BACKGROUNDRopivacaine and levobupivacaine have been introduced into obstetric analgesic practice with the proposed advantages of causing less motor block and toxicity compared with bupivacaine. However, it is still controversial whether both anesthetics are associated with any clinical benefit relative to bupivacaine for labor analgesia. This study aimed to compare the analgesic efficacy, motor block and side effects of bupivacaine, ropivacaine and levobupivacaine at lower concentrations for patient-controlled epidural labor analgesia.

METHODSFour hundred and fifty nulliparous parturients were enrolled in this randomized clinical trial. A concentration of 0.05%, 0.075%, 0.1%, 0.125% or 0.15% of either bupivacaine (Group B), ropivacaine (Group R) or levobupivacaine (Group L) with sufentanil 0.5 microg/ml was epidurally administered by patient-controlled analgesia mode. Effective analgesia was defined as a visual analogue scale score was

RESULTSThere were no significant differences among groups in the numbers of effective analgesia, pain scores, hourly local anesthetic amount used, sensory and motor blockade, labor duration and mode of delivery, side effects and maternal satisfaction (P>0.05). The relative median potency was bupivacaine/ropivacaine: 0.828 (0.602-1.091), bupivacaine/levobupivacaine: 0.845 (0.617-1.12), ropivacaine/levobupivacaine: 1.021 (0.774-1.354), respectively. However, a significantly less number of effective analgesia and higher hourly local anesthetic use were observed in the concentration of 0.05% than those of >or=0.1% within each group (P<0.05).

CONCLUSIONSUsing patient-controlled epidural analgesia, lower concentrations of bupivacaine, ropivacaine and levobupivacaine with sufentanil produce similar analgesia and motor block and safety for labor analgesia. The analgesic efficacy mainly depends on the concentration rather than the type of anesthetics.

Adult ; Amides ; therapeutic use ; Analgesia, Epidural ; methods ; Analgesia, Obstetrical ; methods ; Analgesia, Patient-Controlled ; methods ; Anesthetics, Local ; therapeutic use ; Bupivacaine ; analogs & derivatives ; therapeutic use ; Female ; Humans ; Labor Pain ; drug therapy ; Labor, Obstetric ; Pregnancy ; Sufentanil ; therapeutic use ; Young Adult

BACKGROUNDIntrathecal anesthesia is commonly used for cesarean section. Bupivacaine and ropivacaine have all been used as intrathecal drugs. The minimum effective local anesthetic dose (MLAD) of intrathecal ropivacaine for non-obstetric patients has been reported. However, few data are available on the MLAD of hyperbaric ropivacaine for obstetric patients and the relative potency to bupivacaine has not been fully determined. In this study, we sought to determine the MLAD of intrathecal ropivacaine and bupivacaine for elective cesarean section and to define their relative potency ratio.

METHODSWe enrolled forty parturients undergoing elective cesarean section under combined spinal-epidural anesthesia and randomized them to one of two groups to receive intrathecal 0.5% hyperbaric ropivacaine or bupivacaine. The initial dose was 10 mg, and was increased in increments of 1 mg, using the technique of up-down sequential allocation. Efficacy was accepted if adequate sensory dermatomal anesthesia to pin prick to T7 or higher was attained within 20 minutes after intrathecal injection, and required no supplementary epidural injection for procedure until at least 50 minutes after the intrathecal injection.

RESULTSThe intrathecal MLAD was 9.45 mg (95%confidence interval (CI), 8.45 - 10.56 mg) for ropivacaine and 7.53 mg (95%CI, 7.00 - 8.10 mg) for bupivacaine. The relative potency ratio was 0.80 (95%CI, 0.74 - 0.85) for ropivacaine/bupivacaine when given intrathecally in cesarean section.

CONCLUSIONRopivacaine is 20% less potent than bupivacaine during intrathecal anesthesia for cesarean delivery.

Adult ; Amides ; administration & dosage ; therapeutic use ; Anesthetics, Local ; Bupivacaine ; administration & dosage ; therapeutic use ; Cesarean Section ; methods ; Female ; Humans ; Injections, Spinal ; Pregnancy ; Young Adult

