Epidural infusion of low-dose bupivacaine and opioid in labour. Does reducing motor block increase the spontaneous delivery rate?

Safety and Efficiency of Low-Dose Spinal Analgesia Compared to Epidural Analgesia in Treatment of Pain during Labour: A Case Control Study

BACKGROUND

The epidural catheter for analgesia has been used for decades and has become the gold standard in pain therapy for pregnant women in labour. However, procedural parameters such as time to pain relief and duration to implementation pose hurdles for patients shortly before delivery. Low-dose spinal analgesia (LDSA) is an alternative procedure that was investigated in the study with regard to patient satisfaction and complication rates compared to epidural catheter.

METHODS

In a retrospective monocentric study, a total of 242 patients receiving low-dose spinal analgesia or epidural catheters were evaluated using propensity score matching. Subjective patient satisfaction as well as complication rates were primarily analysed. We hypothesise that LDSA is a safe procedure and provides a similar level of satisfaction compared with the epidural catheter. For this purpose, both procedures were performed according to in-house standards and the patients were interviewed afterwards. Patients who required surgical delivery were excluded to prevent bias.

RESULTS

The LDSA was rated on average as very good [1.09 ± 0.311 vs. 1.07 ± 0.431] in terms of satisfaction by the patients compared to the epidural catheter without showing a significant difference (p = 0.653). Complications were in the low single-digit non-significant range for both procedures [6 (5%) vs. 7 (6%); p = 0.776]. The evaluation showed more perineal tears I° and II° in the low-dose spinal analgesia group [I°: 28 (23%) vs. 3 (2%); p < 0.001-II°: 30 (25%) vs. 2 (2%); p < 0.001]. Neonatal parameters differed significantly only in umbilical cord base excess and umbilical cord venous pH [-5.40 vs. -6.40; p = 0.005].

CONCLUSIONS

LDSA represents a low complication procedure for patients at the end of labour with a high satisfaction level. With the LDSA in the repertoire of pain relief during childbirth, it is possible to also achieve pain reduction for women with deliveries of high velocity without compromising patient satisfaction or perinatal morbidity.

Vaginal Birth at Term - Part 2. Guideline of the DGGG, OEGGG and SGGG (S3-Level, AWMF Registry No. 015/083, December 2020)

Purpose This guideline aims to summarize the current state of knowledge about vaginal birth at term. The guideline focuses on definitions of the physiological stages of labor as well as differentiating between various pathological developments and conditions. It also assesses the need for intervention and the options to avoid interventions. The second part of this guideline presents recommendations and statements on care during the dilation and expulsion stages as well as during the placental/postnatal stage. Methods The German recommendations largely reproduce the recommendations of the National Institute for Health and Care Excellence (NICE) CG190 guideline "Intrapartum care for healthy women and babies". Other international guidelines were also consulted in individual cases when compiling this guideline. In addition, a systematic search and analysis of the literature was carried out using PICO questions where necessary, and other systematic reviews and individual studies were taken into account. For easier comprehension, the assessment tools of the Scottish Intercollegiate Guidelines Network (SIGN) were used to evaluate the quality of additionally consulted studies. Otherwise, the GRADE system was used for the NICE guideline, and the evidence reports of the IQWiG were used to evaluate the quality of the evidence. Recommendations Recommendations and statements were formulated based on identified evidence and/or a structured consensus.

A Systematic Review and Meta-Analysis of Randomized Controlled Trials of Labor Epidural Analgesia Using Moderately High Concentrations of Plain Local Anesthetics versus Low Concentrations of Local Anesthetics with Opioids

Purpose

Compared to low concentrations of local anesthetics with opioids for labor epidural analgesia, very high concentrations of local anesthetics are associated with an increased risk of assisted vaginal delivery. We aimed to investigate if moderately high concentrations of plain local anesthetics are also associated with this risk.

Methods

We searched for published randomized controlled trials that compared moderately high concentrations of plain local anesthetics (>0.1% but ≤0.125% bupivacaine, >0.1% but ≤0.125% levobupivacaine, or >0.17% but ≤0.2% ropivacaine) to low concentrations of local anesthetics (≤0.1% bupivacaine, ≤0.1% levobupivacaine, or ≤0.17% ropivacaine) with opioids for labor analgesia. Meta-analyses were performed to compare the risk of assisted vaginal delivery and other perinatal outcomes between these two groups.

