Viscoelastic Monitoring Research Articles

Comparison of Citrated Whole Blood to Native Whole Blood for Coagulation Testing Using the Viscoelastic Coagulation Monitor (VCM Vet™) in Horses.

Viscoelastic monitoring of horse coagulation is increasing due to its advantages over traditional coagulation testing. The use of a point-of-care viscoelastic coagulation monitor (VCM Vet™) has been validated for use in horses using native whole blood (NWB) but has not been assessed using citrated whole blood (CWB), a technique that might have advantages in practicality and precision. Blood was collected from 70 horses, tested in duplicate immediately using NWB (T0), and stored at room temperature as CWB for testing in duplicate at 1 (T1) and 4 (T4) hours after venipuncture for comparison to NWB. Of these horses, 20 were classified as clinically healthy and used to determine reference intervals for CWB at 1 and 4 h post-collection. There were clinically relevant differences in all measured viscoelastic parameters of CWB compared to NWB meaning that they cannot be used interchangeably. These differences were not consistent at T1 and T4 meaning the resting time of CWB influences the results and should be kept consistent. The use of CWB in this study also resulted in more machine errors when compared to NWB resulting in measurements that might not be interpretable.

Feline aortic thromboembolism with and without congestive heart failure did not exhibit hypercoagulability using a novel viscoelastic coagulation monitor.

To demonstrate hypercoagulability with a benchtop viscoelastic monitor in cats with congestive heart failure (CHF) and/or aortic thromboembolism (ATE) compared to controls. 97 cats were enrolled throughout this prospective observational cohort study from September 2022 through October 2023. Cats were grouped by diagnosis of CHF, ATE, ATE plus CHF, or controls. Enrollment required diagnosis of heart disease and no previous antithrombotic therapy. The results of viscoelastic testing with the benchtop viscoelastic coagulation monitor (VCM Vet [VCM]; Entegrion) were compared between groups using factorial analysis of variance. Cats with heart disease had significantly higher clot times when compared to controls (control: mean, 285.3 [SD, 172.6]; CHF: mean, 391.7 [SD, 106.8]; ATE: mean, 415.9 [SD, 109.2]; and ATE plus CHF: mean, 368.6 [SD, 232.6]). Heart disease cats were noted to have significantly lower 45-minute lysis index values (control: median, 100 [range, 93 to 100]; CHF: median, 99 [range, 89 to 100]; ATE: median, 98 [range, 88 to 100]; and ATE plus CHF: range, 98 [91 to 100]). Age was a covariate to this variable, and when applied to analysis, statistical significance was lost. No significant difference in any other variables were noted. The hypercoagulability of ATE and CHF cats was not detected by the VCM. Further research with other coagulation monitors is required in this population.

Platelet hyperresponsiveness and increased platelet-neutrophil aggregates in dogs with myxomatous mitral valve disease and pulmonary hypertension.

Pulmonary hypertension (PH) in dogs with myxomatous mitral valve disease (MMVD) is caused by increased pulmonary venous pressure. Thrombosis, vascular remodeling, and vasoconstriction mediated by platelets could exacerbate PH. Dogs with PH will exhibit a hypercoagulable state, characterized by increased platelet activation, platelet-leukocyte, and platelet-neutrophil aggregate formation. Eleven dogs (≥3.5 kg) diagnosed with MMVD and PH and 10 dogs with MMVD lacking PH. Prospective cohort ex vivo study. All dogs underwent echocardiographic examination, CBC, 3-view thoracic radiographs, and heartworm antigen testing. Severity of PH and MMVD were assessed by echocardiography. Viscoelastic monitoring of coagulation was assessed using thromboelastography (TEG). Platelet activation and platelet-leukocyte/platelet-neutrophil interactions were assessed using flow cytometry. Plasma serotonin concentrations were measured by ELISA. Unstimulated platelets from dogs with MMVD and PH expressed more surface P-selectin than MMVD controls (P = .03). Platelets from dogs with MMVD and PH had persistent activation in response to agonists. The number of platelet-leukocyte aggregates was higher in dogs with MMVD and PH compared with MMVD controls (P = .01). Ex vivo stimulation of whole blood resulted in higher numbers of platelet-neutrophil aggregates in dogs with MMVD and PH (P = .01). Assessment of hypercoagulability based on TEG or plasma serotonin concentrations did not differ between groups. Platelet hyperresponsiveness and increased platelet-neutrophil interaction occur in dogs with MMVD and PH, suggesting that platelets play a role of in the pathogenesis of PH. Clinical benefits of antiplatelet drugs in dogs with MMVD and PH require further investigation.

