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Entry

The Application of Viscoelastic Testing in Patient Blood Management

by
Mordechai Hershkop
,
Behnam Rafiee
and
Mark T. Friedman
*
NYU Grossman Long Island School of Medicine, NYU Langone Health, 259 First Street, Mineola, NY 11501, USA
*
Author to whom correspondence should be addressed.
Encyclopedia 2025, 5(3), 110; https://doi.org/10.3390/encyclopedia5030110
Submission received: 28 March 2025 / Revised: 26 June 2025 / Accepted: 29 July 2025 / Published: 31 July 2025
(This article belongs to the Section Medicine & Pharmacology)
Browse Figure
Review Reports Versions Notes

Definition

Patient blood management (PBM) is a multidisciplinary approach aimed at improving patient outcomes through targeted anemia treatment that minimizes allogeneic blood transfusions, employs blood conservation techniques, and avoids inappropriate use of blood product transfusions. Viscoelastic testing (VET) techniques, such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM), have led to significant advancements in PBM. These techniques offer real-time whole-blood assessment of hemostatic function. This provides the clinician with a more complete hemostasis perspective compared to that provided by conventional coagulation tests (CCTs), such as the prothrombin time (PT) and the activated partial thromboplastin time (aPTT), which only assess plasma-based coagulation. VET does this by mapping the complex processes of clot formation, stability, and breakdown (i.e., fibrinolysis). As a result of real-time whole-blood coagulation assessment during hemorrhage, hemostasis can be achieved through targeted transfusion therapy. This approach helps fulfill an objective of PBM by helping to reduce unnecessary transfusions. However, challenges remain that limit broader adoption of VET, particularly in hospital settings. Of these, standardization and the high cost of the devices are those that are faced the most. This discussion highlights the potential of VET application in PBM to guide blood-clotting therapies and improve outcomes in patients with coagulopathies from various causes that result in hemorrhage. Another aim of this discussion is to highlight the limitations of implementing these technologies so that appropriate measures can be taken toward their wider integration into clinical use.

1. Introduction

The World Health Organization (WHO) notes that PBM is a patient-centered approach that addresses anemia, coagulopathy, and blood loss in both surgical and nonsurgical patients as risk factors for adverse medical outcomes. Furthermore, the WHO includes minimization of blood loss and optimization of coagulation as one of three PBM pillars (along with detection and management of anemia and iron deficiency and leveraging and optimizing patient-specific physiological tolerance of anemia as the other two pillars) [1]. While timely blood transfusions certainly can be life-saving, unnecessary or excessive transfusions, which occur due to outdated clinical practices (e.g., transfusion of two units of red blood cells [RBCs] when a single unit would be sufficient), lack of clinical education in the use of blood products, and the use of outdated transfusion indication guidelines, among other contributing factors, increase risks to patients. Risks include volume overload (i.e., transfusion-associated circulatory overload [TACO]), immunological reactions (e.g., alloimmunization, hemolytic transfusion reactions, transfusion-related acute lung injury [TRALI]), transmissible diseases (e.g., viral hepatitis [hepatitis B virus, hepatitis C virus], human immunodeficiency virus [HIV], parasites [such as babesiosis and malaria]), allergic reactions, iron overload (i.e., excessive transfusion of RBCs), and transfusion-associated graft-versus-host disease (TA-GVHD).
VET represents a significant development in coagulation evaluation, offering dynamic, real-time assessment of clot formation, stability, and breakdown (fibrinolysis) [2,3]. Whereas CCTs, such as the PT and aPTT, among others, are performed using only the plasma portion of blood, VET analyzes whole-blood (WB) clot formation, enabling the clinician to understand the interaction of plasma coagulation factors with cellular blood components (i.e., RBCs and platelets) under conditions similar to physiological ones [4,5]. Although VET technologies were developed as early as 1948 with the invention of thromboelastography (TEG) by Hartert, they remained largely underutilized until the 1980s when improvements in device reliability and accessibility led to their broader adoption in clinical patient care [3,6]. Nevertheless, even in the present time, many institutions outside of major academic centers do not have VET analyzers [5].
VET has a wide range of utilities encompassing various clinical conditions [5]. The technology has revolutionized transfusion management in cardiac and liver transplantation surgery by minimizing the unnecessary use of blood products, thereby avoiding related complications [7,8,9]. In trauma, it may make the identification and correction of coagulopathies more efficient, potentially improving survival [10,11]. In obstetrics, it provides critical insights into hypercoagulable states during pregnancy and may aid in the management of severe postpartum hemorrhage [12,13,14]. Additionally, its use in oncology and critical care has allowed for individualized therapies in heterogeneous patient populations [15].
Nevertheless, there are several controversies concerning this modality. The main issues are the cost-effectiveness of VET compared to CCTs and the standardization of devices and protocols [16]. Several studies challenge the generalizability of findings from different clinical settings and patient groups. However, consensus emphasizes its revolutionary role in improving patient outcomes and healthcare spending.
This entry collates current evidence regarding VET, its utility in the clinical environment by discipline, its limitations, and points to future possibilities. The critical analysis is meant to guide the integration of VET into the broader patient management strategies. The main conclusion is that, although challenges remain, the adoption of VET represents an essential shift in hemostasis diagnostics and management [4]. Hence, better-targeted therapies and improved patient outcomes are in prospect as adaptation becomes more widespread.

