TRANSIENT RADICULAR IRRITATION AFTER SPINAL-ANESTHESIA INDUCED WITH HYPERBARIC SOLUTIONS OF CEREBROSPINAL FLUID-DILUTED LIDOCAINE 50 MG ML OR MEPIVACAINE 40 MG/ML OR BUPIVACAINE 5 MG/ML/

Background: Transient radicular irritation (TRI) is common after spina l anesthesia induced with hyperbaric lidocaine 50 mg/ml. The purpose o f this study was to determine the incidence of TRI after spinal anesth esia with hyperbaric lidocaine 50 mg/mi diluted with cerebrospinal flu id (CSF) 1:1 and hyperbaric mepivacaine 40 mg/ml and hyperbaric bupiva caine 5 mg/ml. Methods: Ninety ASA class I-TV patients undergoing most ly brief urological procedures under spinal anesthesia were randomly a llocated to receive either hyperbaric lidocaine 50 mg/ mi diluted with CSF 1:1 (Group L), hyperbaric mepivacaine 40 mg/ml (Group M) or hyper baric bupivacaine 5 mg/ml (Group B). Characteristics of the patients a nd details of the surgical procedures and spinal anesthesias were simi lar in all groups except for the intensity of motor block. The patient s were evaluated on the first postoperative day by an anesthesiologist who did not know which spinal anesthetic agent had been used. Results : Six patients (20%) in Group L, 11 patients (37%) in Group M and none (0%) in Group B experienced pain in the legs and/or back (TRI) after spinal anesthesia. Conclusion: TRI is frequent after spinal anesthesia induced with hyperbaric lidocaine 50 mg/ml diluted with CSF 1:1. The incidence of TRI after hyperbaric mepivacaine 40 mg/ml is of the same magnitude. TRI could not be observed after bupivacaine spinal anesthes ia.