Association Between Length of Storage of Transfused Packed RBC Units and Outcome of Surgical Critically Ill Adults: A Subgroup Analysis of the Age of Blood Evaluation Randomized Trial

 

by Lehr, Anab Rebecca; Hébert, Paul; Fergusson, Dean; Sabri, Elham; Lacroix, Jacques 

 

Critical Care Medicine: December 26, 2022. 

 

Objectives: The Age of Blood Evaluation (ABLE) study reported no clinical benefit in fresher compared with standard delivery RBC units (length of storage: 6.9 ± 4.1 vs 22.0 ± 8.4 d, respectively). Perioperative patients are often anemic, at risk of blood loss, and more exposed to RBC transfusions. We address the question whether fresh RBC units are safer than standard delivery RBC units in perioperative ICU patients.

Design: Subgroup analysis of surgical nontrauma adults enrolled in the ABLE randomized controlled trial.

Setting: ICUs.

Patients: Three hundred twenty surgical patients among the 2,510 ICU adults recruited in the ABLE study who had a request for a first RBC transfusion in the first week in ICU stay and an anticipated length of mechanical ventilation greater than or equal to 48 hours. We included perioperative patients but excluded elective cardiac surgery and trauma.

Interventions: Surgical participants were allocated to receive either RBC units stored less than or equal to 7 days or standard issue RBC.

MEASUREMENTS AND MAIN RESULTS: 

The primary outcome was 90-day all-cause mortality.

One hundred seventy-two perioperative patients were allocated to the fresh and 148 to the standard group. Baseline data were similar. The length of storage was 7.2 ± 6.4 in fresh and 20.6 ± 8.4 days in standard group (p < 0.0001). The 90-day mortality was 29.7% and 28.4%, respectively (absolute risk difference: 0.01; 95% CI –0.09 to 0.11; p = 0.803). No significant differences were observed for all secondary outcomes, including 6-month mortality, even after adjustment for age, country, and Acute Physiology and Chronic Health Evaluation score.

Conclusions: There was no evidence that fresh red cells improved outcomes as compared to standard issue red cells in critically ill surgical patients, consistent with other patients enrolled in the ABLE trial.

 

RBC Transfusion in Venovenous Extracorporeal Membrane Oxygenation: A Multicenter Cohort Study

 

Critical Care Medicine: February 2022 - Volume 50 - Issue 2 - p 224-234

 

 

OBJECTIVES: In the general critical care patient population, restrictive transfusion regimen of RBCs has been shown to be safe and is yet implemented worldwide. However, in patients on venovenous extracorporeal membrane oxygenation, guidelines suggest liberal thresholds, and a clear overview of RBC transfusion practice is lacking. This study aims to create an overview of RBC transfusion in venovenous extracorporeal membrane oxygenation.

DESIGN: Mixed method approach combining multicenter retrospective study and survey. SETTING: Sixteen ICUs worldwide.

PATIENTS: Patients receiving venovenous extracorporeal membrane oxygenation between January 2018 and July 2019.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: The primary outcome was the proportion receiving RBC, the amount of RBC units given daily and in total. Furthermore, the course of hemoglobin over time during extracorporeal membrane oxygenation was assessed. Demographics, extracorporeal membrane oxygenation characteristics, and patient outcome were collected. Two-hundred eight patients received venovenous extracorporeal membrane oxygenation, 63% male, with an age of 55 years (45–62 yr), mainly for acute respiratory distress syndrome. Extracorporeal membrane oxygenation duration was 9 days (5–14 d). Prior to extracorporeal membrane oxygenation, hemoglobin was 10.8 g/dL (8.9–13.0 g/dL), decreasing to 8.7 g/dL (7.7–9.8 g/dL) during extracorporeal membrane oxygenation. Nadir hemoglobin was lower on days when a transfusion was administered (8.1 g/dL [7.4–9.3 g/dL]). A vast majority of 88% patients received greater than or equal to 1 RBC transfusion, consisting of 1.6 U (1.3–2.3 U) on transfusion days. This high transfusion occurrence rate was also found in nonbleeding patients (81%). Patients with a liberal transfusion threshold (hemoglobin > 9 g/dL) received more RBC in total per transfusion day and extracorporeal membrane oxygenation day. No differences in survival, hemorrhagic and thrombotic complication rates were found between different transfusion thresholds. Also, 28-day mortality was equal in transfused and nontransfused patients.

CONCLUSIONS: Transfusion of RBC has a high occurrence rate in patients on venovenous extracorporeal membrane oxygenation, even in nonbleeding patients. There is a need for future studies to find optimal transfusion thresholds and triggers in patients on extracorporeal membrane oxygenation.

 

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

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

Chong, M et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 252–263

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.

