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(BQ) Part 4 book Millers textbook has contents: Patient blood management - Autologous blood procurement, recombinant factor viia therapy, and blood utilization, anesthesia and treatment of chronic pain, palliative medicine, anesthesia for thoracic surgery, anesthesia for cardiac surgical procedures
Chapter 63 Patient Blood Management: Autologous Blood Procurement, Recombinant Factor VIIa Therapy, and Blood Utilization LAWRENCE T GOODNOUGH • TERRI G MONK Key Points • The two primary reasons for employing autologous transfusion are avoidance of complications associated with allogeneic transfusion and conservation of blood resources • The three types of autologous blood transfusion are preoperative autologous donation (PAD), acute normovolemic hemodilution (ANH), and intraoperative and postoperative blood recovery (salvage) • PAD became accepted as a standard practice in certain elective surgical settings such as total joint replacement surgery, so that by 1992 more than 6% of the blood transfused in the United States was autologous Subsequently, substantial improvements in blood safety were accompanied by a decline in PAD as well as an interest in ANH as an alternative, lower-cost strategy The criteria for autologous donors are different from those for allogeneic donors Transfusion service policies, implemented under the auspices of hospital transfusion committees, differ regarding collection and use of autologous blood with positive viral markers It is common practice to exclude autologous blood reactive for hepatitis B surface antigen and hepatitis C and human immunodeficiency viruses because of patients’ safety concerns related to wrong blood unit transfused to wrong patient (mistransfusion) Contraindications to autologous blood donation include evidence of infection and risk of bacteremia, scheduled surgery for correction of aortic stenosis, and unstable angina • The costs associated with PAD are higher than those associated with the collection of allogeneic blood • ANH is the removal of whole blood from a patient while restoring the circulating blood volume with an acellular fluid shortly before an anticipated significant surgical blood loss The chief benefit of ANH is the reduction of red blood cell losses when whole blood is shed perioperatively at the lower hematocrit levels associated with ANH • The term intraoperative blood collection or recovery describes the technique of collecting and reinfusing blood lost by a patient during surgery The oxygen transport properties of recovered red blood cells are equivalent to those of stored allogeneic red blood cells The survival of recovered blood cells appears to be at least comparable to that of transfused allogeneic red blood cells • Postoperative blood collection denotes the recovery of blood from surgical drains followed by reinfusion, with or without processing Postoperative autologous blood salvage and reinfusion are practiced widely but not uniformly • Recombinant factor VIIa (rfVIIa) has been approved for treatment of bleeding in patients with hemophilia and inhibitors to factors VIII or IX Pharmacologic doses of rfVIIa enhance the thrombin generation on activated platelets and therefore may also be of benefit in providing hemostasis in other situations such as those characterized by consumptive coagulopathies or platelet conditions with impaired thrombin generation • Level I evidence and guidelines support restrictive transfusion practices However, no one hemoglobin level should be used as a transfusion trigger, and transfusion decisions should be made for individual patients (see also Chapter 61) • Bloodless medicine and surgery use a multidisciplinary team approach that incorporates anemia management, controlled hemostasis, autologous blood procurement, and pharmacologic alternatives to blood transfusion 1881 1882 PART IV: Anesthesia Management Blood management has been defined as “the appropriate use of blood and blood components, with a goal of minimizing their use.”1 This goal has been motivated historically by (1) known blood risks, (2) unknown blood risks, (3) preservation of the national blood inventory, and (4) constraints from escalating costs Known risks of blood include transmissible infectious disease, transfusion reactions, and potential effects of immunomodulation (e.g., postoperative infection or tumor progression) Unknown risks include emerging pathogens transmissible by blood (e.g., new variant Creutzfeldt-Jakob disease and West Nile virus).2,3 Several studies have linked allogeneic blood transfusions with unfavorable outcomes, including increased risk of mortality and various morbidities.4 Blood management has been of the 10 key advances in transfusion medicine since the 1960s.5 Patient blood management encompasses an evidence-based medical and surgical approach that is multidisciplinary (transfusion medicine specialists, surgeons, anesthesiologists, and critical care specialists) and multiprofessional (physicians, nurses, pump technologists, and pharmacists).6 Preventive strategies are emphasized: to identify, evaluate, and manage anemia7-9 (e.g., pharmacologic therapy10 and reduced iatrogenic blood losses from diagnostic testing)11; to optimize hemostasis (e.g., pharmacologic therapy12 and point-ofcare testing13); and to establish decision thresholds (e.g., guidelines) for the appropriate administration of blood therapy.14,15 In the United States, The Joint Commission developed patient blood management performance measures and submitted these to the National Quality Forum for endorsement The National