Demonstration of hyperfibrinolysis on the VCM Vet in a dog with Angiostrongylus vasorum

AbstractThis case report details the clinical investigation of an 11‐month‐old, entire, male Cockapoo, who presented with acute left forebrain signs associated with suspected intra‐cranial haemorrhage due to Angiostrongylus vasorum. Initial investigations failed to identify a coagulopathy using traditional coagulation testing. Subsequent viscoelastic testing using the Viscoelastic Coagulation Monitor (VCM Vet, Entegrion) identified a hypocoagulable, hyperfibrinolytic trace. Anti‐fibrinolytic treatment with tranexamic acid showed improvement of hypocoagulability and normalisation of hyperfibrinolysis. Subsequent canine fresh frozen plasma transfusion and treatment of the underlying A. vasorum led to resolution of the patient's coagulopathy. This case report demonstrates the ease of use and utility of viscoelastic monitoring in global assessment of coagulation, and is the first case to document hyperfibrinolysis using the VCM Vet in a patient with Angiostrongylus vasorum.

Development and verification of a novel blood viscoelastic monitoring method based on reciprocating motion of magnetic bead.

Blood coagulation function is an essential index in clinical examination, and it is of great significance to evaluate blood coagulation function comprehensively. Based on the blood viscoelasticity theory and hydrodynamics, we proposed a method to monitor the whole blood coagulation process based on the reciprocating motion of the magnetic bead (magnetic bead method for short). We have established a mathematical model between the moment acting on the magnetic bead and the viscoelasticity of blood in the process of blood coagulation. The change of blood viscoelasticity acks on the magnetic bead in the form of moment changes, which shows that the amplitude of the motion of the magnetic bead varies with the change of blood viscoelasticity. Designed and verified a blood coagulation monitoring device based on the reciprocating movement of the magnetic bead and discussed the device's parameters through the orthogonal experiment. Lastly, the TEG5000 was used as the control group to test the thromboelasticity of four groups of thromboelastography quality control products in the same batch and 10 groups of human whole blood. It verified that our device has good repeatability, and has good consistency with TEG5000, it has particular application potential as a new blood coagulation monitoring method.

Viscoelastic Monitoring in Liver Transplantation.

Cirrhosis and liver transplantation (LT) surgery are associated with substantial alterations to the patient's coagulation status. Accurate monitoring of these changes during LT can help manage bleeding proactively and potentially reduce transfusion requirements. Unlike conventional coagulation tests (CCTs), viscoelastic monitoring (VEM) can provide an accurate, real-time, point-of-care assessment of coagulation status during LT and hence has become an invaluable tool for anesthetists and intensive care physicians. However, it remains an enigmatic subject for transplantation surgeons who are more conversant with CCTs. This review discusses the principles of VEM, provides a primer to understanding and interpreting its output, and explains how it can be used to make real-world clinical decisions during LT.