Effect of Transfusion on Mortality and Other Adverse Events Among Critically Ill Septic Patients: An Observational Study Using a Marginal Structural Cox Model

Effect of Transfusion on Mortality and Other Adverse Events Among Critically Ill Septic Patients: An Observational Study Using a Marginal Structural Cox Model

Dupuis, C et al
Critical Care Medicine: December 2017 - Volume 45 - Issue 12 - p 1972–1980

Objectives: RBC transfusion is often required in patients with sepsis. However, adverse events have been associated with RBC transfusion, raising safety concerns. A randomized controlled trial validated the 7 g/dL threshold, but previously transfused patients were excluded. Cohort studies led to conflicting results and did not handle time-dependent covariates and history of treatment. Additional data are thus warranted to guide patient’s management. Design: To estimate the effect of one or more RBC within 1 day on three major outcomes (mortality, ICU-acquired infections, and severe hypoxemia) at day 30, we used marginal structural models. A trajectory modeling, based on hematocrit evolution pattern, allowed identification of subgroups. Secondary analyses were performed into each of them. Setting: A prospective French multicenter database. Patients: Patients with sepsis at admission. Patients with hemorrhagic shock at admission were excluded. Interventions: None. Measurements and Main Results: Overall, in our cohort of 6,016 patients, RBC transfusion was not associated with death (hazard ratio, 1.07; 95% CI, 0.88–1.30; p = 0.52). However, RBC transfusion was associated with increased occurrence of ICU-acquired infections (hazard ratio, 2.77; 95% CI, 2.33–3.28; p < 0.01) and of severe hypoxemia (hazard ratio, 1.29; 95% CI, 1.14–1.47; p < 0.01). A protective effect from death by the transfusion was found in the subgroup with the lowest hematocrit level (26 [interquartile range, 24–28]) (hazard ratio, 0.72; 95% CI, 0.55–0.95; p = 0.02). Conclusions: RBC transfusion did not affect overall mortality in critically ill patients with sepsis. Increased occurrence rate of ICU-acquired infection and severe hypoxemia are expected outcomes from RBC transfusion that need to be weighted with its benefits in selected patients.

Should All Massively Transfused Patients Be Treated Equally? An Analysis of Massive Transfusion Ratios in the Nontrauma Setting

Should All Massively Transfused Patients Be Treated Equally? An Analysis of Massive Transfusion Ratios in the Nontrauma Setting

Etchill, E et al
Critical Care Medicine: August 2017 - Volume 45 - Issue 8 - Issue 8 - p 1311–1316

Objectives: Although balanced resuscitation has become integrated into massive transfusion practice, there is a paucity of evidence supporting the delivery of high ratios of plasma and platelet to RBCs in the nontrauma setting. This study investigated the administration of blood component ratios in the massively transfused nontrauma demographic. 
Design: Retrospective analysis of a prospective, observational cohort of massively bleeding patients. Setting: Surgical and critically ill patients at a tertiary medical center between 2011 and 2015. Patients: Massively transfused nontrauma patients. Interventions: Patients receiving plasma, platelet, and RBC transfusions were categorized into high and low ratio groups and analyzed for differences in characteristics and clinical outcomes. Measurements and Main Results: The primary outcome was 30-day mortality. Secondary outcomes included 48-hour mortality, hospital length of stay, ICU length of stay, and ventilator-free days. Among 601 massively transfused nontrauma patients, cardiothoracic surgery and gastrointestinal or hepato-pancreatico-biliary bleeds were the most common indications for massive transfusion. Higher fresh frozen plasma ratios (> 1:2) were not associated with increased 30-day mortality. A high platelets-to-packed RBCs ratio (> 1:2) was associated with decreased 48-hour mortality (10.5% vs 19.3%; p = 0.032), but not 30-day mortality. Fresh frozen plasma-to-packed RBCs and platelets-to-packed RBCs ratios were not associated with 30-day mortality hazard ratios after controlling for baseline characteristics and disease severity. 
Conclusions: The benefits of higher ratios of fresh frozen plasma-to-packed RBCs and platelets-to-packed RBCs described in trials of trauma patients were not observed in this analysis of a nontrauma, massively transfused population. These data suggest that greater than 1:2 ratio transfusion in the setting of massive hemorrhage may not be appropriate for all patients, and that further research to guide appropriate resuscitation strategies in nontrauma patients is warranted.

Liberal Versus Restrictive Transfusion Strategy in Critically Ill Oncologic Patients: The Transfusion Requirements in Critically Ill Oncologic Patients Randomized Controlled Trial

Liberal Versus Restrictive Transfusion Strategy in Critically Ill Oncologic Patients: The Transfusion Requirements in Critically Ill Oncologic Patients Randomized Controlled Trial

Bergamin, F S et al
Critical Care Medicine: May 2017 - Volume 45 - Issue 5 - p 766–773

Objective: To assess whether a restrictive strategy of RBC transfusion reduces 28-day mortality when compared with a liberal strategy in cancer patients with septic shock. Design: Single center, randomized, double-blind controlled trial. Setting: Teaching hospital. Patients: Adult cancer patients with septic shock in the first 6 hours of ICU admission. Interventions: Patients were randomized to the liberal (hemoglobin threshold, < 9 g/dL) or to the restrictive strategy (hemoglobin threshold, < 7 g/dL) of RBC transfusion during ICU stay. Measurements and Main Results: Patients were randomized to the liberal (n = 149) or to the restrictive transfusion strategy (n = 151) group. Patients in the liberal group received more RBC units than patients in the restrictive group (1 [0–3] vs 0 [0–2] unit; p < 0.001). At 28 days after randomization, mortality rate in the liberal group (primary endpoint of the study) was 45% (67 patients) versus 56% (84 patients) in the restrictive group (hazard ratio, 0.74; 95% CI, 0.53–1.04; p = 0.08) with no differences in ICU and hospital length of stay. At 90 days after randomization, mortality rate in the liberal group was lower (59% vs 70%) than in the restrictive group (hazard ratio, 0.72; 95% CI, 0.53–0.97; p = 0.03). Conclusions: We observed a survival trend favoring a liberal transfusion strategy in patients with septic shock when compared with the restrictive strategy. These results went in the opposite direction of the a priori hypothesis and of other trials in the field and need to be confirmed.