Viscoelastic coagulation test for liver transplantation

Coagulation and transfusion management in patients undergoing liver transplantation is challenging. Proper perioperative monitoring of hemostasis is essential to predict the risk of bleeding during surgery, to detect potential causes of hemorrhage in time, and to guide hemostatic therapy. The value of conventional coagulation test is questionable in the acute perioperative setting due to their long turnaround time and the inability to adequately reflect the complex changes in hemostasis in patients with liver disease. Viscoelastic coagulation tests provide simultaneous measurement of multiple aspects of whole-blood coagulation including plasmatic coagulation and fibrinolytic factors and inhibitors that reflect most aspects of hemostasis. Coagulation initiation, mechanical clot stability, and fibrinolysis can be estimated immediately using point-of-care techniques. Therefore, viscoelastic coagulation tests including ROTEM & TEG would be useful to guide patient blood management strategy during liver transplantation.

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The role of thromboelastometry in the assessment and treatment of coagulopathy in liver transplant patients

Einstein (São Paulo) ◽

10.1590/s1679-45082017md3903 ◽

2017 ◽

Vol 15 (2) ◽

pp. 243-246 ◽

Cited By ~ 2

Author(s):

Raffael Pereira Cezar Zamper ◽

Thiago Chaves Amorim ◽

Luiz Guilherme Villares da Costa ◽

Flávio Takaoka ◽

Ary Serpa Neto

Keyword(s):

Liver Transplantation ◽

Objective Assessment ◽

Turnaround Time ◽

Transfusion Therapy ◽

Static Tests ◽

Transplant Patients ◽

Perioperative Monitoring ◽

Assessment And Treatment ◽

Surgical Field ◽

Potential Improvement

ABSTRACT Perioperative monitoring of coagulation is vital to assess bleeding risks, diagnose deficiencies associated with hemorrhage, and guide hemostatic therapy in major surgical procedures, such as liver transplantation. Routine static tests demand long turnaround time and do not assess platelet function; they are determined on plasma at a standard temperature of 37°C; hence these tests are ill-suited for intraoperative use. In contrast, methods which evaluate the viscoelastic properties of whole blood, such as thromboelastogram and rotational thromboelastometry, provide rapid qualitative coagulation assessment and appropriate guidance for transfusion therapy. These are promising tools for the assessment and treatment of hyper- and hypocoagulable states associated with bleeding in liver transplantation. When combined with traditional tests and objective assessment of the surgical field, this information provides ideal guidance for transfusion strategies, with potential improvement of patient outcomes.

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Blood management in post-partum haemorrhage, including point of care coagulation tests

10.22514/sv.2021.030 ◽

2021 ◽

Keyword(s):

Early Recognition ◽

Point Of Care ◽

Post Partum ◽

Coagulation Factor ◽

Team Approach ◽

Blood Products ◽

Blood Management ◽

Coagulation Tests ◽

Haematological Changes ◽

The Uk

Postpartum haemorrhage (PPH) is the leading global cause of maternal mortality, and an important cause of morbidity and mortality in the UK. Management of PPH requires a patient centred team approach to ensure effective management. Early recognition is crucial, hence quantitative measurement of blood loss should be started as soon as bleeding is identified and continue throughout an evolving haemorrhage. Pregnancy is associated with haematological changes resulting in a pro-coagulant state. Blood management in PPH has moved away from the use of shock packs and fixed transfusion ratios. Most women are not initially coagulopathic and coagulopathy is uncommon in mild to moderate PPH, Practice has therefore moved towards goal directed transfusion of blood products informed by haematological investigations alongside clinical assessment. Fibrinogen tends to be the first coagulation factor to fall and Clauss fibrinogen is an important predictor of PPH severity. Transfusion of fibrinogen rich blood products such as cryoprecipitate and fibrinogen complex are more effective at rapidly increasing fibrinogen levels compared to FFP. Point of care (POC) coagulation tests such as rotational thromboelastometry (ROTEM) and thromboeslastography (TEG) allow rapid bedside assessment compared to traditional laboratory tests. Surrogate markers of fibrinogen from POC tests can be used to both predict severity of PPH and inform blood transfusion. There is growing evidence that POC coagulation tests can be used to safely guide blood management in PPH, with its use associated with lower transfusion rates and possibly improved clinical outcomes. Further multi-centre studies are required to clarify debate surrounding their use. In this review we discuss blood management in PPH, with a focus on recent evidence regarding assessment of coagulopathy and the use of blood products.

