participants; moderate quality evidence) in adults undergoing major elective cardiac or non-cardiac surgery.For neonates, no studies reported on the primary outcome of in-hospital or short-term mortality. At 40 weeks gestational age, the effect of RBCs of shorter versus longer storage duration on the risk of death was uncertain, as the quality of evidence is very low (RR 0.90, 95% CI 0.41 to 1.85; 1 trial, 52 participants).The effect of RBCs of shorter versus longer storage duration on the risk of death in children with severe anaemia was also uncertain within 24 hours of transfusion (RR 1.50, 95% CI 0.43 to 5.25; 2 trials, 364 participants; very low quality evidence), or at 30-day follow-up (RR 1.40, 95% CI 0.45 to 4.31; 1 trial, 290 participants; low quality evidence).Only one trial, in children with severe anaemia (290 participants), reported adverse transfusion reactions. Only one child in each arm experienced an adverse reaction within 24 hours of transfusion.Transfusion of RBCs of shorter versus standard practice storage duration Eleven trials (40,588 participants) compared transfusion of RBCs of shorter versus standard practice storage duration. Three trials enrolled critically ill term neonates; two of these enrolled very low birth weight neonates. There were no trials in children. Eight trials enrolled critically ill and non-critically ill adults, with most being hospitalised. We judged four trials to be at low risk of bias across all domains with the others having an unclear risk of bias across multiple domains.Transfusion of RBCs of shorter versus standard practice storage duration probably leads to little or no difference in adult in-hospital mortality (RR 1.05, 95% CI 0.97 to 1.14; 4 trials, 25,704 participants; moderate quality evidence), ICU mortality (RR 1.06, 95% CI 0.98 to 1.15; 3 trials, 13,066 participants; moderate quality evidence), or 30-day mortality (RR 1.04, 95% CI 0.96 to 1.13; 4 trials, 7510 participants;moderate quality evidence).Two of the three trials that enrolled neonates reported that there were no adverse transfusion reactions. One trial reported an isolated case of cytomegalovirus infection in participants assigned to the standard practice storage duration group. Two trials in critically ill adults reported data on transfusion reactions: one observed no difference in acute transfusion reactions between arms (RR 0.67, 95% CI 0.19 to 2.36, 2413 participants), but the other observed more febrile nonhaemolytic reactions in the shorter storage duration arm (RR 1.48, 95% CI 1.13 to 1.95, 4919 participants).Trial sequential analysis showed that we may now have sufficient evidence to reject a 5% relative risk increase or decrease of death within 30 days when transfusing RBCs of shorter versus longer storage duration across all patient groups.

AUTHORS' CONCLUSIONS

The effect of storage duration on clinically important outcomes has now been investigated in large, high quality RCTs, predominantly in adults. There appears to be no evidence of an effect on mortality that is related to length of storage of transfused RBCs. However, the quality of evidence in neonates and children is low. The current practice in blood banks of using the oldest available RBCs can be continued safely. Additional RCTs are not required, but research using alternative study designs, should focus on particular subgroups (e.g. those requiring multiple RBC units) and on factors affecting RBC quality.

TACO and TRALI: biology, risk factors, and prevention strategies

Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are the leading causes of transfusion-related morbidity and mortality. These adverse events are characterized by acute pulmonary edema within 6 hours of a blood transfusion and have historically been difficult to study due to underrecognition and nonspecific diagnostic criteria. However, in the past decade, in vivo models and clinical studies utilizing active surveillance have advanced our understanding of their epidemiology and pathogenesis. With the adoption of mitigation strategies and patient blood management, the incidence of TRALI and TACO has decreased. Continued research to prevent and treat these severe cardiopulmonary events is focused on both the blood component and the transfusion recipient.

An international consensus statement on the management of postoperative anaemia after major surgical procedures

Despite numerous guidelines on the management of anaemia in surgical patients, there is no pragmatic guidance for the diagnosis and management of anaemia and iron deficiency in the postoperative period. A number of experienced researchers and clinicians took part in a two-day expert workshop and developed the following consensus statement. After presentation of our own research data and local policies and procedures, appropriate relevant literature was reviewed and discussed. We developed a series of best-practice and evidence-based statements to advise on patient care with respect to anaemia and iron deficiency in the postoperative period. These statements include: a diagnostic approach to iron deficiency and anaemia in surgical patients; identification of patients appropriate for treatment; and advice on practical management and follow-up that is easy to implement. Available data allow the fulfilment of the requirements of Pillar 1 of Patient Blood Management. We urge national and international research funding bodies to take note of these recommendations, particularly in terms of funding large-scale prospective, randomised clinical trials that can most effectively address the important clinical questions and this clearly unmet medical need.

Preoperative anemia and perioperative blood transfusion in head and neck squamous cell carcinoma

OBJECTIVES

To evaluate the impact of preoperative anemia and perioperative blood transfusion (PBT) on disease free (DFS) and overall survival (OS) of patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

Retrospective study of 354 patients primarily treated with surgery between 2006 and 2016. Cases were selected according to completeness and accuracy of available clinical data. Thus, a selection bias cannot be excluded. Patients who received PBT were identified by our controlling department and verified by our blood bank data base.

RESULTS

Both, preoperative anemia and PBT significantly decreased OS in univariate analysis. Although PBT was needed more frequently by older patients in worse physical conditions with more advanced HNSCC, subgroup analysis also demonstrate a profoundly negative effect of PBT on OS in younger patients and early stage HNSCC. According to a restrictive transfusion policy at our hospital the transfusion rate was comparably low. We could not verify increasing effects of PBT on cancer recurrence rates as it was previously shown.

DISCUSSION

Preoperative anemia is the most common paraneoplastic syndrome in HNSCC. Despite its devastating prognostic effect we suggest a restrictive transfusion policy whenever possible. Our data also show that anemia as an independent prognostic factor in head and neck surgical oncology is defined not only by low hemoglobin concentrations but low red blood cell counts as well.

