[Comparative study between analgesic efficacy and safety of meperidine compared with lidocaine periprostatic infiltration in transrectal ultrasound guided prostate biopsy].

OBJECTIVES To assess the efficacy of intravenous analgesia with meperidine compared to periprostatic plexus infiltration with lidocaine, and safety of periprostatic local anesthesia. MATERIALS AND METHODS A prospective randomized study with 100 patients undergoing first or second prostate biopsy. We distribute patients in two groups, group A (50 patients) which was administered 50 mg of intravenous meperidine and group B (50 patients) receiving 5 mL of lidocaine 2% in the angle between prostate and seminal vesicles. Pain was assessed by Visual Analog Scale (VAS) and a questionnaire about the emotional impact. Procedure safety was obtained by telephone questionnaire about prostate biopsy complications. The statistical analysis used was chi square test, Student's t test and Kruskal-Wallis no parametric test. RESULTS Median age was 66 years (47-80) and both groups were homogeneous with regard to: PSA, prostate volume, core's number and educational level without significant differences. 74 patients (74%) had their first biopsy and 26 (26%) had their second one. The average number of core biopsy was 10,9 +/- 2, and VAS mean score for group A was 3,6 +/- 1,8 versus 3,2 +/- 2 Group B without significant differences (p>0,05). We found significant differences (p<0,05) between transducer introduction (3,9 +/- 1,9 group A/B group 4,3 +/- 2,2) and core biopsy (3,6 +/- 1,8 group A/B group 3,2 +/- 2,2). There were no differences between the data obtained with emotional impact test, age and educational level comparing to pain caused by prostate biopsy. Regard to the number of cores obtained there were no differences (p>0,05). Complications appeared in 12 patients (12%), 5 in the group of meperidine compared with 7 in the lidocaine without differences between them. CONCLUSION Periprostatic plexus blocked with lidocaine does not offer advantages respect to meperidine, despite the fact that this is a safe method that does not increase the number of complications. Placing transrectal transducer causes more pain than biopsy cores.