PURPOSE: Pain in terminal cancer patients may be refractory to systemic analgesics or associated with adverse drug reactions to analgesics. Epidural analgesia has been effectively used in such patients for pain control. However, this method does not provide pain relief to all patients. The efficacy and complications of continuous epidural analgesia were evaluated for expanding efficacy in terminal cancer patients. MATERIALS AND METHODS: The charts of patients who received epidural analgesia for over 5 years for the control of terminal cancer pain were reviewed retrospectively. RESULTS: Ninety-six patients received 127 epidural catheters. The mean duration for epidural catheterization was 31.5+/-55.6 (5-509) days. The dose of epidural morphine increased by 3.5% per day. The efficacy of epidural analgesia at 2 weeks follow up revealed improved pain control (n=56), as the morphine equivalent drug dose dropped from 213.4 mg/day to 94.1 mg/day (p<0.05) at 2 weeks follow up. Accordingly, after 2 weeks institution of epidural analgesia, there was a significant reduction in the proportion of patients with severe pain, from 78.1% to 19.6% (p<0.05). CONCLUSION: Epidural analgesia was an effective pain control method in patients with terminal cancer pain, however, a systematized algorithm for the control of cancer-related pain in needed.
Adult ; Analgesia, Epidural/*methods ; Bupivacaine/therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Morphine/therapeutic use ; Neoplasms/*physiopathology ; Pain/*drug therapy ; Retrospective Studies

PURPOSE: Intravenous lipid emulsions have been used to treat the systemic toxicity of local anesthetics. The goal of this in vitro study was to examine the effects of lipid emulsions on the norepinephrine-mediated reversal of vasodilation induced by high doses of levobupivacaine, ropivacaine, and mepivacaine in isolated endothelium-denuded rat aorta, and to determine whether such effects are associated with the lipid solubility of local anesthetics. MATERIALS AND METHODS: The effects of lipid emulsions (0.30, 0.49, 1.40, and 2.61%) on norepinephrine concentration-responses in high-dose local anesthetic (6x10-4 M levobupivacaine, 2x10-3 M ropivacaine, and 7x10-3 M mepivacaine)-induced vasodilation of isolated aorta precontracted with 60 mM KCl were assessed. The effects of lipid emulsions on local anesthetic- and diltiazem-induced vasodilation in isolated aorta precontracted with phenylephrine were also assessed. RESULTS: Lipid emulsions (0.30%) enhanced norepinephrine-induced contraction in levobupivacaine-induced vasodilation, whereas 1.40 and 2.61% lipid emulsions enhanced norepinephrine-induced contraction in both ropivacaine- and mepivacaine-induced vasodilation, respectively. Lipid emulsions (0.20, 0.49 and 1.40%) inhibited vasodilation induced by levobupivacaine and ropivacaine, whereas 1.40 and 2.61% lipid emulsions slightly attenuated mepivacaine (3x10-3 M)-induced vasodilation. In addition, lipid emulsions attenuated diltiazem-induced vasodilation. Lipid emulsions enhanced norepinephrine-induced contraction in endothelium-denuded aorta without pretreatment with local anesthetics. CONCLUSION: Taken together, these results suggest that lipid emulsions enhance the norepinephrine-mediated reversal of local anesthetic-induced vasodilation at toxic anesthetic doses and inhibit local anesthetic-induced vasodilation in a manner correlated with the lipid solubility of a particular local anesthetic.
Amides/adverse effects ; Anesthetics, Local/*adverse effects ; Animals ; Bupivacaine/adverse effects/analogs & derivatives ; Emulsions/*chemistry/*therapeutic use ; Lipids/*chemistry ; Male ; Mepivacaine/adverse effects ; Norepinephrine/*therapeutic use ; Rats ; Rats, Sprague-Dawley ; Vasodilation/*drug effects

PURPOSE: Total knee replacement is one of the most painful orthopedic procedures, and effective pain relief is essential for early mobility and discharge from hospital. The aim of this study was to evaluate whether addition of single-injection femoral nerve block to epidural analgesia would provide better postoperative pain control, compared to epidural analgesia alone, after total knee replacement. MATERIALS AND METHODS: Thirty-eight patients received a single-injection femoral nerve block with 0.25% levobupivacaine (30 mL) combined with epidural analgesia (femoral nerve block group) and 40 patients received epidural analgesia alone (control group). Pain intensity and volume of patient-controlled epidural analgesia medication and rescue analgesic requirements were measured in the first 48 hours after surgery at three time periods; 0-6 hours, 6-24 hours, and 24-48 hours. Also, side effects such as nausea, vomiting, and pruritus were evaluated. RESULTS: Median visual analog scale at rest and movement was significantly lower until 48 hours in the femoral nerve block group. Patient-controlled epidural analgesia volume was significantly lower throughout the study period, however, rescue analgesia requirements were significantly lower only up to 6 hours in the femoral nerve block group. The incidences of nausea and vomiting and rescue antiemetic requirement were significantly lower in the femoral nerve block group up to 6 hours. CONCLUSION: The combination of femoral nerve block with epidural analgesia is an effective pain management regimen in patients undergoing unilateral total knee replacement.
Aged ; Analgesia, Epidural/*methods ; Analgesia, Patient-Controlled/*methods ; Anesthetics, Local/administration & dosage/therapeutic use ; Arthroplasty, Replacement, Knee/*methods ; Bupivacaine/administration & dosage/analogs & derivatives/therapeutic use ; Female ; Femoral Nerve/*drug effects ; Humans ; Injections ; Male ; Middle Aged ; Nerve Block/*methods

BACKGROUNDSpinal anesthesia was considered as a reasonable anesthetic option in severe preeclampsia when cesarean delivery is indicated, and there is no indwelling epidural catheter or contraindication to spinal anesthesia. However, the ideal dose of intrathecal bupivacaine has not been quantified for cesarean delivery for severe preeclamptic patients. This study aimed to determine the ED 50 and ED 95 of intrathecal bupivacaine for severely preeclamptic patients undergoing elective cesarean delivery.

