Introducing WHITE PAPER

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1 Introducing WHITE PAPER This white paper presents the TEG 6s device, a revolutionary approach to viscoelastic hemostatic assays (VHAs) science by the introduction of an innovative, all-in-one cartridge. The TEG system is a real-time analyzer of whole blood measuring the viscoelastic properties of the hemostasis process and allowing for individualized goal-directed therapy. It provides rapid, comprehensive and accurate identification of an individual s hemostasis condition, in a laboratory or in the context of near-patient testing, which allows clinicians to drive personalized, clinically and economically sound treatment and monitoring decisions. The demonstrated benefits of using TEG: In cardiac surgery, TEG allows a reduction in blood product usage by providing clinicians with information to help determine which specific blood products are needed to stop bleeding, and accurately identifies the need for re-operations by ruling out a coagulopathic cause of bleeding. For patients on antiplatelet medications, TEG helps to stratify bleeding risk and reduce time to schedule coronary artery bypass graft (CABG) surgery and length of stay. TEG is more predictive than conventional coagulation tests (CCTs) in anticipating massive transfusion, delivers results faster for trauma physicians and guides specific blood products and high risk drugs to stop bleeding in trauma patients and predicts those at high risk of pulmonary embolism (PE). (3-8) TEG helps to stratify risk of thrombotic events by helping clinicians determine which patients are at risk of thrombotic events and to determine the effectiveness of PY agonists. TEG helps to stratify risk of deep vein thrombosis and PE in ICU patients and improves adequate use of expensive pharmaceuticals (rfviia, fibrinogen).

2 The TEG 6s technology innovation. TEG 6s measures the same viscoelastic properties as the TEG 5. The new measurement technique associated with microfluidic sample preparation can be appreciated by its simplicity of use as well as the precision and repeatability of its results. TEG 6s advances the TEG 5 legacy through simple, smart and reliable design.

3 . Hemostasis and TEG INTRODUCTION Coagulation is a complex physiological process. The cell-based model of hemostasis provides a valuable framework for explaining the complex physiological process of coagulation. The model includes three phases: initiation, amplification and propagation (Figure ). () Figure. Cell-based model of hemostasis. [Reproduced from Hoffman M, Monroe III DM. A cell-based model of hemostasis. Thromb Haemost ;85: Copyright 5 with permission from Schattauer] The initiation phase involves activation of several coagulation factors via tissue factor. During the amplification phase, platelets are activated and further activation of coagulation factors occurs. Coagulation factor X is activated on the platelet surface in the propagation phase, and a complex of activated factor X with activated factor V converts large quantities of factor II (prothrombin) to thrombin ( thrombin burst ), leading to the generation of a fibrin matrix. 3

4 What are viscoelastic hemostatic assays (VHAs)? VHAs are performed to assess coagulation in a sample of whole blood. Reagents are added principally to trigger coagulation and, in some VHAs, to block or stimulate the effects of certain constituents. In the TEG 5 device, the blood is contained within a cup and a stationary pin is immersed in the blood (Figure A). () The cup rotates left and right in an oscillatory motion at a set speed through an arc of As the clot starts to form, it begins to bind to the cup and pin causing the pin to oscillate with the cup (Figure A). The rate with which movement of the pin increases is a function of clot development. As coagulation progresses, fibrin platelet bonding increases the strength of the link between the cup and pin, and increasing torque is applied to the pin. The strength of fibrin platelet bonding determines the magnitude of the pin s motion, with strong clots moving the pin to a greater extent. Thus, the magnitude of the output is directly related to the strength of the clot. If lysis occurs, fibrin platelet bonding is reduced and movement of the pin is diminished. The extent of the pin s rotation is converted into an electrical signal and then to a tracing that reflects the profile of clot formation. Viscoelastic parameters are measured as follows (Figure B): R (in min) is the time elapsing between initiation of the test and the point where clotting provides enough resistance to produce a mm amplitude reading on the TEG tracing. This parameter represents the initiation phase of coagulation triggered by enzymatic clotting factors. A prolonged R value is indicative of slow clot formation. ACT (RapidTEG parameter, in sec). The RapidTEG test incorporates both tissue factor and kaolin to accelerate coagulation versus the conventional kaolin test. ACT is another way to measure initiation of the clotting phase like R time does in the Kaolin test and is equivalent to the activated clotting time (a stand-alone nearpatient coagulation test). A prolonged TEG-ACT value is indicative of slow clot formation. Maximum amplitude (MA, in mm) is the point at which clot strength reaches its maximum, and reflects the end result of maximal platelet fibrin interaction via the GPIIb/IIIa receptors. K (in sec) is the time interval between the split point and the point where fibrin cross-linking produces a mm amplitude reading on the TEG tracing. 4

