TRANSFUSION REQUIREMENTS IN CRITICAL CARE - A PILOT-STUDY

Objective.-To evaluate the effects of a restrictive and a liberal red blood cell (RBC) transfusion strategy on mortality and morbidity in cr itically ill patients. Study Design.-Multicenter, prospective, randomi zed clinical trial. Patient Population.-Sixty-nine normovolemic critic ally ill patients admitted to one of five tertiary level intensive car e units with hemoglobin values less than 90 g/L within 72 hours of adm ission. Interventions.-Patients were randomly allocated to one of two RBC transfusion strategies. Hemoglobin values were maintained between 100 and 120 g/L in the liberal transfusion group and between 70 and 90 g/L in the restrictive group. Results.-Primary diagnosis and mean+/-S D age (58.6+/-15 vs 59.0+/-21 years) and Acute Physiology and Chronic Health Evaluation II score (20+/-6.2 vs 21 +/-7.2) were similar in the restrictive and liberal groups, respectively. Daily hemoglobin values averaged 90 g/L in the restrictive group vs 109 g/L in the liberal gr oup (P<.001). The restrictive group received 2.5 U per patient compare d with 4.8 U per patient in the liberal group. This represents a 48% r elative decrease (P<.001) in RBC units transfused per patient. The 30- day mortality rate was 24% in the restrictive group compared with 25% in the liberal group; the 95% confidence interval around the absolute difference was -19% to 21%. Similar observations were noted for intens ive care unit mortality (P=.76) and 120-day mortality (P>.99). In addi tion, survival analysis comparing time until death in both groups did not reveal any significant difference (P=.93) between groups. Organ dy sfunction scores were also similar (P=.44). Conclusion.-In this small randomized trial, neither mortality nor the development of organ dysfu nction was affected by the transfusion strategy, which suggests that a more restrictive approach to the transfusion of RBCs may be safe in c ritically ill patients. However, the study lacked power to detect smal l but clinically significant differences. Therefore, further investiga tions of RBC transfusion strategies are warranted.