Decreased red blood cell use and mortality in hospitalized patients

Variation in Neonatal Transfusion Practice

OBJECTIVE

To estimate the incidence of blood product transfusion, including red blood cells, platelets, and plasma, and characterize pretransfusion hematologic values for infants during their initial hospitalization after birth.

STUDY DESIGN

Retrospective cohort study using data from 7 geographically diverse US academic and community hospitals that participated in the National Heart Lung and Blood Institute Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) from 2013 to 2016. Pretransfusion hematologic values were evaluated closest to each transfusion and no more than 24 hours beforehand.

RESULTS

Data from 60 243 infants were evaluated. The incidence of any transfusion differed by gestational age (P < .0001), with 80% (95% CI 76%-84%) transfused at <27 weeks of gestation (n = 329) and 0.5% (95% CI 0.5%-0.6%) transfused at ≥37 weeks of gestation (n = 53 919). The median pretransfusion hemoglobin was 11.2 g/dL (10th-90th percentile 8.8-14.1) for the entire cohort, ranging from 10.5 g/dL (8.8-12.3) for infants born extremely preterm at <27 weeks of gestation to 13.0 g/dL (10.5-15.5) for infants born at term. The median pretransfusion platelet count (×10⁹/L) was 71 (10th-90th percentile 26-135) for the entire cohort, and was >45 for all gestational age groups examined. The median pretransfusion international normalized ratio for the entire cohort was 1.7 (10th-90th percentile 1.2-2.8).

CONCLUSIONS

There is wide variability in pretransfusion hemoglobin, platelet count, and international normalized ratio values for neonatal transfusions. Our findings suggest that a large proportion of neonatal transfusions in the US are administered at thresholds greater than supported by the best-available evidence and highlight an opportunity for improved patient blood management.

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.

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.

Factors associated with red blood cell, platelet, and plasma transfusions among inpatient hospitalizations: a nationally representative study in the United States

BACKGROUND

Demographic and hospital-level factors associated with red blood cell (RBC), plasma, and platelet transfusions in hospitalized patients across the U.S. are not well characterized.

METHODS

We conducted a retrospective analysis of the National Inpatient Sample (2014). The unit of analysis was a hospitalization; sampling weights were applied to generate nationally-representative estimates. The primary outcome was having ≥ 1 RBC transfusion procedure; plasma and platelet transfusions were similarly assessed as secondary outcomes. For each component, factors associated with transfusion were measured using adjusted prevalence ratios (adjPR) and 95% confidence intervals (95% CI) estimated by multivariable Poisson regression.

RESULTS

The prevalence of RBC, plasma, and platelet transfusion was 5.8%, 0.9%, and 0.7%, respectively. RBC transfusions were associated with older age (≥ 65 vs. < 18 years; adjPR = 1.80; 95% CI = 1.66-1.96), female sex (adjPR = 1.13; 95% CI = 1.12-1.14), minority race/ethnic status, and hospitalizations in rural hospitals compared to urban teaching hospitals. Prevalence of RBC transfusion was lower among hospitalizations in the Midwest compared to the Northeast (adjPR = 0.73; 95% CI = 0.67-0.80). All components were more likely to be transfused in patients with a primary hematologic diagnosis, patients with a higher number of total diagnoses, patients who experienced a higher number of other procedures, and patients who eventually died in the hospital. In contrast to RBC transfusions, prevalence of platelet transfusion was greater in urban teaching hospitals (vs. rural; adjPR = 1.71; 95% CI = 1.49-1.98) and lower in blacks (vs. whites; adjPR = 0.80; 95% CI = 0.76-0.85).

CONCLUSIONS

Nationally, there is heterogeneity in factors associated with transfusion between each blood component, including by hospital type and location. This variability presents patient blood management programs with potential opportunities to reduce transfusions.

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.

Red blood cell transfusion and outcomes in acute pulmonary embolism

BACKGROUND AND OBJECTIVE

Blood transfusion has been associated with adverse outcomes in certain conditions. This study investigates the prevalence and outcomes of red blood cell (RBC) transfusion in patients with acute pulmonary embolism (PE).

METHODS

Retrospective study of consecutive patients from 2000 to 2012 admitted to a tertiary hospital with a primary diagnosis of acute PE. Transfusion status during the hospital admission was ascertained. Mortality was tracked from a state-wide death database and analysed using multivariable modelling.

RESULTS

A total of 73 patients (5% of all patients admitted with PE) received RBC transfusion during their admission. These patients were significantly older, had more co-morbidities, worse haemodynamics, higher simplified pulmonary embolism severity index scores, and lower plasma sodium and haemoglobin (Hb) levels at admission. Unadjusted mortality for the transfused group was significantly higher at 30-day (19% vs 4%, P < 0.001) and 6-month (40% vs 10%, P < 0.001) follow-up. Multivariable modelling showed RBC transfusion to be a significant independent predictor of mortality at 30-day (odds ratio 3.06, 95% CI: 1.17-8.01, P = 0.02) and 6-month (hazard ratio (HR) 1.97, 95% CI: 1.12-3.46, P = 0.02). Sensitivity analysis confirmed that transfused patients had higher mortality than non-transfused patients in the subgroup of patients with Hb <100 g/L.