5 α angle (in ) is the angle formed by the slope of a tangent line from the tracing at the midpoint between the R and the K time. The K and α angle parameters reflect the rate of clot formation or the cleavage of fibrinogen into fibrin mediated by thrombin. LY3 (%) is the percentage reduction in amplitude 3 minutes after reaching MA. After the clot has formed, it is degraded by fibrinolytic factors within the blood and the amplitude decreases over time. By measuring the extent/speed of amplitude reduction, clot lysis can be assessed. Figure. The principles by which TEG functions. A. Diagram of the TEG 5. B. Current diagram of a TEG tracing showing the basis of the principal viscoelastic parameters. TEG versus conventional coagulation tests. A variety of assays can be run on the TEG device, providing insights into different aspects of coagulation. Although von Willebrand factor is not detected, the effects of most whole blood components (e.g. coagulation factors, platelets, fibrinolytic factors and inflammatory cells) are included in TEG analysis. Also, the full process of coagulation and subsequent clot lysis is followed. TEG results therefore provide a good reflection of the cell-based model of hemostasis. In contrast, CCTs (e.g. prothrombin time [PT], activated partial thromboplastin time [aptt]) are performed using plasma samples. The removal of platelets and other blood cells means that such tests are limited in the extent to which they reflect physiological clotting. (3) CCTs are stopped after <5% of the total thrombin has been generated, further limiting the insight they provide. (4) Compared with CCTs, TEG provides more comprehensive assessment of the patient s coagulation status. (5,6) 5

6 Importantly, TEG results are usually available more quickly than CCTs. In one study, RapidTEG results were available within 5 5 minutes (depending on the parameter), compared with 48 minutes for CCTs (p<.). (5) This can increase the speed with which appropriate hemostatic therapy is administered and, potentially, improve patient outcomes including increased survival. (7) Through TEG, the TEG PlateletMapping assay enables platelet function to be assessed. Therefore, TEG analysis may be compared with methods specifically designed for monitoring platelet function. Light transmittance aggregometry (LTA) was considered the gold standard assay, but the method requires skilled technicians and results are subject to variability. (8) Alternative methods are available with shorter turnaround times and more convenient sample preparation but still needing a skilled operator. One example is the multiple electrode aggregometry analyzer, a device which measures platelet aggregation by electrical impedance. (8) In most clinical settings, platelet tests must be performed in addition to coagulation testing. TEG enables both coagulation and the effects of antiplatelet therapy to be assessed using one device. Therefore, by using TEG, the need for a specific platelet assessment device may be removed. 6

7 . The TEG Test Suite CLINICAL VALUES Building upon the TEG 5, up to four assays can be run simultaneously on the TEG 6s. This is achieved by using one of the two microfluidics cartridges available (described below), both prepackaged with all the required reagents. Global hemostasis cartridge (CM citrated) Kaolin TEG (CK). The standard TEG assay, which uses kaolin for activation of coagulation. Kaolin activation is classically described as intrinsic pathway activation, but the cell-based model of coagulation has rendered this terminology obsolete. The hemostasis profile resulting from kaolin activation provides a measure of the time it takes for the first measurable clot to be formed, the kinetics of clot formation, the strength of the clot and the breakdown of the clot, or fibrinolysis. Clinical value: Overall functional assessment of coagulation, identifying underlying hemostatic characteristics and risk of bleeding or thrombosis. For example, in trauma, deficiencies in/consumption of coagulation factors may be identified as well as the stability of the clot. Kaolin TEG with heparinase (CKH). The addition of heparinase to the standard TEG assay eliminates the effect of heparin in the test sample. Clinical value: In conjunction with Kaolin TEG, assessment of the presence of systemic heparin or heparinoids. In cardiac surgery, it provides a heads up before the patient comes off pump and, after protamine administration, it shows whether heparin has been reversed. RapidTEG (CRT). An accelerated assay with tissue factor and kaolin for activation that would be classically described as both extrinsic and intrinsic. Clinical value: Rapid assessment of coagulation properties, enabling appropriate hemostatic therapy to be administered with minimal time delay. It may be used in conjunction with the 7

8 Functional Fibrinogen assay to pinpoint fibrinogen or platelet deficiency, and the impact of the ratio of platelets and fibrin to the resulting clot strength. TEG Functional Fibrinogen (CFF). Tissue factor is used for coagulation activation that would be classically described as extrinsic, with platelet function inhibited by a GPIIb/IIIa inhibitor such that the resulting contribution of the functional fibrinogen to clot strength is exhibited. By subtracting this functional fibrinogen contribution from the overall clot strength, the specific contribution of platelet function is extrapolated. Clinical value: Provides the overall contribution of fibrin to clot strength. In conjunction with CK or CRT, this assay enables the contributions of fibrinogen and platelets to clot strength to be determined separately. Results may be valuable for guiding fibrinogen supplementation or platelet transfusion. Platelet mapping cartridge Heparinase Kaolin (HKH). This assay is similar to CKH run on the global hemostasis cartridge and measures the overall clot strength arising from the contributions of thrombin and fibrin. It is a reflection of the maximum contribution of platelet function to the total clot strength no impact of any inhibition. Activator F (ActF). Reptilase and factor XIII produce a clot with zero platelet contribution. The presence of heparin inhibits thrombin activity. ADP and AA. Assays performed with ActF, designed to measure agonist-induced (adenosine diphosphate [ADP] or arachidonic acid [AA]) clot strength. Unlike standard TEG analyses, the absence of thrombin provides sensitivity to common antiplatelet agents such as aspirin and clopidogrel. ADP and AA clot strength measurements are compared with those from HKH and ActF to ascertain the response to each agonist. Clinical value: Assessment of personalized platelet inhibition and aggregation enables antiplatelet therapy to be monitored according to the patient s specific response to the drug. In cardiac surgery patients, TEG PlateletMapping can help ensure that surgery is timed or in emergency cases risk management measures are put in place so a patient s specific response to the antiplatelet therapy does not result in increased bleeding risk nor 8

