Red blood cell transfusion triggers in acute leukemia: a randomized pilot study

Abstract

BACKGROUND Red blood cell (RBC) transfusion thresholds have yet to be examined in large randomized trials in hematologic malignancies. This pilot study in acute leukemia uses a restrictive compared to a liberal transfusion strategy. STUDY DESIGN AND METHODS A randomized (2:1) study was conducted of restrictive (LOW) hemoglobin (Hb) trigger (7 g/dL) compared to higher (HIGH) Hb trigger (8 g/dL). The primary outcome was feasibility of conducting a larger trial. The four requirements for success required that more than 50% of the eligible patients could be consented, more than 75% of the patients randomized to the LOW arm tolerated the transfusion trigger, fewer than 15% of patients crossed over from the LOW arm to the HIGH arm, and no indication for the need to pause the study for safety concerns. Secondary outcomes included fatigue, bleeding, and RBCs and platelets transfused. RESULTS Ninety patients were consented and randomly assigned to LOW to HIGH. The four criteria for the primary objective of feasibility were met. When the number of units transfused was compared, adjusting for baseline Hb, the LOW arm was transfused on average 8.0 (95% confidence interval [CI], 6.9–9.1) units/patient while the HIGH arm received 11.7 (95% CI, 10.1–13.2) units (p = 0.0003). There was no significant difference in bleeding events or neutropenic fevers between study arms. CONCLUSION This study establishes feasibility for trial of Hb thresholds in leukemia through demonstration of success in all primary outcome metrics and a favorable safety profile. This population requires further study to evaluate the equivalence of liberal and restrictive transfusion thresholds in this unique clinical setting.

Impact of red blood cell transfusion strategies in haemato‐oncological patients: a systematic review and meta‐analysis

“…Incidence of bleeding was reported by four studies (Jansen et al , ; Webert et al , ; Berger et al , ; DeZern et al , ). No differences in the occurrence of any bleeding or clinically significant bleeding were found between the liberal and restrictive RBC transfusion group in a study of 60 patients (120 g/l vs. 80 g/l), RR 1·05 (95% CI 0·87–1·26) and RR 0·94 (95% CI 0·69–1·27) (Webert et al , ).…”

“…Tables and provide information on the bias risk assessment. Two RCTs were classified as ‘low risk of bias’ (Webert et al , ; DeZern et al , ). A lack of blinding in the RCT reported by DeZern et al () was allowed as blinding in transfusion studies is almost impossible.…”

“…Two RCTs were classified as ‘low risk of bias’ (Webert et al , ; DeZern et al , ). A lack of blinding in the RCT reported by DeZern et al () was allowed as blinding in transfusion studies is almost impossible. Five ‘low risk of bias’ observational studies were included (Jansen et al , ; Paananen et al , ; Berger et al , ; Lightdale et al , ; Hoeg et al , ) and one was excluded because of a high risk of bias (Bishop, ).…”

Audit of red blood cell transfusion in patients with acute leukemia at a tertiary care university hospital

“…The transfusion criteria used in AL patients in this audit were mostly similar to those used for the general population. Although Hb transfusion thresholds in hematologic malignancy patients have not been universally agreed upon, two small randomized clinical trials have evaluated the use of a restrictive Hb threshold (7 g/dL) in AL patients and found that it led to noninferior outcomes more than did a higher threshold (8–9 g/dL) . Larger trials are needed to standardize restrictive transfusion thresholds in AL patients according to the clinical scenario.…”

Red cell transfusion thresholds in haematopoietic stem cell transplantation

“…In the second trial, DeZern et al . randomized patients receiving induction therapy to a red cell transfusion threshold of 70 g/l or 80 g/l . Of note, the liberal transfusion in this pilot trial used the same transfusion threshold as the restrictive transfusion strategy in the previous trial.…”