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Introduction:
There are several clinical settings and patient conditions especially in intensive care units, emergency departments, and operating theaters, where the coagulation status of a patient must be known immediately and point-of-care (POC) systems are beneficial due to low time to result.
Methods:
This noninterventional, single-blinded,...
Context in source publication
Citations
... Specifically, the assays include prothrombin and partial thromboplastin time, platelet function assays, and various viscoelastic tests. The assays can be performed as point-of-care in clinical settings [2][3][4] where timely assessment is needed in the emergency department, surgery, trauma involving hemorrhagic shock, and more recently, COVID-19associated coagulopathy [5]. They can determine the patient's hemostatic competence more precisely but other critical factors that control hemostasis in the body may be omitted. ...
... There is a minimal intravascular hemostatic plug formed which is smaller than one observed in their in vivo mouse model [25]. (2) The pneumatic valve model does not have pre-coated TF. Nevertheless, the model achieves hemostasis with fibrin formation. ...
Currently, point-of-care assays for human platelet function and coagulation are used to assess bleeding risks and drug testing, but they lack intact endothelium, a critical component of the human vascular system. Within these assays, the assessment of bleeding risk is typically indicated by the lack of or reduced platelet function and coagulation without true evaluation of hemostasis. Hemostasis is defined as the cessation of bleeding. Additionally, animal models of hemostasis also, by definition, lack human endothelium, which may limit their clinical relevance. This review discusses the current state-of-the-art of hemostasis-on-a-chip, specifically, human cell-based microfluidic models that incorporate endothelial cells, which function as physiologically relevant in vitro models of bleeding. These assays recapitulate the entire process of vascular injury, bleeding, and hemostasis, and provide real-time, direct observation, thereby serving as research-enabling tools that enhance our understanding of hemostasis and also as novel drug discovery platforms.
... ABO blood groups are valuable in the studies of universal genetic to resolution medical, and a immunologic safety of blood during a transfusion. 29 Activated partial Thromboplastin (APTT), and Prothrombin Tim (PT) tests are commonly performed to screen coagulation factor deficiencies to give a considerate the coagulation status of individuals. 30 the variation in ABO blood group Antigen affects the intrinsic and extrinsic pathway of coagulation factors. ...
Background: Variances in blood group antigen have been related with susceptibility
particular to diseases. Prothrombin time [PT], measures the efciency of the extrinsic and
common coagulation pathways, although Activated partial Thromboplastin time [APTT] test evaluates the intrinsic and common coagulation pathways.
Objective: To explore the influence of blood groups antigen on APTT and PT among Healthy University Students on different ABO blood groups.
Materials and methods: Cross section study including student during the period of three
months from September 2020 to December 2020 at Medical campus, University of El Imam El Mahdi, White Nile State, Kosti City, total of 480 students were enrolled. Four milliliters of venous blood was collected from each student, ABO blood grouping was done by the tile method whereas APTT, and PT were analyzed using the manual methods. Data were processed using the Statistical Package for the Social Sciences (SPSS) program version 26 by means of descriptive and inferential statistics.
Results: Blood group O was largest among the test individuals [45%], followed by blood
group A [30%] and B [16%], while blood group AB has the smallest percentage of (9%).
Blood group O is signifcantly higher APTT value [39.07 ± 4.81] second compared to blood
groups A [36.60 ± 5.89] second, AB [35.23 ± 4.86] second, and B [34.39 ± 5.30] second,
P value < 0.05. Likewise, blood group A showed a signifcantly higher PT value [15.94 ± 1.36] second compared to blood groups O [14.12 ± 1.43] second, B [13.54 ± 1.35] second, and AB [14.67± 1.80] second, P < 0.05. Male had a higher APTT level (44.44± 7.27] second, PT [15.66 ± 1.88] second, and, compared with the female APTT [35.14 ± 6.49] second, PT [14.08 ± 1.29] second, P value < 0.05.
Conclusion: Males have a higher APTT and PT levels compared to females. Blood group
[O] individuals having a signifcantly higher APTT, while blood group [A]individuals having higher PT. This proposal that blood group of individuals may be affect their intrinsic (APTT) and extrinsic Coagulation mechanisms (PT].