Perioperative Viscoelastic Assay Use for Monitoring Coagulation Among US Liver Transplantation Centers

Viscoelastic assay has been used in liver transplantation since 1985 and shown to be beneficial in detecting coagulopathy and to guide transfusion. The objective of this study was to review and evaluate the current uses of viscoelastic assay among US liver transplantation programs. Anesthesia program directors at all 137 liver transplantation centers in the United States were contacted via email and asked to complete a 21-item survey. The primary outcome measure was the percentage of viscoelastic assay used in the perioperative management of liver transplantation. Secondary outcome measures were institutional demographics, physician training level, and device demographics. Sixty-one of 137 (46%) centers responded. Liver transplantations were performed in the university setting at 48 of the 61 centers (77%), with a modal value of 11 to 50 liver transplantations a year and 74% in adult patients only. Most of the institutions (n=57, 92%) had access to either rotational thromboelastometry or thrombelastography during liver transplantation. Most centers (n=54; 87%) also used viscoelastic monitoring routinely (>60% of the time), including 42 (67.7%) that always used viscoelastic assay intraoperatively during liver transplantation. Thirty-five centers (59%) used it preoperatively, and 51 (84%) used it postoperatively. Most viscoelastic assay users (68%) learned how to use it through self-education and 10.5% learned during their fellowship or from a superuser or colleagues. Currently, viscoelastic monitoring is widely available and routinely used in most US liver transplantation centers regardless of university or private practice setting, but training in it is limited. Only 21.1% of respondents reported that they received any type of official training in viscoelastic assay interpretation.

Viscoelastic monitoring in trauma resuscitation.

Traumatic injury results in both physical and physiologic insult. Successful care of the trauma patient depends upon timely correction of both physical and biochemical injury. Trauma-induced coagulopathy is a derangement of hemostasis and thrombosis that develops rapidly and can be fatal if not corrected. Viscoelastic monitoring (VEM) assays have been developed to provide rapid, accurate, and relatively comprehensive depictions of an individual's coagulation profile. VEM are increasingly being integrated into trauma resuscitation guidelines to provide dynamic and individualized guidance to correct coagulopathy. We performed a narrative review of the search terms viscoelastic, thromboelastography, thromboelastometry, TEG, ROTEM, trauma, injury, resuscitation, and coagulopathy using PubMed. Particular focus was directed to articles describing algorithms for management of traumatic coagulopathy based on VEM assay parameters. Our search identified 16 papers with VEM-guided resuscitation strategies in adult patients based on TEG, 12 such protocols in adults based on ROTEM, 1 protocol for children based on TEG, and 2 protocols for children based on ROTEM. This review presents evidence to support VEM use to detect traumatic coagulopathy, discusses the role of VEM in trauma resuscitation, provides a summary of proposed treatment algorithms, and discusses pending questions in the field.

284EMF Thromboelastography to Assess Coagulopathy and Glycocalyx Degradation in Sepsis

Study Objectives: Sepsis is a common and deadly clinical syndrome that affects many patients presenting to the emergency department (ED) Sepsis-induced inflammation leads to abnormal coagulation Additionally, one potential mechanism for abnormal coagulation and organ dysfunction in sepsis is injury to the endothelial glycocalyx;the glycocalyx contains heparans which are released during degradation and may cause mild coagulopathy We hypothesize that coagulation abnormalities detected by bedside viscoelastic monitoring (VEM), such as thromboelastography, are associated with organ dysfunction and death (suggesting abnormal coagulation as a mediator) We further hypothesize that heparinase R-time, a VEM measurement that may detect glycocalyx degradation, will be associated with organ dysfunction Methods: Patients >18 years old with a diagnosis of sepsis were recruited from an urban ED (∼55,000 visits per year) as part of an ongoing observational study of a convenience sample of patients After informed consent was obtained, blood samples are to measure VEM VEM measurements include the R time, K time, alpha angle, maximum amplitude (MA), lysis percent at 30 minutes (LY30), and change in R time with the addition of heparinase (ΔR) We also collect demographic information, comorbidities, sepsis severity, the information necessary to determine the Sequential Organ Failure Assessment (SOFA) score, and mortality data We calculated descriptive statistics for VEM measurements, and Pearson correlations between VEM measurements and SOFA score on enrollment and on days 1-3 Results: We have enrolled 79 subjects thus far (study is ongoing) The baseline VEM parameters, expressed as median (IQR), are as follows: R, 5 3 minutes (4 2-6 4);K, 1 2 minutes (0 9-1 8);alpha angle, 72 0 degrees (65 7-75 8);MA, 68 3 millimeters (63 2-73 5);and LY30, 0 1 percent of maximum amplitude (0-1) The baseline ΔR is 0 4 minutes (IQR, 0 1-55) For patients enrolled to date, ΔR was correlated with day 1 SOFA score (r = -0 21, p < 0 03) Additionally, K was correlated with SOFA score on day 1 (0 22, p < 0 02) and day 2 (0 26, p < 0 03) Further results, delayed due to the impact of coronavirus on this project, will be available at the time of the Research Forum Conclusion: It is feasible to obtain VEM measurements in patients with sepsis Our ongoing work will recruit additional patients, measure syndecan-1 levels (a marker of glycocalyx degradation), determine illness severity scores (using Sequential Organ Failure Assessment scores) on days 0-3 and mortality outcomes, and determine whether syndecan-1 levels, VEM measurements, and patient outcome measurements are associated