METHODSTwo hundred severely preeclamptic patients are undergoing elective cesarean delivery under combined spinal-epidural anesthesia enrolled in this randomized, double-blinded, dose-ranging study. Patients received 4 mg, 6 mg, 8 mg, or 10 mg intrathecal hyperbaric bupivacaine with 2.5 μg sufentanil. Successful spinal anesthesia was defined as a T6 sensory level achieved within 10 minutes after intrathecal drug administration and/or no epidural supplement was required during the cesarean section. The ED 50 and ED 95 were calculated with a logistic regression model.

RESULTSED 50 and ED 95 of intrathecal bupivacaine for successful spinal anesthesia were 5.67 mg (95% confidence interval [CI]: 5.20-6.10 mg) and 8.82 mg (95% CI: 8.14-9.87 mg) respectively. The incidence of hypotension in Group 8 mg and Group 10 mg was higher than that in Group 4 mg and Group 6 mg (P < 0.05). The sensory block was significantly different among groups 10 minutes after intrathecal injection (P < 0.05). The use of lidocaine in Group 4 mg was higher than that in other groups (P < 0.05). The use of phenylephrine in Group 8 mg and Group 10 mg was higher than that in the other two groups (P < 0.05). The lowest systolic blood pressure before the infant delivery of Group 8 mg and Group 10 mg was lower than the other two groups (P < 0.05). The satisfaction of muscle relaxation in Group 4 mg was lower than other groups (P < 0.05). There was no significant difference in patients' satisfaction and the newborns' Apgar score and the blood gas analysis of umbilical artery serum (P > 0.05).

CONCLUSIONOur study showed that the ED 50 and ED 95 of intrathecal bupivacaine for severely preeclamptic patients undergoing elective cesarean delivery were 5.67 mg and 8.82 mg, respectively. In addition, decreasing the dose of intrathecal bupivacaine could reduce the incidence of maternal hypotension.

Adult ; Anesthesia, Epidural ; Anesthesia, Spinal ; adverse effects ; methods ; Blood Pressure ; physiology ; Bupivacaine ; administration & dosage ; adverse effects ; therapeutic use ; Cesarean Section ; Double-Blind Method ; Female ; Humans ; Male ; Sufentanil ; administration & dosage ; adverse effects ; therapeutic use

BACKGROUNDOur previous in vivo study in the rat demonstrates that Shenfu injection, a clinically used extract preparation from Chinese herbs, attenuates neural and cardiac toxicity induced by intravenous infusion of bupivacaine, a local anesthetic. This study was designed to investigate whether bupivacaine could induce a toxic effect in primary cultured mouse spinal cord neuron and if so, whether the Shenfu injection had a similar neuroprotective effect in the cell model.

METHODSThe spinal cords from 11- to 14-day-old fetal mice were minced and incubated. Cytarabine was added into the medium to inhibit the proliferation of non-neuronal cells. The immunocytochemical staining of beta-tubulin was used to determine the identity of cultured cells. The cultured neurons were randomly assigned into three sets treated with various doses of bupivacaine, Shenfu and bupivacaine + Shenfu, for 48 hours respectively. Cell viability in each group was analyzed by methyl thiazoleterazolium (MTT) assay.

RESULTSThe viability of the cultured neurons treated with bupivacaine at concentrations of 0.01%, 0.02%, 0.04% and 0.08% was decreased in a dose-dependent manner. Although the Shenfu injection at concentrations ranging from 1/50 to 1/12.5 (V/V) had no significant influence on the viability of cultured neurons (P < 0.05 vs control), the injection significantly increased the cellular viability of cultured neurons pretreated with 0.03% bupivacaine (P < 0.05).

CONCLUSIONAlthough Shenfu injection itself has no effect on spinal neurons, it was able to reduce the bupivacaine-induced neurotoxicity in vitro.

Anesthetics, Local ; toxicity ; Animals ; Bupivacaine ; toxicity ; Cell Survival ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Injections ; Mice ; Neurons ; drug effects ; Spinal Cord ; cytology ; drug effects