Thromboelastometry for predicting hemostasis disorders after cardiopulmonary bypass during cardiac surgery

Abstract

   Introduction. Assessment of the state of the hemostasis system in cardioanesthesiology is carried out both clinically and using standard laboratory tests — thromboelastography (TEG), rotational thromboelastometry (ROTEM), or a combination of both. Both TEG and ROTEM are designed to detect disorders in the hemostasis system in real time.   Aim – to evaluate the informativeness of ROTEM performed at the stage of cardiopulmonary bypass (CPB) before neutralization of heparin with protamine and to study the prognostic value of this study in assessing the risk of postoperative bleeding during cardiac surgery with a high risk of bleeding.   Materials and methods. The assessment of the diagnostic significance of ROTEM studies at the CPB stage is based on the observation of 31 patients operated on from July to October 2018. The median age of these patients was 55 years (31–72 years). The criteria for inclusion of patients in the study were the performance of planned cardiac surgery with a high risk of bleeding: operations on the aorta, combined operations (coronary bypass surgery and/or surgery on the valve(s), multivalve correction), including repeated. Methods of descriptive statistics, correlation and comparative analyses, and ROC-analysis were used to assess the diagnostic and prognostic capabilities of ROTEM research during CPB against the back=-ground of high doses of heparin.   Results. A statistically significant linear correlation was noted between A5 and MCF indicators in EXTEM, FIBTEM and PLTEM tests performed both during and after CPB. The results obtained indicate that determining the cause of bleeding and deciding on the choice of therapy is possible significantly earlier than the MCF indicator is determined, namely 5 minutes after the start of blood clotting in the ROTEM study. The informative value of ROTEM studies performed during CPB is shown, however, when interpreting the results, it is necessary to focus not only on the reference intervals, but also on the obtained cut-off levels for ROTEM parameters during CPB for early detection of hypofibrinogenemia or thrombocytopenia after CPB.   Conclusion. ROTEM performed with the use of high doses of heparin during CPB is informative for the choice of pathogenetically justified therapy for possible bleeding.