Ropivacaine 2 mg/mL vs. bupivacaine 1.25 mg/mL with sufentanil using patient-controlled epidural analgesia in labour

Comparative Efficacy of Minimal Concentration of Racemic Bupivacaine (0.0625%) with Fentanyl and Ropivacaine (0.1%) with Fentanyl for Epidural Labor Analgesia

Background and Aims:

This study aims to compare the minimum effective concentration of local anesthetic (LA) bupivacaine and ropivacaine with highly lipid soluble opioids fentanyl for providing optimal labor epidural analgesia.

Settings and Design:

The objective of this study was to evaluate the efficacy of racemic bupivacaine 0.0625% and 0.1% of ropivacaine both mixed with 2 μg/ml of fentanyl for epidural labor analgesia in parturients with spontaneous labor and normal fetal heart rate tracing.

Methodology:

Sixty parturients requesting for labor analgesia were divided into two groups. Group B (n = 30) received racemic bupivacaine (0.0625%) and fentanyl 2 μg/ml of 10 ml and Group R (n = 30) received ropivacaine (0.1%) and fentanyl 2 μg/ml. In both groups, the drug was given in 5 ml fractionated doses at 5 min interval. Parturients not experiencing analgesia within 15 min of initial bolus were supplemented with additional 5 ml of the same concentration of the solution. Epidural analgesia was maintained by timed top ups at the end of 90 min with the dosage equal to the initial dose of the drug. Duration of labor analgesia, motor block, visual analog scale, maternal hemodynamic parameters, mode of delivery, and maternal satisfaction was assessed.

Statistical Analysis:

Data were analyzed with odds variance, unpaired t-test, and Chi-square tests. P < 0.05 was considered statistically significant.

Results:

In our study, results indicate that both drugs were equally effective clinically. Maternal demographic characteristics were comparable. There were no statistically significant differences in visual analog pain score, highest sensory block, maternal satisfaction, mode of delivery, total dose of LAs during labor and motor block at delivery between the groups.

Conclusions:

In our study, both the drugs produced equivalent analgesia for labor at low concentration when used with highly lipid soluble opioid such as fentanyl.

Efficacy and safety of local anesthetics bupivacaine, ropivacaine and levobupivacaine in combination with sufentanil in epidural anesthesia for labor and delivery: a meta-analysis

BACKGROUND

In epidural analgesia, synthetic opioids increase the potency of amide local anesthetics by modifying their analgesic properties. The purpose of this systematic review and meta-analysis is to compare the efficacy and safety of bupivacaine with ropivacaine and levobupivacaine in combination with sufentanil (BUPI-, ROPI-, and LBUPI-SUF respectively) in epidural analgesia for labor.

METHODS

A literature search was made in multiple electronic databases for original research papers published between 1995 and 2014. Meta-analyses were based on mean differences between the groups as well as odds ratios where appropriate. Both the fixed effects and random effects models were utilized and heterogeneity was tested with the I(2) index.

RESULTS

Analgesia duration was significantly longer in ROPI-SUF and LBUPI-SUF than in BUPI-SUF administered women with a mean difference (95% CI) of 16.12 (2.56, 29.68); P < 0.03 and 18.02 (9.09, 26.96); P < 0.0001 respectively under a random effects model (REM). Effective analgesia achievement was significantly earlier in the BUPI-SUF than in either the ROPI-SUF (2.61 [1.87, 3.36]; P < 0.00001) or the LBUPI-SUF groups (4.53 [3.66, 5.40]; P < 0.00001) under a fixed effects model (FEM) but not under a REM (I(2 )= 85%). Motor blockade incidence was higher in BUPI-SUF anesthetized patients, although the difference was not statistically significant. A higher incidence of instrumental deliveries was evident in the ROPI-SUF (FEM: 1.68 [1.13, 2.50]; P < 0.02/REM: 1.76 [1.00, 3.11]; P = 0.05) and LBUPI-SUF (FEM: 2.03 [1.07, 3.86]; P < 0.04/REM: 2.03 [1.07, 3.86]; P < 0.04) groups than in the BUPI-SUF group of patients. Inconsistencies in the availability of parametric data and use of slightly varying anesthetic dosages in included studies were important limitations.

CONCLUSION

Whereas significantly longer labor analgesia can be achieved with ROPI-SUF and LBUPI-SUF and ropivacaine is associated with comparatively less motor blockade, labor duration after epidural analgesia has been found to be shorter in BUPI-SUF and there is a low incidence of instrumental delivery.

Epidural ropivacaine -- where are the benefits? A prospective, randomized, double-blind trial in patients with retropubic prostatectomy

BACKGROUND

In comparison with bupivacaine, ropivacaine exhibits comparable anaesthetic effects but with less motor impairment and systemic toxicity. However, the analgesic potency may differ. For example, ropivacaine during obstetric epidural analgesia provides an approximately 40% lower analgesic potency than bupivacaine. Equal visual analogue pain scores require significantly higher dosages of ropivacaine, and general statements about a favourable benefit-risk profile relative to that of bupivacaine may therefore have limited clinical impact. We addressed this topic in a male pain model by evaluating the analgesic efficacy of epidural ropivacaine 0.2% vs. bupivacaine 0.125% after retropubic prostatectomy.

METHODS

Forty patients scheduled for retropubic prostatectomy were randomly assigned to two groups (20 patients per group). In a double-blind prospective design, patient-controlled lumbar epidural analgesia was provided by ropivacaine 0.2% in the ropivacaine group and by bupivacaine 0.125% in the bupivacaine group. The primary endpoint was the total amount of local anaesthetic consumption. The secondary endpoints were the numeric rating scale scores for rest and dynamic pain and the degree of motor impairment.