2. Comparing VET and CCTs

One major consideration when choosing between CCTs and VET is turnaround time. CCTs require plasma separation through centrifugation. Then, thromboplastin reagent (PT) or phospholipid/activator (aPTT) and calcium (to reverse citrate anticoagulant) are added to the sample. A photometric or mechanical endpoint is recorded once fibrin formation reaches a fixed threshold [3,4]. This process takes 30 to 45 min for result reporting. VET, by contrast, does not need sample centrifugation since testing is performed on WB, saving time, with initial result reporting within 15 min [3,5]. Older VET test systems (TEG® 5000 [Haemonetics Corp., Braintree, MA, USA], ROTEM® [Werfen, Bedford, MA, USA]), which operated through a pin and cup mechanism (i.e., measuring mechanical resistance by a pin as WB solidifies to form a clot), incurred some delay due to the necessity of pipetting the WB sample into the cup (or cuvette). Newer systems (TEG® 6s, ROTEM® delta, Quantra® QPlus® and QStat® [Hemo-Sonics, Charlottesville, VA, USA]), however, do not require sample pipetting to the same extent, as they employ a cartridge-based test system, replacing the pin and cup mechanism. Table 1 shows a comparison of VETs vs. CCTs.
Due to its real-time and comprehensive analysis, VET is particularly useful in trauma resuscitation, cardiac surgery, obstetrics, liver transplantation, hematology and oncology, critical care, and pediatrics, where rapid and targeted intervention is often necessary [8,14,17]. However, higher costs and standardization issues currently limit its broader implementation [16].