Novel Treatment Strategy for Patients with Venom-Induced Consumptive Coagulopathy from a Pit Viper Bite

Pit viper venom commonly causes venom-induced consumptive coagulopathy (VICC), which can be complicated by life-threatening hemorrhage. VICC has a complex pathophysiology affecting multiple steps of the coagulation pathway. Early detection of VICC is challenging because conventional blood tests such as prothrombin time (PT) and activated partial thromboplastin time (aPTT) are unreliable for early-stage monitoring of VICC progress. As the effects on the coagulation cascade may differ, even in the same species, the traditional coagulation pathways cannot fully explain the mechanisms involved in VICC or may be too slow to have any clinical utility. Antivenom should be promptly administered to neutralize the lethal toxins, although its efficacy remains controversial. Transfusion, including fresh frozen plasma, cryoprecipitate, and specific clotting factors, has also been performed in patients with bleeding. The effectiveness of viscoelastic monitoring in the treatment of VICC remains poorly understood. The development of VICC can be clarified using thromboelastography (TEG), which shows the procoagulant and anticoagulant effects of snake venom. Therefore, we believe that TEG may be able to be used to guide hemostatic resuscitation in victims of VICC. Here, we aim to discuss the advantages of TEG by comparing it with traditional coagulation tests and propose potential treatment options for VICC.

How do I manage severe postpartum hemorrhage?

In the United States, postpartum hemorrhage (PPH) accounts for 4.6% of all maternal deaths and is responsible for major peripartum medical and surgical morbidity. Therefore, a national health priority is to ensure that women who experience severe PPH receive timely, appropriate, and effective treatment. In this article, we describe our system-wide approach for the planning and delivery of women with suspected placenta accreta spectrum disorder, a condition associated with life-threatening blood loss at the time of delivery. We also highlight current evidence related to transfusion decision making and hemostatic monitoring during active postpartum bleeding. Specifically, we describe how we activate and use the massive transfusion protocol to obtain sufficient volumes and types of blood products. We also describe how we use viscoelastic monitoring (thromboelastography) and standard laboratory tests to assess the maternal coagulation profile. Finally, we review the findings of recent studies examining the potential efficacy of tranexamic acid and fibrinogen concentrate as adjuncts for PPH prevention and treatment. We describe how we have incorporated these drugs into PPH treatment protocols at our institution.

