The Effect of Local Anesthetic and Clonidine on the Cutaneous Silent Period During Spinal Anesthesia

The Effect of Local Anesthetic and Clonidine on the Cutaneous Silent Period During and After Spinal Anesthesia

The cutaneous silent period is a non-invasive technique that gives insight into the function of thin A delta fibers and as such can be a complement to conventional electrophysiological methods used to study the peripheral nerves. Clonidine is a selective partial agonist of the alpha-2 receptors which, added intrathecally to levobupivacaine, enhances the effect of a local anesthetic, prolongs sensory and motor block during local anesthesia and extends the length of post-operative analgesia. It is believed that clonidine achieves this effect by activating the postsynaptic alpha-2 receptors in the gelatine substance of the spinal cord and blocking the conduction of A-delta and C fibers. The aim of the study is to examine functional changes of Aδ - fibers during the application of spinal anesthesia by measuring the cutaneous slinet period and compare the effect of intrathecal administration of a combination of local anesthetic and clonidine in the quiet skin period in relation to the application of local anesthetic only.

Inclusion Criteria:

ASA one and two status BMI 18,5 to 24

Exclusion Criteria:

Coagulation disorders Polyneuropathy Diabetes mellitus Alcoholism Systemic inflammatory and malignant diseases Stroke