Current guidelines for the management of upper gastrointestinal (GI) bleeding recommend a transfusion threshold hemoglobin (hgb) level of 7 g/dL. However, evidence for a restrictive transfusion strategy in acute GI bleeding is lacking. Càndid Villanueva and investigators in Barcelona, Spain, performed a randomized clinical trial to assess whether a restrictive versus liberal blood transfusion strategy was safer for patients with acute GI hemorrhage. Their results were published in the January 3, 2013, issue of The New England Journal of Medicine.

From 2003 to 2009, a total of 889 adult patients with acute, but not massive upper GI hemorrhage were randomized to either a restrictive (hgb <7 g/dL) or liberal (hgb <9 g/dL) transfusion strategy threshold group. Block randomization was performed and the analysis proceeded according to the intention-to-treat principle. The study was not blinded. The primary outcome was death from any cause within the first 45 days after bleeding. Secondary outcomes included complications and the rate of further bleeding. A Kaplan-Meier plot was constructed and a Cox proportional hazards model was used to compare the two groups with respect to the endpoints, controlling for baseline risk factors. 

Four hundred forty-four patients were randomized to the restrictive group and 445 were randomized to the liberal group. There was no statistically significant difference between the two groups in terms of baseline characteristics. Unadjusted mortality was statistically higher for the liberal group (9%) compared to the restrictive group (5%; P=0.02). The survival benefit for the restrictive group remained after adjustment for baseline risk factors for death (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.33 to 0.92).  The rate of further bleeding was lower in the restrictive group (10%) compared to the liberal group (16%; P=0.01), and effect that persisted after adjustment for baseline risk factors (HR 0.68; 95% CI, 0.47 to 0.98). The overall rate of complications was higher in the liberal group (48%) compared to the restrictive group (40%; P=0.02). Transfusion reactions and cardiac events occurred more commonly in the liberal group. The authors concluded that a restrictive strategy was associated with improved outcomes for patients with acute upper GI bleeding.

Based on the unadjusted control and experimental event rates, 24 patients would need to be treated with the restrictive strategy to save one life (absolute risk reduction, 4%; 95% CI, 0.6% to 7.5%). Strengths of this study include its randomized design and an appropriate statistical analysis. The results are not externally generalizable for patients with massive GI bleeding, and the use of a lower transfusion threshold in patients with significant cardiovascular disease is not supported by these data. Indeed, for patients with hypovolemia and shock secondary to massive GI hemorrhage, transfusion should not be withheld. Existing guidelines already endorse a restrictive strategy (hgb <7 g/dL); this work supports such an approach for most patients. 

Concise Critical Appraisal is a regular feature authored by SCCM member Samuel M. Galvagno Jr., DO, PhD. Each installment highlights journal articles most relevant to the critical care practitioner.