A Study of a New Local Anesthesia Method for Transperineal Prostate Biopsy

A Novel, Repeatable, and Effective Local Anesthesia Method for Transperineal Prostate biopsy-a Single Center Randomized Controlled Trial

In comparison with transrectal prostate biopsy, transperineal prostate biopsy has the advantage of better sampling from the anterior area, low risk of infection, and no rectal bleeding. The main problems associated with the transperineal method are pain control and additional general or spinal anesthesia. Three types of anesthesia have been reported for transperineal prostate biopsy: (1) spinal anesthesia; (2) general anesthesia; and (3) local anesthesia. From the viewpoint of patient selection (general anesthesia is contraindicated in some patients) and medical cost, local anesthesia is the most suitable choice for prostate biopsy. Periprostatic block is the standard method of local anesthesia for this procedure. However, periprostatic block is insufficient for transperineal prostate biopsy due to high pain sensitivity in this region. A number of new methods to eliminate pain have been reported, including (1) periapical triangle (PAT) block, (2) paraprostatic plus sexual nerve block, and (3) periprostatic block plus pudendal block.However, there is no anatomical basis for some of these methods, and there have been no randomized controlled trials to evaluate their effectiveness, and some methods are technically difficult to learn. In the previous perineal nerve autopsy, we found that there are two branches leading into the prostate and anterior lateral prostatic tissue, which is the main site of puncture pain. There is a fixed position where the two branches appear. Therefore, this anatomical position block may be a useful site for local anesthesia. We named this location the 'transperineal prostate biopsy local anesthesia switch' (abbreviated as TPA switch). In order to validate its effect, we organized this clinical trail.

Ninety patients scheduled for prostate biopsy will include in this study. The clinical trial validation process will be as follows: (1) all patients are randomly divided into three groups (Figure 1): group 1, subcutaneous local anesthesia+periprostatic block; group 2, subcutaneous local anesthesia+periapical triangle (PAT) block; group 3, subcutaneous local anesthesia+TPA switch (transperineal prostate biopsy local anesthesia switch) block; VAS scores for each puncture and complications will be recorded.

Inclusion Criteria:

• 1. ready to be performed transperineal prostate biopsy; 2. fully understand the protocol and aggree to undergo prostate biopsy with local anesthesia which might be elder methods or new experimental method.

Exclusion Criteria:

• 1.do not have the history of anaphylaxis or local anesthetic intoxation； 2. cardiac dysfunction or coagulation dysfunction; 3. Rectal disease which can not allowed to plug the ultrasound probe in; 4.do not fully understand our protocol; 5. do not aggree our protocol.