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

Summary

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.

Timeline

Start

2017-05-01

Primary completion

2027-09

Completion

2028-10

Publications

• Background Inghilleri M, Cruccu G, Argenta M, Polidori L, Manfredi M. Silent period in upper limb muscles after noxious cutaneous stimulation in man. Electroencephalogr Clin Neurophysiol. 1997 Apr;105(2):109-15. doi: 10.1016/s0924-980x(97)96579-6.
• Background Mota IA, Fernandes JB, Cardoso MN, Sala-Blanch X, Kofler M, Valls-Sole J. Temporal profile of the effects of regional anesthesia on the cutaneous reflexes of foot muscles. Exp Brain Res. 2015 Sep;233(9):2587-96. doi: 10.1007/s00221-015-4329-2. Epub 2015 May 30.
• Results Uncini A, Kujirai T, Gluck B, Pullman S. Silent period induced by cutaneous stimulation. Electroencephalogr Clin Neurophysiol. 1991 Oct;81(5):344-52. doi: 10.1016/0168-5597(91)90023-q.

Drugs

Indications

No indication recorded.