TRANSIENT NEUROLOGIC SYMPTOMS AFTER SPINAL-ANESTHESIA - A LOWER INCIDENCE WITH PRILOCAINE AND BUPIVACAINE THAN WITH LIDOCAINE

Background: Recent evidence suggests that transient neurologic symptom s (TNSs) frequently follow Lidocaine spinal anesthesia but are infrequ ent with bupivacaine. However, identification of a short-acting local anesthetic to substitute for lidocaine for brief surgical procedures r emains an important goal. Prilocaine is an amide local anesthetic with a duration of action similar to that of lidocaine. Accordingly, the p resent, prospective double-blind study compares prilocaine with lidoca ine and bupivacaine with respect to duration of action and relative ri sk of TNSs. Methods: Ninety patients classified as American Society of Anesthesiologists physical status I or II who were scheduled for shor t gynecologic procedures under spinal anesthesia were randomly allocat ed to receive 2.5 ml 2% lidocaine in 7.5% glucose, 2% prilocaine in 7. 5% glucose, or 0.5% bupivacaine in 7.5% glucose. All solutions were pr ovided in blinded vials by the hospital pharmacy Details of spinal pun cture, extension and regression of spinal block, and the times to reac h discharge criteria were noted. In the evening of postoperative day 1 , patients were evaluated for TNSs by a physician unaware of the drug administered and the details of the anesthetic procedure. Results: Nin e of 30 patients receiving lidocaine experienced TNSs, 1 of 30 patient s receiving prilocaine (P = 0.03) had them, and none of 30 patients re ceiving bupivacaine had TNSs. Times to ambulate and to void were simil ar after lidocaine and prilocaine (150 vs. 165 min and 238 vs. 253 min , respectively) but prolonged after bupivacaine (200 and 299 min, resp ectively; P < 0.05). Conclusions: Prilocaine may be preferable to lido caine for short surgical procedures because it has a similar duration of action but a lower incidence of TNSs.