Risk assessment of cardial complications in patients with concomitant ischemic heart disease using different regimens of intraoperative fluid therapy
Authors: Morozova Ya.V. 
Published: October 2020

Objective. To investigate the incidence of postoperative cardiac complications when performing advanced surgical interventions for cancer in patients with concomitant coronary heart disease (CHD) using two different regimens of intraoperative fluid therapy.
Materials and methods. The study included 89 patients who underwent advanced surgery under general anesthesia. The division of patients into two groups was performed depending on the chosen way of intraoperative fluid therapy: the first (n=45) with a restrictive regimen (7.0±0.2 ml/kg/h), the second (n=44) – with a liberal (13.9±0,6 ml/kg/h). Groups of patients had no differences in anthropometric data, the volume of surgery, anesthesia. Intraoperatively, continuous monitoring of routine hemodynamic parameters (blood pressure, heart rate) and electrocardiography (ECG), quantitative assessment of biomarkers of myocardial damage (TnI, NTproBNP) by enzyme-linked immunosorbent assay in three stages (before surgery, immediately after and in the early postoperative period 18-24 h) of operation.
Results and discussion. None of the patients had critical incidents during anesthesia, some of them had postoperative complications that did not require significant correction, but only more careful monitoring. In all patients of both groups, stable hemodynamic parameters were observed in the perioperative period, which was ensured by the adequacy of anesthesia, fluid therapy and the use of maintenance doses of sympathomimetics (phenylephrine) if necessary. In the 1st group 8 patients (17.8 %) needed support with sympathomimetics, in the 2nd – 3 patients (6.8 %). The study of the dynamics of cardiac biomarkers revealed a slight increase in cardiac troponin I in both groups, which was within the upper limit of normal. A more significant increase in troponin levels (so-called myocardial injury) was found in 5 patients (11.1 %) of the 1st group and in 6 patients (13.6 %) of the 2nd group in the postoperative stage. In the study of the concentration of natriuretic peptide found a more significant increase in patients of group 2 in the postoperative period, but these values were within normal limits. Manifestations of heart failure decompensation were not found in either patient in either group. According to ECG monitoring, no ischemic changes were found in any of the patients, benign arrhythmias were detected in 5 patients (11.1 %) of the 1st group and in 7 patients (15.9 %) of the 2nd group. Signs of acute renal injury were not found in either patient of either group, all had sufficient diuresis and blood creatinine levels within normal limits in the perioperative period. According to the statistical indicators of stay in the intensive care unit and in the hospital, the patients of both groups did not differ from each other.
Thus, the study found no significant differences in the frequency of postoperative complications in patients with concomitant CHD when using relatively restrictive and liberal regimens of perioperative infusion therapy. The key point in the management of these patients is, in our opinion, the desire for “zero” balance by the end of the 1st day of the postoperative period and beyond. The main tools of the anesthesiologist are careful accounting of the injected fluid and its losses. This tactic may allow the use of a more liberal infusion regimen if necessary in patients without signs of heart failure.
Conclusions. Relatively restrictive and liberal regimens of perioperative fluid therapy can be safely used in patients with concomitant CHD without signs of heart failure, provided adequate monitoring and management within the “zero” fluid balance.