Diagnostic, preventive and therapeutic evidence in obstetrics for the implementation of patient blood management: a systematic review protocol

INTRODUCTION

Patientblood management (PBM) is defined as the application of evidence-based diagnostic, preventive and therapeutic approaches designed to maintain haemoglobin concentration, optimise haemostasis and minimise blood loss in an effort to improve patient outcome. We propose a protocol for the assessment of the evidence of diagnostic, preventive and therapeutic approaches for the management of relevant outcomes in obstetrics with the aim to create a framework for PBM implementation.

METHODS AND ANALYSIS

Diagnostic, preventive and therapeutic tools will be considered in the gynaecological conditions and obstetrics setting (antenatal care, peripartum care and maternity care). For each condition, (1) clinical questions based on prioritised outcomes will be developed; (2) evidence will be retrieved systematically from electronic medical literature (MEDLINE, EMBASE, the Cochrane Library, Web of Science, and CINAHL); (3) quality of the reviews will be assessed using the AMSTAR (A Measurement Tool to Assess Systematic Reviews) checklist; quality of primary intervention studies will be assessed using the risk of bias tool (Cochrane method); quality of diagnostic primary studies will be assessed using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies); (4) the Grading of Recommendations Assessment, Development and Evaluation method will be applied to rate the quality of the evidence and to develop recommendations.

ETHICS AND DISSEMINATION

For each diagnostic, preventive or therapeutic intervention evaluated, a manuscript comprising the evidence retrieved and the recommendation produced will be provided and published in peer-reviewed journals. Ethical approval is not required.

Consensus Recommendations for RBC Transfusion Practice in Critically Ill Children From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To date, there are no published guidelines to direct RBC transfusion decision-making specifically for critically ill children. We present the recommendations from the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

Consensus conference series of multidisciplinary, international experts in RBC transfusion management of critically ill children.

SETTING

Not applicable.

INTERVENTION

None.

SUBJECTS

Children with, or children at risk for, critical illness who receive or are at risk for receiving a RBC transfusion.

METHODS

A panel of 38 content and four methodology experts met over the course of 2 years to develop evidence-based, and when evidence lacking, expert consensus-based recommendations regarding decision-making for RBC transfusion management and research priorities for transfusion in critically ill children. The experts focused on nine specific populations of critically ill children: general, respiratory failure, nonhemorrhagic shock, nonlife-threatening bleeding or hemorrhagic shock, acute brain injury, acquired/congenital heart disease, sickle cell/oncology/transplant, extracorporeal membrane oxygenation/ventricular assist/ renal replacement support, and alternative processing. Data to formulate evidence-based and expert consensus recommendations were selected based on searches of PubMed, EMBASE, and Cochrane Library from 1980 to May 2017. Agreement was obtained using the Research and Development/UCLA Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method.

MEASUREMENTS AND RESULTS

The Transfusion and Anemia Expertise Initiative consensus conference developed and reached consensus on a total of 102 recommendations (57 clinical [20 evidence based, 37 expert consensus], 45 research recommendations). All final recommendations met agreement, defined a priori as greater than 80%. A decision tree to aid clinicians was created based on the clinical recommendations.

CONCLUSIONS

The Transfusion and Anemia Expertise Initiative recommendations provide important clinical guidance and applicable tools to avoid unnecessary RBC transfusions. Research recommendations identify areas of focus for future investigation to improve outcomes and safety for RBC transfusion.

Risk factors for peripartum blood transfusion in South Africa: a case-control study

BACKGROUND

Obstetric hemorrhage (OH) and access to peripartum blood transfusion remains a global health challenge. The rates of peripartum transfusion in South Africa exceed those in high-income countries despite comparable rates of OH. We sought to evaluate factors associated with peripartum transfusion.

STUDY DESIGN AND METHODS

A case-control study was conducted at four large South African hospitals. Transfused peripartum women (cases) and nontransfused controls were stratum matched 1:2 by hospital and delivery date. Data on obstetric, transfusion, and human immunodeficiency virus (HIV) history were abstracted from medical records. Blood was obtained for laboratory evaluation. We calculated unadjusted and adjusted odds ratios (ORs) for transfusion using logistic regression.

RESULTS

A total of 1200 transfused cases and 2434 controls were evaluated. Antepartum hemorrhage (OR, 197.95; 95% confidence interval [CI], 104.27-375.78), hemorrhage with vaginal delivery (OR, 136.46; 95% CI, 75.87-245.18), prenatal anemia (OR, 22.76; 95% CI, 12.34-41.93 for prenatal hemoglobin level < 7 g/dL), and failed access to prenatal care (OR, 6.71; 95% CI, 4.32-10.42) were the major risk factors for transfusion. Platelet (PLT) count (ORs, 4.10, 2.66, and 1.77 for ≤50 × 109 , 51 × 109 -100 × 109 , and 101 × 109 -150 × 109 cells/L, respectively), HIV infection (OR, 1.29; 95% CI, 1.02-1.62), and admitting hospital (twofold variation) were also associated with transfusion. Mode of delivery, race, age category, gravidity, parity, gestational age, and birthweight were not independently associated with transfusion.

CONCLUSION

Major risk factors of peripartum transfusion in South Africa, namely, prenatal anemia and access to prenatal care, may be amenable to intervention. HIV infection and moderately low PLT count are novel risk factors that merit further investigation.

Prediction of readmissions in the first post-operative year following hip fracture surgery

PURPOSE

To define risk factors for rehospitalization following fragility hip fractures and to create a predictive model.

METHODS

A retrospective cohort study of patients 65 years and older, who were treated operatively following fragility hip fractures between 01.2011 and 06.2016. Patients were allocated into two study groups based on the occurrence of recurrent hospitalizations in the year following surgery. Demographic information, comorbidities, and in-hospital characteristics were collected, as was information regarding 1-year readmissions. Multivariate analysis of factors predictive of rehospitalizations was performed, followed by a logistic regression using all predictors with p < 0.05. A stepwise backwards elimination method was used to create the predictive model.