9 increased thrombosis risk. In trauma, ADP responsiveness has been correlated with a patient s need for transfusion. TEG 6s cartridges Simple. The assays described above are performed on TEG 6s using one of two microfluidic cartridges (see section 5), each of which has four analysis channels utilizing minimal blood volumes of 3 μl for all four channels (Table ). Cartridge Sample type Assays (one per channel) Parameters Kaolin TEG (CK) R, K, α angle, MA, LY3 Global hemostasis Citrated Kaolin TEG with heparinase (CKH) RapidTEG (CRT) R, K, α angle, MA ACT, R, K, α angle, MA, LY3 TEG Functional Fibrinogen (CFF) MA Kaolin TEG with heparinase (HKH) R, K, α angle, MA, LY3 Platelet mapping Heparinized Activator F (ActF) ADP MA MA, %Agg/Inh AA Table. Configuration of TEG 6s cartridges. MA, %Agg/Inh The TEG 6s cartridges enable multiple assays to be run automatically using blood samples that are either citrated or heparinized, without the need for reagent preparation or accurately controlled pipetting. Thus, the process for running multiple TEG assays is greatly simplified. By eliminating manual preparation, variability is reduced and the automated process therefore improves quality assurance. Smart. Each TEG assay provides a variety of parameters relating rate of clot initiation, clot strength and rate of clot breakdown. Therefore, simultaneous performance of several assays gives rise to a defined picture of global hemostasis with identifiable activity in the three key areas of initiation, strength and breakdown. When using the global hemostasis cartridge, the interpretation of results may be simplified by focusing initially on CK R, CRT MA and CFF MA. The function of these three parameters can be assessed within minutes, enabling informed treatment decisions to be taken quickly. The insight gained from the initial three parameters may be supplemented by considering LY3 from CRT for clot breakdown as well as the difference between R values obtained with CK and CKH for 9

10 heparin presence. Consequently, TEG may be considered as a key tool for optimizing patient management. Summary TEG 6s provides a single platform with an automated system utilizing a global hemostasis and platelet mapping cartridge to test coagulation in all major TEG assays. The process for performing multiple TEG assays is faster and greatly simplified with TEG 6s. Most comprehensive insight into the patient s coagulation status is now obtained within minutes.

11 3. Global Assays Concept QUICK, SIMPLIFIED, ACCURATE TEG 6s enables multiple assays to be performed simultaneously from a single blood sample. By superimposing the results of different assays (Figure 3), a detailed clinical picture of hemostasis is obtained in as little as minutes. Figure 3. Multi-test approach: global hemostasis. Until now, different TEG assays had to be performed individually, with each assay requiring careful preparation and controlled pipetting. Automation provided by the TEG 6s platform greatly simplifies and standardizes the process, ensuring accuracy. From the global hemostasis cartridge, the following parameters are rapidly available: CK R, providing information on clot initiation and thrombin generation. CFF MA, providing information on the contribution of fibrinogen to clot strength. CRT MA, providing information on overall clot strength. Additionally, significant fibrinolysis can be apparent from the CRT LY3 parameter. A complete picture is provided, allowing goal-directed therapy to be determined quickly. Summary The global assays concept provides: Quick, complete picture of hemostasis. Simplified process (no need for careful preparation of individual assays). Consistent accuracy, due to assay standardization.

12 4. TEG Clinical Outcomes and Cost-Effectiveness LITERATURE REVIEW Scientific literature shows that the use of TEG can help clinicians to improve patient outcomes and reduce costs by analyzing the coagulation state of a blood sample. By individualizing goaldirected coagulation management, it is possible to reduce inappropriate blood transfusions, and stratify patients according to their risk of bleeding and/or thrombotic complications. There is consequently a great opportunity to achieve substantial cost savings with a goal-directed TEG program. Orthotopic liver transplant. This setting is associated with a wide range of hemostatic abnormalities and was one of the earliest fields to adopt thrombelastography (TEG). In this setting, coagulation monitoring is critical and TEG is now used as a standard of care. (9) Guidelines from the European Society of Anaesthesiology (ESA) for management of severe perioperative bleeding recommend the use of coagulation monitoring such as TEG for targeted management of coagulopathy during liver transplantation. () Further to the advantages of using TEG for clinical monitoring of coagulation, a randomized clinical trial of patients undergoing orthotopic liver transplant demonstrated that the use of TEG can also significantly decrease fresh frozen plasma (FFP) transfusion. () Cardiovascular surgery. VHAs have been used extensively in this setting to identify the cause of bleeding and to guide the transfusion of appropriate blood products. A recent NICE (National Institute for Health and Care Excellence, UK) diagnostics guideline recommends viscoelastic devices such as TEG, to help monitor coagulation during and after cardiac surgery, because the use of VHAs was shown to be associated with lower mortality, a reduced probability of experiencing complications, and less transfusion and hospitalization. () Furthermore, when coagulopathy is suspected, the American Society of Anesthesiologists (ASA) advocates the use of VHAs to identify and treat the cause of bleeding. (3) Similarly, the ESA guidelines recommend TEG to guide hemostatic therapy during cardiovascular surgery. () A range of prospective, randomized studies have shown that the implementation of TEGbased algorithms can effectively decrease allogeneic blood products transfusion including,

