DIAGNOSTIC TESTING IN PATIENT BLOOD MANAGEMENT PROGRAMS

Transcription

1 DIAGNOSTIC TESTING IN PATIENT BLOOD MANAGEMENT PROGRAMS The Role of Diagnostic Point-of-Care Testing Diagnostic testing is an essential component of Patient Blood Management. The accurate assessment of the true causes of bleeding dysfunction facilitates the employment of evidence based, goal directed therapy to rapidly prevent and treat excess blood loss. Sherri Ozawa RN Clinical Director, Institute of Patient Blood Management, Englewood Hospital Medical Center, Englewood, NJ Supported by a grant from Tem Systems, Inc. (ROTEM )

2 What Is the Issue? Blood transfusion is the most common procedure performed in US hospitals 1 Every year, approximately 14 million units of packed red blood cells are used 2 One in ten hospitalized patients who undergoes an invasive procedure is transfused 3 It is estimated that -% of transfusions are administered without appropriate clinical justification 4 Modifiable risks that can reduce patient exposure to blood products 5 94% of transfusions in surgical patients can be attributed to modifiable events. Low preoperative hemoglobin levels Excessive surgical blood loss Inappropriate transfusion practices What Factors Impact Bleeding Related Complications? Evolving technology in health care can predispose patients to bleeding complications. 6 Progressive widespread use of anticoagulant and antiplatelet therapeutics Technological advances that enable complex and lengthy surgical procedures Advancing age of the general population with associated comorbidities that predispose to bleeding related complications Why Should I Care? Unanticipated surgical bleeding is expensive and associated with poor outcomes 7 Rate of bleeding-related complications was almmost 30% in commonly performed operating procedures Incremental length of stay associated with bleeding-related complications or transfusions was 6 days Incremental cost per hospitalization associated with bleeding-related complications and adjusted for covariates was: $1,279 -$2,5 depending on type of surgery Achieving hemostasis in surgical patients is finding that fine balance between perioperative bleeding and pathological thrombosis; the two extremes of preventing a patient from bleeding to death while also preventing them from clotting to death. Sherri Ozawa RN SABM Copyright 14 2

3 Goals of Diagnostic Testing in Patient Blood Management Rapid diagnosis and arresting blood loss by accurately assessing true causes of bleeding dysfunction 8 Use both quantitative and qualitative measures to assess true coagulation status Recognize the major mechanism of a developing coagulopathy Use goal directed diagnostic testing to direct and establish treatment goals Conventional Coagulation Testing - What Do We See? Blood tested almost one hour after it is drawn Blood is drawn. It s transported to the laboratory. It s centrifuged. The cells are removed. Calcium and activators are added. Clot initiation (ATT and PTT) is measured. Routine plasma coagulation tests only reflect 1-2% of the entire coagulation process 9 Only 5% of total thrombin has been generated when the coagulometer stops Only plasma is analyzed Interaction of platelets (or any other cells) are not assessed Interaction with the coagulation system, fibrinolysis or FXIII is not assessed Coagulation Final clot PT APTT Fibrinogen Clauss Time (sec) SABM Copyright 14 3

4 Mildly abnormal test results are associated with hemostatically adequate coagulation factor concentrations 10 Below is a graph comparing the percentage of available clotting factors with INR values % of factors are required to produce a clot (INR 1.7) INR may be elevated, but patient is still able to clot 100 % ml/kg FFP = 4 L fresh plasma CLOTTING FACTORS 50 % 30 % 15 ml/kg FFP zone of normal hemostasis zone of normal anticoagulation INR New Insights: Viscoelastic Diagnostic Testing Basic principles of rotational thromboelastometry (ROTEM ) 11 A citrated blood sample is placed is a stationary cup with calcium chloride and a coagulation activator. The rotating pin is lowered into the blood. Clot formation changes the torque between the pin and the cup. Diode Light detector Data processor Clot firmness (mm) 100 CFT Alpha A10 MCF ML CT Time (min) 50 Pin Blood CT CFT Alpha A10 MCF ML Closing time Clot forming time Alpha angle Amplitude 10 min after CT Maximum clot firmness Maximum XXXX SABM Copyright 14 4

5 Measurements include coagulation time (CT;sec), clot formation time (CFT; sec), -angle (degrees), amplitude at 10 minutes after CT (A10; mm), maximum clot firmness (MCF; mm), and maximum lysis (ML; % decrease decrease min after MCF). Morphology and clot formation changes are dependent on clotting defect 11 Below are examples of ROTEM traces using the EXTEM test. normal test result reduced MCF delayed initiation of coagulation prolongued CT and reduced MCF hyperfibrinolysis SABM Copyright 14 5

