Baguley DM, Jones S, Wilkins I, Axon PR, Moffat DA (2005)
infusion of lidocaine has previously been demonstrated to have a
transient inhibitory effect on tinnitus in 60% of individuals.
of action has variously been proposed as the cochlea, the cochlea nerve,
and the central auditory pathways.
To determine whether a central site
of action exists, this study investigated the effect of intravenous
infusion of lidocaine in individuals with tinnitus who had previously
undergone translabyrinthine excision of a vestibular schwannoma, which
involves division of the cochlear nerve.
Double-blind, placebo-controlled, crossover study.
who had undergone translabyrinthine removal of a unilateral, sporadic,
and histologically proven vestibular schwannoma in the last decade and
who had reported postoperative tinnitus at follow-up were identified
from a departmental database.
Sixteen patients participated (12 men and 4
The mean age (+/- standard deviation) of the patients was 58
+/- 8.6 years, and the meantime since operation was 24.3 +/- 7.3 months.
of 2% lidocaine hydrochloride and sodium chloride 0.9% were prepared in
identical randomized vials. The volume required for 1.5 ml/kg body
weight lidocaine was calculated, and this volume was given over 5
minutes for either vial.
Blood pressure, pulse oximetry, and cardiac
monitoring were set up and performed throughout the infusions. All
investigators were blinded.
Patient-completed visual analogue
scale measures of tinnitus intensity, pitch, and distress, performed
before infusion, 5 minutes after infusion onset, and 20 minutes after
A significant difference (Wilcoxon signed-rank
test, p < 0.05) between placebo and lidocaine infusion conditions was
demonstrated for change in visual analogue scale estimates (preinfusion
versus 5 min postinfusion) of tinnitus loudness (p = 0.036), pitch (p =
0.026), and distress (p = 0.04).
No significant difference between
placebo and lidocaine infusion conditions was demonstrated for change in
visual analogue scale estimates (preinfusion versus 20 min
postinfusion) of tinnitus loudness (p = 0.066), pitch (p = 0.173), and
distress (p = 0.058).
The indication is of a short-lasting inhibitory
effect on tinnitus of lidocaine infusion compared with saline placebo in
patients who have undergone translabyrinthine excision of a vestibular
Intravenous infusion of lidocaine has a statistically
significant inhibitory effect on tinnitus in patients who have
previously undergone translabyrinthine removal of a vestibular
The site of action of lidocaine in this instance must be in
the central auditory pathway, as the cochlear and vestibular nerves are
sectioned during surgery, and this finding has important implications
for the task of identifying other agents that will have a similar
Fuente: Otol Neurotol 26(2):169-76