RESULTS

Eight hundred and fifty-one patients were included; 369 (43.4%) had recurrent hospitalizations within the first post-operative year. Patients who were rehospitalized were more likely to be males, to use a walking aid and to live dependently. They had a higher age-adjusted Charlson's comorbidity index (ACCI) score, a higher perveance of atrial fibrillation, lower hemoglobin, worse renal function, less platelets, and longer time to surgery. Prevalence of in-hospital complications was similar. Six variables were found to independently influence the chance for readmissions: male gender, the use of a walking aid, higher ACCI score, lower hemoglobin, atrial fibrillation, and a longer surgical delay. Only the first four were found to be adequate predictors and were added to the prediction formula.

CONCLUSION

High 1-year readmission rates are seen following discharge in patients with fragility hip fractures. Addressing risk factors might aid to better rehabilitate patients and reduce morbidity.

Red blood cell transfusion to treat or prevent complications in sickle cell disease: an overview of Cochrane reviews

BACKGROUND

Globally, sickle cell disease (SCD) is one of the commonest severe monogenic disorders, due to the inheritance of two abnormal haemoglobin (beta globin) genes. SCD can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Red blood cell (RBC) transfusions are used to treat complications of SCD, e.g. acute chest syndrome (ACS) (this often involves a single transfusion episode), or they can be part of a regular long-term transfusion programme to prevent SCD complications.

OBJECTIVES

To summarize the evidence in Cochrane Reviews of the effectiveness and safety of RBC transfusions versus no transfusion, or restrictive (to increase the total haemoglobin) versus liberal (to decrease the haemoglobin S level below a specified percentage) transfusion, for treating or preventing complications experienced by people with SCD.

METHODS

We included Cochrane Reviews of randomised or quasi-randomised controlled trials published in the Cochrane Database of Systematic Reviews, that addressed various SCD complications and had RBC transfusion as an intervention or comparator. We assessed the methodological quality of included reviews according to the AMSTAR quality assessment.

MAIN RESULTS

We included 15 Cochrane Reviews, 10 of which had no included studies with an RBC transfusion intervention (five reported RCTs with other interventions; and five contained no studies). Five of the 15 reviews included participants randomised to RBC transfusion, but in one of these reviews only 10 participants were randomised with no usable data. Four reviews (nine trials with 1502 participants) reported data comparing short- or long-term RBC transfusions versus standard care, disease-modifying agents, a restrictive versus a liberal transfusion strategy and long-term RBC transfusions versus transfusions to treat complications. All reviews were of high quality according to AMSTAR quality assessment, however, the quality of the included trials was highly variable across outcomes. Trials were downgraded according to GRADE methodology for risk of bias, indirectness (most trials were conducted in children with HbSS), and imprecision (outcomes had wide confidence intervals).In all four reviews and all comparisons there was little or no difference in the risk of death (very low-quality evidence). There were either no deaths or death was a rare event.Short-term RBC transfusion versus standard care (one review: two trials, 434 participants, GRADE very low- to low-quality evidence)In people undergoing low- to medium-risk surgery, RBC transfusions may decrease the risk of acute chest syndrome (ACS) in people with African haplotypes compared to standard care (low-quality evidence), but there was little or no difference in people with the Arabic haplotype (very-low quality evidence). There was also little or no difference in the risk of other SCD-related or transfusion-related complications (very-low quality evidence).Long-term RBC transfusion versus standard care (two reviews: three trials, 405 participants, very low- to moderate-quality evidence)In children and adolescents at high risk of stroke (abnormal transcranial doppler (TCD) velocities or silent cerebral infarct (SCI)), long-term RBC transfusions probably decrease the risk of stroke (moderate-quality evidence) and may decrease the risk of ACS and painful crisis compared to standard care (low-quality evidence). Long-term RBC transfusions may also decrease the risk of SCI in children with abnormal TCD velocities (low-quality evidence), but there may be little or no difference in the risk of SCI in children with normal TCD velocities and previous SCI (low-quality evidence).In children and adolescents already receiving long-term RBC transfusions for preventing stroke, in comparison to standard care, continuing long-term RBC transfusions may reduce the risk of SCI (low-quality evidence) but we do not know whether there is a difference in the risk of stroke (very-low quality evidence). In children with normal TCD velocities and SCI there was little or no difference in the risk of alloimmunisation or transfusion reactions, but RBC transfusions may increase the risk of iron overload (low-quality evidence).Long-term RBC transfusion versus RBC transfusion to treat complications (one review: one trial, 72 participants, very low- to low-quality evidence)In pregnant women, long-term RBC transfusions may decrease the risk of painful crisis compared to transfusion for complications (low-quality evidence); but there may be little or no difference in the risk of other SCD-related complications or transfusion reactions (very-low quality evidence).RBC transfusion versus disease-modifying agents (hydroxyurea) (two reviews: two trials; 254 participants, very low- to low-quality evidence)For primary prevention of stroke in children, with abnormal TCD and no severe vasculopathy on magnetic resonance imaging/magnetic resonance angiography (MRI/MRA), who have received at least one year of RBC transfusions, we do not know whether there is a difference between RBC transfusion and disease-modifying agents in the risk of stroke; SCI; ACS; or painful crisis (very-low quality evidence). There may be little or no difference in the risk of iron overload (low-quality evidence).Similarly, for secondary prevention of stroke in children and adolescents, we do not know whether there is a difference between these interventions in the risk of stroke; SCI; or ACS (very-low quality evidence); but hydroxyurea with phlebotomy may increase the risk of painful crisis and global SCD serious adverse events compared to RBC transfusion (low-quality evidence). There may be little or no difference in the risk of iron overload (low-quality evidence).Restrictive versus liberal RBC transfusion strategy (one review: one trial; 230 participants, very low-quality evidence)In people undergoing cholecystectomy, there was little or no difference between strategies in the risk of SCD-related or transfusion-related complications (very-low quality evidence).

