Effects of different doses of alfentanil on cardiovascular response to rapid sequential induction of tracheal intubation in elderly patients: A parallel-controlled randomized trial

Background Rapid sequential induction (RSI) and intubation have been shown to be effective in preventing reflux aspiration in patients with a full stomach during anaesthesia induction and endotracheal intubation. However, there is currently no standardized operation protocol or anaesthesia induction drug standard for RSI and intubation. Furthermore, there is a lack of evidence regarding the use of RSI and intubation in patients older than 65. In this study, we aimed to investigate the cardiovascular effects of different doses of alfentanil combined with propofol and etomidate during RSI for tracheal intubation in elderly patients aged 65–80 years. This study was designed to investigate the impact of varying doses of alfentanil in conjunction with propofol and etomidate on the rapid sequence induction (RSI) of tracheal intubation in elderly patients aged 65–80 years. Specifically, we sought to compare the effects of different doses of alfentanil on cardiovascular responses to RSI and intubation in this specific population. Methods A total of 96 patients aged 65–80 years who underwent general anaesthesia with tracheal intubation were selected for this study. The patients were randomly assigned to one of four groups using a random number table. Group A patients received an induction dose of 10 µg/kg alfentanil, group B patients received 15 µg/kg alfentanil, group C patients received 20 µg/kg alfentanil, and group D patients received 25 µg/kg alfentanil. Heart rate (HR), mean arterial pressure (MAP), cardiac index (CI), and ejection fraction (EF) were measured at three time points: 5 minutes before anaesthesia induction (T0), 1 minute after endotracheal intubation (T1), and 5 minutes after endotracheal intubation (T2). Concurrently, 4 ml of arterial blood was collected from patients at three time points, and the concentrations of norepinephrine (NE) and cortisol (Cor) in plasma were detected. Occurrences of hypertension, hypotension, bradycardia and tachycardia after the induction of anaesthesia and during endotracheal intubation were noted and incidence determined. Results Compared with T0, the HR, MAP, NE and Cor concentrations in group A and group B were increased at the T1 and T2 time points, and the CI and EF values from ultrasound measurements were decreased ( P < 0.05). HR and MAP in groups C and D were increased at the T1 time point, while HR, MAP, concentrations of NE and Cor, CI and EF in group D were decreased at the T2 time point ( P < 0.05). The changes in HR, MAP, NE and Cor concentrations and CI and EF values in group C were more stable. The incidence of hypertension and tachycardia in group A was significantly higher than that in group C and group D, and the incidence of hypotension and bradycardia in group D was significantly higher than that in group A and group B ( P < 0.05). Conclusion Alfentanil 20 µg/kg for RSI in elderly patients receiving intubation can effectively inhibit the stress response, resulting in more stable haemodynamics. Trial registration ChiCTR2200062034 (www.chictr.org.cn)