Effects of 2% lignocaine on somatosensory evoked potentials recorded in the extradural space.
We have studied the effects of extradural administration of 2% lignocaine at the L3-4 interspace on somatosensory evoked potentials recorded in the cervical extradural space before corrective surgery for idiopathic adolescent scoliosis. Eight patients in whom the equivalent volume of 0.9% sodium chloride solution was administered into the lumbar extradural space acted as a control group. Lignocaine 2% resulted in a decrease in overall amplitude, but its main effect was a significant decrease in the amplitude of the second and third peaks, suggesting an action on the dorsal columns of the spinal cord. A significant increase in latency was found in both the lignocaine and sodium chloride groups. We conclude that the use of extradural 2% lignocaine in patients undergoing scoliosis surgery may interfere with the intraoperative monitoring of somatosensory evoked potentials.
Loughnan
B A
BA
Department of Anaesthetics and Medical Physics, Royal National Orthopaedic Hospital, Stanmore, Middx.
Murdoch
L J
LJ
Hetreed
M A
MA
Howard
L A
LA
Hall
G M
GM
D000293:Adolescent; D000767:Anesthesia, Epidural / Q000379:methods*; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects*; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008012:Lidocaine; D008297:Male; D012600:Scoliosis / Q000601:surgery
D008012:Lidocaine