3. VET Analyzers and Basic VET Patterns and Interpretation

VET analyzers commonly used include TEG, ROTEM, and the Quantra system [3]. While all three systems measure clot formation, stabilization, and dissolution in real time using citrate anticoagulated WB samples, there are important differences to be aware of. For example, TEG and Quantra use kaolin as the major activator of the intrinsic coagulation pathway in their test system (Citrated Kaolin [CK] in TEG), while ROTEM uses ellagic acid (INTEM) [3]. Both TEG and ROTEM offer testing with tissue factor (Citrated Rapid TEG [CRT] and EXTEM, respectively) for extrinsic coagulation pathway testing. Quantra uses sonic estimation of elasticity via resonance (SEER) ultrasound technology to measure clot formation [18,19]. All three systems can differentiate the fibrinogen contribution to clot formation through platelet inhibition via abciximab in TEG and Quantra, and cytochalasin in ROTEM (Citrated Functional Fibrinogen [CFF] in TEG; FIBTEM in ROTEM; Fibrinogen Contribution to Clot Stiffness [FCS] in Quantra) and offer testing of heparin anticoagulation through heparin neutralization (Citrated Kaolin Heparinase [CKH; TEG], HEPTEM [ROTEM], and Clot Time with Heparinase [CTH; Quantra]) [3]. TEG also offers specialized platelet function testing through its Platelet Mapping feature via heparin–anticoagulant samples and addition of arachidonic acid (AA) and adenosine diphosphate (ADP) agonists [3]. Comparison of hemostasis between the three analyzers has shown strong correlation in trauma and in surgical patients [18,19,20,21]. The TEG and ROTEM instruments translate the viscoelastic signal into a widening trace whose peak strength is labeled Maximum Amplitude (MA) in TEG and Maximum Clot Firmness (MCF) in ROTEM [3]. The measured parameters in each instrument are given in Table 2, Table 3 and Table 4 and Figure 1.
Older models of TEG (TEG 5000) and ROTEM (ROTEM delta) involved pin and cup technology in which a small volume of patient’s blood sample is pipetted into a cuvette (i.e., cup) and the mechanical resistance is measured during clot formation as either the cuvette rotates around a pin (TEG) or as the pin rotates in the cuvette (ROTEM). Newer TEG and ROTEM platforms (TEG 6s and ROTEM sigma) are cartridge-based, replacing the pin and cup technology, which are subject to vibration interference, with resonance frequency clot detection. Due to less pipetting and sensitivity to vibration and temperature, the newer cartridge-based platforms are more amenable to point-of-care test (POCT) use (i.e., use at the patient’s bedside). Similarly, the Quantra system’s cartridge-based SEER technology is amenable to use at the patient’s bedside and has been reported to provide even faster turn-around times than either TEG or ROTEM [20,21].

4. General Limitations and Possible Solutions

Despite the apparent clinical benefits of VET, several challenges hinder its widespread adoption. A major barrier is the high cost of analyzers and reagents, which can strain the budget of resource-limited healthcare facilities. Although there is potential to offset the cost through reduced blood product use and improved length of stay, such benefits may not be realized due to a lack of clinical training in VET result interpretation, as well as a lack of adherence to VET-based transfusion algorithms [16]. Furthermore, since there are no universal standard levels and protocols, analyzer and assay variability, as well as operator experience, can all contribute to institutional variation in results, lowering reproducibility and reliability of VET results. In addition, although VET use is intended to be used as POCT, many institutions still maintain the VET analyzers within the laboratory (i.e., remote from the patient’s bedside), thus reducing its effectiveness as a POCT device and limiting transfusion decisions based on real-time hemostasis results [16].
To move from critique to action, two recent consensus-building efforts provided concrete models for harmonization. In trauma, a modified Delphi process was used with a consensus panel consisting of 13 members of an advisory board that led to a goal-directed TEG 6s algorithm standardizing the choice of reagent, sampling times, and thresholds for treatment initiation [22]. The panel’s final consensus after two rounds of questions listed the following five recommendation statements: 1. CK-Reaction (R) time > 10 min suggests that a coagulation factor imbalance may be contributing to coagulopathy; consider treatment with plasma at dose 15–30 mL/kg; 2. for CFF-MA < 14 mm, consider infusing 4–6 g of fibrinogen as either cryoprecipitate or fibrinogen concentrate; 3. a CRT-MA value < 50 mm suggests a deficiency of platelet contribution to clot formation when the CFF-MA is normal; consider treatment with 1–2 units of apheresis platelets; 4. A CK Lysis at 30 min (LY30) value of >2.6% suggests an increase in fibrinolysis; tranexamic acid administration should be considered; and 5. If bleeding persists, TEG assays should be repeated every 30–60 min.
In cardiovascular surgery, a systematic literature review was performed by a team of cardiothoracic surgeons, anesthesiologists, and critical care physicians totaling seven experts to provide input in the development of an algorithm for hemostatic management of bleeding patients undergoing cardiac surgery based on TEG results (including both TEG 5000 and 6s) [23]. Recommendations from this group included the following: 1. heparin reversal via protamine administration if there is at least a 1.25-fold difference between the CK-R and CKH-R times; 2. coagulation factor repletion with either prothrombin complex concentrate (PCC) or plasma based upon an elevated CK-R time, with increasing dose requirements for CK-R times of 10–12 min, 13–15 min, and >15 min; 3. platelet transfusion (1–2 units) and desmopressin (DDAVP 0.3 μg/kg) for decreased CRT-MA in the presence of normal CFF-MA; 4. fibrinogen replacement (cryoprecipitate, 1–2 g fibrinogen) for CFF-MA < 15 mm; 5. antifibrinolytics (i.e., tranexamic acid, epsilon aminocaproic acid) for LY30 > 30%; and 6. repeat TEG 6s at regular intervals for ongoing bleeding.
Based on these examples, we suggest that future protocols for VET require explicit recording of analyzer, cartridge, and assay types; define treatment thresholds based on percentile-based standard scores relative to internal quality control procedures; and integrate device-specific reference tables into electronic decision-support systems to minimize between-operator variability. There are also several ways to reduce cost, such as partnering with manufacturers to pay for the analyzer at low or no upfront cost and rolling the cost into per-cartridge pricing. Cost may also be reduced through the partnership of low-income hospitals with regional blood centers to unlock donation programs. Lastly, the higher price can be justified to leadership using data that shows that VET leads to lower product usage and ultimately less long-term expenses for the hospital. It is hoped that using measures like these will improve VET accessibility.