AUTHORS' CONCLUSIONS

This overview provides support from two high-quality Cochrane Reviews for the use of RBC transfusions in preventing stroke in children and adolescents at high risk of stroke (abnormal TCDs or SCI) and evidence that it may decrease the risk of SCI in children with abnormal TCD velocities. In addition RBC transfusions may reduce the risk of ACS and painful crisis in this population.This overview highlights the lack of high-quality evidence in adults with SCD and the number of reviews that have no evidence for the use of RBC transfusions across a spectrum of SCD complications. Also of concern is the variable and often incomplete reporting of patient-relevant outcomes in the included trials such as SCD-related serious adverse events and quality of life.

Red blood cell transfusion in patients with ST-elevation myocardial infarction-a meta-analysis of more than 21,000 patients

BACKGROUND

Red blood cell transfusion remains controversial in patients with acute coronary syndromes and particularly in patients with ST-elevation myocardial infarction (STEMI).

METHODS

We systematically searched PubMed, Cochrane, EMBASE, and Web of Science for studies published until January 2017 describing the outcomes in patients with STEMI who received red blood cell transfusion, compared with patients who did not.

RESULTS

A total of 21,770 patients with STEMI from 5 cohort studies were included in the meta-analysis, 984 (4.5%) received red blood cell transfusion and 20,786 (95.4%) did not. Red blood cell transfusion was associated with a higher risk of in-hospital and long-term mortality, emergency repeated percutaneous coronary intervention (PCI), reinfarction rate, stroke rate, and heart failure. The group with red blood cell transfusion had a slightly higher incidence of diabetes mellitus and hypertension, but a lower incidence of smoking. The two groups had the same incidence of prior myocardial infarction, prior coronary artery bypass graft surgery and malignancy. Prior heart failure, prior stroke and prior PCI were more frequent in the group that had received red blood cell transfusion. The mean nadir haemoglobin was 8.5 ± 0.1 g/dl in the group with red blood cell transfusion and 12.5 ± 0.4 g/dl in the control group, p < 0.001.

CONCLUSIONS

Red blood cell transfusion increases the morbidity and mortality in patients with STEMI. This difference could not be explained by the higher morbidity in the red blood cell transfusion group alone. Further randomised controlled trials are required to provide a reliable haemoglobin threshold for these patients.

Red blood cell transfusion policy: a critical literature review

The issue of the most appropriate red blood cell transfusion policy has been addressed by a number of randomised controlled trials, conducted over the last decades, comparing the effects on patients' outcome of restrictive blood transfusion strategies (transfusing when the haemoglobin concentration is less than 7 g/dL to 8 g/dL) vs more liberal ones (transfusing when the haemoglobin concentration is less than 9 g/dL to 10 g/dL) in a variety of clinical settings. In parallel, various systematic reviews and meta-analyses have tried to perform pooled analyses of the data from these randomised controlled trials and their results have been utilised by scientific societies to provide recommendations and guidelines on red blood cell transfusion thresholds. All these aspects will be critically discussed in this narrative review.

Anaemia and transfusion triggers in critically ill patients - What we have learnt thus far

Anaemia is a common finding in critically ill patients, the cause of which is multi-factorial including: sepsis, haemolysis (and disseminated intravascular coagulation), iatrogenic blood loss secondary to laboratory sampling, post-operative anaemia, bone marrow suppression/failure, decreased production of erythropoietin, anaemia secondary to drugs/toxins, overt or occult blood loss, functional iron deficiency, poor nutrition and haemodilution. Anaemia is associated with deleterious outcomes including increased risk of cardiac-related morbidity and mortality and decrease in oxygen-carrying capacity in the face of increased metabolic demands. There is a growing body of evidence, which demonstrates that packed red blood cell transfusions are associated with poorer outcomes. Clinicians therefore need to weigh the potential benefit of treating anaemia against the desire to avoid unnecessary transfusions. We explored current literature regarding transfusion triggers and morbidity and mortality associated with packed red blood cell transfusions transfusion, concentrating on studies that have been conducted in critical care patients. In addition, we reflected on trials which considered the viability of iron transfusion and erythropoietin in critically unwell patients.

Introduction of national guidelines for restrictive blood transfusion threshold for hip fracture patients--a consecutive cohort study based on complete follow-up in national databases

Background

Randomized controlled trials have demonstrated that a restrictive red blood cell (RBC) transfusion strategy lowers transfusion frequency without affecting mortality. However, the external validity of these trials has not been tested in a large cohort. The purpose was to estimate the effect of introducing a National Clinical Guideline (NCG) for a restrictive hemoglobin transfusion threshold on transfusion frequency and mortality in hip fracture patients > 65 years old.

Methods

A consecutive cohort study of hip fracture patients > 65 years old residing in the southern region of Denmark was conducted using prospectively gathered data from registers during two separate 1-year time periods. The first period from October 1, 2012, to September 30, 2013, included 1494 patients and used a liberal transfusion threshold, whereas the second period from October 1, 2015, to September 30, 2016, including 1414 participants used a restrictive threshold from the NCG. Participant data for age, sex, body mass index, Charlson Comorbidity Index, time to surgery, and death were retrieved from the Danish Interdisciplinary Registry of Hip Fractures and were merged with RBC transfusion and medication data extracted from the Danish Transfusion and Odense Pharmacoepidemiological Databases, respectively. Cox proportional hazards models were used to test relative mortality risk for the restrictive group compared with the liberal group at 30 and 90 days.

