ED 50 and ED 95 of intrathecal bupivacaine coadministered with sufentanil for cesarean delivery under combined spinal-epidural in severely preeclamptic patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Spinal 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.</p><p><b>METHODS</b>Two 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.</p><p><b>RESULTS</b>ED 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).</p><p><b>CONCLUSION</b>Our 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.</p>

The Dose-response of Intrathecal Ropivacaine Co-administered with Sufentanil for Cesarean Delivery under Combined Spinal-epidural Anesthesia in Patients with Scarred Uterus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Spinal anesthesia is considered as a reasonable anesthetic option in lower abdominal and lower limb surgery. This study was to determine the dose-response of intrathecal ropivacaine in patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia.</p><p><b>METHODS</b>Seventy-five patients with scarred uterus undergoing elective cesarean delivery under combined spinal-epidural anesthesia were enrolled in this randomized, double-blinded, dose-ranging study. Patients received 6, 8, 10, 12, or 14 mg intrathecal hyperbaric ropivacaine with 5 μg sufentanil. Successful spinal anesthesia was defined as a T4sensory level achieved with no need for epidural supplementation. The 50% effective dose (ED50) and 95% effective dose (ED95) were calculated with a logistic regression model.</p><p><b>RESULTS</b>ED50and ED95of intrathecal hyperbaric ropivacaine for patients with scarred uterus undergoing cesarean delivery under combined spinal-epidural anesthesia (CSEA) were 8.28 mg (95% confidence interval [CI]: 2.28-9.83 mg) and 12.24 mg (95% CI: 10.53-21.88 mg), respectively.</p><p><b>CONCLUSION</b>When a CSEA technique is to use in patients with scarred uterus for an elective cesarean delivery, the ED50and ED95of intrathecal hyperbaric ropivacaine along with 5 μg sufentanil were 8.28 mg and 12.24 mg, respectively. In addition, this local anesthetic is unsuitable for emergent cesarean delivery, but it has advantages for ambulatory patients.</p>

Comparison of bupivacaine, ropivacaine and levobupivacaine with sufentanil for patient-controlled epidural analgesia during labor: a randomized clinical trial / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Ropivacaine 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.</p><p><b>METHODS</b>Four 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 <or=30 mm. The relative median potency for each local anesthetic was calculated using a probit regression model. Parturients demographics, sensory and motor blockade, obstetric data, maternal side effects, hourly volumes of local anesthetic used, and others were also noted.</p><p><b>RESULTS</b>There 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).</p><p><b>CONCLUSIONS</b>Using 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.</p>

An angiographic trial to evaluate the efficacy and safety of tenecteplase in Chinese patients with acute myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>In this randomized, open-label, multicenter, angiographic trial, we compared the efficacy and safety of tenecteplase (TNK-tPA) with alteplase (rt-PA) in Chinese patients with acute myocardial infarction.</p><p><b>METHOD</b>Patients with acute ST-elevation myocardial infarction and pain to hospital time within 6 hours from October 2002, to March 2004 were randomly assigned a body weight-adjusted bolus of TNK-tPA (0.53 mg/kg over more than 10 s, n = 58) or front loaded rt-PA (< or = 100 mg, n = 52). Coronary angiography was performed at 90 min after initiating study drugs. All patients received aspirin and heparin (target activated partial thromboplastin time: 50-70 s). The primary end point of the trial was the rate of TIMI grade 3 flow at 90 minutes. Other end points included the rate of TIMI grade 2/3 flow at 90 minutes, all cause mortality at 30 days, the moderate/severe hemorrhage without intracranial hemorrhage (ICH) and ICH within 30 days.</p><p><b>RESULTS</b>TIMI grade 3 flow at 90 minutes (68.4% vs. 66.7%, P = 1.00), TIMI grade 2 or 3 at 90 minutes (89.5% vs. 80.4%, P = 0.278), total mortality at 30 days (13.8% vs. 9.6%, P = 0.565), the rate of moderate/severe hemorrhage (8.6% vs. 5.8%, P = 0.72) and incidence of ICH (3.5% vs. 1.9%, P = 1.00) were all similar in TNK-tPA treated patients compared to rt-PA treated patients.</p><p><b>CONCLUSION</b>The efficacy of single-bolus, weight-adjusted TNK-tPA fibrinolytic regimen is equivalent to front-loaded alteplase in terms of the rates of TIMI grade 3 flow, TIMI 2 or 3 flow. Incidences of moderate/severe hemorrhage, ICH and 30-days mortality were similar in TNK-tPA and rt-PA treated patients.</p>

