Effect Of Ketamine, Dexmedetomidine As A Preventive Analgesic On The Analgesic Efficacy And Gastrointestinal Recovery After The Surgery

Objective:To evaluate the effect of Ketamine, Dexmedetomidine as a preventive analgesic on the analgesic efficacy of patient-controlled intravenous analgesia (PCIA) with morphine and on the gastrointestinal recovery after the surgery.Methods:Thirty patients with ASA physical status I or II, both gender, BMI index ranged from 18-23kg/m2, aged 25-60 years old, undergoing selective operation of gastrogastrostomy were randomized into 3 groups:group C (0.9%NaCl,4ml into epidural and 4ml iv.); group K(0.5mg/kg Ketamine into epidural and 4ml 0.9%NaCl iv.); group K+D (0.5mg/kg Ketamine into epidural and 0.5ug/kg Dexmedetomidine iv.). The preventive analgesics should be given before the operation started. Exclusion criteria included allergic to opioid, history of opioid abuse, spine malformation, abnormal hepatic function or renal function, unable to score senses, and blood loose greater than 500ml. Anesthesia was induced with Propofol 1.5-2mg/kg, Fentanyl 3ug/kg and Rocur 0.6mg/kg, maintained by Sevoflurane 0.7-0.9MAC and 1% Lidocaine+0.2% Decaine via epidural. After the operation and palinesthesia in the PACU, the PCIA with morphine was started and recorded. The analgesic efficacy and gastrointestinal recovery was observed, including VAS, morphine consumption, the adverse reaction of morphine (nausea, vomiting, itching) at the time point of lhr,4hr, 8hr,12hr,24hr.Results:Compared with group C, the VAS scores were significantly lower in group K at lhr,4hr and 8hr, while the VAS score significantly went up at 12hr. These two groups had no difference in morphine consumption and gastrointestinal recovery. The VAS scores in group K+D were significantly lower than group C and group K all the time. Its morphine consumption was significantly lower than other two groups and group K+D had an earlier gastrointestinal recovery.Conclusion:Ketamine as a preventive analgesic via epidural can enhance the analgesia efficacy of morphine at the early stage. Ketamine with Dexmedetomidine can decrease the comsuption of morphine, enhance the analgesic efficacy, reduce the adverse effect of morphine and improve the gastrointestinal function.