Mixture Nitrous Oxide - Oxygen 50-50% in Transrectal Prostate Biopsy Guided by Ultrasound

Introduction:

Transrectal ultrasound-guided prostate biopsy (TUGP) is currently the gold standard method used for early cancer diagnosis of this gland, when associated with PSA plasma measurement. Although well tolerated by many patients, about 65-90% of men undergoing BPTU complain of discomfort, associated or not to pain. For better tolerance, various methods of analgesia and / or sedation have been proposed, such as nerve block periprostatic ( or intraprostatic, topical anesthesia with lidocaine or EMLA at the puncture site , general anesthesia with propofol and remifentanil and other invasive techniques.

Inhalation of N2O-O2 50-50% by self-demand valve proposed in this study can be a good alternative to invasive methods to be a safe technique, cost-effective, which promotes analgesia on demand, in order to increase the tolerance painful procedures as TUGP, regardless of the presence of anesthesiologists.

Nitrous oxide (N2O) can be self administered for analgesia in various procedures such as drug joint intra injections, vascular access puncture, flexible sigmoidoscopy and colonoscopy, ophthalmic procedures and prostate biopsy. In Europe it is used in emergencies in the care and transport accidents in ambulances.

The objective is to evaluate the efficiency of inhalation of N2O-O2 50-50% by self-demand valve, comparing it to a placebo group. In addition, investigators evaluated side events such as the adverse effects of administration of nitrous oxide to discuss their security procedures without the presence of anesthesiologist.