[Pharmacokinetics of lidocaine used for total spinal anesthesia--a comparison between cervical and lumbar injection].

We studied the effects of site of injection on the serum concentration of lidocaine following total spinal block. Six mg.kg-1 of lidocaine was given into the cervical (n = 11) or lumbar (n = 7) subarachnoid space in 10 patients. The mean maximum serum concentration of lidocaine in the cervical group was found to be significantly greater than that in the lumbar group. Lidocaine given into the cervical subarachnoid space seems to be infiltrated easily into the intracranial space and consequently into the systemic circulation.