Author: Christian S. Guay, MD
International Anesthesia Research Society
The Daily Dose April 2023
The COVID-19 pandemic brought to light many deficiencies in our medical systems, notably how we manage the body’s liquid organ: blood. In this update from the Society for the Advancement of Blood Management (SABM), “Patient Blood Management is a New Standard of Care to Improve Patient Outcomes: Current Research and Evidence-Based Guidelines,” held Friday, April 14, at the IARS 2023 Annual Meeting, three experts introduced attendees to the concept of blood health and how we can leverage perioperative patient blood management to reduce risk, improve outcomes and save costs.
Susan Goobie, MD, FRCPC, Associate Professor of Anaesthesiology at Harvard Medical School and Boston Children’s Hospital, opened the session with an introduction to blood health. Analogous to heart health and gut health, blood health is interconnected with all other body systems and is an important component of patient-centered care. Suboptimal blood health can manifest as anemia, coagulopathy, bleeding and thrombosis. Blood transfusions, essentially liquid organ transplants, can be lifesaving but also carry risk and feature among the most important healthcare-related overuse issues.
Patient blood management (PBM) is a patient-centered, systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient’s own blood. This approach is all about doing more with less, which allows us to close the gap between supply and demand. The WHO has stated that almost every individual can benefit from PBM during their lifetime, and multiple expert-consensus and evidence-based guidelines have been published. Multimodal blood conservation strategies are applicable across all patient groups and have been shown to reduce the rate of red blood cell transfusions as well as complications, such as infections, renal failure and thromboembolic events. Dr. Goobie specifically recommended referring to the guidelines published by the national blood authority of Australia (www.blood.gov.au).
The discussion then focused in on anemia with Nicole Guinn, MD, Associate Professor of Anesthesiology at Duke University. Anemia easily features among the most common comorbidities of our patients presenting for surgery, with estimates around 30% for both cardiac and noncardiac surgery. This is not a benign comorbidity – postoperative mortality is higher for anemic patients, and they are at increased risk of stroke and acute kidney injury (AKI). Interestingly, transfusion is even more strongly associated with postoperative death, AKI and stroke than anemia alone. Thankfully, treating anemia preoperatively improves outcomes. The first step is identifying the etiology. Iron deficiency is by far the most common offender, followed by anemia or chronic disease, then folate and B12 deficiency. Once the diagnosis is confirmed, timely treatment is essential to allow for preoperative erythropoiesis.
What if blood transfusions simply aren’t an option… is “bloodless surgery” even possible? Steven Frank, MD, a professor in the Department of Anesthesiology and Critical Care and Director of the Center for Bloodless Medicine and Surgery at Johns Hopkins, explained that this was in fact the case for over a century, from the advent of ether anesthesia to the creation of the first blood banks in the 1940s. Today, 90% of bloodless surgeries are the result of patients’ personal or religious beliefs, with alloantibodies and blood unavailability accounting for the rest. Jehovah’s Witnesses typically refuse transfusions of red blood cells, fresh frozen plasma and platelets due to a literal interpretation of passages in the Bible. However, most will accept hemoglobin-based oxygen carriers, albumin and clotting factor concentrates. Treating preoperative anemia is a cornerstone of bloodless surgery. Furthermore, it’s possible to derive a target preoperative hemoglobin goal based on a patient’s mass and estimated blood loss. In general, larger patients will have lower preoperative hemoglobin goals for any given surgery given their higher circulating volume. Once preoperative blood health is optimized, intraoperative management should focus on simply keeping the blood in the patient! This means appropriately discontinuing anticoagulants, good communication with the surgical team, autologous cell salvage, correcting hypothermia, intraoperative normovolemic hemodilution, controlled hypotension, antifibrinolytics and decreasing blood draw volume and frequency.
In conclusion, the session highlighted the crucial role of blood health in patient-centered care and the potential of patient blood management to improve outcomes while reducing risks and costs.