“PPB may provide better anesthesia because its action is proximal to the prostate with a block of more nerve fibers,” the authors comment.
Dr. Francesco Cantiello, at the Magna Graecia University of Catanzaro, and colleagues note that about a fourth of patients undergoing transrectal ultrasound-guided (TRUS) prostate biopsy experience significant pain. While periprostatic nerve block (PNB) is simple to perform and effective for pain control, encouraging results have been reported with pelvic plexus block.
The team compared the two analgesia techniques in 180 men undergoing TRUS biopsy. All received an intrarectal application of a topical anesthetic cream 10 minutes before the anesthetic injection.
Then, in 90 of the subjects, a periprostatic pelvic block was accomplished by injection of 2.5 mL of lidocaine/naropine “on each side into the pelvic neurovascular plexus lateral to the tip of the seminal vesicles under echo color Doppler guidance”. The other 90 men received a periprostatic nerve block by injections of the same agent “on each side into the neurovascular bundles at the prostate-bladder-seminal vesicle angle.”
After the procedure, the patients rated their level of pain at specific time points on a 0-10 visual analog scale. During the prostate biopsy per se, the pain score was 2.28 in the PPB group compared to 3.37 in the PNB group (p<0.001), the investigators report.
There was also a significant difference between groups in pain scores 30 minutes after the biopsy (2.02 vs 2.41; p=0.001).
The authors note, however, that the pain scores were higher than cited in the current literature. They think this may have been due to the relatively small amount of local anesthetic injected, and its placement several centimeters away from the target area “to avoid spreading anesthesia along the nerve fibers.”
Dr. Cantiello and colleagues also point out that dual anesthesia plus the use of Doppler ultrasound raises procedural costs. “Cost-effectiveness analysis is strongly advocated to specifically address this issue,” they suggest.
Pelvic Plexus Block is More Effective than Periprostatic Nerve Block for Pain Control During Office Transrectal Ultrasound Guided Prostate Biopsy: A Single Center, Prospective, Randomized, Double Arm Study