[Accepted low hemoglobin levels in the perioperative period. A questionnaire survey among Norwegian anesthesiologists].

Declining haemoglobin concentrations are accepted in order to avoid allogeneic blood transfusions in surgical patients. A questionnaire was sent to all members of the Norwegian Association of Anaesthesiologists addressing the question of safe blood levels of haemoglobin in different patient groups, and the different blood conservation techniques used in their hospital. 206 questionnaires (49%) were returned. Intraoperative and postoperative autotransfusions were the two most frequently used methods of saving blood. The survey demonstrates a wide diversity in the accepted lower haemoglobin levels, especially in children, and in spite of its limitations sheds light on Norwegian anaesthetists' routines as regards the indications for blood transfusion and blood conservation in the perioperative period.