RESULTS

Ropivacaine consumption was 60% higher (mean +/- standard deviation, 1372.5 +/- 108.3 mg) than that of bupivacaine (852 +/- 75.2 mg) (P < 0.001). There were no significant differences in the numeric rating scale scores and motor impairment.

CONCLUSIONS

In male patients, lumbar epidural administration of ropivacaine 0.2% after retropubic prostatectomy does not appear to provide benefits over bupivacaine 0.125%. Moreover, in view of the significantly higher drug requirements, general statements focusing on the favourable therapeutic index of ropivacaine may require critical analysis, at least during epidural administration.

Recent developments in patient-controlled analgesia

Patient-controlled analgesia (PCA) has become the gold standard for acute pain management since it was first introduced 20 years ago, and its merits have been discussed in quite a large number of publications. This review summarizes the more recent developments, such as new application devices and strategies, including intranasal, spinal, and regional PCA; patient-controlled sedation; experience with children and elderly people; and some data from chronic pain situations. Analyzing PCA literature from 2001 onwards confirms the author's long belief that the PCA principle ("WYNIWYG": what you need is what you get) was the most important aspect of a patient-controlled strategy, more or less independent of the type of drug or machine. Discovering this principle has changed the understanding of pain and suffering.

Evolving spinal analgesia practice in palliative care

Intraspinal analgesia can be helpful in some patients with intractable pain. Over 15 years palliative care professionals evolved their spinals policy through a repeated series of evaluations, discussions and literature reviews. One hundred intraspinal lines were then reviewed. Notable changes in policy were the switch from epidurals to intrathecals, and the insertion of lines during working hours rather than as emergencies. Our efficacy, and frequency of adverse effects, is equal or better to published studies. Key issues in reducing adverse effects were the improved care of the spinal line exit site, a change from bolus administration to continuous infusions, and modifying line insertion techniques. Current policy is to use continuous infusions of diamorphine and bupivacaine in a 1:5 ratio through externalized intrathecal lines. The lines are effective in approximately two thirds of patients and can be kept in place for up to 18 months. The policy continues to be updated and common documentation is now in place.

Benefit-Risk Assessment of Ropivacaine in the Management of Postoperative Pain

Ropivacaine is a long-acting amide-type local anaesthetic, released for clinical use in 1996. In comparison with bupivacaine, ropivacaine is equally effective for subcutaneous infiltration, epidural and peripheral nerve block for surgery, obstetric procedures and postoperative analgesia. Nevertheless, ropivacaine differs from bupivacaine in several aspects: firstly, it is marketed as a pure S(-)-enantiomer and not as a racemate, and secondly, its lipid solubility is markedly lower. These features have been suggested to significantly improve the safety profile of ropivacaine, and indeed, numerous studies have shown that ropivacaine has less cardiovascular and CNS toxicity than racemic bupivacaine in healthy volunteers. Extensive clinical data have demonstrated that epidural 0.2% ropivacaine is nearly identical to 0.2% bupivacaine with regard to onset, quality and duration of sensory blockade for initiation and maintenance of labour analgesia. Ropivacaine also provides effective pain relief after abdominal or orthopaedic surgery, especially when given in conjunction with opioids or other adjuvants. Nevertheless, epidurally administered ropivacaine causes significantly less motor blockade at low concentrations. Whether the greater degree of blockade of nerve fibres involved in pain transmission (Adelta- and C-fibres) than of those controlling motor function (Aalpha- and Abeta-fibres) is due to a lower relative potency compared with bupivacaine or whether other physicochemical properties or stereoselectivity are involved, is still a matter of intense debate. Recommended epidural doses for postoperative or labour pain are 20-40 mg as bolus with 20-30 mg as top-up dose, with an interval of >or=30 minutes. Alternatively, 0.2% ropivacaine can be given as continuous epidural infusion at a rate of 6-14 mL/h (lumbar route) or 4-10 mL/h (thoracic route). Preoperative or postoperative subcutaneous wound infiltration, during cholecystectomy or inguinal hernia repair, with ropivacaine 100-175 mg has been shown to be more effective than placebo and as effective as bupivacaine in reducing wound pain, whereby the vasoconstrictive potency of ropivacaine may be involved. Similar results were found in peripheral blockades on upper and lower limbs. Ropivacaine shows an identical efficacy and potency to that of bupivacaine, with similar analgesic duration over hours using single shot or continuous catheter techniques. In summary, ropivacaine, a newer long-acting local anaesthetic, has an efficacy generally similar to that of the same dose of bupivacaine with regard to postoperative pain relief, but causes less motor blockade and stronger vasoconstriction at low concentrations. Despite a significantly better safety profile of the pure S(-)-isomer of ropivacaine, the increased cost of ropivacaine may presently limit its clinical utility in postoperative pain therapy.

Obstetric epidural analgesia

PURPOSE OF THE REVIEW

There has recently been a growing interest in developing and modulating the techniques of neuraxial analgesia to meet the changing individual needs of parturients for pain relief during the course of labour and delivery.

RECENT FINDINGS

Neuraxial analgesia is now very safe. Modern low-dose spinal-epidural regimens provide efficacious analgesia, stable maternal haemodynamics and few tolerable side effects. Complications are possible, however, due to the invasive nature of the technique, patient characteristics or medical malpractice.

SUMMARY

Labour epidural analgesia still remains the 'gold standard' of obstetric pain management, although spinal analgesia with the single-injection technique is an attractive option due to its simplicity, reliability and efficacy. Up till now, there has been no single new drug to overcome the superiority of neuraxial analgesia in obstetrics.