We classified the study by Chatterjee et al as “Less Is More” because the summary data from observational studies indicate no obvious benefit, and probable harm, associated with blood transfusions in critically ill patients with acute myocardial infarction and hematocrits of less than 27% to 30% compared with lower transfusion thresholds. In keeping with the ethic of nonmaleficence, until high-quality randomized trials are performed to test the efficacy of transfusions in the setting of acute myocardial infarction, physicians should transfuse patients only when there is sufficient clinical reason, supported by evidence. Merely having a hematocrit below 27% or 30% should not be sufficient to justify transfusion. In this case, it seems likely that less transfusing may be associated with better outcomes. As Drs Carson and Hébert indicate in their Invited Commentary, randomized trials will be published soon on this topic, so stay tuned.
O’Malley PG. Less Transfusion Is Likely More in Acute Myocardial InfarctionComment on “Association of Blood Transfusion With Increased Mortality in Myocardial Infarction: A Meta-analysis and Diversity-Adjusted Study Sequential Analysis”. JAMA Intern Med. 2013;173(2):141. doi:10.1001/jamainternmed.2013.1786