Quality Forum did not endorse these submitted performance measures because of a lack of data on the outcomes proposed; as a result, these measures currently not carry consequences if not met Because these performance measures were process based rather than outcomes based, data on proposed outcomes are difficult to retrieve The Joint Commission has placed these performance measures in their Topic Library, where they are to be used as additional patient safety activities and/or quality improvement projects by provider institutions as accreditation goals.15 The principles of these performance indicators are summarized in Box 63-1 AUTOLOGOUS BLOOD PROCUREMENT The three types of autologous blood transfusion are preoperative autologous donation (PAD), acute normovolemic hemodilution (ANH), and intraoperative and postoperative blood recovery (blood salvage) The advantages, disadvantages, applications, and complications vary with the techniques used The two primary reasons for employing autologous transfusion are avoidance of complications associated with allogeneic transfusion and conservation of the national blood inventory Patients with rare blood phenotypes or alloantibodies can also benefit from autologous transfusion because compatible allogeneic blood may not always be available.16 Potential complications of BOX 63-1 Patient Blood Management TJC Performance Measures Preoperative Anemia Screening Preoperative Blood Type and Antibody Screen (Blood Compatibility Testing) Transfusion Consent Blood Administration RBC Transfusion Indication Plasma Transfusion Indication Platelet Transfusion Indication Principles A Formulate a plan of proactive management for avoiding and controlling blood loss tailored to the clinical management of individual patients, including anticipated procedures. B Employ a multidisciplinary treatment approach to blood management using a combination of interventions (e.g., pharmacologic, therapy, point-of-care testing) C Promptly investigate and treat anemia D Exercising clinical judgment, be prepared to modify routine practices (e.g., transfusion triggers) when appropriate E Restrict blood drawing for unnecessary laboratory tests F Decrease or avoid the perioperative use of anticoagulants and antiplatelet agents RBC, Red blood cell; TJC, The Joint Commission allogeneic transfusion that can be eliminated or minimized when autologous blood is administered include acute and delayed hemolytic reactions, alloimmunization, allergic and febrile reactions, and transfusion-transmitted infectious diseases Intraoperative blood recovery may be the only option for providing a sufficient volume of compatible blood when severe, rapid blood loss occurs ANH provides the only practical source of fresh whole blood The role of autologous blood procurement in surgery is evolving, based on improved blood safety, increased blood costs, and emerging pharmacologic alternatives to blood transfusion.17-19 PAD became accepted as a standard practice in certain elective surgical settings such as total joint replacement surgery; by 1992 more than 6% of the blood transfused in the United States was autologous.20 Subsequently, substantial improvements in blood safety were accompanied by a decline in PAD, as well as an interest in ANH as an alternative strategy.21 Nevertheless, public perception of blood safety and the reluctance to accept allogeneic blood transfusion in the elective transfusion setting,22 along with possible future blood inventory shortages and the potential for new, emerging blood pathogens, continue to give autologous blood procurement strategies an important role in the surgical arena PREOPERATIVE BLOOD DONATION Patient Selection The criteria for autologous donors are not as stringent as are those for allogeneic donors The AABB (formerly, Chapter 63: Patient Blood Management the American Association of Blood Banks) standards for blood banks and transfusion services require that the donor patient’s hemoglobin be no less than 11 g/dL or the hematocrit be no less than 33% before each donation.23 No age or weight limits exist, and patients may donate 10.5 mL/kg, in addition to testing samples Donations may be scheduled more than once a week, but the last donation should occur no less than 72 hours before surgery, to allow time for restoration of intravascular volume and for transport and testing of the donated blood Transfusion service policies, implemented under the auspices of hospital transfusion committees, differ regarding collection and use of autologous blood with positive viral markers Some hospitals exclude use of autologous blood reactive for hepatitis B surface antigen, hepatitis C virus, or human immunodeficiency virus (HIV) because of concerns for patients’ safety related to a wrong blood unit transfused to the wrong patient (mistransfusion) Other hospitals accept and transfuse autologous blood with any positive viral markers because denying patients infected with HIV the opportunity to receive their own blood may have implications related to the Americans with Disabilities Act.24 Candidates for preoperative blood collection are patients scheduled for elective surgical procedures in which blood transfusion is likely The most common surgical procedures for which autologous blood is predonated are total joint replacements.25 For procedures that are unlikely to require transfusion (i.e., a maximal surgical blood ordering schedule [MSBOS] suggests that crossmatched blood should not be ordered),26 the use of preoperative blood collection is not recommended Autologous blood should not be collected for procedures that seldom (