Portable Device for Express Assessment of Functional State of Hemostasis System
Egor L. Zhukov1,2, Fedor A. Gubarev1, Ivan I. Tyutrin2
1Research School of Chemistry and Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
2”Mednord-Technics” LLC, Tomsk, Russia
This paper presents the development results of portable device for express assessment of functional state of hemostasis system. The vascular platelet hemostasis among healthy volunteers of the Siberian population was assessed in real-time mode. Research results from portable device were compared with the method of low-frequency piezothromboelastography (piezothromboelastograph ARP-01M “Mednord” 2010/09767). The received data presented high correlation.
The functional state ofhemostasis system has the greatest importance for normal blood circulation, prevention and reversal of hemorrhage, thrombosis, ischemia and infarction of organs, protection against bacteria and toxin dissemination from affected areas. That is the main biological meaning of hemostasis system and role of its disorder in the pathogenesis of disease [1 – 8]. The importance of hemostasis system research for general medical practice cannot be overemphasized it is an essential implement in the care of patients in a life-threatening state .
All the above-mentioned facts determine hemostasiological laboratory tests as highly important for medical practice. Special meaning of blood coagulation system control is connected with an active usage of modern highly effective direct/indirect effect anticoagulants, antiaggregants and thrombolytics in clinical practice. In this case the best therapeutic effect is achieved by purposive bleeding disorders correction .
Early treatment and complication prevention activities depend on fast and accurate diagnosis of bleeding disorders.
At present, there is a variety of conventional methods for hemostasis system investigation based on citrate venous blood assessment by long preanalytical phase [9,10], that is obstacle for accurate assessment of functional state of analyzed system and does not present the complete system view.
A detailed study of all hemostasis elements is laborious and time-consuming, requires large amounts of blood, it is not rapid and can be characterized as supplementary not exploring [1 – 5].
In connection with the «point-of-care test» trend and due to medicine personification there is more emphasis on «global» tests with operating/integrative assessment of plasmatic and cell constituents in native blood, involved into the full fibrinogenesis cycle (from the initiation/amplification till the cross-linked fibrin formation and its potential lysis) [2,11,12].
An essential accurate research condition can be reached through the significant time reduction in the preanalytical phase, which one has about 68% of all laboratory errors .
Common methods and devices determine clotting time with plasma [10 – 13], citrated blood [9 – 12] and native venous blood .
Obviously, obtaining venous blood samples includes the need for highly qualified personnel and special facilities. Obtaining capillary blood samples is less traumatizing and does not need special facilities.
According to above mentioned facts the developing of portable device for native capillary blood testing at the bedside of the patient and out of clinic is required.
Thus, the aim of proposed study is the developing of portable device for express assessment of functional state of hemostasis system by using native capillary blood, and the assessing of reference indices obtained by comparative analyze with method of piezothromboelastograph ARP-01M «Mednord».
The portable device developing included creation of disposable cartridge and receiving unit for data processing.
The main stages of the disposable cartridge developing were the selection of optimized sensor material, the resonant frequency of the sensor and the size of the measuring chamber for tasting required amount of analyte – the whole capillary blood.
As the sensor material was piezoceramics lead zirconate titanate selected due to its ability being applied with a required sized silver electrodes without damaging it. Piezoelement shape is quill cylinder covered with external electrode divided into two symmetric parts: generator and receiver of ultrasonic vibrations; the internal electrode is side of the measuring chamber. Shape and size of measuring chamber are shown in Fig.1.
Piezoceramics element size was determined according to needed samples volume — native capillary blood that is taken by standard scarifier: 20…25 μl. The required resonant frequency level 160±0.02% kHz is provided by optimized material and piezoceramics element selection.
The measuring chamber is placed on the electronic board which is the disposable cartridge base. In Fig.2 the disposable cartridge model is shown.
It was decided to connect disposable cartridge and portable device per standard USB port due to its reliability, ease of use and low cost. In addition, the USB port can be used to connect the device with PC.
For processing and interpretation of the test results with disposable cartridge obtained receiving device for “point-of-care” use was developed.
The device is implemented on the basis of the microcontroller, a ready to use solution from Arduino© was chosen . Basic device functions are provided by analog-to-digital converter built into the microcontroller.
Built-in battery allows using of portable device at the bedside of the patient or by the patient out of clinic.
The device could be connected with the PC using Wi-Fi or USB-cable for more detailed analyzing of all parameters of the research.
Several researches could be stored in the device with the information of time and date of the research. Time and date are able to be fixed by means of non-volatile clock of real time. Special place on the clock chip was designed for replaceable battery. It was made for stable work of the clock of real time if the battery of the device is low.
Before the research beginning, a disposable cartridge was connected with USB port with activated device.
For taking 20±5 μl of native capillary blood sample from distal phalange of fourth finger the skin was punctured with a standard scarifier. Analyte was placed into the measuring chamber of disposable cartridge. Within 5 – 6 minutes testing of early stages of fibrogenesis (adhesion/aggregation) was carried out; the result was seeing on device LCD-display and on PC for detailed interpretation of results obtained.
