|Year : 2021 | Volume
| Issue : 1 | Page : 3-5
Moving to the next level of precision medicine with patient blood management
Professor and Head, Department of Immunohematology and Blood Transfusion, Kasturba Medical College, Manipal; Manipal Academy of Higher Education, Manipal, Karnataka, India
|Date of Submission||21-Apr-2021|
|Date of Decision||30-Apr-2021|
|Date of Acceptance||04-May-2021|
|Date of Web Publication||29-May-2021|
Dr. Shamee Shastry
Professor and Head, Department of Immunohematology and Blood Transfusion, Kasturba Medical College, Manipal; Manipal Academy of Higher Education, Manipal, Karnataka
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Shastry S. Moving to the next level of precision medicine with patient blood management
. Glob J Transfus Med 2021;6:3-5
The discovery of ABO grouping with the use of group-specific blood heralded the beginning of what is now called “precision medicine” Over time, transfusion medicine has become increasingly personalized with compatibility testing, minor blood groups, platelets, and human leukocyte antigen (HLA) matching in different patient groups. Although the concept had been there for many years, the term “precision medicine” was introduced to the healthcare system recently. The National Research Council (US) Committee on A Framework for Developing a New Taxonomy of Disease, defined precision medicine as “The tailoring of medical treatment to the individual characteristics of each patient.” They proposed to classify the patients into subpopulations based on their susceptibility and response to a disease. Patient blood management (PBM) is one such strategy that is taking the field of transfusion medicine toward a higher level of precision medicine. HLA typing before solid organ or peripheral blood stem cell transplantation, selective removal of lipids from a patient with Familial hypercholesteremia, use of O negative Red cells suspended in AB plasma for neonatal exchange transfusion, preparation of cryoprotectants for freezing autologous cells using patients own plasma are examples for Precision Medicine. However, PBM is probably the most specific and hopefully one that is going to be applied widely in future.
| Patient Blood Management-A prototype of Precision Medicine|| |
PBM is an evidence-based multidisciplinary approach, which involves pharmacologic, medical, and surgical modalities to manage anemia, optimize hemostasis, and minimize blood loss in a patient-specific manner. The various steps of implementation of PBM in a hospital setting have been addressed very well in the 20th edition of the Technical Manual by AABB. The major guidelines on red blood cell and platelet transfusions put forward recommendations based on the “trigger,” the hemoglobin level, or the platelet count. However, the basic principle of PBM is “one size does not fit all” and deploys subpopulation-specific strategies. Meybohm et al. have provided comprehensive bundles of PBM components encompassing 107 different PBM measures, divided into six bundle blocks can act as a working template for the clinicians.
The first strategy is to manage the patient's preoperative anemia. The decision to transfuse red cells was based on expert opinion earlier which then shifted to the protocol-based approach. One such example is the development of the Maximum Surgical Blood Ordering Schedule. It was far better than the traditional “expert opinion” policy and it reduced the over-utilization of red blood cell units, however, it was not “personalized therapy.”
| Role of Preanesthetic Clinic in Precision Medicine|| |
The preanesthetic clinic plays an important role and is the hub of PBM. It is ideal to assess the patient 3–4 weeks before the planned procedure. At this point, medical history, biological condition, identification of anemia, the coagulation status, and the medications influencing the same will be reviewed. The nutritional anemia can be managed conservatively at this stage. Timely optimization of cardiopulmonary function is feasible to increase the patient's tolerance to anemia. Instead of unnecessary top-up transfusions, erythropoietin-stimulating agents along with the hematinics will be considered.
The second strategy of PBM is the optimization of the coagulation status of the patient. Identifying patients who are at risk of bleeding, patients on anticoagulants or antiplatelet therapy helps in providing patient-specific therapy.
| Role of Point of Care Testing in Precision Medicine|| |
Point of care testing (POCT) has changed transfusion practices, especially in Critical Care units, Operation theaters, trauma and casualty units, and transplantation settings. The commonly used POCTs that influence transfusion decision-making are hemoglobin, Hct, international normalized ratio, platelet function, blood gas level, and viscoelastic testing. Real-time monitoring of hemostasis, hemodynamic status of the patient can be achieved with the reduced turnaround time. Researchers have shown that POCTs significantly reduced the transfusion rate and improved patient care.
| Patient-specific Testing Strategy to Reduce Iatrogenic Blood Loss|| |
The iatrogenic blood loss varies approximately from 25 to 75 mL per day per patient. Koch et al. have estimated that around 74% of the patients develop hospital-acquired anemia and it is very common in intensive care units. It is mainly due to the frequent collection of blood samples for the battery of tests and unnecessary repetition of some of the tests which are not useful in patient management. The patient-specific testing strategy involves evaluation of the need for the test, use of pediatric collection tubes, pediatric culture bottles, and reduction in the frequency of testing to minimize blood loss.
| Calculations in Patient Blood Management Leading to Patient-specific Treatment|| |
Some calculations help us in providing patient-specific transfusion support. The blood volume of the patient is substituted in a formula to estimate the red cell volume. Similarly, depending on the blood volume and the preoperative Hct level the tolerable red cell volume is calculated for a patient. The patient-specific calculation before elective procedures will help in predicting the peri-operative blood loss and thus the transfusion requirement.
