Journal of neurosurgical anesthesiology
-
J Neurosurg Anesthesiol · Oct 2009
Systemic lidocaine inhibits remifentanil-induced hyperalgesia via the inhibition of cPKCgamma membrane translocation in spinal dorsal horn of rats.
Remifentanil is being used increasingly as one component of total intravenous anesthesia. Severe postoperative pain has occasionally been reported with discontinuation of remifentanil. This study was designed to determine the involvement of conventional protein kinase Cgamma (cPKCgamma) in the inhibitory action of lidocaine on remifentanil-induced hyperalgesia of rats after propofol-remifentanil-based anesthesia. ⋯ After plantar incision, the withdrawal threshold on both the contralateral and the ipsilaeral side at 30, 120, and 300 minutes postanesthesia in group R was significantly lower than in groups P, RL, and L (P<0.05). Both immunoblotting and immunofluorescence showed that cPKCgamma membrane translocation increased in dorsal horn neurons of propofol-remifentanil-based anesthetized rats, which could be inhibited by systemic lidocaine. These results suggested that increased cPKCgamma membrane translocation was involved in remifentanil-induced hyperalgesia, which was inhibited by systemic lidocaine and may contribute to reduced postoperative pain in rats after propofol-remifentanil-based anesthesia.
-
Quadriplegic patients pose difficulty for neuromuscular monitoring owing to nonavailability of accessible normal muscle. It is known that train of four responses (T4/T1 ratio) was exaggerated in paretic limbs. However, no studies have quantified the exaggeration at different degrees of block. ⋯ There was a statistically significant difference in the train of four responses between normal and paretic limbs at all levels of block except at T4/T1 81-90. There was a significant positive correlation between difference in the T4/T1 ratio between the upper and lower limbs and intensity of block in the paraplegic group but no correlation in the normal group. The observation that T4/T1 ratio enhancement in denervated limbs is dependent on depth of neuromuscular block may have future implications for monitoring and reversal of neuromuscular block in this patient population.
-
J Neurosurg Anesthesiol · Oct 2009
Randomized Controlled TrialOral clonidine attenuates the fall in mean arterial pressure due to scalp infiltration with epinephrine-lidocaine solution in patients undergoing craniotomy: a prospective, randomized, double-blind, and placebo controlled trial.
Scalp infiltration with epinephrine-lidocaine solution in patients undergoing neurosurgery may result in transient but significant hypotension. We investigated whether premedication with alpha2-adrenoreceptor agonist clonidine, which also exhibits alpha1-adrenoreceptor mediated vasoconstriction, would prevent or attenuate this fall in mean arterial pressure (MAP). ⋯ In conclusion, oral clonidine 3 microg/kg administered 90 minutes before induction of anesthesia attenuates the fall in MAP due to scalp infiltration with a dilute concentration of epinephrine-lidocaine solution in patients undergoing craniotomy under isoflurane anesthesia.