5. Clinical Applications of VET

In trauma, efficiency in the provision of care is lifesaving. Massive bleeding is challenging, and VET provides more rapid feedback about a patient’s hemostasis status, helping clinicians to act more decisively instead of broadly administering transfusions through the administration of massive transfusion protocol (MTP) packs (i.e., transfused RBCs, plasma, and platelet components in a 1:1:1 ratio or WB transfusion). Aside from the recommendations noted above, while there is some evidence that is supportive of the use of VET for the treatment and monitoring of trauma-induced coagulopathy, there is no gold standard among the three major devices (TEG 6s, ROTEM delta, and Quantra QStat); however, the evidence is not robust [11,22,24,25]. A recent large European trial across seven trauma centers failed to show improved overall survival at 24 h for TEG or ROTEM in comparison to CCT-based hemorrhage management, although subset analysis of severe traumatic brain injury did show a significant reduction in 28-day mortality in the VET group. The findings in these studies highlight the necessity for further research into identifying patient populations that might benefit most from VET integration [11].
During cardiac surgery, managing coagulation can be complex as there can be hypocoagulable (i.e., excessive bleeding) and hypercoagulable (i.e., excessive clotting/thrombosis) states. The complexity in coagulation during cardiac surgery is in part due to the extent of heparin anticoagulation necessary during the course of the surgical procedure. However, the use of high doses of heparin complicates maintaining homeostasis in the course of the coagulation cascade, especially with large amounts of blood that need to be perfused [7,26]. In addition, equipment that is utilized in cardiopulmonary bypass (CPB) results in the dysfunction of platelets, further complicating hemostasis. The interaction among heparin, dysfunctional platelets, and the body’s intrinsic coagulation machinery creates a delicate balance that is difficult to sustain without vigilant monitoring. Approximately 3% of patients experience severe coagulopathy, and major bleeding occurs in up to 11% of cases. Additionally, up to 95% of patients undergoing cardiac surgery receive blood transfusions, highlighting the critical role of coagulation management in surgical outcomes. Despite efforts to optimize hemostasis, 5% of patients require surgical re-exploration due to persistent bleeding [26,27,28]. VET has the potential to allow cardiothoracic surgeons to analyze hemostasis in real time, enabling the clinical team to adjust anticoagulants or administer clotting agents as needed. Nevertheless, aside from the guidelines noted above, studies have published mixed results on the benefits of TEG and ROTEM for cardiac surgery with some studies reporting reduced use of allogeneic blood and re-exploration rates while another study concluded that while routine use of VET did reduce RBC and platelet transfusions, it did not impact mortality or major morbidity except acute kidney injury [7,26,27,28].
Managing blood loss is a high priority for obstetrical teams. Pregnancy naturally creates a hypercoagulable state, thus increasing the risk of thrombotic events; yet obstetric bleeding still paradoxically remains the leading cause of maternal death, with severe postpartum hemorrhage (PPH) accounting for approximately 27% of maternal deaths globally [12,29,30]. Additionally, for high-risk pregnancies, including those involving preeclampsia or clotting disorders, VET may allow for early detection of coagulopathy and tailored transfusion management [12,14,29,30,31,32]. In this respect, the application of VET has reduced the number of emergency procedures, such as hysterectomies, and, at the same time, enhanced overall outcomes for mothers and infants alike [14,31]. Despite a number of studies promoting the use of TEG and ROTEM for PPH management, including guidance of fibrinogen replacement, the use of VET for PPH is not universally embraced by expert panels [12,13,14,29,30,31,32]. Yet, a very recent prospective observational study once again supported the validity of ROTEM-guided MTP management for the majority of obstetric patients regardless of the presence of comorbidities or pregnancy complications [29].
