Effect of prostate volume on the peripheral nerve block anesthesia in prostate biopsy

Objective To evaluate the anesthetic efficacy of periprostatic nerve block in transrectal ultrasound(TRUS) guided biopsy on different prostate volume. Methods A total of 568 patients received prostate biopsy in Department of Urology, Subei People's Hospital from May 2013 to September 2015 were retrospectively studied. All patients were divided into local anesthesia group and nerve block group according to different way of anesthesia. Then each group was divided into four subgroups(20-40 ml, >40-60 ml, >60-100 ml and >100 ml subgroups) according to different prostate volume range. After being anaesthetized successfully, patients in two groups underwent prostate biopsy, visual analogue scale(VAS) scores, visual numeric scale(VNS)scores and complications were recorded and analyzed. At inter-group and intra-group in local anesthesia group and nerve block group, Mann-Whitney U test of non-parametric analysis and single factor variance analysis were used to compare the VAS scores and the VNS scores respectively, and chi-square test was used to compare the rates of complication. Results The VAS scores of four subgroups: local anesthesia group: 1.9±0.9, 2.8±1.5, 3.8±2.3 and 5.3±2.5; nerve block group: 1.5±0.7, 2.0±0.8, 2.9±1.7 and 4.2±2.0. The VNS scores: local anesthesia group: 3.4±0.6, 2.9±0.6, 2.7±0.5 and 1.6±0.7; nerve block group: 3.7±0.5, 3.3±0.4, 3.0±0.8 and 2.0±0.7. The VAS scores and the VNS scores had significant differences (Z=-3.637-98.253, all P 0.05). Conclusion Compared with local anesthesia, ultrasound guided prostate peripheral nerve block anesthesia has great analgesic effect and high safety, but for patients with a large prostate volumethe analgesic effect is inefficiency. Key words: Prostatism; Biopsy; Peripheral nerve block anesthesia