Results

Overall RBC transfusions decreased from 42 to 30% (p < 0.001). The 30-day mortality rate (95% CI) was 9% (8;11) in the restrictive group and 13% (11;14) in the liberal group (p < 0.008), whereas the adjusted relative mortality risk was 0.72 (0.57;0.91). The 90-day mortality rate was 15% (13;17) in the restrictive group and 19% (17;21) in the liberal group, whereas the adjusted relative mortality risk was 0.78 (0.65;0.94).

Conclusion

These data suggest that the introduction of an NCG on restrictive blood transfusion leads to lower transfusion frequency in hip fracture patients > 65 years old. Even though this reduction is associated with decreased mortality at both 30 and 90 days, it may be explained by other issues than restrictive transfusion strategy. There has been an improvement in the mortality of hip fracture patients in Denmark, and we suggest that a restrictive transfusion strategy does not lead to increased mortality.

Behaviour modification interventions to optimise red blood cell transfusion practices: a systematic review and meta-analysis

OBJECTIVE

To assess the impact of behaviour modification interventions to promote restrictive red blood cell (RBC) transfusion practices.

DESIGN

Systematic review and meta-analysis.

SETTING, PARTICIPANTS, INTERVENTIONS

Seven electronic databases were searched to January 2018. Published randomised controlled trials (RCTs) or non-randomised studies examining an intervention to modify healthcare providers' RBC transfusion practice in any healthcare setting were included.

PRIMARY AND SECONDARY OUTCOMES

The primary outcome was the proportion of patients transfused. Secondary outcomes included the proportion of inappropriate transfusions, RBC units transfused per patient, in-hospital mortality, length of stay (LOS), pretransfusion haemoglobin and healthcare costs. Meta-analysis was conducted using a random-effects model and meta-regression was performed in cases of heterogeneity. Publication bias was assessed by Begg's funnel plot.

RESULTS

Eighty-four low to moderate quality studies were included: 3 were RCTs and 81 were non-randomised studies. Thirty-one studies evaluated a single intervention, 44 examined a multimodal intervention. The comparator in all studies was standard of care or historical control. In 33 non-randomised studies, use of an intervention was associated with reduced odds of transfusion (OR 0.63 (95% CI 0.56 to 0.71)), odds of inappropriate transfusion (OR 0.46 (95% CI 0.36 to 0.59)), RBC units/patient weighted mean difference (WMD: -0.50 units (95% CI -0.85 to -0.16)), LOS (WMD: -1.14 days (95% CI -2.12 to -0.16)) and pretransfusion haemoglobin (-0.28 g/dL (95% CI -0.48 to -0.08)). There was no difference in odds of mortality (OR 0.90 (95% CI 0.80 to 1.02)). Protocol/algorithm and multimodal interventions were associated with the greatest decreases in the primary outcome. There was high heterogeneity among estimates and evidence for publication bias.

CONCLUSIONS

The literature examining the impact of interventions on RBC transfusions is extensive, although most studies are non-randomised. Despite this, pooled analysis of 33 studies revealed improvement in the primary outcome. Future work needs to shift from asking, 'does it work?' to 'what works best and at what cost?'

PROSPERO REGISTRATION NUMBER

CRD42015024757.

Red Blood Cell Transfusions Following Resection of Skull Base Meningiomas: Risk Factors and Clinical Outcomes

Objective  This article identifies risk factors for and investigates clinical outcomes of postoperative red blood cell transfusion in patients with skull base meningiomas. Design  Retrospective cohort study. Setting  Single academic medical center. Participants  The transfusion group included patients who had skull base meningiomas and who received packed red blood cell (RBC) transfusion within 7 days of surgery. The no transfusion group included patients who had skull base meningiomas but who did not have RBCs transfused within 7 days of surgery. Main Outcome Measures  In-hospital complication rate, length of stay (LOS), and discharge disposition. Results  One hundred and ninety-six patients had a craniotomy for resection of a meningioma at our institution from March 2013 to January 2017. Seven patients had skull base meningiomas and received RBC transfusion within 7 days of surgery (the transfusion group). The skull base was an independent risk factor for transfusion after we controlled for the effect of meningioma size (OR 3.89, 95% CI 1.34, 11.25). Operative time greater than 10 hours was an independent risk factor for prolonged hospital stay (OR 8.84, 95% CI 1.08, 72.10) once we controlled for the effect of transfusion. In contrast, transfusion did not independently impact LOS or discharge disposition once we controlled for the effect of operative time. Conclusions  The skull base is an independent predictor of RBC transfusion. However, RBC transfusion alone cannot predict LOS or discharge disposition in patients who undergo surgical resection of a skull base meningioma.

[Abnormal laboratory results : Plausibility, reliability, and implications]

In outpatient care or the emergency room laboratory tests oftentimes provide the first clues to the medical condition that made the patient seek medical help. Quite commonly, rapid medical decisions are required in these situations. Therefore, laboratory results must be evaluated immediately and interpreted within the broader context of the patient's presentation. During this process test results must be checked for plausibility, their positive and/or negative predictive values for the individual patient must be considered, and finally, the potential clinical implications need to be assessed. The latter in particular is of the utmost importance. This article discusses several laboratory tests commonly ordered for emergency patients and provides some guidance on their relevance in the decision to refer an outpatient to an emergency room or for inpatient care, or whether a patient can be safely diagnosed in the outpatient setting.

Perioperative Blood Management Strategies for Total Knee Arthroplasty

Total knee arthroplasty (TKA) often causes a significant amount of blood loss with an accompanying decline in hemoglobin and may increase the frequency of allogeneic blood transfusion rates. Unfortunately, allogeneic blood transfusions have associated risks including postoperative confusion, infection, cardiac arrhythmia, fluid overload, increased length of hospital stay, and increased mortality. Other than reducing the need for blood transfusions, reducing perioperative blood loss in TKA may also minimize intra-articular hemorrhage, limb swelling, and postoperative pain, and increase the range of motion during the early postoperative period. These benefits improve rehabilitation success and increase patients' postoperative satisfaction. Preoperative anemia, coupled with intraoperative and postoperative blood loss, is a major factor associated with higher rates of blood transfusion in TKA. Thus, treatment of preoperative anemia and prevention of perioperative blood loss are the primary strategies for perioperative blood management in TKA. This review, combined with current evidence, analyzes various methods of blood conservation, including preoperative, intraoperative, and postoperative methods, in terms of their effectiveness, safety, and cost. Because many factors can be controlled to reduce blood loss and transfusion rates in TKA, a highly efficient, safe, and cost-effective blood management strategy can be constructed to eliminate the need for transfusions associated with TKA.