Patients undergoing liver transplantation present great challenges for optimal coagulation management, and there is marked institutional variability in the methods of coagulation management in this patient group [33,34]. Coagulopathy in end-stage liver disease is often multifactorial [33,34]. While CCTs cannot reflect rebalanced hemostasis, involving both procoagulant and anticoagulant hemostatic disturbances that may lead to either thrombotic or bleeding complications, VET (TEG and ROTEM) has been shown to improve hemostasis management in liver transplantation [33,34]. Yet while ROTEM-guided transfusion algorithm for the management of liver transplantation has shown benefit through reduction in allogeneic blood product use, lower rates of postoperative complications (i.e., lower rates of reoperation for bleeding, retransplantation and acute kidney injury), and cost savings, there have been mixed findings on the effect of length of stay and no survival advantage for ROTEM over CCTs [34].
Similarly to patients undergoing CPB surgery, patients on extracorporeal membrane oxygenation (ECMO) experience great disturbances in hemostasis and are typically maintained on high doses of heparin anticoagulation. While CCTs, including the aPTT, PT, and the activated clotting time (ACT), are commonly used to monitor hemostasis in ECMO patients, they do not reflect the complexity of ECMO hemostatic alterations [35]. Many ECMO centers do use TEG and ROTEM clinically, though there is no gold standard and no standardized anticoagulant management protocols [35]. There is some published evidence to show improved critical care outcomes, less mortality, and less retroperitoneal bleeding in TEG-managed ECMO patients, though the data is limited [35].
Cancer patients experience high rates of venous thromboembolism (VTE), which is associated with significant morbidity and mortality in this group of patients, with some estimates placing VTE as the second most common cause of death in cancer patients behind cancer progression [15,36,37]. Therefore, interest has focused on the use of VET (mainly TEG) to identify cancer patients, particularly in prostate, lung, and breast cancer, who are at the highest risk for VTE and who will need anticoagulant therapy [15,36,37]. In this regard, VET has shown promise, though the results should be considered preliminary and are by no means universally positive [15,36,37].
In critical care, VET has been applied to patients for diagnosing and managing sepsis-induced coagulopathy. Those promoting VET (TEG and ROTEM) use for patients with severe sepsis find that it is useful for hemostasis assessment in real time as there is progression from the early hypercoagulable state to the later hypocoagulable state associated with disseminated intravascular coagulation (DIC) and fibrinolysis [38,39]. Yet not all critical care specialists agree on the value of VET for sepsis-induced coagulopathy (SIC) with Iba et al. writing that VET’s ability to diagnose hyperfibrinolysis is not advantageous in SIC, though they agree that more research is needed to determine the clinical utility of VETs in the setting of severe sepsis [40].
Strategies used in neonates and children to treat acute perioperative or trauma bleeding are extrapolated from experience in adults [41]. Most experience with VET has been derived from adult patients, and although goal-directed hemorrhage management protocols based on VET certainly would be welcomed as beneficial in the pediatric population, clear thresholds remain poorly defined [41]. A major advantage of VETs over CCTs in the pediatric population is the much smaller sample volume needed for testing (in the range of 300–400 μL per cartridge; i.e., four assays on the TEG 6S) [41]. Pediatric reference ranges for VET analyzers have been evaluated, although published ranges are not quite comparable across different authors and must be carefully interpreted [41]. One common finding across different publications, though, was a shorter time to clot initiation (i.e., shorter R and CT in TEG and ROTEM, respectively) [41,42]. Some experience in the use of VETs comes from pediatric ECMO cases, whereby platelet dysfunction is a common abnormality identified by VET [43,44]. Other published experiences in the use of VETs include pediatric cardiac surgery and critically ill infants and children [45,46].