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The Utilization of Viscoelastic Testing to Guide Blood Component Therapy and Adjunctive Hemostatic Therapy for Postpartum Hemorrhage: A Narrative Review

Current Opinion in Gynecology and Obstetrics ◽

10.18314/cogo.v2i1.1837 ◽

2019 ◽

pp. 272-286

Author(s):

Baumgartner S ◽

Shariff F ◽

Vande Lune SA ◽

Zackariya N ◽

Grisoli A ◽

...

Keyword(s):

Postpartum Hemorrhage ◽

Point Of Care ◽

Narrative Review ◽

Blood Component ◽

Clinical Parameters ◽

Rotational Thromboelastometry ◽

Coagulation Tests ◽

Blood Component Therapy ◽

History Of ◽

Hemostatic Therapy

This narrative review discusses the history of the pathophysiologic principles and utilization of point-of-care (POC) viscoelastic tests (VETs) in the definition and treatment of postpartum hemorrhage (PPH). This paper addresses the epidemiology of PPH, describes the hemostatic changes that occur in pregnancy and in PPH, and demonstrates the utilization of viscoelastic testing in the identification and treatment of patients with PPH. Additionally, a description of rotational thromboelastometry (ROTEM) and thromboelastography (TEG), the two most commonly used VETs, is detailed in this paper. VETs have only recently been used to guide blood component therapy (BCT) in trauma in the last decade. The recent increased utilization of VETs to guide BCT in PPH is following a similar trend with a delay of ten years. In a similar fashion to the trauma literature, which expanded greatly within this last decade, the literature concerning the use of VETs in PPH has also increased in the last few years. However, because of differing pathophysiologies associated with the coagulopathy of PPH verses traumatic-induced coagulopathy (TIC), utilization of VETs has been more refined and focused on the VETs’ capacity to determine low fibrinogen and to guide the utilization of blood components and prohemostatic agents. The identification and treatment of PPH depends on clinical parameters, conventional coagulation tests (CCTs) including Clauss fibrinogen, and VETs. Successful treatment of PPH will no doubt include utilization of all three strategies with an increasing utilization of VETs in the future.

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The Effect of Platelet -, and Leukocyte Count on the Thrombelastograph® (TEG) Parameters.

Blood ◽

10.1182/blood.v104.11.3971.3971 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3971-3971

Author(s):

W.W.H. Roeloffzen ◽

J.C. Kluin-Nelemans ◽

Joost de Wolf

Keyword(s):

