Quantitative sensory examination in human epidural anaesthesia and analgesia: effects of lidocaine.
To characterize the sensory effects of epidural lidocaine, 2 groups each of 10 human subjects received 25 ml of 2% lidocaine at the L1-L2/L2-L3 interspace (high lumbar group) or at the L3-L4/L4-L5 interspace (low lumbar group). Twelve quantitative sensory tests in the L5 and S1 dermatomes and leg extension strength were determined every 30 min for 3 h. Sensory and motor blockade were more pronounced in the low than in the high lumbar group. Sensory functions were blocked in the following order by epidural lidocaine: warm > cold > electrical stimuli. Perception of brief localized noxious stimuli was attenuated more than perception of noxious stimuli of longer duration and involving larger stimulus areas. It is suggested that both peripheral mechanisms (differential conduction blockade of afferent fibres) and central mechanisms (temporal and spatial summation) play a role in the sensory effects of epidural lidocaine.
Brennum
Jannick
J
Laboratory of Sensory Physiology, Department of Neurology, Gentofte Hospital, DK-2900 HellerupDenmark Department of Anaesthesia, Rigshospitalet, DK-2100 København ØDenmark Department of Medical Informatics, Aalborg University, Frederik Bajersvej 7, DK-9100 AalborgDenmark Department of Neurology, Aarhus University Hospital, DK-8000 Aarhus CDenmark Department of Dermatology, Marselisborg Hospital, DK-8000 Aarhus C Denmark.
Arendt-Nielsen
Lars
L
Secher
Niels H
NH
Jensen
Troels S
TS
Bjerring
Peter
P
D000328:Adult; D015360:Analgesia, Epidural / Q000009:adverse effects; D000767:Anesthesia, Epidural / Q000009:adverse effects; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000009:adverse effects; D008297:Male; D017288:Pain Threshold / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects; D012684:Sensory Thresholds / Q000187:drug effects
D008012:Lidocaine