13 FFP, and/or platelets as well as indirectly red blood cells (RBC) by resolving coagulopathies that prevent the drop in hemoglobin. (4-7) In addition, TEG-guided transfusion has also been shown to reduce blood loss after cardiovascular surgery compared with transfusion algorithms based on CCTs. (6,7) TEG-based management also helps to monitor the effects of hemostatic therapies to ensure an appropriate balance between hemorrhage and thrombosis is achieved. For example, while rfviia can successfully be used in cardiac surgery, (8) its administration is known to be associated with increased mortality, (9) and is generally only considered as a rescue therapy in the treatment of uncontrolled bleeding. Unlike CCTs, TEG can effectively evaluate the hemostatic effects of rfviia thereby allowing for a close monitoring of the patient s coagulation status in such critical situations. (-) Trauma. In Europe, reviews by NICE () and Cochrane (3) have not recommended the use of VHAs in trauma mainly due to the lack of randomized controlled trials. However, various expert committees are recommending the use of VHAs in trauma and the management of massive hemorrhage. (,4,5) Furthermore, the American College of Surgeons Trauma Quality Improvement Program (ACS TQIP) have released cut-off points for transfusion triggers for Kaolin TEG or RapidTEG assays. (6) TEG assays are increasingly used in trauma where VHAs have been shown to be beneficial for identifying coagulopathy and anticipating the need for massive transfusion. (7) Johansson and colleagues developed a TEG-guided algorithm based on cut-offs that correlated to transfusion and outcomes during an observational trial. This was followed by demonstrating the reduction in hemorrhagic bleeding in a prospective interventional trial using TEG-guided resuscitation. (8,9) In a prospective controlled study investigating the use of TEG in massive transfusion protocols compared with CCTs, the authors found that correction of the TEG parameters was associated with survival. (3) Similar observations were made in a retrospective study showing that TEG R >6 min can be used as an independent marker of risk factor for death in trauma patients. (3) Finally, a prospective study, involving 7 patients across multiple level I trauma centers, revealed that TEG can be used to predict the need for massive transfusion in the first 6 hours of admission. (5) These observations show that the use of TEG allows for a reduction of transfusion requirements and leads to a more efficient management of traumatic bleeding. A recent update of the European guideline on management of bleeding and coagulopathy in trauma recommends the use of VHAs to assist in characterizing the coagulopathy and in guiding hemostatic therapy. (4) TEG significantly impacts on transfusion practices and has led to 3

14 initiatives from institutional blood banks, for example in Denmark, (3) to optimize transfusion therapy and increase survival in massively transfused patients. Additionally, transfusion guidelines and various transfusion algorithms, based on TEG parameters, have been proposed to guide appropriate usage of blood components and other hemostatic therapies (e.g. cryoprecipitate, fibrinogen concentrate, tranexamic acid) in a trauma setting. (6,8,9,33-38) Thrombotic management. In addition to its role in reducing blood loss and improving outcomes, TEG can also help to predict thrombotic complications. Two separate studies have demonstrated an association between TEG results and ischemic events or thrombotic complications in cardiac surgery. (39,4) Furthermore, TEG has been described to be more sensitive than CCTs for the identification of hypercoagulable states which are predictive of thromboembolic events including pulmonary embolism. (6,4,4) Anticoagulant or antiplatelet therapy is often stopped a few days before cardiovascular surgery to reduce the risk of perioperative bleeding while potentially increasing the risk of a thromboembolic event in the preoperative period. To minimize patient risk and time to schedule interventions, TEG PlateletMapping can be used to assess platelet function and predict thrombotic events post-operatively or after percutaneous coronary intervention (PCI). For example, the use of TEG has been shown to effectively lead to an earlier scheduling of CABG procedure with a reduction in time to surgery. (43) In addition, monitoring patients with TEG can help identify individuals who have failed to adequately stop antiplatelet therapy prior to non-cardiac surgery, preventing unnecessary cancellation while minimizing patient risk. (44) There is a great inter-individual variability in the response to antiplatelet therapy with some patients having minimal change in platelet function (resistance) while others can be qualified as hyper-responders. TEG can also help in the identification of those hyper-responders who are at high risk of bleeding, enabling the balance of thrombotic versus bleeding risk by tailoring antiplatelet therapy to each patient s needs. (45) The Society of Thoracic Surgeons published a practice guideline recommending the use of near-patient testing such as TEG to assess bleeding risk and identify patients with high residual platelet reactivity after usual doses of antiplatelet drugs, and who can undergo operation without elevated bleeding risk. (46) Cost-effectiveness. As demonstrated by an adequate blood products usage and improved clinical outcomes, the use of TEG across various clinical settings is cost-effective. The recent NICE diagnostics guideline describes viscoelastometry tests as being more effective and less costly than CCTs in cardiac surgery, with TEG saving an estimated 79 per cardiovascular surgery. () Similarly, Agarwal and colleagues were able to demonstrate that 4