... We investigated the comparison of a point-of-care version of the APTT to the lab-APTT assay and anti-Xa activity for monitoring UFH therapy in the ICU. To the best of our knowledge, this is the first longitudinal study evaluating the CoaguChek ® Pro II (Roche Diagnostics) with APTT reagent (CoaguCheck ® aPTT Test) in critically ill patients receiving UFH therapy Niederdöckl et al. first observed that the POC system showed reliable results for suspected coagulation factor deficiencies in a heterogeneous patient group [17]. Second, Arachchillage et al. evaluated this POCT device in 2019 on 80 ICU patients and suggested that the degree of anticoagulation in patients receiving UFH could not reliably be inferred from the POCT assay [4]. ...
... Niederdöckl et al. first observed that the POC system showed reliable results for suspected coagulation factor deficiencies in a heterogeneous patient group [17]. Second, Arachchillage et al. evaluated this POCT device in 2019 on 80 ICU patients and suggested that the degree of anticoagulation in patients receiving UFH could not reliably be inferred from the POCT assay [4]. ...
Continuous intravenous unfractionated heparin (UFH) is administered routinely in the intensive care unit (ICU) for the anticoagulation of patients, and monitoring is performed by the activated partial thromboplastin time (APTT) or anti-Xa activity. However, these strategies are associated with potentially large time intervals before dose adjustments, which could be detrimental to the patient. The aim of the study was to compare a point-of-care (POCT) version of the APTT to (i) laboratory-based APTT and (ii) measurements of anti-Xa activity in terms of correlation, agreement and turnaround time (TAT). Thirty-five ICU patients requiring UFH therapy were prospectively included and followed longitudinally for a maximum duration of 15 days. UFH was administered according to a local adaptation of Raschke and Amanzadeh’s aPTT nomograms. Simultaneous measurements of POCT-APTT (CoaguCheck® aPTT Test, Roche Diagnostics) on a drop of fresh whole blood, laboratory-based APTT (C.K. Prest®, Stago) and anti-Xa activity (STA®Liquid anti-Xa, Stago) were systematically performed two to six times a day. Antithrombin, C-reactive protein, fibrinogen, factor VIII and lupus anticoagulant were measured. The time tracking of sampling and analysis was recorded. The overall correlation between POCT-APTT and laboratory APTT (n = 795 pairs) was strongly positive (rs = 0.77, p < 0.0001), and between POCT-APTT and anti-Xa activity (n = 729 pairs) was weakly positive (rs = 0.46, p < 0.0001). Inter-method agreement (Cohen’s kappa (k)) between POCT and laboratory APTT was 0.27, and between POCT and anti-Xa activity was 0.30. The median TATs from sample collection to the lab delivery of results for lab-APTT and anti-Xa were 50.9 min (interquartile range (IQR), 38.4–69.1) and 66.3 min (IQR, 49.0–91.8), respectively, while the POCT delivered results in less than 5 min (p < 0.0001). Although the use of the POCT-APTT device significantly reduced the time to results, the results obtained were poorly consistent with those obtained by lab-APTT or anti-Xa activity, and therefore it should not be used with the nomograms developed for lab-APTT.
... Furthermore, the use of whole blood PT and aPTT significantly reduced the incidence of postoperative bleeding, transfusion of blood products and operative time [99]. They are useful in critical care, nonsurgical and emergency setting and provide reliable results [100]. However, high variability in POC PT and laboratory PT after protamine reversal in cardiac surgery, with clinically relevant discrepancy and underestimation of coagulopathy, is reported. ...
The concept of intensive care units (ICU) has existed for almost 70 years, with outstanding development progress in the last decades. Multidisciplinary care of critically ill patients has become an integral part of every modern health care system, ensuing improved care and reduced mortality. Early recognition of severe medical and surgical illnesses, advanced prehospital care and organized immediate care in trauma centres led to a rise of ICU patients. Due to the underlying disease and its need for complex mechanical support for monitoring and treatment, it is often necessary to facilitate bed-side diagnostics. Immediate diagnostics are essential for a successful treatment of life threatening conditions, early recognition of complications and good quality of care. Management of ICU patients is incomprehensible without continuous and sophisticated monitoring, bedside ultrasonography, diverse radiologic diagnostics, blood gas analysis, coagulation and blood management, laboratory and other point-of-care (POC) diagnostic modalities. Moreover, in the time of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, particular attention is given to the POC diagnostic techniques due to additional concerns related to the risk of infection transmission, patient and healthcare workers safety and potential adverse events due to patient relocation. This review summarizes the most actual information on possible diagnostic modalities in critical care, with a special focus on the importance of point-of-care approach in the laboratory monitoring and imaging procedures.