Transfusion practice patterns in patients with anemia receiving myelosuppressive chemotherapy for nonmyeloid cancer: results from a prospective observational study

Purpose

The decision to prescribe packed red blood cell (PRBC) transfusions in patients with chemotherapy-induced anemia (CIA) includes assessment of clinical features such as the patient’s cancer type and treatment regimen, severity of anemia symptoms, and presence of comorbidities. We examined contemporary transfusion practices in patients with nonmyeloid cancer and CIA.

Methods

Key inclusion criteria were age ≥ 18 years with nonmyeloid cancer, receiving first/second-line myelosuppressive chemotherapy, baseline hemoglobin (Hb) ≤ 10.0 g/dL, and planned to receive ≥ 1 PRBC transfusions. Exclusion criteria were receipt of erythropoiesis-stimulating agents within 8 weeks of screening and/or chronic renal insufficiency. Data were collected from patients’ medical records, laboratory values, and physician/provider questionnaires. Proportion of patients for each clinical consideration leading to a decision to prescribe a PRBC transfusion and 95% exact binomial confidence intervals were determined.

Results

The study enrolled 154 patients at 18 sites in USA; 147 (95.5%) received a PRBC transfusion. Fatigue was the most common symptom affecting the decision to prescribe a PRBC transfusion (101 [69.2%] patients). Of the three reasons selected as primary considerations for prescribing a PRBC transfusion, anemia symptoms (106 [72.1%] patients) was the most frequently reported, followed by Hb value (37 [25.2%] patients) and medical history (4 [2.7%] patients).

Conclusions

In this study, the primary consideration for prescribing a PRBC transfusion was anemia symptoms in 72.1% of patients, with only 25.2% of patients prescribed a transfusion based exclusively on Hb value. Results indicate that clinical judgment and patient symptoms, not just Hb value, were used in decisions to prescribe PRBC transfusions.

Electronic supplementary material

The online version of this article (10.1007/s00520-017-4035-7) contains supplementary material, which is available to authorized users.

Risk of Acute Kidney Injury in Patients Randomized to a Restrictive Versus Liberal Approach to Red Blood Cell Transfusion in Cardiac Surgery: A Substudy Protocol of the Transfusion Requirements in Cardiac Surgery III Noninferiority Trial

Background:

When safe to do so, avoiding blood transfusions in cardiac surgery can avoid the risk of transfusion-related infections and other complications while protecting a scarce resource and reducing costs. This protocol describes a kidney substudy of the Transfusion Requirements in Cardiac Surgery III (TRICS-III) trial, a multinational noninferiority randomized controlled trial to determine whether the risk of major clinical outcomes in patients undergoing planned cardiac surgery with cardiopulmonary bypass is no greater with a restrictive versus liberal approach to red blood cell transfusion.

Objective:

The objective of this substudy is to determine whether the risk of acute kidney injury is no greater with a restrictive versus liberal approach to red blood cell transfusion, and whether this holds true in patients with and without preexisting chronic kidney disease.

Design and Setting:

Multinational noninferiority randomized controlled trial conducted in 73 centers in 19 countries (2014-2017).

Patients:

Patients (~4800) undergoing planned cardiac surgery with cardiopulmonary bypass.

Measurements:

The primary outcome of this substudy is perioperative acute kidney injury, defined as an acute rise in serum creatinine from the preoperative value (obtained in the 30-day period before surgery), where an acute rise is defined as ≥26.5 μmol/L in the first 48 hours after surgery or ≥50% in the first 7 days after surgery.

Methods:

We will report the absolute risk difference in acute kidney injury and the 95% confidence interval. We will repeat the primary analysis using alternative definitions of acute kidney injury, including staging definitions, and will examine effect modification by preexisting chronic kidney disease (defined as a preoperative estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m²).

Limitations:

It is not possible to blind patients or providers to the intervention; however, objective measures will be used to assess outcomes, and outcome assessors will be blinded to the intervention assignment.

Results:

Substudy results will be reported by the year 2018.

Conclusions:

This substudy will provide generalizable estimates of the risk of acute kidney injury of a restrictive versus liberal approach to red blood cell transfusion in the presence of anemia during cardiac surgery done with cardiopulmonary bypass.

Trial Registration:

www.clinicaltrials.gov; clinical trial registration number NCT 02042898.

Transfusion Thresholds for Major Orthopedic Surgery: A Systematic Review and Meta-analysis

BACKGROUND

More than a million surgeries are performed annually in the United States for hip or knee arthroplasty or hip fracture stabilization. One-fifth of these patients have blood transfusions during their hospital stay. Increases in transfusion rates have caused concern about increased adverse events from unnecessary transfusions.

METHODS

We systematically reviewed randomized trials examining the effect of restrictive vs liberal transfusion thresholds on patients having major orthopedic surgery. Study results were meta-analyzed with a random-effects model and heterogeneity was tested with the I² statistic. Study risk of bias was assessed using a modified Jadad scale and evidence strength was measured using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system.

