Comparison of effects of etomidate versus midazolam on hemodynamics and protection of myocardium during tracheal intubation in patients undergoing off-pump coronary artery bypass grafting

Objective To investigate the effects of etomidate and midazolam on hemodynamics and protection of myocardium during tracheal intubation in patients undergoing off-pump coronary artery bypass grafting (OPCAB). Methods Seventy-eight patients with OPCAB hospitalized in Jiaozuo People’s Hospital from January 2017 to July 2019 were selected, and they were divided into etomidate group (group A, 39 cases) and midazolam group (group B, 39 cases) according to the random number table method. Group A and group B were intravenously injected with etomidate and midazolam respectively; and both groups were intravenously injected with fentanyl + pipecuronium bromide for anesthesia induction, and then were given propofol + piperacium bromide + fentanyl for anesthesia maintenance. The hemodynamics, such as heart rate (HR), mean arterial pressure (MAP), mean pulmonary artery pressure (MPAP), pulmonary artery wedge pressure (PAWP), vascular resistance, such as systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), and oxygen metabolism, such as mixed venous oxygen saturation (SvO2), oxygen supply index (DO2I), oxygen consumption index (VO2I), were monitored during anesthesia. The above indicators were recorded before tracheal intubation (T0), after intubation immediately (T1), at 1 min after intubation (T2), 5 min after intubation (T3) and 10 min after intubation (T4). Serum cardiac troponin I (cTnI) level was measured before anesthesia, at the end of surgery and at 6, 12 and 24 h after surgery. Results Compared with levels at T0, the HR and MAP were increased at T1 and T2 in both groups, and the HR in group A was lower than that in group B (P 0.05). Compared with levels before anesthesia, the serum cTnI levels in the two groups were increased at the end of surgery and at 6, 12 and 24 h after surgery (P 0.05). Conclusions Compared with midazolam, etomidate is more beneficial to sustaining hemodynamic stability during tracheal intubation in patients with OPCAB during anesthesia induction, and their roles in oxygen metabolism balance and myocardial protection are comparable. Key words: Etomidate; Midazolam; Off-pump coronary artery bypass grafting; Hemodynamics; Vascular resistance; Myocardial injury