6 Allows assessment of clotting defect and replenishment of what is needed without additional blood components Below is an algorithm using the results of viscoelastic testing and a summary of therapeutic options. Viscoelastic POC Testing (TEG ) guided therapy was superior to conventional coagulation tests in trauma patients 12 Holcomb (12) evaluated a series of 1974 trauma patients, 25% of whom presented in shock and 28% of whom were transfused. The authors found that TEG, Haemonetics, predicted RBC transfusion and massive transfusion better than PT or PTT. TEG was superior to fibrinogen in predicting plasma transfusion, and superior to platelet count in predicting platelet transfusion. SABM Copyright 14 6

7 Advantages compared to conventional coagulation testing 11,13 Conventional coagulation testing only provides limited information on the underlying coagulation disorder Whole-blood viscoelastic tests such as rotational thromboelastometry (ROTEM) or thrombelastography (TEG) offer a more comprehensive insight into the coagulation process in trauma Results are available within minutes and they provide information about: Initiation of coagulation, the speed of clot formation, and the quality and stability of the clot Viscoelastic testing has the potential to guide us to the defect and allow the patient to receive only the appropriate blood component that will correct their defect. Aryeh Shander MD, Clinical Professor of Anesthesiology, Medicine and Surgery, Icahn School of Medicine at Mt Sinai, New York Viscoelastic tests have the potential to guide coagulation therapy according to actual needs of each patient and reducing the risks of over or under transfusion Goal-directed therapy with specific hemostatic drugs, coagulation factor concentrates, and blood components In several cohort studies, this POC-based management was associated with: Reduced transfusion requirements Reduced incidence of transfusion associated adverse events Improved patient outcomes Summary The superior information obtained with viscoelastic testing is critical to better direct effective therapeutic interventions in patients with coagulation issues. Optimizing coagulation is a fundamental principle of Patient Blood Management and along with other evidence based interventions, can positively impact patient outcome. Implementing organized PBM programs, which incorporate advanced capabilities such as viscoelastic testing result in better clinical decision making, cost savings, and optimal patient care. Optimizing Coagulation IMPROVED PATIENT OUTCOMES Interdisciplinary Blood Conservation Modalities What is Patient Blood Management? The timely application of evidence based medical and surgical concepts designed to manage anemia, optimize hemostasis, and minimize blood loss in order to improve patient outcomes. - Society for the Advancement of Blood Management (SABM.org) Patient-Centered Decision Making Managing Anemia SABM 13 SABM Copyright 14 7

8 References 1. Agency for Healthcare Research and Quality. Healthcare Cost Utilization Project Statistical Brief. #149.Most Frequent Procedures Performed in Hospitals Accessed July 18, Department of Health and Human Services, National Blood Utilization and Collection Survey, bloodsafety/nbcus/index.html 3. Agency for Healthcare Research and Quality. HCUP Facts and Figures: Statistics on Hospital-Based Care in the United States, 07. Available at: us.ahrq.gov/reports/factsand gures/07/ pdfs/ff_report_07.pdf - Accessed June 16, Shander A, Fink A, Javidroozi M, Erhard J, et al.appropriateness of allogeneic red blood cell transfusion: the international consensus conference on transfusion outcomes. Transfus Med Rev. 11 Jul;25(3): e53 5. Shander A, Javidroozi M, Perelman S, et al Mt Sinai J Med. Jan-Feb Shander A, Kaplan L, Harris M et al. Topical Hemostatic Therapy in Surgery: Bridging the Knowledge and Practice Gap J Am Col Surg. 14; in press. 7. Stokes ME, Ye X, Shah M, Mercaldi K, Reynolds MW, Rupnow MF, Hammond J. Impact of bleeding-related complications and/or blood product transfusions on hospital costs in inpatient surgical patients. BMC Health Serv Res. 11; 11: Armand R, Hess JR. Treating coagulopathy in trauma patients. Transfus Med Rev. 03; 17(3): Mann KG, Brummel K, Butenas S. What is all that thrombin for? J Thromb Haemost. 03 Jul;1(7): Dzik WH, in Mintz PC ed. Transfusion Therapy: Principles and Practice, 2nd edition. AABB Schöchl H, Maegele M, Solomon C, Görlinger K, Voelckel W. Early and individualized goal-directed therapy for traumainduced coagulopathy. Scand J Trauma Resusc Emerg Med ;: Holcomb JB, Minei KM, Scerbo ML, Radwan ZA, Wade CE, Kozar RA, Gill BAlbarado R, McNutt MK, Khan S, Adams PR, Mc- Carthy JJ, Cotton BA. Admission rapid thrombelastography can replace conventional coagulation tests in the emergencydepartment: experience with 1974 consecutive trauma patients. Ann Surg. 12 Sep;256(3): Lier H, Vorweg M, Hanke A, Görlinger K. Thromboelastometry guided therapy of severe bleeding. Essener Runde algorithm. Hamostaseologie. 13;33(1): SABM Copyright 14 8