6. Conclusions

In the foreseeable future, a number of important objectives need to be given priority in order to advance VET integration in clinical practice. Foremost among them is the institution of universal guidelines for interpreting and using VET to promote institutional homogenization and wider adoption. Second, lowering equipment costs through manufacturer partnerships and donation programs will enable greater access to VET for hospitals worldwide, particularly in underprivileged areas. Third, formal integration into current medical guidelines is important to encourage routine use in PBM guidelines, particularly in instances where VET has proven to be effective in reducing blood product consumption and improving survival rates. Finally, ongoing technological advancements in VET, including automation and increased accuracy, will make VET more efficient and user-friendly, thus making integration into modern healthcare systems seamless. In essence, VET is more than just a diagnostic tool—it is a powerful ally in saving lives. With determination to solve affordability and standardization issues, it has the potential to transform healthcare. This technology ensures that patients receive more precise and timely care when most needed.

Author Contributions

Conceptualization, M.H., M.T.F. and B.R.; methodology, M.T.F., M.H. and B.R.; formal analysis, M.H., M.T.F. and B.R.; investigation, M.H., M.T.F. and B.R.; resources, M.T.F., M.H. and B.R.; data curation, M.H., M.T.F. and B.R.; writing—original draft preparation, M.H., M.T.F. and B.R.; writing—review and editing, M.H., B.R. and M.T.F.; visualization, M.H., M.T.F. and B.R.; supervision, M.T.F. and B.R.; project administration, M.T.F. and B.R. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Conflicts of Interest

The authors declare no conflicts of interest.

