Cardiac safety of intraoperative fluid therapy regimens in patients with concomitant coronary heart disease during major abdominal surgery

Myocardial biomarkers such as brain natriuretic peptide (BNP) and brain natriuretic peptide amino-terminal prohormone (NT-proBNP), cardiac troponins (cTn), C-reactive protein (CRP) are considered as key in the strategy of treatment and prognosis for cardiovascular diseases. It is relevant for patients with high cardiological risk during major abdominal surgery and important in the context of preventing cardiac complications in the perioperative period. The aim. To assess the cardiac safety of intraoperative fluid therapy regimens in patients with high cardiac risk after major abdominal surgery by analyzing the dynamics of NTproBNP, Troponin I and CRP indicators. Materials and methods. The study included 89 patients who were divided into two groups depending on the tactics of the intraoperative fluid therapy: liberal and relatively restrictive. Continuous monitoring of macroindicators of cardiovascular system, quantitative assessment of myocardial damage biomarkers (TnI, NTproBNP) and CRP by enzyme-linked immunosorbent assay were performed at three stages - before surgery, immediately after and in the first 18–24 hours. Results. The rate of intraoperative fluid therapy was significantly different in two groups: in the restrictive 7.0 ± 0.2 ml/kg/h (n = 45), liberal 13.9 ± 0.6 ml/kg/h (n = 44). Evaluation of the dynamics of myocardial damage biomarkers revealed no differences in the levels of Troponin I and NP-proBNP at the first stage of the study. In the early postoperative period, the level of NP-proBNP in the second group was significantly higher than that in the first, 123.1 pg/ml and 68.0 pg/ml, respectively. An increase in Troponin I levels in the postoperative period was detected in 5 patients of the first group and in 6 – of the second, and it was diagnosed as myocardial injury after noncardiac surgery (MINS). Conclusions. The study has demonstrated the relative safety of fluid therapy regimens in patients with concomitant coronary heart disease without manifestations of congestive heart failure during major abdominal surgery. The regimen with relative fluid restriction has appeared to be preferable due to less response induction from compensatory mechanisms with normal NT-proBNP values. Adequate monitoring of cardiovascular system parameters and control of the dynamics of myocardial damage biomarkers can be the key in preventing such severe complications as postoperative myocardial infarction.