Effect Of The Application Of High Or Low Dose Remifentanil Combined With Propofol On The POCD Of The Gerontal Patients At Early Stage After The Abdominal Operation With The Guidance Of BIS

Objective: To investigate the effect of the application of high or low dose remifentanil combined with propofol on the POCD of the gerontal patients at early stage after the abdominal operation.Methods: 90 gerontal patients hospitalized in general surgery department and having abdominal operations from October, 2014 to August, 2015, aged from 65 to 80 with ASA I-II and operative duration of 2 to 6 hours were selected as participants and divided randomly into two groups: high dose group(H group) and low dose group(L group) with 45 patients each. Anesthesia was maintained by high dose remifentanil(0.3?g/kg/min) combined with propofol in H group and low dose remifentanil(0.2?g/kg/min) combined with propofol in L group, and during operation, the effect compartment concentration was regulated to ensure BIS was around 50±5. Cognitive function of all the patients was evaluated by Mini Mental State Examination(MMSE) 1day before operation and 2h, 6h, 24 h postoperatively, while MAP, HR, BIS were recorded as well as postoperative duration of opening eyes, extubation time, PACU care duration and Steward Awakening Score at the same time.Results:(1) Ratio of the duration on controlling the depth of anesthesia of the patients from both groups to target level, lighter than target level and deeper than target level to the duration of operation showed no statistical difference(P>0.05).(2) H group showed significant reduction on the intraoperative consumption of propofol compared with L group(P<0.05) while no significant difference was seen on the intraoperative consumption of atropine, ephedrine and Urapidil between the two groups(P>0.05).(3) The incidence rate of POCD of H group 6h after operation was significantly lower than that of L group(P<0.05) while no significant difference was seen 2h and 24 h after operation(P>0.05). Both groups showed lower MMSE scores of postoperative 2h,6h and 24 h than that of preoperation(P<0.05). H group showed significant higher MMSE scores than L group 6h after operation(P<0.05).(4) No significant difference could be seen between two groups on postoperative duration of opening eyes, extubation time, PACU care duration and Steward Awakening Score.(5) MAP of L group was significantly higher 1min after(T4) than before(T3) skin incision(P<0.05) while MAP of H group showed no significant difference. Further more, intraoperative MAP, heart rate and BIS were steadier in H group than L group especially during intubation and skin incision.Conclusion:(1) The results of this study indicate that total intravenous anesthesia of high or low dose remifentanil combined with propofol could both lead to transient reduction of cognitive function of gerontal patients after the abdominal operation and most patients could recover to preoperative level in the short term.(2) The application of high dose remifentanil wouldn't increase the risk of POCD at early stage after the abdominal operation and the incidence of delayed emergence from anesthesia, and is ideal for the recovery of the cognitive function of the gerontal patients at early stage.(3) Maintaining anesthesia with the guidance of BIS and hemodynamic indexes combined with operation process, high dose remifentanil could increase the target effect compartment concentration so as to reduce the consumption of propofol, which is conducive to lowering the incidence of POCD of gerontal patients at early stage.(4) The application of high dose remifentanil combined with propofol shows steadier hemodynamics and could optimize the controllability of the depth of anesthesia during perioperative period.