Journal of neurosurgical anesthesiology
-
Plasma ropivacaine levels produced by routine scalp infiltration for field block were assayed in eight patients undergoing awake intracranial surgery. Levels peaked within approximately 13 minutes, indicating rapid systemic absorption of ropivacaine. Potentially toxic plasma drug levels were achieved in three of eight patients, although no untoward effects attributable to elevated levels of ropivacaine were observed. Clinical vigilance is indicated during scalp infiltration with ropivacaine.
-
J Neurosurg Anesthesiol · Jul 2005
Randomized Controlled Trial Clinical TrialScalp infiltration with bupivacaine plus epinephrine or plain ropivacaine reduces postoperative pain after supratentorial craniotomy.
Local anesthetic infiltration has been proposed to decrease postoperative pain. The aim of this study was to determine whether scalp infiltration with bupivacaine or ropivacaine would improve analgesia after supratentorial craniotomy for tumor resection. Eighty patients were recruited into a randomized double-blind study. ⋯ The median morphine consumption up to the 16th postoperative hour was not significantly different among the 3 groups. There was no difference in the visual analogue scale scores among the 3 groups at any time. Scalp infiltration with either bupivacaine or ropivacaine had a statistically significant effect on morphine consumption during the first 2 postoperative hours.
-
J Neurosurg Anesthesiol · Jul 2005
The effect of phenytoin on rocuronium-induced neuromuscular block in the rat phrenic nerve-hemidiaphragm preparation.
Anticonvulsant therapy alters the action of nondepolarizing muscle relaxants. We determined the effects of acute and chronic administration of phenytoin on rocuronium-induced neuromuscular block using the rat phrenic nerve-hemidiaphragm preparation. Rats were divided into 3 groups: a saline control group (n = 10), an acute phenytoin-treated group (n = 30), and a chronic phenytoin-pretreated group (n = 30). ⋯ In rats with phenytoin 10 microg/mL in the bath, the effective concentrations for 50%, 90%, and 95% twitch depression values were significantly different from those of the control group (P < 0.05). In chronically (28 days) phenytoin-pretreated rats, the concentration-response curve significantly shifted to the right (P < 0.05). These findings show that acute administration of phenytoin augmented the neuromuscular blocking effects of rocuronium, whereas chronic phenytoin treatment causes resistance to the neuromuscular blocking effects of rocuronium in target organs.