RESULTS

A total of 504 published articles were screened, and 15 met inclusion criteria. The articles described 9 randomized trials, most comparing transfusion thresholds of 8 vs 10 g/dL hemoglobin. All involved hip or knee arthroplasty and/or hip fracture patients. Moderate-strength evidence suggested a reduction in need for transfusion (relative risk, 0.53; 95% confidence interval [CI], 0.39-0.71; I² = 95%) and mean number of units transfused (-0.95 units, 95% CI, -1.48 to -0.41, I² = 98%). There was a possible reduction in overall infections with more restrictive transfusion thresholds, although the result was not statistically significant (relative risk, 0.71; 95% CI, 0.47-1.06; I² = 54%). Moderate-strength evidence suggested no differences in other clinical outcomes between the groups. Limitations included incomplete blinding, inconsistency, and imprecision.

CONCLUSION

Moderate-strength evidence suggests that restrictive transfusion practices reduce utilization of transfusions and may decrease infections without increasing adverse outcomes in major orthopedic surgery.

Red blood cell transfusion in the resuscitation of septic patients with hematological malignancies

BACKGROUND

Indications for red blood cell (RBC) transfusion in septic acute circulatory failure remain unclear. We addressed the practices and the prognostic impact of RBC transfusion in the early resuscitation of severe sepsis and septic shock in patients with hematological malignancies.

METHODS

We performed a retrospective analysis of a prospectively collected database of patients with hematological malignancies who required intensive care unit (ICU) admission in 2010-2011. Patients with a main admission diagnosis of severe sepsis or septic shock were included in the present study. We assessed RBC transfusion during the first two days as part of initial resuscitation.

RESULTS

Among the 1011 patients of the primary cohort, 631 (62.4%) were admitted to the ICU for severe sepsis (55%) or septic shock (45%). Among them, 210 (33.3%) patients received a median of 2 [interquartile 1-3] packed red cells during the first 48 h. Hemoglobin levels were lower in transfused patients at days 1 and 2 and became similar to those of non-transfused patients at day 3. Early RBC transfusion was more likely in patients with myeloid neoplasms and neutropenia. Transfused patients displayed more severe presentations as assessed by higher admission SOFA scores and blood lactate levels and the further requirements for organ failure supports. RBC transfusion within the first two days was associated with higher day 7 (20.5 vs. 13.3%, p = 0.02), in-ICU (39 vs. 25.2%, p < 0.001) and in-hospital (51 vs. 36.6%, p < 0.001) mortality rates. RBC transfusion remained independently associated with increased in-hospital mortality in multivariate logistic regression (OR 1.52 [1.03-2.26], p = 0.03) and propensity score-adjusted (OR 1.64 [1.05-2.57], p = 0.03) analysis.

CONCLUSIONS

RBC transfusion is commonly used in the early resuscitation of septic patients with hematological malignancies. Although it was preferentially provided to the most severe patients, we found it possibly associated with an increased risk of death.

Common Sense Approach to Managing Sepsis

Sepsis results in many deaths, prolonged suffering among survivors and relatives, and high use of resources both in developed and developing countries. The updated Surviving Sepsis Campaign guidelines should aid clinicians in improving the identification and management of these patients, but many uncertainties remain because most of the guidance is based on low-quality evidence. This article discusses how to use some of the specific items of the guidelines together with a common-sense approach to aid clinical management of patients with sepsis while trying to balance the potential benefit and harm of the items.

Transfusion Requirement in Burn Care Evaluation (TRIBE): A Multicenter Randomized Prospective Trial of Blood Transfusion in Major Burn Injury

OBJECTIVE

Our objective was to compare outcomes of a restrictive to a liberal red cell transfusion strategy in 20% or more total body surface area (TBSA) burn patients. We hypothesized that the restrictive group would have less blood stream infection (BSI), organ dysfunction, and mortality.

BACKGROUND

Patients with major burns have major (>1 blood volume) transfusion requirements. Studies suggest that a restrictive blood transfusion strategy is equivalent to a liberal strategy. However, major burn injury is precluded from these studies. The optimal transfusion strategy in major burn injury is thus needed but remains unknown.

METHODS

This prospective randomized multicenter trial block randomized patients to a restrictive (hemoglobin 7-8 g/dL) or liberal (hemoglobin 10-11 g/dL) transfusion strategy throughout hospitalization. Data collected included demographics, infections, transfusions, and outcomes.

RESULTS

Eighteen burn centers enrolled 345 patients with 20% or more TBSA burn similar in age, TBSA burn, and inhalation injury. A total of 7054 units blood were transfused. The restrictive group received fewer blood transfusions: mean 20.3 ± 32.7 units, median = 8 (interquartile range: 3, 24) versus mean 31.8 ± 44.3 units, median = 16 (interquartile range: 7, 40) in the liberal group (P < 0.0001, Wilcoxon rank sum). BSI incidence, organ dysfunction, ventilator days, and time to wound healing (P > 0.05) were similar. In addition, there was no 30-day mortality difference: 9.5% restrictive versus 8.5% liberal (P = 0.892, χ test).

CONCLUSIONS

A restrictive transfusion strategy halved blood product utilization. Although the restrictive strategy did not decrease BSI, mortality, or organ dysfunction in major burn injury, these outcomes were no worse than the liberal strategy (Clinicaltrials.gov identifier NCT01079247).

Risk Factors Associated with Perioperative Myocardial Infarction in Major Open Vascular Surgery

BACKGROUND

Among patients undergoing noncardiac surgery, major vascular surgery is associated with a high risk of perioperative myocardial infarction (MI). Currently, there are no perioperative MI risk calculators accounting for intraoperative and postoperative risk factors in vascular surgery patients. We aimed to investigate specific risk factors for perioperative MI after major open vascular surgery to determine which patients are at highest risk of MI and the association of perioperative MI with perioperative transfusion.

METHODS

This statewide, retrospective cohort study analyzed risk factors for perioperative MI in major open vascular surgery between July 2012 and December 2015 using the Michigan Surgical Quality Collaborative, a multicenter quality collaborative. Patients were identified using current procedure terminology codes including open abdominal aortic aneurysm repairs (oAAA), aortobifemoral bypasses (AFB), and lower extremity bypasses (LEB). Rates of myocardial infarction were described for each procedure. A priori, preoperative, intraoperative, and postoperative variables were evaluated using univariate and multivariable statistics after adjusting for intraoperative factors including anesthesia type, intraoperative blood loss, intraoperative transfusion, and intraoperative vasopressor medications.

