Anesthesia and analgesia
-
Anesthesia and analgesia · Dec 2000
Block of neuronal tetrodotoxin-resistant Na+ currents by stereoisomers of piperidine local anesthetics.
Tetrodotoxin (TTX)-sensitive Na(+) channels in the peripheral nervous system are the major targets for local anesthetics. In the peripheral nociceptive system, a Na(+) channel subtype resistant to TTX and with distinct electrophysiological properties seems to be of importance for impulse generation and conduction. A current through TTX-resistant Na(+) channels displays slower activation and inactivation kinetics and has an increased activation threshold compared with TTX-sensitive Na(+) currents and may have different pharmacological properties. ⋯ Potencies for tonic and for use-dependent block increased with rising lipid solubilities of the drugs. Stereoselective action was not observed. We conclude that block of TTX-resistant Na(+) currents may lead to blockade of TTX-resistant action potentials in nociceptive fibers and consequently may be responsible for pain suppression during local anesthesia.
-
Anesthesia and analgesia · Dec 2000
Randomized Controlled Trial Clinical TrialThe use of bupivacaine and fentanyl for spinal anesthesia for urologic surgery.
We evaluated the effect of 25 microg of fentanyl added to bupivacaine on sensory and motor block. By using a double-blinded study design, 80 men undergoing urologic surgery were randomized into the following four groups: Group I, bupivacaine 10 mg; Group II, bupivacaine 10 mg + fentanyl 25 microg; Group III, bupivacaine 7.5 mg + fentanyl 25 microg; Group IV, bupivacaine 5 mg + fentanyl 25 microg. The final volume of intrathecal injectate was adjusted to 2. 5 mL with sterile distilled water. ⋯ The addition of 25 microg of fentanyl to 5 mg of bupivacaine resulted in short-acting motor block. When 25 microg of fentanyl was added to 10 mg of bupivacaine, it increased the intensity and duration of motor block. Only 5 (6. 3%) of the patients needed supplemental analgesia during the operation. ¿abs¿
-
Anesthesia and analgesia · Dec 2000
Randomized Controlled Trial Clinical TrialThe analgesic efficacy of patient-controlled ropivacaine instillation after Cesarean delivery.
To assess the efficacy and safety of wound instillation of ropivacaine, when administered via a patient-controlled elastometric pump, 50 term parturients undergoing cesarean delivery were enrolled into this prospective, placebo-controlled, double-blinded study. In all cases, a standard spinal anesthetic was administered. After the surgery, a multihole 20-gauge epidural catheter (B. ⋯ However, blood ropivacaine accumulation was noted. All patients stated that the elastometric pump was easy to use. Ropivacaine wound instillation via an elastometric pump is a simple technique that provides safe and effective analgesia after cesarean delivery.
-
Anesthesia and analgesia · Dec 2000
Randomized Controlled Trial Clinical TrialThe efficacy of intrathecal morphine and clonidine in the treatment of pain after spinal cord injury.
We performed a double-blinded, randomized, controlled trial in 15 patients to determine the efficacy of intrathecal morphine or clonidine, alone or combined, in the treatment of neuropathic pain after spinal cord injury. The combination of morphine and clonidine produced significantly more pain relief than placebo 4 h after administration; either morphine or clonidine alone did not produce as much pain relief. In addition, lumbar and cervical cerebrospinal fluid (CSF) concentrations, sampled at these levels at different times after administration were examined for a relationship between pain relief and CSF drug concentration. ⋯ The concentration of morphine in the cervical CSF and the degree of pain relief correlated significantly. We conclude that intrathecal administration of a mixture of clonidine and morphine is more effective than either drug administered alone and is related to the CSF-borne drug concentration above the level of spinal cord injury. If there is pathology that may restrict CSF flow, consideration should be given to intrathecal administration above the level of spinal cord damage to provide an adequate drug concentration in this region.
-
Anesthesia and analgesia · Dec 2000
Randomized Controlled Trial Clinical TrialInterscalene brachial plexus block with a continuous catheter insertion system and a disposable infusion pump.
Continuous interscalene brachial plexus blockade traditionally requires a hospital stay for local anesthetic infusion, and achieving consistent catheter insertion may be difficult. Incorporating long-acting pain relief from a continuous peripheral nerve block, with a reliable method of catheter insertion, and a self-contained infusion system would be a valuable asset for short-stay care. We compared the efficacy of single injection interscalene brachial plexus blockade to a continuous peripheral nerve block, with an insulated Tuohy system and a disposable infusion pump. ⋯ In addition, initial interscalene blockade was successful in all patients and all redosed catheters were functional after 24 h with the continuous catheter insertion system. We conclude that it is possible to achieve a high rate of successful catheter placement and analgesia by using the continuous catheter insertion system and a disposable infusion pump in the ambulatory setting. This method of analgesia may offer improved pain relief after outpatient rotator cuff repair.