Effect of age factor on sedative efficacy of propofol given by closed-loop infusion in patients undergoing gynecological laparoscopic surgery

Objective To evaluate the effect of age factor on the sedative efficacy of propofol given by closed-loop infusion in patients undergoing gynecological laparoscopic surgery. Methods A total of 100 patients, weighing 55-75 kg, of American Society of Anesthesiologists physical statusⅠor Ⅱ, scheduled for elective gynecological laparoscopic surgery under general anesthesia, were divided into 2 groups (n=50 each) according to age: middle-aged group (45-64 yr) and elderly group (65-75 yr). Propofol was given by closed-loop infusion, and the target plasma concentration was automatically regulated to maintain bispectral index (BIS) value within the target range of 45-55.Remifentanil was given by target-controlled infusion at a target plasma concentration of 2-6 ng/ml to maintain anesthesia, and cisatracurium was injected intermittently to maintain muscle relaxation.The total consumption of propofol and remifentanil, regulating frequency of propofol, time ratio of BIS40-60, global score reflecting performance of closed-loop infusion system, emergence time and extubation time were recorded. Results Compared with middle-aged group, the time ratio of BIS40-60 was significantly increased, global score was decreased, the total consumption of propofol and remifentanil was significantly decreased, the regulating frequency of propofol was increased (P 0.05). Conclusion The sedative efficacy of propofol given by closed-loop infusion is influenced by age factors when used for gynecologic laparoscopic surgery, and the stability in elderly patients is superior to that in middle-aged patients. Key words: Propofol; Drug delivery systems; Age factors; Aged