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Encyclopedia 05 00110 g001
Figure 1. TEG (left) and ROTEM (right) tracings. TEG: R: Reaction time; K: Kinetic time; α: Alpha angle; MA: Maximum amplitude; LY30: Clot lysis at 30 min. ROTEM: CT: Clotting time; CFT: Clot formation time; α: Alpha angle; MCF: Maximum clot firmness; ML: Maximum lysis.
Figure 1. TEG (left) and ROTEM (right) tracings. TEG: R: Reaction time; K: Kinetic time; α: Alpha angle; MA: Maximum amplitude; LY30: Clot lysis at 30 min. ROTEM: CT: Clotting time; CFT: Clot formation time; α: Alpha angle; MCF: Maximum clot firmness; ML: Maximum lysis.
Encyclopedia 05 00110 g001
Table 1. Key differences between VET and CCTs.
Table 1. Key differences between VET and CCTs.
FeatureViscoelastic TestingConventional Coagulation Tests
Sample typeCitrated whole-blood (no centrifugation)Citrated plasma (requires centrifugation)
Turnaround time (TAT)5–15 min30–45 min
Clotting analysisReal-time clot formation, stability, breakdownFibrin clot formation endpoint
Platelet functionPlatelet mapping feature (thromboelastography)Not assessed
Fibrinolysis testingClot lysis at 30 minNot assessed
Utility in massive bleedingMore useful due to quicker result TATLimited due to prolonged result TAT
Table 2. Interpretation of TEG results.
Table 2. Interpretation of TEG results.
TEG ParameterFunctionIncreased ResultDecreased Result
R
(Reaction Time)		Time to initial clot
formation		Clotting factor deficiency or
anticoagulants (i.e., heparin)		Hypercoagulability
K
(Kinetic Time)		Time to reach a certain clot strengthFibrinogen deficiencyHypercoagulability
α
(Alpha Angle)		Speed of fibrin buildup and cross-linkingHypercoagulabilityDecreased fibrinogen or platelets/
platelet dysfunction
MA
(Maximum Amplitude)		Maximum clot strengthHypercoagulabilityDecreased fibrinogen or platelets/platelet
dysfunction
LY30
(Clot Lysis at 30 Min)		Clot breakdownHyperfibrinolysisNot applicable
Table 3. Interpretation of ROTEM results.
Table 3. Interpretation of ROTEM results.
ROTEM ParameterFunctionIncreased ResultDecreased Result
CT
(Clotting Time)		Time to initial fibrin formationCoagulation–factor deficiency, anticoagulants Hypercoagulability
CFT
(Clot Formation Time)		Time for clot to reach fixed firmnessLow fibrinogen, platelet dysfunctionHypercoagulability
α AngleSpeed of fibrin build-up and crosslinkingHypercoagulabilityLow fibrinogen or platelets
MCF
(Maximum Clot Firmness)		Maximal clot strengthHypercoagulabilityLow fibrinogen or platelets
CLI30/ML
(Clot Lysis Index/Maximum Lysis)		Clot stability/% lysisNormal or inhibited fibrinolysisHyperfibrinolysis
Table 4. Interpretation of Quantra results.
Table 4. Interpretation of Quantra results.
Quantra ParameterFunctionIncreased ResultDecreased Result
CT
(Clot Time)		Time to clot initiationCoagulation–factor deficiency, anticoagulantsHypercoagulability
CS
(Clot Stiffness)		Overall clot strengthHypercoagulabilityHypocoagulability
FCS
(Fibrinogen Contribution to Clot Stiffness)		Fibrinogen contribution to
stiffness		HyperfibrinogenemiaHypofibrinogenemia
PCS
(Platelet Contribution to Clot Stiffness)		Platelet contribution to stiffnessThrombocytosis/
high platelet reactivity		Thrombocytopenia/
dysfunction
CSL
(Clot Stability to Lysis)		Reduction in clot stiffness that is due to fibrinolysisNormal or inhibited fibrinolysisHyperfibrinolysis
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Hershkop, M.; Rafiee, B.; Friedman, M.T. The Application of Viscoelastic Testing in Patient Blood Management. Encyclopedia 2025, 5, 110. https://doi.org/10.3390/encyclopedia5030110

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Hershkop M, Rafiee B, Friedman MT. The Application of Viscoelastic Testing in Patient Blood Management. Encyclopedia. 2025; 5(3):110. https://doi.org/10.3390/encyclopedia5030110

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Hershkop, Mordechai, Behnam Rafiee, and Mark T. Friedman. 2025. "The Application of Viscoelastic Testing in Patient Blood Management" Encyclopedia 5, no. 3: 110. https://doi.org/10.3390/encyclopedia5030110

APA Style

Hershkop, M., Rafiee, B., & Friedman, M. T. (2025). The Application of Viscoelastic Testing in Patient Blood Management. Encyclopedia, 5(3), 110. https://doi.org/10.3390/encyclopedia5030110

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