Reaction of the hemocoagulation system to tissue hypoxia in patients with chronic obstructive pulmonary disease

Background. Nowadays little data related to the hemostatic system and fibrinolysis in patients with chronic obstructive pulmonary disease (COPD) are available. This is due to the lack of standardized methods for studying the hemostasis system, as well as to the lack of a single functional test that allows the evaluation of the complete fibrinogenesis cycle in whole blood.Aim. The aim of our study was to develop a functional test capable of analyzing the blood gas composition in the “point-of-care test” method for the evaluation of the hemostatic potential in patients with COPD, based on a standardized test stimulus, which is tissue hypoxia. The current level of clinical and laboratory diagnostics requires personification and research of the hemo-coagulation system in real time (point-of-care test), which allows low-frequency piezotromboelastography(NVTEG) to be performed.Materials and methods. NVTEG was chosen to estimate the state of the hemocoagulation system. Ten patients with COPD and 10 healthy volunteers were examined. Hypoxia was selected as a standardized test stimulus. Hypoxia conditions were caused by smoking one standard cigarette (composition: resin 10 mg/cig., nicotine 0,7 mg/cig., CO 10 mg/cig.). The degree of tissue hypoxia was assessed with the GASTAT-navi blood gas analyzer.Results. The study has shown that in response to the standard test stimulus, which is the tissue hypoxia caused by smoking of a standardized cigarette, two types of haemostatic potential reaction were detected both in patients with COPD and healthy volunteers. The first type of reaction – “hypercoagulation” – is characterized by the formation of chronometric and structural hypercoagulation at all stages of fibrinogenesis and increased coagulation activity by 25–30% compared with the response in healthy individuals. The second type of reaction – “hypocoagulation” – is characterized by the formation of chronometric and structural hypocoagulation, a decrease in coagulation activity by 25–30% compared with the response in healthy individuals.Conclusion. Test stimulus, which acts as tissue hypoxia, causes a uniform spectrum of changes in the blood gas composition and hemocoagulation system in both healthy volunteers and patients with COPD. The possibility of online assessment of all stages of fibrinogenesis makes it possible to stratify patients with COPD by type of reaction, which is certain to have an important diagnostic and prognostic value and in the future will allow a more personified approach for choosing the treatment tactics

Possibility of application of low-frequency piezothromboelastografy method for the evaluation of haemostatic potential of blood in coronary bypass surgery on the background of long aspirinotherapy

Aim. To assess the hemostatic system on the aspirin therapy background using the VerifyNow Aspirin test, as well as examining platelet aggregation and low-frequency piezothromboelastography in patients with coronary artery disease during coronary artery bypass grafting.Materials and methods. 100 people with coronary artery disease who were taking aspirin (75–100 mg daily) for more than 1 year were examined. The study was performed in the perioperative period of coronary bypass surgery without aspirin withdrawal. Evaluation of hemostasis was performed by the VerifyNow Aspirin тest (USA), platelet aggregation (Нelena Laboratories AggRAMTM, Britain) and the low-frequency piezothromboelastography (ARP-01M “Mednord”, Russia).Results. Patients included in the study were sensitive to aspirin when under long-term administration of a drug: indicator test was VerifyNow ARU 496,9 ± 21,3)%, the platelet aggregation to ADP and adrenaline was reduced by 46% and 52%, respectively. In the early postoperative period platelet aggregation of ADP decreased by 73,2%, collagen – 75,9%, and adrenaline – 82,64% in comparison with the control group.Perioperative hemorrhagic complications in the study group were not observed. Reduction of platelet aggregation after aspirin therapy was accompanied by an increase in thrombin activity of the blood, which allows for evaluation of the method of low-frequency piezothromboelastography (LPTEG). In the early postoperative period, the results of LPTEG, thrombin potential, and anticoagulant and fibrinolytic activity of blood were partially normalized without reaching the level of the control group.Conclusion. For the evaluation of hemostasis under aspirin therapy it is advisable to apply the low-frequency piezothromboelastography, which in contrast to the VerifyNow test and traditional platelet aggregation, allows one to reveal a degree of impairment in thrombin blood activity and to conduct an integrative assessment on all aspects of hemostasis