Objective To investigate the effects of esketamine used for coronary artery bypass grafting under extracorporeal circulation on patients' hemodynamics during the induction period of anesthesia and postoperative recovery.

Methods Sixty patients who underwent elective coronary artery bypass grafting (CABG) were selected. The patients were divided into esketamine group (ES group) and conventional general anesthesia group (G group) according to the randomized numerical table method, with 30 cases in each group. After entering the operating room, G group underwent conventional general anesthesia induction and anesthesia maintenance, while ES group slowly injected esketamine 0.3 mg/kg during the anesthesia induction period on the basis of G group. Esketamine 0.15 mg/kg/h was continuously injected during the anesthesia maintenance period until the end of the operation. Mean arterial pressure (MAP) and heart rate (HR) at the time points of immediate admission (T₀), preintubation (T₁), immediate intubation (T₂), 1 min after intubation (T₃) and 5 min after intubation (T₄), the total intraoperative sufentanil dosage, the number of cases of sustained arrhythmias (ventricular pre-systole, atrial fibrillation, ventricular fibrillation), electrical defibrillation after cardiopulmonary bypass, postoperative mechanical ventilation time, visual analog score (VAS) after extubation and at 12h, 24h, and 48h postoperatively, the number of patients with remedial analgesia in the postoperative period of 48h, the duration of stay in cardiac surgical intensive care unit (CSICU), and the incidence of other adverse reactions (choking, nausea and vomiting, pulmonary infection, and postoperative delirium) in the postoperative period of 48h were recorded in the two groups.

Results The MAP values at T₁, T₂ and T₄ in the ES group were higher than those in the G group (P ＜ 0.05). The HR values at T₁, T₂ and T₄ in the ES group were higher than those in the G group (P ＜ 0.05). The fluctuation of MAP and HR values between observation points in the ES group was smaller than those in the G group. The difference in the number of cases of arrhythmia and electrical defibrillation after aortic opening between the two group was not statistically significant (P ＞ 0.05). The intraoperative sufentanil dosage, postoperative mechanical ventilation time, and postoperative CSICU retention time were all lower in the ES group than those in the G group (P ＜ 0.05 to P ＜ 0.01). The incidence of choking during awakening was lower in the ES group than that in the G group (P ＜ 0.01). The VAS scores were lower in the ES group than that in the G group after extubation, and at 12 h, 24 h, and 48 h postoperatively (P ＜ 0.05 to P ＜ 0.01). The number of cases of remedial analgesia in the ES group was lower than that of the G group in the postoperative period of 48 h (P ＜ 0.05). The difference in the number of cases of adverse reactions such as nausea and vomiting, pulmonary infection, and postoperative delirium in the 48 h postoperative period was not statistically significant (P ＞ 0.05).

Conclusion The application of esketamine in patients under extracorporeal circulation for coronary artery bypass grafting surgery can maintain hemodynamic stability during the induction period and has the effect of reducing the intraoperative sufentanil dosage, alleviating postoperative pain, shortening the time of mechanical ventilation, reducing the incidence of choking and coughing during the awakening period of the patients and the time of staying in the cardiac surgery intensive care unit, which is beneficial to accelerating the recovery of the patients in the postoperative period.