A pilot study of viscoelastic monitoring in pediatric trauma: Outcomes and lessons learned

Background:Examine the characteristics and outcomes of pediatric trauma patients at risk for coagulopathy following implementation of viscoelastic monitoring.Materials and Methods:Injured children, aged <18 years, from September 7, 2014, to December 21, 2015, at risk for trauma-induced coagulopathy were identified from a single, level-1 American College of Surgeons verified pediatric trauma center. Patients were grouped by coagulation assessment: no assessment (NA), conventional coagulation testing alone (CCT), and conventional coagulation testing with rapid thromboelastography (rTEG). Coagulation assessment was provider preference with all monitoring options continuously available. Groups were compared and outcomes were evaluated including blood product utilization, Intensive Care Unit (ICU) utilization, duration of mechanical ventilation, and mortality.Results:A total of 155 patients were identified (NA = 78, CCT = 54, and rTEG = 23). There was no difference in age, gender, race, or mechanism. In practice, rTEG patients were more severely injured, more anemic, and received more blood products and crystalloid (P < 0.001). rTEG patients also had increased mortality with fewer ventilator and ICU-free days. Multivariate logistic regression and covariance analysis indicated that while rTEG use was not associated with mortality, it was associated with increased use of blood products, duration of mechanical ventilation, and ICU length of stay.Conclusions:Viscoelastic monitoring was infrequently performed, but utilized in more severely injured patients. Well-designed prospective studies in patients at high risk of coagulopathy are needed to evaluate goal-directed hemostatic resuscitation strategies in children.

Viscoelastic Monitoring to Guide Hemostatic Resuscitation in Liver Transplantation Surgery.

Coagulopathic bleeding must be anticipated during liver transplantation (LT) surgery. Patients with end-stage liver disease (ESLD) often present with disease-related hematologic disturbances, including the loss of hepatic procoagulant and anticoagulant clotting factors and thrombocytopenia. Transplantation surgery itself presents additional hemostatic changes, including hyperfibrinolysis. Viscoelastic monitoring (VEM) is often used to provide targeted, personalized hemostatic therapies for complex bleeding states including cardiac surgery and major trauma. The use in these coagulopathic conditions led to its application to LT, although the mechanisms of coagulopathy in these patients are quite different. While VEM is often used during transplant surgeries in Europe and North America, evidence supporting its use is limited to a few small clinical studies. The theoretical and clinical applications of the standard and specialized VEM assays are discussed in the setting of LT and ESLD.

Viscoelastic monitoring in pediatric trauma: a survey of pediatric trauma society members

BackgroundViscoelastic monitoring (VEM), including thromboelastography (TEG) and rotational thromboelastometry (ROTEM) in the setting of goal-directed hemostatic resuscitation has been shown to improve outcomes in adult trauma. The American College of Surgeons (ACS) Committee on Trauma recommends that “thromboelastography should be available at level I and level II trauma centers”. The purpose of this study is to determine the current availability and utilization of VEM in pediatric trauma. MethodsAfter IRB and Pediatric Trauma Society (PTS) approval, a survey was administered to the current members of the PTS via Survey Monkey. The survey collected demographic information, hospital and trauma program type, volume of trauma admissions, and use and/or availability of VEM for pediatric trauma patients. ResultsWe received 107 responses representing 77 unique hospitals. Survey respondents were: 61% physicians, 29% nurses, 6% trauma program managers, and 4% nurse practitioners/physician assistants. Over half of providers worked in a free standing children's hospital. Seventy-seven percent of respondents were from hospitals that had >200 trauma admissions/year, 42% were providers at ACS level 1 pediatric trauma centers, and 62% practiced at state level 1 designated centers. VEM was available to 63% of providers, but only 31% employed VEM in pediatric trauma patients. For those who had no VEM available, over 73% would utilize this technology if it was available. Seventy-one percent of providers continue to rely on conventional coagulation assays to monitor coagulopathy in pediatric trauma patients after admission. ConclusionsWhile a growing body of evidence demonstrates the benefit of viscoelastic hemostatic assays in management of adult traumatic injuries, VEM during active resuscitation is infrequently used by pediatric trauma providers, even when the technology is readily available. This represents a timely and unique opportunity for quality improvement in pediatric trauma.

Viscoelastic Methods of Blood Clotting Assessment - A Multidisciplinary Review.