... In the ICU, point-of-care (POC) devices are beneficial due to fast and on-site results. In previous studies, POC aPTTs showed concordance with the laboratory aPTT [21][22][23]. ...
Background
Controlled anticoagulation is key to maintaining continuous blood filtration therapies. Objective: The study aimed to compare different blood sampling sites for activated partial thromboplastin time (aPTT) to evaluate anticoagulation with unfractionated heparin (UFH) in continuous renal replacement therapy (CRRT) and identify the most appropriate sampling site for safe patient anticoagulation and increased filter life span.
Method
The study was a prospective observational single-centre investigation targeting intensive care unit (ICU) patients on CRRT using an anticoagulation protocol based on patient characteristics and a weight-based modified nomogram. Eighty-four patients were included in the study. Four sampling sites were assessed: heparin free central venous nondialysis catheter (CVC), an arterial line with heparinised flush (Artery), a circuit access line (Access), and a circuit return line (Postfilter). Blood was sampled from each of four different sites on every patient, four hours after the first heparin bolus. aPTT was determined using a rapid clot detector, point of care device.
Results
A high positive correlation was obtained for aPTT values between CVC and Access sampling sites (r (84) =0.72; p <0 .05) and a low positive correlation between CVC and Arterial sampling site (r (84) =0.46, p < 0.05). When correlated by artery age, the young Artery (1-3 day old) correlates with CVC, Access and Postfilter (r (45) = 0.74, p >0.05). The aPTT values were significantly higher at Postfilter and Arterial sampling site, older than three days, compared to the CVC sampling site (p<0.05).
Conclusion
Considering patient bleeding risks and filter life span, the optimal sampling sites for safe assessment of unfractionated heparin anticoagulation on CRRT during CVVHDF were the central venous catheter using heparin free lavage saline solution, a heparinised flushed arterial catheter not older than three days, and a circuit access line.
... The biggest appeal of POC devices is short measurement durations (25-45 min) compared to conventional coagulation tests (40-60 min). POC INR devices can also be used in pre-hospital emergency services to provide fast and reliable results for patients suspected of coagulation factor deficiencies (Niederdöckl et al., 2016). To perform the aforementioned coagulation tests, different technologies such as electrical impedance spectroscopy, micro/nanoelectromechanical (MEMS/NEMS) resonator based rheometers, optical and photoacoustic measurements, and microfluidic viscometers have been employed. ...
In recent years, blood coagulation monitoring has become crucial to diagnosing causes of hemorrhages, developing anticoagulant drugs, assessing bleeding risk in extensive surgery procedures and dialysis, and investigating the efficacy of hemostatic therapies. In this regard, advanced technologies such as microfluidics, fluorescent microscopy, electrochemical sensing, photoacoustic detection, and micro/nano electromechanical systems (MEMS/NEMS) have been employed to develop highly accurate, robust, and cost-effective point of care (POC) devices. These devices measure electrochemical, optical, and mechanical parameters of clotting blood. Which can be correlated to light transmission/scattering, electrical impedance, and viscoelastic properties. In this regard, this paper discusses the working principles of blood coagulation monitoring, physical and sensing parameters in different technologies. In addition, we discussed the recent progress in developing nanomaterials for blood coagulation detection and treatments which opens up new area of controlling and monitoring of coagulation at the same time in the future. Moreover, commercial products, future trends/challenges in blood coagulation monitoring including novel anticoagulant therapies, multiplexed sensing platforms, and the application of artificial intelligence in diagnosis and monitoring have been included.
... In contrast, POC PT/aPTT appears to be useful in the nonsurgical and emergency outpatient setting showing reliable results for patients with suspected deficiencies of coagulation factors or under warfarin therapy. 54,55 Fibrinogen For POC fibrinogen measurement, a dry reagent method (dry hematology) assessing thrombin-induced clot formation in an oscillating magnetic field has been described. 56 The DRIHEMATO system (A&T Corporation, Kanagawa, Japan) is a cartridge-based fibrinogen assay approved for clinical use in Japan. ...