Hauser et al. have presented calculators to make the transfusion medicine practice easy. One can apply these equations to calculate the dosage of blood products, calculation of fluid volumes, corrected count increment following platelet transfusion which enables the application of precision medicine. One such example is to estimate the volume of cryoprecipitate for the replacement of fibrinogen, we can use the following formula:
Number of units of cryoprecipitate required = (desired fibrinogen increment, mg/dL × plasma volume, dL)/fibrinogen content in cryoprecipitate, mg/unit
There are online sources to access such equations which facilitate quick calculations and are handy for the clinicians to use it bedside.(https://www.mdcalc.com/search? ilter = transfusion + medicine).
| Artificial Intelligence for Precision Medicine|| |
Artificial intelligence (AI) has enabled us to take a giant leap in the field of transfusion medicine. The automation in the laboratory, software, data integration facility, and machine learning algorithms are few to mention. With the help of AI, clinicians can take a quicker decision and the machine learning algorithms will assist them to come up with an accurate judgment on the blood component transfusion. 'Capacity for Clinical Decision Support system' facilitates implementation of PBM and requires the clinician to justify the indication for transfusion when the request is outside the approved guideline.
| An Algorithmic Approach for Precise Transfusion Therapy|| |
Precision medicine involves classifying individuals into subpopulations of the patient depending upon patient characteristics, susceptibility, and accordingly tailoring the treatment. The algorithms used to provide transfusion therapy follow the same principles. Hemotherapy decision-making becomes easier if we adopt the algorithms incorporating the patient-specific factors and the POCT and the results of other laboratory tests. For example, if we consider patients undergoing cardiac surgery, hemostatic management can be done by using well-established algorithms.
| Interdisciplinary Approach for Precision Medicine|| |
The third strategy of PBM is interdisciplinary, a multimodal approach adopted to limit the use of allogeneic blood. To advance toward precision medicine, merging clinical, surgical, biomedical engineering knowledge with transfusion medicine is necessary. The use of modern surgical techniques, laparoscopic surgeries, minimally invasive procedures to reduce blood loss, controlled hypotension, cell salvage is some means of PBM that needs interdisciplinary collaboration.
| Optimal Blood use with Patient-centric Decision Making|| |
The fourth strategy of PBM is patient-centered decision-making. The Network for the Advancement of PBM, Hemostasis and Thrombosis (NATA) in collaboration with the International Federation of Gynaecology and Obstetrics, the European Board and College of Obstetrics and Gynaecology, and the European Society of Anaesthesiology developed a multidisciplinary consensus statement for PBM in obstetrics. The recommendations have been mentioned regarding the screening, management of patients with anemia during pregnancy, and the restricted use of RBC transfusion. Trial of oral iron, further evaluation by checking serum ferritin, ruling out hemoglobinopathy, and IV iron infusion if they fail to respond to oral therapy is recommended in a subpopulation of pregnant women with microcytic hypochromic anemia. Such PBM strategies though simple play a major role in reducing blood transfusion.
| The Barriers or Challenges to Implementation of Patient Blood Management|| |
In the present healthcare system, most of the patients report to the hospital just before the day of surgery. The treatment modalities such as conservative management of preoperative anemia are time taking. Creating awareness about the advantages of PBM, among the patients and the family members is most important. It needs a multidisciplinary approach, and good clinical collaboration is the key to the success of PBM. Currently, there is a lack of trained personnel with expertise in this area of Medicine. However, PBM is a paradigm shift and will take time to come to routine practice in the field of Transfusion Medicine.
| References|| |
Committee on a Framework for Development a New Taxonomy of Disease; National Research Council. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease. Washington, D.C: The National Academies Press 500; 2011. p. 109.
Cohn CS, Delaney M, Susan T Johnson LM, editors. Technical Manual. 20th
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Meybohm P, Richards T, Isbister J, Hofmann A, Shander A, Goodnough LT, et al.
Patient blood management bundles to facilitate implementation. Transfus Med Rev 2017;31:62-71.
Meybohm P, Zacharowski K, Weber CF. Point-of-care coagulation management in intensive care medicine. Crit Care BioMed Central 2013;17:218.
Koch CG, Li L, Sun Z, Hixson ED, Tang A, Phillips SC, et al.
Hospital-acquired anemia: Prevalence, outcomes, and healthcare implications. J Hosp Med 2013;8:506-12.
Hauser RG, Kwon RJ, Ryder A, Cheng C, Charifa A, Tormey C. Transfusion medicine equations made internet accessible. Transfus Med Rev 2020;34:5-9.
Brown RE, Dorion RP, Trowbridge C, Stammers AH, Fitt W, Davis J. Algorithmic and consultative integration of transfusion medicine and coagulation: A personalized medicine approach with reduced blood component utilization. Ann Clin Lab Sci 2011;41:211-6.
Enriquez LJ, Shore-Lesserson L. Point-of-care coagulation testing and transfusion algorithms. Br J Anaesth 2009;103 Suppl 1:i14-22.
Muñoz M, Robinson S, Christory F, Samama C, Hardy J. Patient blood management in obstetrics: Management of anaemia and haematinic deficiencies in pregnancy and in the post-partum period: NATA consensus statement. Transfus Med 2018;28:22-39. doi: 10.1111/tme.12443.