RESULTS

A total of 3,689 patients underwent major open vascular surgery, including 375 oAAA, 392 AFB, and 2,922 LEB procedures. The overall incidence of MI was 2.4%, varying from 1.8% for aortobifemoral bypass, 2.4% for lower extremity bypass, and 3.7% for open abdominal aortic aneurysm repair. Although preoperative risk factors for myocardial infarction included age, American Society of Anesthesiologists score, diabetes, coronary artery disease, congestive heart failure, use of beta blocker, lower preoperative hematocrit, and surgical priority (urgent/emergent cases), after adjusting for intraoperative risk factors, all preoperative risk factors were not significant with the exception of surgical priority. After adjusting for intraoperative factors, only surgical priority (odds ratio [OR] = 1.70, 95% confidence interval [CI] [1.01-2.85], P < 0.001) and postoperative transfusion (OR = 2.65, 95% CI [1.59-4.44], P < 0.001) was associated with myocardial infarction, and higher nadir hematocrit was inversely associated with myocardial infarction (OR = 0.89, 95% CI [0.85-0.94], P < 0.001).

CONCLUSIONS

Among vascular surgery patients undergoing major open vascular surgery, surgical priority was the only preoperative risk factors independently associated with MI, and only postoperative variables such as nadir hematocrit and postoperative transfusion were associated with MI. This suggests minimizing intraoperative blood loss and prioritizing early intraoperative transfusion may be the potential targets for process improvement.

Harms of off-label erythropoiesis-stimulating agents for critically ill people

BACKGROUND

Anaemia is a common problem experienced by critically-ill people. Treatment with erythropoiesis-stimulating agents (ESAs) has been used as a pharmacologic strategy when the blunted response of endogenous erythropoietin has been reported in critically-ill people. The use of ESAs becomes more important where adverse clinical outcomes of transfusing blood products is a limitation. However, this indication for ESAs is not licensed by regulatory authorities and is called off-label use. Recent studies concern the harm of ESAs in a critical care setting.

OBJECTIVES

To focus on harms in assessing the effects of erythropoiesis-stimulating agents (ESAs), alone or in combination, compared with placebo, no treatment or a different active treatment regimen when administered off-label to critically-ill people.

SEARCH METHODS

We conducted a systematic search of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO via OvidSP, CINAHL, all evidence-based medicine (EBM) reviews including IPA and SCI-Expanded, Conference Proceedings Citation Index- Science, BIOSIS Previews and TOXLINE up to February 2017. We also searched trials registries, checked reference lists of relevant studies and tracked their citations by using SciVerse Scopus.

SELECTION CRITERIA

We considered randomized controlled trials (RCTs) and controlled observational studies, which compared scheduled systemic administration of ESAs versus other effective interventions, placebo or no treatment in critically-ill people.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and evaluated the eligibility of retrieved records, extracted data and assessed the risks of bias and quality of the included studies. We resolved differences in opinion by consensus or by involving a third review author. We assessed the evidence using GRADE and created a 'Summary of findings' table. We used fixed-effect or random-effects models, depending on the heterogeneity between studies. We fitted three-level hierarchical Bayesian models to calculate overall treatment effect estimates.

MAIN RESULTS

Of the 27,865 records identified, 39 clinical trials and 14 observational studies, including a total of 945,240 participants, were eligible for inclusion. Five studies are awaiting classification. Overall, we found 114 adverse events in 33 studies (30 RCTs and three observational studies), and mortality was reported in 41 studies (32 RCTs and nine observational studies). Most studies were at low to moderate risk of bias for harms outcomes. However, overall harm assessment and reporting were of moderate to low quality in the RCTs, and of low quality in the observational studies. We downgraded the GRADE quality of evidence for venous thromboembolism and mortality to very low and low, respectively, because of risk of bias, high inconsistency, imprecision and limitations of study design.It is unclear whether there is an increase in the risk of any adverse events (Bayesian risk ratio (RR) 1.05, 95% confidence interval (CI) 0.93 to 1.21; 3099 participants; 9 studies; low-quality evidence) or venous thromboembolism (Bayesian RR 1.04, 95% CI 0.70 to 1.41; 18,917 participants; 18 studies; very low-quality evidence).There was a decreased risk of mortality with off-label use of ESAs in critically-ill people (Bayesian RR 0.76, 95% CI 0.61 to 0.92; 930,470 participants; 34 studies; low-quality evidence).

AUTHORS' CONCLUSIONS

Low quality of evidence suggests that off-label use of ESAs may reduce mortality in a critical care setting. There was a lack of high-quality evidence about the harm of ESAs in critically-ill people. The information for biosimilar ESAs is less conclusive. Most studies neither evaluated ESAs' harm as a primary outcome nor predefined adverse events. Any further studies of ESA should address the quality of evaluating, recording and reporting of adverse events.

The Effect of Blood Transfusion on Outcomes in Aortic Surgery

The use of blood transfusion in cardiac surgery varies widely. The beneficial effects of blood products are offset by an increase in morbidity and mortality. Despite multiple studies showing an association between blood product exposure and adverse short- and long-term events, it is difficult to determine causality. Nevertheless, the implication is sufficient to warrant the search for alternative strategies to reduce the use of blood products while providing a standard of care that optimizes postoperative outcomes. Aortic surgery, in particular, is associated with an increased risk of bleeding requiring a blood transfusion. There is a paucity of evidence within aortic surgery regarding the deleterious effects of blood products. Here, we review the current evidence regarding patient outcomes after blood transfusion in cardiac surgery, with special emphasis on aortic surgery.