Combining Use Of Oxycodone And Dexmedetomidine For PCIA In Old Patients After Open Gastrointestinal Tumor Resection Surgery

Objective : to investigate the effect of different concentration of oxycodone and dexmedetomidine on postoperative patient controlled intravenous analgesia in old patients after open gastrointestinal tumor resection surgery.Methods: Patients who underwent selective open gastrointestinal tumor surgery were enrolled. All patients received general anesthesia for surgery and the same set of patient controlled intravenous analgesia( reservoir bag volume 100 ml,background rate 2ml/h,additional dose 0.5ml and block time 15 minutes). Patients were randomly divided into three different analgesia regimen groups: O1 group(oxycodone 0.3mg/kg+dexmedetomidine 2.0ug/kg), O2 group(oxycodone 0.5mg/kg+dexmedetomidine 2.0ug/kg) and O3 group(oxycodone 0.7mg/kg+dexmedetomidine 2.0ug/kg). Record the pain score at postoperative 1, 2, 6, 12, 24, 36, 48 and 72 hours, include motion and resting pain score(VRS). Record the sedation(Ramsay) score; 48 hours after the operation, recorded the effective pressing PCIA in number; the occurrence of fever, nausea and vomiting, drowsiness, dizziness, skin itching and other adverse reactions of the situation; record the incidence of sinus tachycardia, sinus, hypertension, hypotension, low blood pressure, respiratory depression, and deep sedation were recorded in each group of patients after 72 h. record the first exhaust time, first defecation time and postoperative hospital stay in each group. Application of MMSE in the day before surgery on the cognitive impairment of the elderly have been exclude, cognitive function scores were performed on the fifth day after surgery. We also evaluated the satisfaction of patients at postoperative 72 hours;to evaluation of patients with analgesia satisfaction survey.Results: 1 general conditions: The age, height, body mass index(BMI), operation time, total amount of propofol and remifentanil in the three groups were not significantly different between each two groups.2 There were no significant differences in MAP, HR between the each two groups at T1, T2, T3, T4 T5, T6, T7, T8.3 There was no statistical significance in Ramsay score at each time-point among three group(P>0.05).4 There was no significant difference in the Ramsay scores of the three groups at each time point after operation(P>0.05).5 Postoperative analgesia was performed in five patients in group O1, one patient in O2 and one patient in O3. Comparison of the patients of additional analgesics in three groups, compared with the O1 group, O2 group and O3 group was significantly reduced, compared with O3 group, the difference was no statistically significant. Compared to the number of effective pressing O1, PCIA group was significantly increased, compared with the O2 group, O3 group had statistical significance(P<0.05), compared with O3 group, the difference was no statistically significant(P>0.05).6 Compared the detail of postoperative incidence of side effects between each group: the incidence of nausea and dizziness in group O3 was higher than that in group O2, the difference was statistically significant(P<0.05).there was no significant difference in the incidence of headache, fever and skin itching between the three groups(P>0.05).7 Mean arterial pressure in O1 group was higher than O2 group and O3 group at postoperative 1h, 2h, 6h(P<0.05). Heart rate in O2 group and O3 group was lower than O1 group at postoperative 1h, 2h, 6h(P<0.05). In three groups of patients, O1 group of two patients with postoperative hypertension.8 Three groups of patients in the first exhaust time after surgery, the first defecation time comparison: O1 group for the first exhaust time, the first defecation time was significantly shorter than the O2 group and O3 group, the difference was statistically significant(P<0.05). Three groups of patients with postoperative hospital days, the difference was not statistically significant(P>0.05).9 There was no significant difference in MMSE score between the three groups(P>0.05).10 Postoperative satisfaction survey of three groups of patients: patients in O2 group had best satisfaction of analgesia(P<0.05).Conclusion: Combing use of oxycodone and dexmedetomidine can improve the effect of postoperative patient controlled intravenous analgesia in old patients after open gastrointestinal tumor resection surgery. Oxycodone 0.5mg/kg+dexmedetomidine 2.0ug/kg provided sufficient analgesia and proper sedation, with lowest incidence of complications and best rate of satisfaction.