15 the addition of TEG assays to their standard treatment algorithm for patients undergoing CABG, led to a 46% reduction of treatment costs. (7) The ESA guidelines also recommend the implementation of VHAs-based transfusion and coagulation management algorithms as a means to reduce transfusion-related costs in trauma, cardiac surgery and liver transplantation. () Summary Data from the literature have demonstrated that TEG is part of the whole picture of patient blood management strategies and can effectively: Reduce blood products usage (FFP, RBC, platelets, cryoprecipitate). Improve adequate use of expensive pharmaceuticals (rfviia, fibrinogen). Allow for the stratification of the risk of thrombosis. Reduce hospital stay related costs (ICU length of stay, re-exploration, adverse reactions to blood transfusions, blood product waste, thrombotic episodes). () There is a growing body of evidence supporting the utility of TEG in predicting bleeding. (6) However, the utility of TEG in guiding the management of post-operative bleeding has been the main driver of adoption. (4) Additionally, TEG can identify hypercoagulable states in conditions such as acute coronary syndrome, trauma, obstetrics, liver transplant, cancer and stroke. (47,48) 5

16 5. TEG 6s Technology THE INNOVATION Microfluidic-based single cartridges. TEG 6s measures the same physical properties as TEG 5, with assessment of clot viscoelasticity throughout the coagulation process. TEG 6s assays are run using the same reagents as TEG 5, and measurement parameters are expressed in the same units with both devices. Thus, results obtained with TEG 6s can be interpreted in the same way as those obtained with TEG 5. Instead of the sample cup used with TEG 5, TEG 6s assays are performed in automatically loaded microfluidic cartridges designed for simultaneous performance of multiple TEG assays. Electronic quality control within the TEG 6s system eliminates the need for hands-on calibration of the device the only requirement is for an electronic calibration card to be used every 6 months during the product maintenance procedure by Haemonetics personal. An Individualized Quality Control Plan (IQCP) for the reagent cartridges is available by using patient blood and abnormal QC material. Simple sample preparation. Preparing the blood sample for TEG 6s analysis is very simple. There is no need for controlled pipetting or prior manipulation of reagents. The only requirement is to transfer an unmetered amount of blood (~3 μl) to the loaded cartridge from a sample tube with citrate or heparin. The addition of controlled volumes of blood to the four channels of the microfluidic cartridge (either global hemostasis or platelet mapping) and the addition of reagents at the correct concentrations is operator-independent. Any excess blood in the loading cartridge is transferred to a waste chamber upon completion of the assays. Resonance method of measuring clot strength. To measure clot strength with the resonance method, the sample is exposed to a fixed vibration frequency range ( 5 Hz). With LED illumination, a detector measures up/down motion of the blood meniscus. A fast Fourier transform (FFT) is used to identify frequency leading to resonance, and this is 6

17 converted to a TEG readout via a mapping function. Stiffer (stronger) clots have higher resonant frequencies and higher TEG readouts. Technically, the TEG 6s device functions differently from TEG 5, while still providing the same viscoelastic measurements. The use of microfluidic cartridges introduces the following important differences between the TEG 6s device and TEG 5 (Figure 4): Small sample size. TEG 6s assays are run with a much smaller volume per assay than TEG 5 ( versus 36 μl). Automated process. Without the need for manual manipulation of reagents or the blood sample, the scope for variability is practically eliminated with TEG 6s. In addition, the use of the device is intuitive. Innovative method. Whereas TEG 5 measures rotation of a pin immersed into a rotating cup, TEG 6s measures the frequency leading to resonance as the sample is vibrated. As well as enabling the assay to be performed on a smaller scale, the resonance method reduces sensitivity to external vibration, further increasing the consistency of results. Summary Concentric cylinders, 36 μl sample Outer cylinder moves, motion of the inner is resisted by a spring Clotting increases shear modulus, opposing spring force and resulting in the well-known tracing Amplitude increases with clot strength Downsides are large sample, sensitivity to vibration Figure 4. TEG 5 versus TEG 6s Measurement technique. Test cell μl Different sample geometry Single cylinder (ring), no pin Blood held in place by surface tension Clot strength measured by assessing the frequency of resonance Same physical property measured (shear modulus) With TEG 6s, microfluidic cartridges are used instead of the cup and pin of TEG 5. By assessing the clot s resonance frequency over time, the measurement method of TEG 6s differs from that with TEG 5. However, the two devices measure the same properties and results obtained with TEG 6s can be interpreted in the same way as those obtained with TEG 5. 7 Transfer of an unmetered amount of blood (~3 μl) from a sample tube to the loading cartridge are the only operator-dependent steps for TEG 6s sample preparation. Thereafter, the process is fully automatic.

18 6. Networked Solutions TEG MANAGER The TEG 6s analyzer is a connected device, with multiple TEG 6s analyzers able to network via a user interface to TEG Manager. Data from multiple devices can be centralized, with remote access to any connected TEG 6s, no matter where it is located (Figure 5). The TEG 6s is easy to use for near-patient testing, and physicians can view both active and historical test results to inform their treatment decisions. Figure 5. Networking TEG 6s devices via the TEG Manager allows remote viewing of test results anywhere within the hospital/institute network. TEG Manager. TEG Manager contains two components: a clinical Viewer to analyze test results, and a Device Manager for administration of all connected TEG 6s devices. These components are accessible anywhere in the hospital/institute network, with no need to install a desktop client, reducing the IT burden on the hospital. For the clinician: data is simple to consume. The TEG Viewer interface is functional, userfriendly and simple to use, displaying active and historical test results in near real-time (Figure 6). It is possible to review one test or multiple tests, search for past results, and invite others to see what you are viewing. When a sample is scanned, TEG Manager is able to retrieve patient s information from the hospital network and request confirmation of sample identification. 8

