Pharmacodynamic Effects Of Fentanyl With Different Concentrations On Inhibiting Body Movement By Propofol Inelderly Patients During Colonoscopy

【Objective】To evaluate the pharmacodynamic effects of fentanyl with different concentrations on inhibiting body movement by propofol in elderly patients during colonoscopy.【Methods】A retrospective review was conducted for90patients treated with colonoscopy, in which the ASA grade was II or III, the age span was from75to89, the body mass index span was from19to27kg/m2and the gender was unlimited, were randomly divided into three groups equally（n=30per group）: the control group, the F0.5group and the F1.0group injected with different concentration of fentanyl, respectively. All the patients were injected with propofol via plasma target controlled infusion(TCI). And the first initial target concentration of propofol in three groups was2.0μg/ml. After the plasma concentration and the effect-site concentration were maintained balance, the initial target concentration of propofol in different group were2.0,1.5and1.0μg/ml, respectively. The intended target concentration of propofol was sustained for3mins, and all patients were examed using the Observer’s Assessment of Alertness/Sedation Scale(OAAS), then the colonoscopy was performed. The TCI would be finished when the colonoscopy was stop. The concentration of propofol in the process was used with neighbouring unit according to the body dynamic response of the previous patient. And the ratio of propofol in each adjacent patients was1.2. The MAP, HR, SpO2, AAI, OAAS, and the body dynamic response in different times(including T0, T1, T2, T3, T4) were collected in the process. The average index-data before2mins of the body dynamic response were be as the data before the body dynamic response in patients with positive reaction. And the max index-data within2mins of the body dynamic response were be as the data after the body dynamic response. The time of the processing, waking, discharging, and the adverse reaction including circulating inhibition, respiraing inhibition and other reaction were collected. The EC50of propofol were examed using by Dixon-Broenlee model, and the AAI50were examed using by Probit analysis. The difference was statistically significant as P＜0.05.【Results】 The EC50and95%CI of the controlled group, F0.5group and F1.0group were 3.08(2.78～3.42)、2.75(2.50～3.02)、2.05(1.98～2.13) μg/ml, respectively; the EC50of propofol was reduced as the concentration of propofol(P<0.05). The AAI50were29,31,34, respectively; and the AAI50was increased as the concentration (P<0.05). Compared with that in patients with negative reaction, The AAI and the OAAS was higher(P<0.01) in patients with positive reaction. The MBP and HR were declined significantly in T1、T2、T3、T4compared with that in T0(P<0.01). The MBP and HR were declined significantly in F1.0group compared with that in controlled group, and so as that in the F1.0and F0.5group (P<0.05).The ratio of the adverse reaction including hypotension and bradycardia in F0.5and F1.0group were lower than that in controlled group(P<0.05). The cases of respitatory depression and intraoperative awake in controlled group, F0.5and F1.0group were8,6,7(4,6,9), respectively, but no significant adverse reaction in the process. The score of bloatin, bellyache in F1.0group were lower than that in controlled group and F0.5group(P<0.05); The time of waking, discharging in F1.0group were less than that in controlled group and F0.5group(P<0.05). There was no other adverse reaction in the process.【Conclusion】The EC50was reduced and the sedation depth was lessen in elderly patients with colonoscopy anesthetized by propofol mixed with fentanyl using TCI in the process. The hemodynamics were more stabilization and the adverse reactions was reduced in patients with fentanyl as the concentration of1μg/kg.