Abstract
OBJECTIVE: To investigate the effects of goal-directed fluid therapy (GDFT) on volume load and hemodynamics in patients undergoing coronary artery bypass grafting (CABG). METHODS: This retrospective study analyzed data from 131 patients with coronary heart disease who underwent CABG between April 2020 and April 2023. Seventy-five patients who received GDFT were categorized as the observation group, while 56 patients who received routine liquid therapy served as the control group. Fluid intake and outflow, volume load, regional cerebral oxygen saturation (rSO(2)), central venous blood oxygen saturation (ScvO(2)), hemodynamic parameters, and blood lactic acid levels were measured at several time points: 30 min preoperatively (T0), 15 min after anesthesia induction (T1), 1 h intraoperatively (T2), 2 h intraoperatively (T3), and at the end of the operation (T4). Postoperative recovery and complication rates were also compared between the two groups. RESULTS: There were no significant group differences in total fluid input, red blood cell infusion rate, autologous blood transfusion rate, and bleeding amount between the two groups (all P>0.05). However, the amount of Ringer's solution, and fluid intake/output were significantly lower compared to the control group (all P<0.05). Conversely, the observation group had higher hydroxyethyl starch input and greater urine output than the control group (P<0.05). The cardiac output (CO) in the observation group was remarkably higher than that in the control group at T2-T4 (P<0.05), while stroke volume variation (SVV) was lower in the observation group (P<0.05). The rSO(2) and ScvO(2) in the observation group were notably higher at T2 to T4 than those in the control group (P<0.05). There was no significant difference in mean arterial pressure (MAP) and heart rate (HR) between the two groups at each time point (P>0.05). The cardiac index (CI) was higher while the central venous pressure (CVP) was lower in the observation group at T2-T4 than those in the control group (both P<0.05). Blood lactate levels were significantly lower in the observation group at T2 to T4 (P<0.05). The duration of postoperative assisted ventilation, positive inotropic medication, ICU stay, and the overall hospital stay of the observation group were shorter than those in the control group (P<0.05), and the incidence of postoperative complications was significantly lower than that in the control group (P<0.05). CONCLUSION: GDFT improves cardiac function and reduces cardiac volume load in patients undergoing CABG. It helps stabilize intraoperative hemodynamics, reduces blood lactate levels, enhances oxygen supply to brain tissue (as reflected by improved rSO(2) and ScvO(2)), and accelerates postoperative recovery. Additionally, it significantly lowers the incidence of postoperative complications.