Viscoelastic methods (VEM) made available the bedside assessment of blood clotting. Unlike standard laboratory tests, the results are based on the whole blood coagulation and are available in real time at a much faster turnaround time. In combination with our new knowledge about pathophysiology of the trauma-induced coagulopathy, the goal-oriented treatment protocols have been recently proposed for the initial management of bleeding in trauma victims. Additionally, the utility of viscoelastic monitoring devices has been proved even outside this setting in cardiosurgical patients or those undergoing liver transplantation. Many other situations were described in literature showing the potential use of bedside analysis of coagulation for the management of bleeding or critically ill patients. In the near future, we may expect further improvement in current bedside diagnostic tools enabling not only the assessment of secondary hemostasis but also the platelet aggregation. More sensitive assays for new anticoagulants are underway. Aim of this review is to offer the reader a multidisciplinary overview of VEM and their potential use in anesthesiology and critical care.

Curing and Post-curing Viscoelastic Monitoring of an Epoxy Resin

An experimental setup has been developed for the monitoring of ultrasonic parameters during polymerization in the context of the monitoring of composite plate production. An analytical approach is proposed based on the modeling of the wave velocity fitted by a Weibull distribution and was investigated to validate this approach by the Debye series modeling (DSM). The monitoring of the cured epoxy is also performed after curing in order to study the thermal transformation compared with DSC measurements. As a result, an approximated frequency-temperature (f, T) model is proposed for attenuation and velocity frequency and temperature dispersions.

Examination of hemostatic parameters to detect hypercoagulability in dogs with severe protein‐losing nephropathy

To identify hemostatic abnormalities in dogs with protein-losing nephropathies (PLN) that represent risk factors for pathologic thrombosis. Cross-sectional observational study of client-owned dogs with PLN, nonprotein losing renal failure (RF), and systemic illness (SI) exclusive of primary renal disease. Urban University Referral Center. A total of 29 dogs (n=11 PLN, n=7 RF, n=11 SI) were enrolled between January 2001 and July 2002. Samples were also collected from 20 clinically normal dogs to serve as hemostasis assay controls. None. HEMOSTASIS TESTING: Citrate anticoagulated blood was collected for point-of-care testing with a viscoelastic monitor (thromboelastograph [TEG]) and citrate plasma was prepared for coagulation screening tests and specific assay of the following hemostatic proteins: antiplasmin, antithrombin, D-dimer, Factor VIII, fibrinogen, plasminogen, protein C, and von Willebrand factor. Dogs with PLN and RF demonstrated TEG abnormalities consistent with hypercoagulability (eg, short clotting time, high clot amplitude) and both groups had significantly lower antithrombin than the SI group. The PLN dogs had significantly higher protein C than either the RF or SI group. Hyperfibrinogenemia was a consistent finding among all 3 disease groups, and the coagulation index a measure of hypercoagulability derived from TEG parameters, directly correlated with fibrinogen values of all study dogs. Hemostatic abnormalities consistent with systemic hypercoagulability are common in dogs with RF and PLN, however, no prothrombotic factors unique to PLN were identified in our study. The thrombotic tendency of PLN may therefore involve parameters we did not directly assess such as platelet reactivity, fibrinolysis, perturbations in blood flow, and/or endothelial dysfunction. High protein C is a novel finding in PLN dogs of unknown clinical relevance.

Viscoelastic monitoring of starch-based biomaterials in simulated physiological conditions

Dynamic mechanical analysis (DMA) was used to investigate the solid-state rheological behaviour in a starch-based thermoplastic aimed to be used in different biomedical applications. The tested samples were processed by different injection moulding procedures. The dry samples were immersed in a simulated physiological solution and the relevant viscoelastic parameters were monitored against time. The decrease of stiffness due to swelling can be followed in real time, being less pronounced for the composite sample with hydroxyapatite (HA). The temperature control of the liquid bath was found to be very good. Frequency scans were also performed in wet conditions in samples previously immersed during different times, indicating that DMA is a suitable method to control in-vitro the changes on the viscoelastic properties of biomaterials during degradation.