19 Test results and clinical reports are color-coded by cartridge, making it easy to assess results at a glance. TEG Viewer has been successfully trialed and will be available in languages. Figure 6. TEG Viewer interface. For lab managers and administrators: devices are simple to administer. Using Device Manager it is possible to access any connected device, directly from a web browser. Device Manager provides a dashboard for viewing the status of all connected TEG 6s analyzers in the institution, including operation, calibration, status, logs, firmware and cartridge configuration (Figure 7). This data can then be used to generate operational reports. User access for both the TEG 6s analyzers and TEG Manager can also be managed via Device Manager, including managing permissions and full data access reporting. Figure 7. Device Manager interface. 9

20 Moreover, TEG Manager can interface with the hospital s patient record system, allowing results from the TEG 6s to be sent directly to any room connected to the network where the data can be used to inform treatment decisions. Each night, TEG Manager sends operational data back to Haemonetics, allowing close monitoring of the performance and utilization of TEG 6s analyzers. Summary TEG Manager consists of two components: TEG Viewer for remote access to test results. Device Manager for administration of all connected TEG 6s analyzers. TEG Manager allows multiple TEG 6s analyzers to be networked and accessed anywhere within the hospital/institute network, and separates testing from data consumption. Through positive patient identification, TEG Manager ensures patients samples/results are correctly identified.

21 7. Bridging TEG 6s and TEG 5 SUPPORTING DATA Comparison of a new measurement technique with an established one is useful to demonstrate sufficient agreement for the new (TEG 6s) to replace or to be placed side by side with the old (TEG 5). A comparison study, to quantitatively compare the results of the TEG 6s to the TEG 5, was conducted in cardiovascular patients. Study design. Samples from patients >8 years of age were obtained at three different sites (n= evaluable patients per site). The samples were tested in duplicate with each reagent in both systems, leading to about 5, different tests in total (Figure 8). About % of the samples were also spiked with ReoPro, tpa, heparin, and tissue factor plus kaolin for the data to cover the full population spectrum. Figure 8. TEG 5 versus TEG 6s Method comparison.

22 Global hemostasis cartridge comparison to TEG 5. Mapping TEG 5 results to those of TEG 6s showed strong linear correlations between both devices, across different assay parameters (slopes close to and intercepts close to zero; Table and Figure 9). Assay Parameter r Intercept (95% CI) Slope (95% CI) Bias (95% CI) R (-.3, -.3).998 (.97, (4.7, 8.5) CK, CKH, CRT K (-.348, -.63).99 (.89,.95) 6.7 (4.5, 8.9) α angle (5.343, 8.973).85 (.63,.979) -5.9 (-6.6, -5.) CK, CKH, CRT, CFF, HKH MA (.9,.759).964 (.947,.98) -.9 (-.4, -.4) CK, CRT LY (-.8, -.48) Table. Similarities and bias between TEG 5 and TEG 6s. CI, confidence interval..6 (.958,.64).57 (.9,.95) Figure 9. Correlations between viscoelastic results obtained using TEG 6s and TEG 5 global hemostasis assays. Weighted Deming regression (obtained for R and MA) and Deming regression (LY3) fits are shown. The.95 confidence bounds were calculated with the jackknife method.

23 Platelet mapping cartridge comparison to TEG 5. The general agreement between TEG 6s and TEG 5 for the ADP and AA assays is provided in Table 3. Using the previously determined cut-offs, samples were determined to be ADP or AA inhibited (see section 8). Number of samples PA (95% CI) PPA (95% CI) NPA (95% CI) TEG 5 Cut-off TEG 6s Cut-off ADP Aggregation 6 7 (67, 78) 66 (6, 73) 9 (8, 97) <8 <83 ADP Inhibition 6 7 (67, 78) 66 (6, 73) 9 (8, 97) 7 AA Aggregation 67 9 (86, 94) 9 (87, 95) 9 (87, 95) <8 <89 AA Inhibition 67 9 (86, 94) 9 (87, 95) 9 (87, 95) Table 3. Agreement between TEG 5 and TEG 6s. CI, confidence interval; NPA, negative percentage agreement; PA, overall percentage agreement; PPA, positive percentage agreement. Summary These data demonstrate a substantial equivalence between TEG 6s and TEG 5. While these results were obtained using samples from cardiovascular patients, the comparability of hemostatic data between the two systems is applicable to any clinical setting. TEG 6s results linearly correlate with those of TEG 5 meaning that the TEG 5 medical decision points can be translated to TEG 6s with the data of this study. TEG 6s platelet inhibition cut-offs for ADP and AA assays are in agreement with those of the TEG 5. 3

