A patient blood management program safely reduced the need for blood transfusions among patients undergoing common orthopaedic surgeries, according to a study published in Anesthesiology.
“A growing body of literature shows reducing blood use in surgery reduces risks to patients while also lowering costs,” said lead author Steven M. Frank, MD, Johns Hopkins Health System Blood Management Program, Baltimore, Maryland. “However, there is a persistent impression that orthopaedic surgery patients require a higher haemoglobin transfusion threshold than other patient populations.”
American Association of Blood Banks (AABB) guidelines call for most patients to be given a blood transfusion when their haemoglobin level drops to 7 g/dL. However, for orthopaedic and cardiac surgery patients, the guidelines call for giving a blood transfusion when their level drops to 8 g/dL.
“It may seem like a small difference, but before our blood management program was implemented, one third of blood used in our hospital was transfused at levels between 7 and 8 g/dL, so a lot of blood was given in that intermediate zone,” said Dr. Frank. “A substantial number of transfusions could potentially be avoided by lowering the threshold to 7 g/dL.”
For the study, the researchers evaluated blood transfusion practices and clinical outcomes in all adult orthopaedic patients over a 4-year period, which covered the time in which the hospital implemented its blood management program. The study included 1,507 patients before the program was implemented and 2,402 after implementation.
The blood management program consisted of 10 strategies to reduce transfusions, including only administering a single unit of blood unless the patient was actively haemorrhaging, administering tranexamic acid during surgery to reduce bleeding, maintaining normal body temperature during surgery to reduce bleeding, adding pop-up alerts in patient electronic medical records to notify clinicians when the amount of blood ordered for a transfusion was above recommended levels, guideline compliance audits with provider feedback, smaller tubes to reduce blood loss from lab tests, and using newer surgical techniques to reduce bleeding.
After the blood management program was implemented, the percentage of patients who received blood transfusions decreased from 16.1% to 9.4%. The average hemoglobin threshold used to trigger a transfusion decreased from 7.8 g/dL to 6.8 g/dL. Overall blood use during transfusions decreased by 32.5%.
In hospital-acquired complications fell from 1.3% to 0.54%, and 30-day readmissions fell from 9% to 5.8%. Improved outcomes were primarily recognized in patients aged 65 years or older.
“We found that in orthopaedic patients, even with a lower haemoglobin trigger of 7 g/dL for blood transfusions, patients did as well or better than they did with a higher haemoglobin trigger level,” said Dr. Frank. “This is the first study to show that for most orthopaedic patients — even elderly patients — a haemoglobin level of 7 g/dL appears to be safe.”
He noted that while the study does suggest that most orthopaedic patients could be transfused at a haemoglobin level of 7 g/dL instead of 8 g/dL, this was not a randomised clinical trial.
“A trial formally assessing this lower haemoglobin trigger should be conducted before guidelines are changed to recommend a level of 7 g/dL for all orthopaedic patients,” he said. “Furthermore, we treat the whole patient, not just their lab values, so signs and symptoms of anaemia should also be considered.”