Effects of quinidine on pinacidil-induced transmural dispersion of repolarization in canine right ventricular wall / 中华心血管病杂志

<p><b>OBJECTIVE</b>On the basis that pinacidil can produce an "all or none" repolarization in right ventricular wall of canine, to observe the effects of quinidine on the marked transmural dispersion of repolarization. Recent studies have shown that ventricular myocardium is composed of at least 3 electrophysiological distinct cell types: epicardial, endocardial, and midcardial cells. Differences in the response of the 3 cell types to pharmacologic agents and/or pathophysiological states often result in amplification of intrinsic electrical heterogeneities, thus providing a substrate as well as a trigger for the development of arrhythmias. The study was designed to observe the right ventricular transmural heterogeneity in vitro canine heart tissue preparation level.</p><p><b>METHODS</b>The strips were isolated from the anterior wall of the right ventricular of canine. The preparations perfused with oxygenated (95%O(2)/5%CO(2)) Tyrode's solution. The tissues were stimulated at basic cycle lengths of 1000 ms. Standard microelectrode techniques were used. Transmembrane action potentials were recorded from epicardial, midcardial and endocardial cells respectively from right ventricular free wall of canine on different conditions [perusing with Tyrode's solution (Control), pinacidil (2.5 micromol/L), and quinidine (5 micromol/L) in turn].</p><p><b>RESULTS</b>Compared with that of endocardial cells, the action potentials of canine ventricular epicardial and midcardial cells had more obvious spike and dome morphology. Pinacidil (2.5 micromol/L) caused a loss of the dome of transmembrane action potentials and a marked abbreviation of the action potential duration (APD) in right ventricular epicardial and midcardial cells, especially in epicardial cells, but not in endocardial cells (n = 10). With pinacidil (2.5 micromol/L), in epicardial cells, phase 2 amplitude of action potentials decreased from (117.7 +/- 9.3) mV to (71.3 +/- 6.4) mV (P < 0.01), and 90% of the APD(90) decreased from (198.2 +/- 20.8) ms to (103.9 +/- 13.5) ms (P < 0.01). The transmural dispersion of action potential duration increased from (48.5 +/- 9.2) ms to (128.7 +/- 13.5) ms (P < 0.01). Quinidine (5 micromol/L) effectively prolonged the APD abbreviated by pinacidil, restored or partly restored the dome of transmembrane action potentials of epicardial and midcardial cells but not of endocardial cells (n = 10). In epicardial cells phase 2 amplitude increased from (71.3 +/- 6.4) mV to (106.6 +/- 7.7) mV (P < 0.01), and 90% of the APD(90) increased from (103.9 +/- 13.5) ms to (185.9 +/- 15.7) ms (P < 0.01). The transmural dispersion of action potential duration significantly decreased from (128.7 +/- 13.5) ms to (54.3 +/- 10.8) ms (P < 0.01). Quinidine reduced pinacidil-induced transmural dispersion of phase 2 amplitude and the APD in right ventricular wall of canine.</p><p><b>CONCLUSION</b>By restoring the dome and the APD of the epicardial and midcardial cells action potentials, quinidine (5 micromol/L) could reduce the marked transmural dispersion of repolarization caused by pinacidil.</p>