Ketamine for postoperative analgesia in radical prostatectomy in combination with morphine, tramadol plus electroacupuncture technique or nalbuphine. 
Ntritsou V., Papagiannopoulou P., Vrigga M., Stefanović D., Kostoglou C., Zachariadou C. 
Anesthesia Department, «G. Gennimatas» General Hospital, Thessaloniki, Greece

Background and Goal of Study: The aim of this study was to compare the efficacy of postoperative analgesia and the incidence of adverse effects with intravenous (iv) administration of tramadol plus ketamine in combination with electroacupuncture (EA) technique versus the iv administration of opioids (nalbuphine or morphine) plus ketamine in patients undergoing radical prostatectomy (RP).
Materials and Methods: 105 patients scheduled for RP were randomly assigned in 3 groups. In Group 1 (n=35) morphine was administered [bolus dose (BD) 0.05mg/Kg and continuous infusion (CI) mg/24h=18-(agex0.15)], in Group 2 (n=35) tramadol (BD 1.5mg/Kg and CI 0.15mg/Kg/h) with EA technique and in Group 3 (n=35) nalbuphine (BD 0.5mg/kg and CI 0.15mg/kg/h). In all groups ketamine was also administered (BD 10mg and CI 0.15mg/Kg/h). Infusion pumps were designed to provide 24h postoperative pain relief. In Group 2 a certified acupuncturist placed needles into the LI4 point at a 2cm depth in both hands when the closure of the abdominal walls was initiated. EA was applied for 30min using an EA stimulator at a 100Hz frequency and a constant pulse program. EA was administered again at ST36 and LI4 points for 30min at a 4Hz frequency just after patient extubation. Pain intensity was evaluated at 6h and 24h postoperatively with Numerical Rating Scale at rest and movement. Rescue analgesia and adverse effects were also assessed at 6h and 24h postoperatively.
Results and Discussion: Demographic data were similar among groups. Patients in group 2 presented statistical significant lower pain scores at rest at 6h and 24h postoperatively compared to group 1 and 3 (p<0.05). At movement at 6h and 24h postoperatively group 1 showed statistical significant higher pain scores compared to group 2 (p<0.05), while there was no significant difference between other groups assessments. Analgesic consumption was significantly higher, at 24h in group 3 compared to groups 1 and 2 (p<0.05).  No statistical difference between groups was noted concerning adverse effects except for bowel movement where Group 2 showed significant faster bowel movement, at all time intervals, compared to group 1 and 3 (p<0.001).
Conclusion: In patients undergoing RP, the use of EA technique with the combination of iv administration of tramadol plus ketamine was more effective concerning postoperative pain relief and analgesic consumption compared to iv administration of nalbuphine or morphine in combination with ketamine.