- А0 – the initial amplitude
- A1 – amplitude at moment in time t=0.3 minutes
- А2 – amplitude at moment in time t=2 minutes
- А4 – amplitude at moment in time t=4 minutes
- А5 – amplitude at moment in time t=5 minutes
Verification of indices obtained by using portable device were compared with results obtained by using patented and widespread method of low-frequency piezothromboelastography (LPTEG)  by piezothromboelastograph ARP-01M “Mednord” (2010/09767). In Fig.3. ARP-01M is shown.
The application of method of LPTEG allows in real-time mode to assess rapidly the functional state of hemostasis system and accepting identified hemostasiological disorders to prescribe the proper therapy followed by monitoring of its effectiveness .
For verification of test results were estimated parameters of healthy volunteers of the Siberian population obtained by using ARP-01M “Mednord”:
- t1 (contact coagulation phase time) = 0.8 – 1.6 min
- KTA (thrombin activity constant) = 28…38
- t2 (reaching of constant thrombin time) =3.5 – 4.8 min .
The first jump till 0.3 minutes requires further research, most probably, this value depends on the blood protein composition.
Thus, it was decided to accept the delta amplitudes at moments in time 2, 4 and 6 minutes from А1 (0.3 minutes) and the angle between the points on the curve at moments in time 0.3 and 2 minutes as data of portable device
Results obtained of testing of Patient 1 in state of “normal coagulation” are shown on Fig.4.
Data of LPTEG (А) indicate t1=1.4 minutes; t2=4.1 minutes; KTS=35.7. Data from portable device (В) indicate ΔА2=230 R.U.; ΔА3=360 R.U.; ΔА4=380 R.U.; ∟α=28.
Results obtained of testing of Patient 2 in state of “hypocoagulation” are shown on Fig.5.
Data of LPTEG (А) indicate t1=2.8 minutes; t2=5.2 minutes; КТА=40. Data from portable device (В) indicate ΔА2=140 R.U.; ΔА3=220 R.U.; ΔА4=220 R.U.; ∟α=19, what is significantly less than the corresponding results for Patient 1.
The presented data indicates the difference of parameters between Patient 1 and Patient 2 with normal and hypocoagulational states and has the ability for deviation identification.
The paper presents the portable device for express assessment of functional state of hemostasis system. The device consists of disposable cartridge and receiving unit for data processing.
The main stages of the disposable cartridge developing were the selection of optimized sensor material, the resonant frequency of the sensor and the size of the measuring chamber for tasting required amount of analyte – the whole capillary blood. For processing and interpretation of the test results with disposable cartridge obtained the reliable receiving device for “point-of-care” use was developed.
The vascular platelet hemostasis among healthy volunteers of the Siberian population was assessed in real-time mode. Research results from portable device were compared with the method of low-frequency piezothromboelastography (piezothromboelastograph ARP-01M “Mednord” 2010/09767).
Data received presented significant difference between test results of Patient 1 (normal coagulation) and Patient 2 (hypocoagulation) and results obtained showed a high correlation with method of low-frequency piezothromboelastography.
The presented research demonstrates the perspectives of application of the portable device for vascular platelet hemostasis assessment for point-of-care” use.
. I. Tyutrin, “Device for express assessment of functional state of hemostasis system”, RU Patent № 2693939, 2018.
. V. Udut, “Technology low-frequency piezoelectric thromboelastography in evaluation of haemostatic potential”. Journal of new medical technologies, vol. 4, pp. 104-113, 2016.
. O. Brazhnikova, “Typical errors in the preanalytical phase of laboratory”. Concilium Meducim, vol. 4, pp. 84-90, 2017.
. I. Tyutrin, “Assessment of functional state of hemostasis system method”, RU Patent № 2282855, 2014.
. I. Tyutrin, “Data base of hemostatic potential researches of healthy Siberian volunteers”, Certificate № 2019620555, 2019.
. I. Galastyan, “Introduction to hemostasis, blood products of today and their impact on coagulation”. Medical advice, vol. 5-6, pp. 11-16, 2013.
. E. Fanaskova, “Possibility of application of low-frequency piezothromboelastography method for the evaluation of haemostatic potential of blood in coronary bypass surgery on the background of long aspirinotherapy”. Bulletin of Siberian Medicine, vol. 3, pp. 145-155, 2017.
. O. Tarabrin and S. Scherbakov, “Features of diagnosis of hemostatic disorders and optimization of infusion therapy for severe destructive pancreatitis”. Emergency medicine, vol.2, pp. 40-44, 2017.
. T. Vavilova, “How to create a laboratory examination program for a patient with blood-clotting disorders”. Atherothrombosis, vol. 2, pp. 95-108, 2017.
. A. Magnette, “Pre-analytical issues in the haemostasis laboratory: Guidance for the clinical laboratories”. Thrombosis Journal, vol. 14(49), pp. 1-14, 2016.
. K Karkouti, “Pont-of-Care Hemostatic Testing in Cardiac Surgery: A Stepped-Wedge Clustered Randomized Controlled Trial”. Circulation, vol. 134. 2016.
. B. Akselrod (2019, october 19), «РОСТ method in anesthesiology practice».
. L. Li, “Evaluation of coagulability of blood plasma by the method of laser speckle correlation”. Biomedical Engineering, vol. 52(3), pp. 177-180, 2018.
. Website “Mednord-T” LLC. Available: http://mednord-t.ru/informaciya/
. Website Arduino Company. Available: https://www.arduino.cc/