Bleeding complications after cardiac surgery are common and are associated with increased morbidity and mortality. Their etiology is multifactorial, and treatment decisions are time sensitive. Point-of-care (POC) testing has an advantage over standard laboratory tests for faster turn-around times, and timely decision on coagulation intervention(s). The most common POC coagulation testing is the activated clotting time (ACT), used to monitor heparin therapy while on cardiopulmonary bypass. Viscoelastic coagulation tests including thromboelastometry (ROTEM) and thromboelastography (TEG) have been recommended for the treatment of postoperative bleeding after cardiac surgery because the ROTEM/TEG-guided treatment algorithms reduced the use of blood products. Other POC tests are commercially available, but there is sparse evidence for their routine use in cardiac surgery. These devices include heparin management systems, POC prothrombin time and activated partial thromboplastin time, POC fibrinogen assay, and whole blood platelet function tests. There are multiple confounding elements and conditions associated with cardiac surgery, which can significantly alter test results. Anemia and thrombocytopenia are regularly associated with deviations in many POC devices. In summary, POC coagulation testing allows for rapid clinical decisions in hematological interventions, and, when used in conjunction with a proper transfusion algorithm, may reduce blood product usage, and potentially complications associated with blood transfusion.
... The reliability of these POC devices was investigated in several studies, demonstrating a high correlation of POC results compared with the results of conventional assessment of INR 45-49 and aPTT. 49 No technical difficulties in rapid assessment of INR were observed and all results were normally achieved within 2 minutes. 46 The gain of time due to the fast measurements of POC devices is very significant (25-45 minutes) and represents one of their biggest advantages over standard laboratory testing. ...
... 45 To support on-site decision making, POC INR devices provide fast and reliable results for patients with suspected deficiencies of coagulation factors and are also feasible in prehospital emergency care. 47,49 Nonetheless, the CoaguChek is approved only to monitor the effect of vitamin K antagonists (e.g., phenprocoumon). As there are many unsought influencing factors in an acute bleeding situation like trauma, the results of the CoaguChek should be interpreted with caution. ...
Trauma remains one of the major causes of death and disability all over the world. Uncontrolled blood loss and trauma-induced coagulopathy represent preventable causes of trauma-related morbidity and mortality. Treatment may consist of allogeneic blood product transfusion at a fixed ratio or in an individualized goal-directed way based on point-of-care (POC) and routine laboratory measurements. Viscoelastic POC measurement of the developing clot in whole blood and POC platelet function testing allow rapid and tailored coagulation and transfusion treatment based on goal-directed, factor concentrate-based algorithms. The first studies have been published showing that this concept reduces the need for allogeneic blood transfusion and improves outcome. This review highlights the concept of goal-directed POC coagulation management in trauma patients, introduces a selection of POC devices, and presents algorithms which allow a reduction in allogeneic blood product transfusion and an improvement of trauma patient outcome.
Background Even on the best antimalarial treatments (injectable artesunate) African children with severe malaria have poor outcomes with most deaths occurring early in the course of hospital admission (<24hours). Lactic acidosis, largely due to impairment of the microcirculatory flow due to parasite sequestration, is a main risk factor for poor outcome. There are no adjuvant treatments for severe malaria that target this complication. Sevuparin, a heparin-like drug, binds to Plasmodium falciparum erythrocyte membrane protein blocking merozoite invasion, preventing cytoadherence and transiently de-sequestering infected erythrocytes. Leading to improved microcirculatory flow by reversing/preventing parasite sequestration. If given early during admission this could result in improvements in outcomes . Sevuparin has been shown to be safe and well tolerated in adults with only some mild transient effects on activated partial thromboplastin time (APTT) were reported, without clinical consequences. Methods A Phase I trial designed to provide data on safety, dosing, feasibility of sevuparin as an adjuvant therapy in Kenya and Zambian children with severe malaria complicated by lactic acidosis (> 2mmol/l). Three intravenous doses will be given at admission (0 hours), 8 and 16 hours. APPT will be measured 1 hour after each dose (to assess maximum toxicity). Studying 20 children will allow sufficient data on safety to be generated across a range of doses to identify the maximum tolerated dose (MTD) using the Continual Reassessment Method, which adapts or informs subsequent doses for each child based on the data from previously enrolled children. The MTD will be identified based on the dose-toxicity model updated by each previous patient’s APTT results using standard methods. Conclusions The results of the Phase I trial will identify the final dose to be tested in a Phase II trial in terms of both efficacy and safety outcomes. Registration PACTR number: 202007890194806 (date 20/07/2020) ISRCTN32271864 (date 28/07/2021)
