2018 Evidence Base of Patient Blood Management - Recommendations from the First International Consensus Conference, Frankfurt/Main, Germany

Introduction: The analysis of published clinical trial results is essential for the evidence base of patient blood management (PBM). In addition, an evidence-based way of developing guidelines and recommendation is indispensable for high quality patient-centred hemotherapy. The international Consensus Conference (ICC) was set up in order to develop evidence-based clinical and research recommendations for preoperative anemia, red blood cell (RBC) transfusion thresholds in adult patients and implementation of PBM programmes.

Methods: An international scientific committee (SC) defined 17 population-intervention-comparison-outcome (PICO) questions for the three topics preoperative anemia, red blood cell (RBC) transfusion thresholds in adult patients and implementation of PBM. From these 17 PICO questions, literature search was conducted in four biomedical databases. Several meta-analyses, forest plots, the GRADE methodology (= grading of recommendations, assessment, development and evaluation), GRADEpro, the open source online database for GRADE as well as the Evidence-to-Decision (EtD) framework were used in order to keep the development of recommendations as evidence-based and transparent as possible. Three expert panels (EP) consisting of clinicians, scientists, nurses, patient representatives and methodologists were established and used the methods described above in order to develop recommendations driven by published evidence.

Results: Out of more than 17,500 literature citations, data from 145 studies (63 randomised trials including more than 23,000 patients (pts.) & 82 observational studies including more than 4 million pts.) was incorporated into the final analysis. The expert panel for preoperative anemia developed 4 clinical and 3 research recommendations. A strong recommendation advocates for early detection and management of preoperative anemia before major elective surgery. For RBC transfusion thresholds, 4 clinical and 6 research recommendations came out of the process. Two strong clinical recommendations for PBC transfusion thresholds advocate a hemoglobin level (hb) of < 7 g/dL for critical ill, but clinical stable adult intensive care patients independent of septic shock and < 7.5 g/dL for adults undergoing cardiac surgery. For implementation of PBM programmes, 2 clinical and 3 research recommendations were defined. Research recommendations define open fields in PBM and try to initiate additional studies in order to answer still open questions.

Conclusion: This is the first ICC for PBM defining the evidence base for three clinically important hemotherapy topics. The relative paucity of strong evidence in current PBM literature underscores the ongoing struggle to a.) find internationally accepted definitions e.g. for anemia and b.) execute internationally planned meaningful multicentre trials in the still open fields of PBM. The clinical recommendations found here however should be considered and accepted in clinical practice.