Comparison of ultrasound guided interfascial obturator nerve block with and without peripheral nerve stimulation in transurethral resection of bladder tumors under spinal anesthesia

Transurethral resection of bladder tumor is a commonly done theraputic procedure for bladder tumors.Spinal anesthesia provide many advantages over general anesthesia such as reduced risk of bleeding,early recognisation of bladder perforation and avoiding complications assosiated with general anesthesia in geriatric popuation.The only short coming with spinal anesthesia is sparing of obturator nerve which can trigger inadverent adductor muscle spasm and thus may cause bladder laceration,perforation etc.Spinal anesthesia with a selective obturator nerve block is an alternative to general anesthesia for TURBT.Beacause obturator nerve is very thin and embedded in an  intermuscular septum,it is difficult to be electriclly stimulated.moreover it is difficult to be visualized even in ultrasound images,so interfascial plane block is administered.thus this study will evaluate whether simultaneous use of peripheral nerve stimulation along with ultrasound guidance can offer any advantage over sole use of ultrasound.