24 8. Analytical Performance of TEG 6s SUPPORTING DATA A large analytical performance bench testing, multisite study was designed in accordance with Clinical Laboratory Standards Institute (CLSI) and FDA recommendations. Characterization of reference ranges. Reference range values for all eight assays (CK, CKH, CRT and CFF on the global hemostasis cartridge; HKH, ActF, ADP and AA on the platelet mapping cartridge) and parameters were established using venous blood samples collected from 65 healthy adults, across three sites. Volunteers were representative of a normal population distribution related to age, gender and race (Table 4). Samples were run as duplicates. Reference ranges were estimated using the CLSI C8-A3c Guideline ( on three reference sample groups, and constructed using the Shapiro-Wilk test to determine normality of the variable. If normality was satisfactory (p >.), then the reference interval was constructed as mean ± SD. If the Shapiro-Wilk test indicated non-normality (p <.), the 95% reference limits were used as estimates of the reference interval (Table 5). 8-3 years 3-5 years 5-7 years Demographics Age, n (%) Gender, n (%) Race, n (%) 56 (34) Caucasian Female 8 (49) 54 (33) African-American Male 84 (5) 55 (33) Other Table 4. Demographics of healthy volunteers. 9 (55) 6 (36) 5 (9) Global hemostasis Platelet mapping Assay Parameter Min Max Number of Number of Assay Parameter Min Max samples samples CK R R K K..9 5 α angle HKH α angle MA MA LY R CKH K α angle ActF MA 9 5 MA CRT CACT K α angle ADP MA MA LY CFF MA AA MA Table 5. TEG 6s reference ranges. 4

25 These are indicative of normal values in healthy individuals and do not indicate medical decision points. Conclusion. Reference range values for TEG 6s (all assays and parameters) are similar to those available in the TEG 5 and any differences can be associated with this CLSI methodology. Characterization of platelet mapping cut-offs and platelet inhibition detection ADP and AA cut-offs. Assay cut-offs were identified using the reference ranges data from healthy individuals (and determined by the % probability quantile for both the ADP and AA aggregation). Donors were screened to exclude the ones taking any known platelet inhibiting or hemostatic-altering drugs. The inhibition cut-offs values are based on the 9% probability quantile for AA and ADP Inhibition since Inhibition = Aggregation (Table 6). Number of samples Cut-off 9% CI (Low High) ADP Aggregation ADP Inhibition AA Aggregation AA Inhibition Table 6. TEG 6s cut-offs. CI, confidence interval. Platelet inhibition detection. The status of platelet inhibition in cardiovascular and PCI patients enrolled in the method comparison study (see section 8) was determined based on surgical status and inhibiting drugs. The diagnostic ability of the TEG 6s to detect platelet inhibition (based on the established cut-offs for ADP and AA, aggregation and inhibition) was evaluated for sensitivity and specificity (Table 7). Drug alone Patient numbers CPB Normal Unknowns Sensitivity (95% CI) Specificity (95% CI) Number of samples ADP Inhibition (63, 83) 83 (78, 88) 35 AA Inhibition (79, 89) 86 (8, 9) 35 Table 7. TEG 6s sensitivity and specificity to platelet inhibition. Both sensitivity and specificity of the TEG 6s ADP and AA assays are above 7%, criteria required for platelet mapping assays. Because sensitivity and sensitivity data highly rely on cutoff values and are affected by patients platelet inhibition status, receiver operating curve (ROC) analyses provide a better measure of comparison between TEG 6s and TEG 5. ROC analyses were conducted to estimate the ability of both ADP and AA aggregation/inhibition to 5

26 predict platelet inhibition with TEG 6s and TEG 5 (Figure ). Data show an improvement in the sensitivity with the TEG 6s due to the removal of the variability introduced by the operator. TEG 6s TEG 5 TEG 6s TEG 5 ADP-AUC (%) 88 (84 9) 77 (66 87) AA-AUC (%) 9 (89 95) 77 (66 87) Figure. Comparison of ROC curves obtained for the ADP and AA tests with the TEG 6s and TEG 5. AUC, area under the curve. The.95 confidence bounds were calculated with the jackknife method. Conclusion. This study proves that the TEG 6s ADP and AA assays are able to identify platelet inhibition based on the cut-off values established for ADP and AA aggregation/inhibition. More importantly, the ROC analyses validate the cut-offs derived from the reference ranges study. 6

27 TEG 6s repeatability and precision. This study was designed to establish the repeatability and precision characteristics for each assay parameters due to lot, operator, instrument and repeated measurement variations. Each sample was run in duplicate for five non-consecutive days. Each day, two operators ran six TEG 6s instruments in parallel and in duplicate, with two instruments running one reagent lot. A total of three reagent lots were evaluated each day. This resulted in observations per sample per operator each day for each test/parameter. Samples from three types of donors were used: hypocoagulable (coagulation level close to the lower limit of reference range for MA and upper limit of reference range for R), normal and hypercoagulable (coagulation level close to the upper limit of reference range for MA and lower limit of reference range for R). For the ADP and AA assays, samples were characterized as normal (donor with little or no platelet inhibition) or abnormal (donor with platelet inhibition levels above cut-offs for inhibition) (Table 8). Conclusion. This precision study is the first of its class in VHAs, both in its comprehensive nature (eight assays and parameters) and complexity (three donors, five days, three lots, instruments, three operators). All parameters were significantly below the 5% threshold set by the FDA. The operator-to-operator variability is very small, and close to <% for MA and <3% for R. The instrument to instrument variability is also very low (<%). 7

