Fig. 2
Flow diagram of the extracted data with the warnings for each category for the red blood cell (RBC) transfusion prescription (left) and the platelets transfusion prescription (right). HB: haemoglobin; ED: emergency department; CC: critical care; HO: haematology or oncology. Many transfusions were prescribed without haemoglobin or platelet results being available; prior to all point of care analysers being networked with PICS some RBC results would not have been available for extraction, or decisions to transfuse may have been based on blood gas results which were not extracted. In these cases prescribers would be presented with advice messages but warnings triggered by results would not be available. Password warnings for RBC transfusion (1) May 2012: a warning was shown when clinicians prescribed RBC for patients who had a haemoglobin ≥ 100 g/L. (2) May 2015: (in addition to the first warning): a further warning appeared in non-CC/HO patients if haemoglobin was ≥ 80 g/L and in CC if haemoglobin was ≥ 70 g/L in response to prescription of RBCs. (3) July 2016: (replacing the warning introduced in May 2015). A warning was triggered for all patients if haemoglobin was ≥ 70 g/L in all clinical locations. Warnings for platelet transfusions: (1) May 2015: a warning was shown when clinicians prescribed platelets if the platelet count was > 20 × 109/L in all locations. (2) July 2016: the limit was lowered so that the warning appeared if the platelet count was > 10 × 109/L