Effects of Ultrafiltration on Enoxaparin: An In Vitro Analysis

The use of low molecular weight heparins (LMWH) as an anticoagulant in the heparin-resistant patient poses challenges during cardiopulmonary bypass (CPB). The ultrafiltrability of LMWH has not been previously examined. The purpose of this study was to determine the effects of continuous ultrafiltration on the concentraton of a LMWH, enoxaparin. An in vitro analysis was performed using fresh whole human blood and an extracorporeal circuit containing four parallel ultrafiltrators and a cardiotomy reservoir with an integrated heat exchanger. Constant conditions included temperature (37°C), flow (0.20 L-min−1) transmembrane pressure (200 mmHg), and hematocrit (25 ± 2%). Samples were collected at the inlet, outlet, and ultrafiltrate line at one and three min for one control trial and again for each of the four hemoconcentrators following the bolus of enoxaparin. Coagulation measurements included a viscoelastic monitor (TEG), activated clotting time (ACT), activated partial thromboplastin time (aPTT), and quantitative analysis utilizing a membrane-based electrode for potentiometric measurement of polyanionic concentrations of enoxaparin. Enoxaparin concentration, from inlet to outlet, increased from 2.95 ± 0.64 to 5.89 ± 0.95 (p &lt; .001) at 1 min and 4.24 ± 0.49 to 7.89 ± 0.606 (p &lt; .001) at 3 min. Kinetic clot activity, as assessed by the TEG index, decreased from −3.8 ± 2.5 vs. −10.5 ± 6.0; (p &lt; .01) pre- to postultrafiltrator samples after 3 min. ACT and aPTT results demonstrated no significant change. In conclusions, this study demonstrates enoxaparin is concentrated with the use of continuous ultrafiltration. Functional coagulation studies also indicate a concentrating effect, primarily via the TEG.

Hemostatic Assessment of Patients Undergoing lntraaortic Balloon Pump Therapy

Patients undergoing intraaortic balloon pump (IABP) therapy are at risk for developing coagulopathies due to the adverse effects of prolonged exposure of the synthetic surface of the polyurethane balloon to blood components. Hemorrhagic risk has been attributed to a number of factors including thrombocytopenia, vascular injury, and/or platelet degranulation which increase the potential of receiving autogeneic blood transfusions. The present study is a prospective evaluation of coagulation using a viscoelastic monitor (Thrombelastograph- TEG) that measures functional aspects of clot development and stabilization in patients being treated with IABP therapy. Following Institutional Review Board approval, six patients undergoing IABP therapy for hemodynamic instability were enrolled in this study. Blood samples were taken prior to balloon insertion, at 8, 16, 24, 48, 72, and 96 hours on IABP therapy, and 24 hours following the removal of the balloon when applicable. Samples were incubated with heparinase to degrade heparin and TEG profiles were subsequently determined in duplicate. Measured parameters on the TEG included Rtime, K-time, maximum amplitude, alpha angle, and lysis at 30 and 60 minutes with calculation of the TEG index. Mortality was 33% following IABP discontinuation. Transfusion of packed red blood cells occurred in 50% of the patients during their balloon pump therapy. Patients demonstrated a significant deviance in fibrinolytic potential from pre-IABP lysis (1.6% ± 1.8) at both 24 hours (18.8% ± 22.9) and 48 hours (21.9% ± 28.5) of therapy (p&lt;0.05) which returned to baseline shortly after balloon removal. Activation of coagulation factors appeared evident by a steadily increasing alpha angle from pre-IABP data (31.1 ± 9.2) throughout the duration of therapy and 24 hour recovery (53 ± 14; p&lt;.005), and by a steadily trending increase in the TEG index pre-IABP (.251 ± 1.4) to post-IABP (2.6 ± 1.7; p&lt;0.05). The results indicate that IABP therapy induces an increase in fibrinolytic potential at 24 to 48 hours of balloon pump therapy with a paradoxical trend toward increased coagulability, potentially predisposing the patient to hemorrhagic risk.