The aim of this study was a comparison between intrathecal meperidine
   and lidocaine 5% for onset of sensory blockade, level of sensory block,
   degree of motor blockade , duration of postoperative analgesia,
   hemodynamic changes, degree of nausea and Vomiting, pruritus and
   shivering for T.U.R Operation.

         60 patients with ASA I-III were divided randomly into intrathecal
   meperidine goup (n=30) and 5% lidocaine group (n=30). The first group
   received 1 mg/kg (2ml) meperidine and the second group received 
   100 mg of 5% lidocaine (2ml).  Thirty minutes before subarachnoid puncture
   all of the patients received 500ml ringer solution. Subarachnoid puncture
   was performed with the patient in the sitting position using a 23 gauge
   spinal needle at the lumbar level of L3-L4 and the patient immediately in the
   supine position.

          The onset time for sensory blockade was 3.99 minutes in the lidocaine
   group and 5 minutes in the meperidine group. The segmental level of
   analgesia was present in 28 patients in the lidicaine group .Duration of
   post operative analgesia was 354 minutes in the lidicanie group and 662
   minute in the meperidine group. Systolic arterial blood pressure and heart
   rate did not change significantly , and there was no difference between
   meperidine and lidocaine groups. Complication such as nausea and
   vomiting were similar in the two groups, but pruritus was seen only in patients
   receiving meperidine , and intraoperative sedation occurred in patients
   receiving meperidine more than the other group. No patients who
   received meperidine had postoperative shivering.

          So according to this study, Intrathecal meperidine used alone has
   advantages over lidocaine 5% for T.U.R. operation.