A Meta-analysis of Local Anesthesia for Transrectal Ultrasound-guided Biopsy of the Prostate

This meta-analysis evaluated the efficacy and safety of periprostatic nerve block (PPNB) and intrarectal local anesthestic (IRLA) gel in alleviating pain during prostate biopsy. Electronic databases MEDLINE, Cochrane Central Register of Controlled Trials and EMBASE were searched to identify all randomized controlled trials comparing PPNB with periprostatic placebo injection, no injection or with IRLA. Studies for inclusion were identified and extracted by two authors independently. The main outcome measure was patients' assessment of mean pain scores on a 10-point scale at the end of the biopsy procedure. Secondary outcomes were complications and adverse events. Continuous data from the trials were combined by calculating the weighted mean difference (WMD) with its 95% confidence interval. In total, 25 studies met the inclusion criteria. Twenty studies involving 1685 patients compared PPNB with either no anesthesia or with placebo injection controls, showing a significant reduction in pain score in the anesthetic group (WMD -2.09, 95% CI -2.44 to -1.75, P<0.00001). Five studies with 466 patients compared IRLA and control. Although IRLA was associated with pain reduction, the effect size was not statistically significant (WMD -0.22, 95% CI -0.56 to 0.12). Six studies with 872 patients compared PPNB with IRLA, showing a significant pain reduction in the former group (WMD -1.53, 95% CI -2.67 to -0.39, P=0.008). No trials reported an increase in complications in the treatment arms. In conclusion, the evidence from randomized controlled trials shows that local anesthetic given as a PPNB, but not as an intrarectal instillation, is effective and safe in alleviating pain from transrectal ultrasound biopsy of the prostate.