Making transfusion decisions in critical care

Abstract

Transfusion triggers and parameters to consider in the decision to transfuse depend on the setting. In cases of massive bleeding, transfusion decision is made on haemodynamic parameters, vital signs and when possible on bleeding volume estimation. In anaemic haemodynamically stable patients, haemoglobin remains the primary trigger for transfusion. In the less severe or in the youngest critically ill patients, transfusion for a haemoglobin threshold of 7 g/dl has been shown to be associated with higher survival in comparison with a haemoglobin threshold of 10 g/dl. This lower threshold of 7 g/dl appears to be also safe in patients with upper gastrointestinal bleeding. In patients with acute ischaemic heart disease, where anaemia may worsen myocardial ischaemia, pathophysiology and findings from large observational studies support the benefit of a higher haemoglobin threshold (between 9 and 10 g/dl). Elderly and cardiovascular patients should be monitored for cardiac tolerance of anaemia and transfused accordingly. In haematology–oncology patients and in neuro critically ill patients, the optimal strategy for red blood cell (RBC) transfusion remains unknown. Transfusion practices have shifted from liberal towards restrictive strategy, making the monitoring of anaemia tolerance an important element in the decision to transfuse. Substantial comorbidities and conditions that influence anaemia tolerance should be integrated into clinicians’ transfusion decision‐making process. Research evaluating the benefit to consider additional triggers in the decision to transfuse RBC in critically ill patients is warranted.