Platelet Count ◽

Point Of Care ◽

Maximum Amplitude ◽

Multiple Regression Model ◽

Clot Strength ◽

Normal Limits ◽

Coagulation Tests ◽

Plasmatic Coagulation ◽

Sensitivity Specificity ◽

Normal Controls

Abstract Background. The TEG is used in situations were point of care testing of hemostasis is desired, although its value is still controversially because of insufficient test validation. The main parameters of the TEG are (a) the reaction time (R), the time until the initial fibrin formation and comparable with the coagulation times PT and APTT; (b) clotting time (K), the time until a fixed level of clot firmness is reached; (c) the angle (α) is closely related to K and measures the rapidity of fibrin build up and gives information about the clot strength; R, K and α are prolonged by anticoagulants and factor deficiencies; (d) maximum amplitude (MA) is a measurement of maximum strength or stiffness of the developed clot; it is especially influenced by platelets and fibrin. Methods. We performed a multivariate analysis using the Cox multiple-regression model to study the effects of Leukocytes, Hb, and platelet count on the TEG parameters. Results. Ninety native whole blood samples from 19 patients undergoing consolidation chemotherapy were studied; in the post chemotherapy phase in which platelets decreased from normal to < 10 x 109/l samples were taken; in all these cases PT, APTT and Fibrinogen were within normal limits. Platelets significantly influenced all parameters: R (p<0.001, r=−0.5), K (p<0.001, r=−0.7), α (p<0.001, r=+0.7), MA (p<0.001, r=+0.6) whereas Leukocytes influenced MA as well (p<0.001, r=0.3). In normal controls K is 9 ± 3 min (n=110), in patients with platelet count 50–100, 25–50 and <25 x 109/l K was resp. 17 ± 9, 30 ± 13 and 46 ± 10 min. In normal controls MA was 46 ± 7 mm, in patients MA became significant smaller with platelets < 25 x 109/l: 30 ± 5 mm. In patients with leukocytes ranging from 0–0.1, 0.1–1.0, 1.0–3.5 and > 3.5 x 109/l the MA was resp. 44 ± 14, 49 ± 15, 54 ± 9, and 58 ± 8 mm. As the MA is considered the parameter most influenced by platelet count, we calculated the sensitivity, specificity, pos and neg predictive value of MA to detect a platelet count less then 50 x 109/l, they were resp. 35%, 100%, 100% and 73%. Conclusion. Firstly, platelet count not only influences MA but also the coagulation parameters R, K and α; besides leukocytes influences the clot strength; this is in agreement with the new conceptual cell based model of hemostasis; secondly, the TEG should be considered as additive to platelet count and plasmatic coagulation tests and not as a replacement.

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A data-driven patient blood management strategy in liver transplantation

Vox Sanguinis ◽

10.1111/vox.12650 ◽

2018 ◽

Vol 113 (5) ◽

pp. 421-429 ◽

Cited By ~ 4

Author(s):

R. A. Metcalf ◽

M. B. Pagano ◽

J. R. Hess ◽

J. Reyes ◽

J. D. Perkins ◽

...

Keyword(s):

Liver Transplantation ◽

Management Strategy ◽

Data Driven ◽

Patient Blood Management ◽

Blood Management

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Making sense of rapid antigen testing in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostics

Diagnosis ◽

10.1515/dx-2020-0131 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Camilla Mattiuzzi ◽

Brandon M. Henry ◽

Giuseppe Lippi

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Point Of Care ◽

Turnaround Time ◽

Molecular Testing ◽

Upper Respiratory Tract ◽

Making Sense ◽

Skilled Personnel ◽

Potential Benefits ◽

Antigen Testing ◽

Care Availability

AbstractAlthough the most effective strategy for preventing or containing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks relies on early diagnosis, the paramount and unprecedented number of tests needed to fully achieve this target is overwhelming worldwide testing supply and capacity. Molecular detection of SARS-CoV-2 RNA in nasopharyngeal swabs is still considered the reference diagnostic approach. Nonetheless, identification of SARS-CoV-2 proteins in upper respiratory tract specimens and/or saliva by means of rapid (antigen) immunoassays is emerging as a promising screening approach. These tests have some advantages compared to molecular analysis, such as point of care availability, no need of skilled personnel and dedicated instrumentation, lower costs and short turnaround time. However, these advantages are counterbalanced by lower diagnostic sensitivity compared to molecular testing, which would only enable to identifying patients with higher SARS-CoV-2 viral load. The evidence accumulated to-date has hence persuaded us to develop a tentative algorithm, which would magnify the potential benefits of rapid antigen testing in SARS-CoV-2 diagnostics.

