Subcutaneous Tramadol Infiltration at the Wound Site Versus Intravenous Administration after Pyelolithotomy
BACKGROUND: Recently, the peripheral anesthetic effect of tramadol has been the theme of many studies. The postoperative analgesic effects of subcutaneous wound infiltration with tramadol have not been extensively studied and compared with those of intravenous administration. OBJECTIVE: To compare the therapeutic effects and complications of intravenous versus local wound infiltration of using tramadol following pyelolithotomy. METHODS: This double-blind study was carried out on 60 patients (age 18-60 y) of American Society of Anesthesiologists physical status I-II who were awaiting pyelolithotomy in Sina Hospital, Tehran, Iran, during 2006 and 2007. They were randomly assigned to receive intravenous or subcutaneous wound infiltration with tramadol. Vital signs, the intensity of pain (visual analog scale), and the level of consciousness (Ramsey Sedation Scale [RSS]), as well as the frequency of nausea and vomiting were recorded during 30 minutes to 1 hour after the patent entered the recovery room. Vital signs were also recorded every hour until 6 hours postoperatively and then on the day after the patient was transferred to the ward. RESULTS: The RSS was lower in patients who had received subcutaneous infiltration of tramadol (p < 0.001). A significant difference was noted in the severity of pain between the groups; it was higher in the group that received intravenous tramadol. The average time for the first meperidine requirement was 45.2 +/- 8.4 min (mean +/- SD) in the subcutaneous group and 21.6 +/- 12.4 min in the intravenous group. Total meperidine consumption was lower in patients who had received subcutaneous wound infiltration with tramadol compared with those who had received intravenous tramadol (p < 0.001). Nausea and vomiting were more frequent during the first hour of recovery; the complication, however, was less frequent in the subcutaneous group. CONCLUSIONS: Subcutaneous wound infiltration with tramadol reduces postoperative opioid consumption and produces less nausea and vomiting than does intravenous administration.