Regional anesthesia and pain medicine
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Reg Anesth Pain Med · Mar 2000
Comparative StudyRopivacaine attenuates pulmonary vasoconstriction induced by thromboxane A2 analogue in the isolated perfused rat lung.
Thromboxane A2 (TXA2) activation is involved in several pathophysiological states in producing pulmonary hypertension. Local anesthetics (LA) inhibit signaling of TXA2 receptors expressed in cell models. Therefore, we hypothesized that LA may inhibit pulmonary vasoconstriction induced by the TXA2 analogue U 46619 in an isolated lung model. ⋯ Ropivacaine, but not lidocaine, bupivacaine, or QX 314 at 1 microg/mL, attenuates U 46619-induced pulmonary vasoconstriction in an isolated perfused rat lung model. These results support evidence that the clinically used enantiomer S(-)-ropivacaine may inhibit TXA2 signaling.
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Reg Anesth Pain Med · Jan 2000
Randomized Controlled Trial Comparative Study Clinical TrialSupraspinal pupillary effects of intravenous and epidural fentanyl during isoflurane anesthesia.
Epidural fentanyl has been shown to gain rapid access to the circulation resulting in supraspinal effects. We compared the supraspinal effects of fentanyl via epidural versus intravenous (IV) routes, during isoflurane anesthesia. Supraspinal fentanyl effect was evaluated as a reduction of pupillary reflex dilation (PRD) measured with infrared pupillometry. ⋯ Supraspinal effects of epidural fentanyl can be assessed during general anesthesia using infrared pupillometry. Epidural fentanyl 3 microg/kg produces significant but variable supraspinal effects during 0.5 minimum alveolar concentration isoflurane anesthesia.
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Reg Anesth Pain Med · Jan 2000
Randomized Controlled Trial Clinical TrialEvaluation of efficacy and plasma concentrations of ropivacaine in continuous axillary brachial plexus block: high dose for surgical anesthesia and low dose for postoperative analgesia.
Ropivacaine is a potent local anesthetic that, experimentally at low concentrations, produces an effective block of pain conducting nerve fibers. Therefore, it was hypothesized that 0.1% and 0.2% ropivacaine would provide clinically adequate postoperative analgesia in continuous axillary plexus block. ⋯ Ropivacaine is safe and effective for axillary brachial plexus block. The continuous infusion of 0.1% or 0.2% ropivacaine was no more beneficial than an infusion of saline in relieving postoperative pain in patients having elective hand surgery. None of the infusions were sufficient to adequately treat the patients' pain without the addition of adjunct agents.