Sanne de Bruin

57 Transfusion practice in the bleeding critically ill; an international online survey – The TRACE-2 Survey Background Transfusion is common practice in the intensive care unit (ICU), with about 40-50% of the critically ill being transfused during ICU admission 1 . While the transfusion of blood products can enhance the life expectancy of critically ill patients 2 , there has been grow- ing awareness about the possible side effects of transfusion 2,3 . Blood products contain inflammatory components including reactive oxygen species, foreign antigens and var- ious pro-inflammatory micro-particles 4–7 . These inflammatory components may induce harmful transfusion reactions, such as allergic reactions, hemolysis and acute lung injury, especially in the critically ill 8,9 . This explains why restrictive transfusion strategies in the non-bleeding critically ill are safe and decrease exposure to RBC transfusion as compared to liberal transfusion practices 10–14 . There are no data available on transfusion practices specifically for bleeding critically ill patients. The majority of transfusion studies in bleeding patients were conducted in trauma patients. In general, trauma patients are a relatively healthy population with limited comorbidities. Therefore, this evidence might not be directly generalizable to bleeding, non-trauma, critically ill patients. Transfusion practice in bleeding patients is challenging, with multiple causes including coagulopathy, thrombocytopenia and can occur as a consequence of surgery. Coagulopathy can also be a consequence of bleeding. To control bleeding, patients often receive different types of blood products, many of which are delivered simultaneously. This survey aims to assess the practice of caregivers towards transfusion practices in the bleeding critically ill patient, including transfusion thresholds, choices of blood products and diagnostic tests. We hypothesized that in this patient population a large heterogeneity exists between and within different subpopulations. Methods Survey A questionnaire was distributed to physicians working in adult ICUs worldwide using an online platform (SurveyMonkey, Portland, OR, USA). This questionnaire was a follow-up of the first TRACE survey, which focused on non-bleeding critically ill patients 15 . This study was endorsed by the European Society of Intensive Care Medicine (ESICM) and by several national intensive care societies (Additional file 2). 3