[Changes in human evoked spinal potentials (ESP) by epidural lidocaine].
Controversies exist on the sites of action of epidural anesthesia. Leading opinion says that it works on spinal nerve root. We examined ESP and tactile sensations in 4 patients during epidural anesthesia with lidocaine to determine the effects of the anesthesia on spinal cord. Prolongation of latency and decrease in amplitude of ESP appeared 10 min after injection of 1.5% lidocaine 4 ml, each parameter reaching maximum value of 115% and 60% of the control value 30 min afterwards, respectively. Then they started to recover slowly, reaching normal values 150 min later. Changes in ESP and tactile sensation were closely related. Decreases in amplitude to 90%, 80%, 60% of the control values were observed for hypesthesia, analgesia, and anesthesia, respectively. We conclude that the spinal cord also is an important site of action of epidural anesthesia.
Tabo
E
E
Department of Anesthesiology, Sumitomo Bessi Hospital, Niihama.
Ohkuma
Y
Y
Shimizu
I
I
Nagaro
T
T
Arai
T
T
D000767:Anesthesia, Epidural; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008012:Lidocaine; D008297:Male; D008875:Middle Aged; D013116:Spinal Cord / Q000502:physiology*; D014110:Touch / Q000502:physiology
D008012:Lidocaine