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A 3D-printed magnetic digital microfluidic diagnostic platform for rapid colorimetric sensing of carbapenemase-producing Enterobacteriaceae

Microsystems & Nanoengineering ◽

10.1038/s41378-021-00276-9 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Pojchanun Kanitthamniyom ◽

Pei Yun Hon ◽

Aiwu Zhou ◽

Mohammad Yazid Abdad ◽

Zhi Yun Leow ◽

...

Keyword(s):

Point Of Care ◽

Resistance Mechanism ◽

Turnaround Time ◽

World Health ◽

Colorimetric Sensing ◽

Resource Limited ◽

Reaction Chambers ◽

Technological Platform ◽

Health Organization ◽

Digital Microfluidic

AbstractCarbapenemase-producing Enterobacteriaceae (CPE) are a group of drug-resistant Gram-negative pathogens that are classified as a critical threat by the World Health Organization (WHO). Conventional methods of detecting antibiotic-resistant pathogens do not assess the resistance mechanism and are often time-consuming and laborious. We have developed a magnetic digital microfluidic (MDM) platform, known as MDM Carba, for the identification of CPE by measuring their ability to hydrolyze carbapenem antibiotics. MDM Carba offers the ability to rapidly test CPE and reduce the amount of reagents used compared with conventional phenotypic testing. On the MDM Carba platform, tests are performed in droplets that function as reaction chambers, and fluidic operations are accomplished by manipulating these droplets with magnetic force. The simple droplet-based magnetic fluidic operation allows easy system automation and simplified hands-on operation. Because of the unique “power-free” operation of MDM technology, the MDM Carba platform can also be operated manually, showing great potential for point-of-care testing in resource-limited settings. We tested 27 bacterial isolates on the MDM Carba platform, and the results showed sensitivity and specificity that were comparable to those of the widely used Carba NP test. MDM Carba may shorten the overall turnaround time for CPE identification, thereby enabling more timely clinical decisions for better clinical outcomes. MDM Carba is a technological platform that can be further developed to improve diagnostics for other types of antibiotic resistance with minor modifications.

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COVID-19 Biomarkers and Advanced Sensing Technologies for Point-of-Care (POC) Diagnosis

Bioengineering ◽

10.3390/bioengineering8070098 ◽

2021 ◽

Vol 8 (7) ◽

pp. 98

Author(s):

Ernst Emmanuel Etienne ◽

Bharath Babu Nunna ◽

Niladri Talukder ◽

Yudong Wang ◽

Eon Soo Lee

Keyword(s):

Response Times ◽

Rna Virus ◽

Point Of Care ◽

Protein Detection ◽

Turnaround Time ◽

Quantitative Detection ◽

Rt Pcr ◽

Specificity And Sensitivity ◽

Small Market ◽

Multiple Biomarkers

COVID-19, also known as SARS-CoV-2 is a novel, respiratory virus currently plaguing humanity. Genetically, at its core, it is a single-strand positive-sense RNA virus. It is a beta-type Coronavirus and is distinct in its structure and binding mechanism compared to other types of coronaviruses. Testing for the virus remains a challenge due to the small market available for at-home detection. Currently, there are three main types of tests for biomarker detection: viral, antigen and antibody. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) remains the gold standard for viral testing. However, the lack of quantitative detection and turnaround time for results are drawbacks. This manuscript focuses on recent advances in COVID-19 detection that have lower limits of detection and faster response times than RT-PCR testing. The advancements in sensing platforms have amplified the detection levels and provided real-time results for SARS-CoV-2 spike protein detection with limits as low as 1 fg/mL in the Graphene Field Effect Transistor (FET) sensor. Additionally, using multiple biomarkers, detection levels can achieve a specificity and sensitivity level comparable to that of PCR testing. Proper biomarker selection coupled with nano sensing detection platforms are key in the widespread use of Point of Care (POC) diagnosis in COVID-19 detection.