CONCLUSION

RBC transfusion in patients hospitalized with acute PE is rare and appears to be associated with increased risk of short- and long-term mortality, independent of Hb level on admission. This finding underscores the need for future randomized controlled studies on the impact of RBC transfusion in the management of patients admitted with acute PE. [Correction added on 4 May 2018, after first online publication: the word 'serum' was changed to 'plasma' throughout the article where appropriate.].

Contemporary Risk Factors and Outcomes of Transfusion-Associated Circulatory Overload

OBJECTIVES

Transfusion-associated circulatory overload is characterized by hydrostatic pulmonary edema following blood transfusion. Restrictive transfusion practice may affect the occurrence and severity of transfusion-associated circulatory overload in critically ill patients. We sought to examine contemporary risk factors and outcomes for transfusion-associated circulatory overload.

DESIGN

Case-control study.

SETTING

Four tertiary care hospitals.

PATIENTS

We prospectively enrolled 200 patients with transfusion-associated circulatory overload identified by active surveillance and 405 controls matched by transfusion intensity.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Among 20,845 transfused patients who received 128,263 blood components from May 2015 until July 2016, transfusion-associated circulatory overload incidence was one case per 100 transfused patients. In addition to cardiovascular comorbidities, multivariable analysis identified the following independent predictors of transfusion-associated circulatory overload: acute kidney injury, emergency surgery, pretransfusion diuretic use, and plasma transfusion-the latter especially in females. Compared with matched controls, transfusion-associated circulatory overload cases were more likely to require mechanical ventilation (71% vs 49%; p < 0.001), experienced longer intensive care and hospital lengths of stay following transfusion, and had higher mortality (21% vs 11%; p = 0.02) even after adjustment for other potentially confounding variables.

CONCLUSIONS

Despite restrictive transfusion practice, transfusion-associated circulatory overload remains a frequent complication of transfusion and is an independent risk factor for in-hospital morbidity and mortality. In addition to cardiovascular and renal risk factors, plasma transfusion was associated with transfusion-associated circulatory overload after controlling for other covariates. Additional research is needed to examine the benefit of reduced erythrocyte or plasma exposure in patients at high risk for transfusion-associated circulatory overload.

Red blood cell components: Meeting the quantitative and qualitative transfusion needs

Red blood cell (RBC) transfusion is a very common therapeutic intervention. However, because of multiple recent studies improving our understanding of appropriate transfusion scenarios, the total number of RBC units transfused per year is actually decreasing in the developed world and there are no longer major shortages of RBC products for general use. Nonetheless, there are an increasing number of "special" uses, which can put strains on the blood supply for particular types of products; these may produce shortages of specific types of RBCs or require collections targeting certain types of donors. This review will focus on several broad topics, including providing some examples of "special" settings that require, or could require, special types of RBC products.

Trends in red blood cell transfusion and 30-day mortality among hospitalized patients

BACKGROUND

Blood conservation strategies have been shown to be effective in decreasing red blood cell (RBC) utilization in specific patient groups. However, few data exist describing the extent of RBC transfusion reduction or their impact on transfusion practice and mortality in a diverse inpatient population.

STUDY DESIGN AND METHODS

We conducted a retrospective cohort study using comprehensive electronic medical record data from 21 medical facilities in Kaiser Permanente Northern California. We examined unadjusted and risk-adjusted RBC transfusion and 30-day mortality coincident with implementation of RBC conservation strategies.

RESULTS

The inpatient study cohort included 391,958 patients who experienced 685,753 hospitalizations. From 2009 to 2013, the incidence of RBC transfusion decreased from 14.0% to 10.8% of hospitalizations; this change coincided with a decline in pretransfusion hemoglobin (Hb) levels from 8.1 to 7.6 g/dL. Decreased RBC utilization affected broad groups of admission diagnoses and was most pronounced in patients with a nadir Hb level between 8 and 9 g/dL (n = 73,057; 50.8% to 19.3%). During the study period, the standard deviation of risk-adjusted RBC transfusion incidence across hospitals decreased by 44% (p < 0.001). Thirty-day mortality did not change significantly with declines in RBC utilization in patient groups previously studied in clinical trials nor in other subgroups.

CONCLUSIONS

After the implementation of blood conservation strategies, RBC transfusion incidence and pretransfusion Hb levels decreased broadly across medical and surgical patients. Variation in RBC transfusion incidence across hospitals decreased from 2010 to 2013. Consistent with clinical trial data, more restrictive transfusion practice did not appear to impact 30-day mortality.