RETRACTED: Detection of large perforating artery by ultrasound prescan before obturator nerve block

Abstract

An obturator nerve block improves the quality of postoperative analgesia after lower extremity surgery [1]. An ultrasound-guided obturator nerve block is simpler to perform and more reliable than other landmark techniques [2]. We report a case where a large perforating artery was detected by ultrasound prescan before applying the obturator nerve block. A 75-year-old man with bladder cancer was scheduled to undergo transurethral resection of the bladder tumor. After induction of the spinal anesthesia, bilateral obturator nerve blocks were attempted by performing the interfascial approach at the level of the femoral crease. An ultrasound prescan indicated the presence of a large artery near the anterior branch of the right obturator nerve between the adductor longus and the adductor brevis (Figure). By using the ultrasound probe, we detected that it branched out from the right deep artery of the thigh. Therefore, the artery was considered a large perforating artery from the right deep artery of thigh. We could not detect a similar abnormal large performing artery from the left deep artery. We performed bilateral obturator nerve block to avoid the large performing artery from the right deep artery. An unintentional pucture of a large perforating artery puncture during obturator nerve block can cause some complications such as hematoma and local anesthetic intoxication. We recommend that the vasculature be confirmed by an ultrasound prescan prior to performing an obturator nerve block.