Effects of epidural fentanyl on speed and quality of block for emergency cesarean section in extending continuous epidural labor analgesia using ropivacaine and fentanyl

Comparison of median effective concentration of ropivacaine in multiparas or primiparas during epidural labor analgesia: STROBE compliant

The documents on the median effective concentration of local analgesic were many in primiparas during labor analgesia. However, the studies were fewer in multiparas. To explore the analgesic requirements in multiparas during epidural labor analgesia, we investigated the median effective concentration of ropivacaine with 2 μg/mL fentanyl for epidural labor analgesia in multiparas.Sixty-two women were recruited and assigned to the primipara group and multipara group in this prospective study. All the parturients received ropivacaine combined with 2 μg/mL fentanyl for epidural labor analgesia. The concentration of ropivacaine was determined by the up and down method and an initial concentration was set as 0.1% with a 0.01% interval. Effective analgesia was defined as the visual analog scale (VAS) ≤3 within 30 minutes after epidural administration when cervical dilatation is about 2 cm. The median effective concentration of ropivacaine was calculated by the up and down sequential method. The pain intensity was assessed using VAS. Hemodynamic parameters, the labor stages, and neonatal Apgar scores were recorded. Umbilical artery blood was drawn to analyze. The side effects, if any, were also recorded.The median effective concentration of ropivacaine was 0.057% (95% confidence interval [CI], 0.051-0.064%) in primiparas during epidural labor analgesia, and 0.068% (95% CI, 0.063-0.072%) in multiparas during epidural labor analgesia, there was significant difference between the groups (P = .02).This study indicated that the median effective concentration of ropivacaine with fentanyl for epidural labor analgesia was 0.068% (95% CI, 0.063-0.072%) and increased in multiparas compared with the primiparas (www.chictr.org.cn, registration number: ChiCTR-1800016486).

Comparing Different Epinephrine Concentrations for Spinal Anesthesia in Cesarean Section: A Double-Blind Randomized Clinical Trial

BACKGROUND

Although various anesthetic techniques can be used in different kinds of surgeries, spinal anesthesia has received considerable attention for the lower abdomen and lower extremities surgeries and cesarean section. This study aimed at comparing the effect of adding epinephrine 1:1000 and 1:10000 to lidocaine and fentanyl in spinal anesthesia on the prolongation of paralysis, analgesia and hemodynamic changes in pregnant women candidate for cesarean section.

METHODS

A double blind randomized clinical trial was carried out on 66 pregnant women (equally sized control and treatment groups of 33) in 2011. After randomizing the participants into two groups of recipients of epinephrine 1:1000 plus lidocaine 5% and fentanyl (control group) and recipients of epinephrine 1:10000 with lidocaine 5% and fentanyl, (treatment group), the participants' systolic and diastolic blood pressure and heart rate were recorded before and 1, 3, 5, 10, 15 minutes after procedure. Besides the prolongation of paralysis and analgesia, the presence of postoperative nausea and vomiting were evaluated. The outcome of the study was analyzed using SPSS software and via t test, χ2 test and RMANOVA.

RESULTS

The mean age (standard deviation) of the participants was 29.3 (4.4) and 28.2 (4.5) in the treatment and control groups, respectively. There were no statistical significance between the participants' prolongation of paralysis, analgesia, the frequency of nausea and vomiting, and the average values of hemodynamic variables between the two groups.

CONCLUSION

The use of epinephrine 1:10000 along with lidocaine and fentanyl is recommended in spinal anesthesia in pregnant women candidate for cesarean section.

TRIAL REGISTRATION NUMBER

IRCT201012225445N1.

The effect of addition of low dose fentanyl to epidural bupivacaine (0.5%) in patients undergoing elective caesarean section: A randomized, parallel group, double blind, placebo controlled study

BACKGROUND

Opioids have synergistic action with local anesthetics which may alter characteristics of epidural block. Giving opioids to mother before delivery of baby is still fully not accepted with some fearing risk of neonatal depression.

AIMS

Our primary aim was to evaluate the analgesic effect of addition of 50 μg fentanyl to epidural 0.5% bupivacaine in patients undergoing elective caesarean section using visual analog scale. The secondary aim was to assess onset of analgesia, volume of drug required to achieve T6 level, grade and duration of motor block and Apgar score.

MATERIALS AND METHODS

In this prospective, randomized, double blind, placebo controlled study 64 patients scheduled for elective caesarean section under epidural anesthesia were randomly divided into two groups of 32 each. The fentanyl group received 1 ml of 50 μg fentanyl and the saline group received 1 ml of normal saline mixed with 10 ml of 0.5% bupivacaine for epidural anesthesia. VAS score, time to achieve T6 level, dose of bupivacaine, intraoperative analgesic consumption and duration of analgesia, grade and duration of motor block and any adverse maternal and neonatal effects were noted.

STATISTICAL ANALYSIS

Data was analyzed using Students t test, chi-square test and Mann-Whitney U-test. The values of P<0.05 were considered statistically significant.

RESULTS

Fentanyl improved the VAS score significantly (1.6±1.32) compared to the saline group (3.77±1.0, P<0.0001). It also reduced the intraoperaitve analgesic supplementation compared to the saline group. (P=0.031). The postoperative duration of analgesia was prolonged in the fentanyl group (275.80±13.61 min) compared to the saline group (191.47±12.16 min, P<0.0001). The other characteristics of epidural block were unaltered.

CONCLUSION

Addition of 50 μg fentanyl to epidural 0.5% bupivacaine significantly reduces the VAS score. It also reduces intra-operative analgesia supplementation and prolongs the duration of postoperative analgesia without altering the other characteristics of block. The neonatal outcome is not affected with addition of fentanyl before delivery of baby.

Effects of chronic fentanyl administration on physical performance of aged rats

There is growing concern over the increasing use of opioids to treat chronic pain in the elderly primarily because of the potential increased sensitivity to the adverse side effects. Here, we use a preclinical model (male Brown Norway X F344 rats aged 12, 18, 24, and 30 months) to describe the outcome of chronic fentanyl administration (1.0mg/kg/day) on various physiological and behavioral measures. Continuous fentanyl administration resulted in an initial decrease in food consumption, followed by the development of tolerance to this effect over a 4-week period and a subsequent increase in food consumption during withdrawal. This change in food consumption was associated with decreases in body weight (predominantly due to a loss of fat mass) that was maintained through early withdrawal. After 1 month of withdrawal, only the 12-month old animals had fully regained body weight. Fentanyl administration resulted in a decrease in grip strength and an increase in locomotor activity that did not differ across age groups. There was no effect of fentanyl administration on rotarod performance. These results demonstrate that while there is a delayed recovery of body mass with age, the observed changes in behavioral responses are uniform across ages.