28 Assay Parameter Donor* Mean CK CKH CRT CFF R MA R C-ACT MA MA Hypo Normal Hyper Hypo Normal Hyper Hypo Normal Hyper Hypo Normal Hyper Hypo Normal Hyper Hypo Normal Hyper Assay Parameter Donor Mean AA ADP HKH Global hemostasis % CV Lot a Operator b Instrument c Day d Repetitions e Total f Platelet mapping % CV Total w/o day g Lot a Operator b Instrument c Day d Repetitions e Total f w/o Total day g % Agg* Normal. Abnormal 97.4 % Agg* Normal 99.4 Abnormal Hypo 59.6 MA Normal 63.4 Hyper 67.6 Hypo R Normal Hyper Table 8. TEG 6s precision data. Hypo, normal donor trending to hypocoagulable; hyper, normal donor trending to hypercoagulable. *For ADP and AA aggregation/inhibition, standard deviation values (SD) are given instead of % coefficient values (% CV=SD/mean) as high % CV values (due to large inter-individual variations) could be misleading. a variability due to difference in reagent lot; b variability due to the operator (operator and operator-by-reagent lot interaction); c between-instrument variability (within operator, reagent lot); d between-day variability (within instrument, operator, reagent lot); e repeatability (within-run); f total variability (reagent lot, operator, operator-by-reagent, instrument, day and repetitions); g total variability within day (reagent lot, operator, operator-by-reagent, instrument, and repetitions). Summary Performance studies confirmed that TEG 6s provides repeatable and precise results. Reference ranges in healthy individuals are close to those of the TEG 5. The great advantage of the TEG 6s, especially with respect to legacy VHAs (TEG 5, thromboelastometry), is the minimum user and instrument variability due to its fully automatic microfluidics-based technology

29 9. Conclusion TEG 6s Same. TEG 6s provides rapid, comprehensive and accurate assessment of an individual s coagulation status. TEG 6s measures the same viscoelastic properties as TEG 5, using resonance as opposed to rotational forces. With a close agreement between TEG 5 and TEG 6s, medical decision-making criteria developed for TEG 5 are directly applicable to TEG 6s. Simple. TEG 6s is a single platform with an automated system. Hemostasis and platelet mapping cartridges enable all major TEG assays to be performed, without the need for timeconsuming preparations. After collection of a single, unmetered blood sample, a comprehensive insight into the patient s coagulation status is available within minutes. Smart. With its microfluidic-based technology, TEG 6s advances the TEG 5 legacy through the use of single cartridges and minimal blood volumes. The networked solutions provided by the TEG Manager software separates testing from data consumption, improves patient positive identification and enables centralized instrument administration. Reliable. Due to a fully automatic process and assay standardization, TEG 6s provides consistent and accurate results. In a comprehensive quality assurance and performance study, all TEG parameters investigated showed minimal operator and instrument variability. to deliver personalized, clinically and economically sound hemostatic therapy. TEG plays a central role in individualized patient blood management; TEG-based transfusion algorithms can help reduce blood product usage, ensure appropriate use of expensive pharmaceuticals, and reduce hospital stay related costs. TEG 6s can be used for near-patient testing to predict bleeding and/or thrombosis risk empowering clinicians to deliver personalized, clinically and economically sound hemostatic therapy. 9

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34 38. Tapia NM, Chang A, Norman M et al. TEG-guided resuscitation is superior to standardized MTP resuscitation in massively transfused penetrating trauma patients. J Trauma Acute Care Surg 3;74: Gurbel PA, Bliden KP, Guyer K et al. Platelet reactivity in patients and recurrent events post-stenting: results of the PREPARE POST-STENTING Study. J Am Coll Cardiol 5;46: McCrath DJ, Cerboni E, Frumento RJ et al. Thromboelastography maximum amplitude predicts postoperative thrombotic complications including myocardial infarction. Anesth Analg 5;: Schreiber MA, Differding J, Thorborg P et al. Hypercoagulability is most prevalent early after injury and in female patients. J Trauma 5;58: Cotton BA, Minei KM, Radwan ZA et al. Admission rapid thrombelastography predicts development of pulmonary embolism in trauma patients. J Trauma Acute Care Surg ;7: Mahla E, Suarez TA, Bliden KP et al. Platelet function measurement-based strategy to reduce bleeding and waiting time in clopidogrel-treated patients undergoing coronary artery bypass graft surgery: the timing based on platelet function strategy to reduce clopidogrelassociated bleeding related to CABG (TARGET-CABG) study. Circ Cardiovasc Interv ;5: Kasivisvanathan R, Abbassi-Ghadi N, Kumar S et al. Risk of bleeding and adverse outcomes predicted by thromboelastography platelet mapping in patients taking clopidogrel within 7 days of non-cardiac surgery. Br J Surg 4;: Hobson AR, Agarwala RA, Swallow RA et al. Thrombelastography: current clinical 34

35 46. applications and its potential role in interventional cardiology. Platelets 6;7: Ferraris VA, Ferraris SP, Moliterno DJ et al. The Society of Thoracic Surgeons practice guideline series: aspirin and other antiplatelet agents during operative coronary revascularization (executive summary). Ann Thorac Surg 5;79: Lipets EN, Ataullakhanov FI. Global assays of hemostasis in the diagnostics of hypercoagulation and evaluation of thrombosis risk. Thromb J 5;3: Krzanicki D, Sugavanam A, Mallett S. Intraoperative hypercoagulability during liver transplantation as demonstrated by thromboelastography. Liver Transpl 3;9: Haemonetics Corporation. TEG, Haemonetics and Haemonetics The Blood Management Company are trademarks or registered trademarks of Haemonetics Corporation in the USA, other countries, or both. 4.5 Switzerland. COL-PP-3-IE(AA) Haemonetics (UK) Ltd Signy Centre, Rue des Fléchères 6 74 Signy-Centre Switzerland Haemonetics Corporation 4 Wood Road, Braintree, MA 84