ABSTRACT

Transfusions of red blood cells (RBCs) remain controversial in patients with septic shock but, recommended in septic shock and the majority of these patients receive RBCs transfusion in the intensive care unit (ICU). However, benefit and harm of RBCs have not been clearly established in this group of patients yet. The purpose of this short communication is to draw attention to new clinical studies performed in patients with septic shock. Holst and colleagues now provide definitive evidence that a restrictive approach to blood transfusion not only reduced blood use by half but also did not cause harm. In this multicenter, parallel-group trial, they randomly assigned patients in the intensive care unit (ICU) who had septic shock and a hemoglobin concentration of 9 g/dL per deciliter or less to receive 1 unit of leuko-reduced red cells when the hemoglobin level was 7 g/dL or less (lower threshold) or when the level was 9 g/dL or less (higher threshold) during the ICU stay. The primary outcome measure was death by 90 days after randomization. Holst et al. conclude that there are no significant differences in terms of mortality and rates of ischemic events and use of life support when considering different hemoglobin thresholds in patients with septic shock. Much like the results of the Transfusion Requirements in Septic Shock (TRISS) trial by Holst et al., approximately 50% less blood was administered in the restrictive strategy group than in the liberal-strategy group. In two recently published multicenter RCTs, “Protocolized Care for Early Septic Shock (ProCESS)” and the “Australasian Resuscitation in Sepsis Evaluation (ARISE)” trials also evaluated the results of early goal-directed therapy (EGDT) versus protocol-based standard therapy or usual care in patients with septic shock. These trials included a transfusion threshold of a hematocrit of 30% when central venous oxygen saturations remained below 70% in the EGDT group. In contrast to the triggers, in the EGDT group, protocol-based standard therapy group and usual-care group, hemoglobin level was less than 7.5 g per deciliter recommended packed red-cell transfusion. The clinical protocols of the two trials included a transfusion threshold of a hematocrit of 30% when central venous oxygen saturations remained below 70% in EGDT group. There were no significant differences in 90-day mortality, 1-year mortality, or the need for organ support between groups despite the fact that twice the number of patients in the goal-directed groups as in the usual-care groups were administered blood. At least, these four trials confirm that there is no difference in outcomes between restrictive vs. liberal transfusion targets. It implies that hemoglobin is not a discriminating factor for survival in septic shock.

Keywords: Protocoled therapy, septic shock, transfusion threshold, early goal directed therapy