Observer’s Assessment of Alertness/Sedation-based titration reduces propofol consumption and incidence of hypotension during general anesthesia induction: A randomized controlled trial

Abstract

Administration of a single propofol bolus dose for anesthesia induction causes hypotension. We included 160 patients (74 males and 86 females; mean age, 42.4 ± 10.7 [range: 18–60] years) with the American Society of Anesthesiologists status I–II undergoing elective surgery under general anesthesia. Using simple randomization, the patients were divided into a conventional group ( n = 80; received 2 mg/kg propofol at a rate of 250 mg/min) and titrated group ( n = 80; received propofol at a rate of 1 mg/kg/min until the Observer's Assessment of Alertness/Sedation scale score reached 1 point). Fentanyl (4 µg/kg) and cisatracurium (0.2 mg/kg) were administered, as appropriate. Systolic blood pressure, diastolic blood pressure, mean blood pressure, and heart rate were recorded at different time points. Propofol consumption, hypotension, and other adverse events were recorded. All the patients were intubated without awareness. Compared with the conventional group, the titrated group showed more stable blood pressure ( p < 0.05), as well as a lower decrease in systolic blood pressure, mean blood pressure at 1 and 3 min, and diastolic blood pressure at 1 min after propofol administration ( p < 0.01). Moreover, compared with the conventional group, the titrated group showed a lower post-intubation hypotension incidence (9 vs. 19 cases; p = 0.04), as well as lower total propofol dosage and propofol dose per kilogram of body weight (93.57 ± 14.40 mg vs. 116.80 ± 22.37 mg and 1.73 ± 0.27 mg/kg vs. 2.02 ± 0.08 mg/kg, respectively, p < 0.01). Compared with conventional propofol usage, titrated propofol administration can reduce the incidence of hypotension and propofol consumption during anesthesia induction.