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Evaluation of mobile real-time polymerase chain reaction tests for the detection of severe acute respiratory syndrome coronavirus 2

Scientific Reports ◽

10.1038/s41598-021-88625-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chukwunonso Onyilagha ◽

Henna Mistry ◽

Peter Marszal ◽

Mathieu Pinette ◽

Darwyn Kobasa ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Real Time ◽

Point Of Care ◽

Middle Eastern ◽

Turnaround Time ◽

Cross Reactivity ◽

Clinical Samples ◽

Diarrhea Virus ◽

Highly Sensitive ◽

Transmissible Gastroenteritis

AbstractThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), calls for prompt and accurate diagnosis and rapid turnaround time for test results to limit transmission. Here, we evaluated two independent molecular assays, the Biomeme SARS-CoV-2 test, and the Precision Biomonitoring TripleLock SARS-CoV-2 test on a field-deployable point-of-care real-time PCR instrument, Franklin three9, in combination with Biomeme M1 Sample Prep Cartridge Kit for RNA 2.0 (M1) manual extraction system for rapid, specific, and sensitive detection of SARS-COV-2 in cell culture, human, and animal clinical samples. The Biomeme SARS-CoV-2 assay, which simultaneously detects two viral targets, the orf1ab and S genes, and the Precision Biomonitoring TripleLock SARS-CoV-2 assay that targets the 5′ untranslated region (5′ UTR) and the envelope (E) gene of SARS-CoV-2 were highly sensitive and detected as low as 15 SARS-CoV-2 genome copies per reaction. In addition, the two assays were specific and showed no cross-reactivity with Middle Eastern respiratory syndrome coronavirus (MERS-CoV), infectious bronchitis virus (IBV), porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis (TGE) virus, and other common human respiratory viruses and bacterial pathogens. Also, both assays were highly reproducible across different operators and instruments. When used to test animal samples, both assays equally detected SARS-CoV-2 genetic materials in the swabs from SARS-CoV-2-infected hamsters. The M1 lysis buffer completely inactivated SARS-CoV-2 within 10 min at room temperature enabling safe handling of clinical samples. Collectively, these results show that the Biomeme and Precision Biomonitoring TripleLock SARS-CoV-2 mobile testing platforms could reliably and promptly detect SARS-CoV-2 in both human and animal clinical samples in approximately an hour and can be used in remote areas or health care settings not traditionally serviced by a microbiology laboratory.

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Requiem for the STAT Test: Automation and Point of Care Testing

Laboratory Medicine ◽

10.1093/labmed/lmz080 ◽

2019 ◽

Author(s):

Gurmukh Singh ◽

Natasha M Savage ◽

Brandy Gunsolus ◽

Kellie A Foss

Keyword(s):

Point Of Care ◽

Turnaround Time ◽

Test Automation ◽

Test Results ◽

Point Of Care Testing ◽

Tube System ◽

Front End ◽

Laboratory Test Results ◽

Batch Testing ◽

Pneumatic Tube System

Abstract Objective Quick turnaround of laboratory test results is needed for medical and administrative reasons. Historically, laboratory tests have been requested as routine or STAT. With a few exceptions, a total turnaround time of 90 minutes has been the usually acceptable turnaround time for STAT tests. Methods We implemented front-end automation and autoverification and eliminated batch testing for routine tests. We instituted on-site intraoperative testing for selected analytes and employed point of care (POC) testing judiciously. The pneumatic tube system for specimen transport was expanded. Results The in-laboratory turnaround time was reduced to 45 minutes for more than 90% of tests that could reasonably be ordered STAT. With rare exceptions, the laboratory no longer differentiates between routine and STAT testing. Having a single queue for all tests has improved the efficiency of the laboratory. Conclusion It has been recognized in manufacturing that batch processing and having multiple queues for products are inefficient. The same principles were applied to laboratory testing, which resulted in improvement in operational efficiency and elimination of STAT tests. We propose that the target for in-laboratory turnaround time for STAT tests, if not all tests, be 45 minutes or less for more than 90% of specimens.

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