Results

We identified nine randomized controlled trials with a total of 1334 participants. Meta-analysis of these nine trials showed no differences in the risks of assisted vaginal delivery (odds ratio [OR] = 1.18; 95% confidence interval [CI], 0.93–1.49) or Cesarean delivery (OR = 0.96; 95% CI, 0.71–1.29) between the two groups. The incidence of motor block was higher in the group of moderately high concentrations (OR = 4.05; 95% CI, 2.19–7.48), while the incidence of pruritus was lower (OR = 0.07; 95% CI, 0.03–0.16).

Conclusion

This systematic review and meta-analysis suggests that the current evidence is inadequate to support that moderately high concentrations of plain local anesthetics increase the risk of assisted vaginal delivery compared to low concentrations of local anesthetics with opioids.

Comparison of the Effects of Epidural Levobupivacaine with Tramadol or Morphine Addition on Postoperative Analgesia following Major Abdominal Surgery

Objective

The study was designed to compare the postoperative analgesic efficacy of epidural tramadol or epidural morphine as adjuvant to levobupivacaine in major abdominal surgery.

Methods

Patients in ASA I-II group aged between 18 and 65 years were included in study. Epidural catheter was introduced. Patients were randomised into three groups to receive levobupivacaine (Group L), levobupivacaine+morphine (Group LM) and levobupivacaine+tramadol (Group LT). General anaesthesia was administered to all patients. The solution intended for Group L contained 25 mg 0.5% levobupivacaine+15 mL saline, that for Group LM contained 25 mg 0.5% levobupivacaine+14.5 mL salin+100 μg morphine and that for Group LT contained 25 mg 0.5% levobupivacaine+13 mL salin+100 mg tramadol, which was administered via epidural catheter as loading dose 30 min before the end of the operation. Patient-controlled analgesia device was connected to the epidural catheter to provide postoperative analgesia. Bolus dose was adjusted to 12 mg levobupivacaine in Group L, 12 mg levobupivacaine +1.2 mg morphine in Group LM and 12 mg levobupivacaine+12 mg tramadol in Group LT. Lock-out period was adjusted to 15 min in three groups. Quality of analgesia was evaluated using Visual Analogue Scale; administered and demand doses of levobupivacaine, morphine and tramadol were compared at 30 min, 1, 2, 6, 12 and 24 h postoperatively.

Results

Visual Analogue Scale scores were significantly higher in Group L than Groups LM and LT. Nausea and vomiting observed in Group L were lesser than those in Groups LM and LT.

Conclusion

Continuous epidural analgesia using levobupivacaine combined with morphine or tramadol is an effective method for managing postoperative analgesia in major abdominal surgery.

[Recent standards in management of obstetric anesthesia]

The following article contains information not only for the clinical working anaesthesiologist, but also for other specialists involved in obstetric affairs. Besides a synopsis of a German translation of the current "Practice Guidelines for Obstetric Anaesthesia 2016" [1], written by the American Society of Anesthesiologists, the authors provide personal information regarding major topics of obstetric anaesthesia including pre-anaesthesia patient evaluation, equipment and staff at the delivery room, use of general anaesthesia, peridural analgesia, spinal anaesthesia, combined spinal-epidural anaesthesia, single shot spinal anaesthesia, and programmed intermittent epidural bolus.

Practice Guidelines for Obstetric Anesthesia

The American Society of Anesthesiologists Committee on Standards and Practice Parameters and the Task Force on Obstetric Anesthesia and the Society for Obstetric Anesthesia and Perinatology present an updated report of the Practice Guidelines for Obstetric Anesthesia.

Supplemental Digital Content is available in the text.

Quantitative assessment of motor block in labouring women receiving epidural analgesia

The assessment of motor block associated with epidural analgesia is traditionally performed using the modified Bromage Score. However, it is a qualitative and quantitative measurement of both spread and intensity of motor block in the lower limbs, and it has been adapted from Bromage's original use as an assessment of the adequacy of epidural anaesthesia for abdominal surgery. A number of quantitative assessment methods exist but these are either laboratory based and/or impracticable in the clinical situation of labour. We therefore set out to devise a quantitative assessment method which would be easy to use and acceptable to labouring women receiving epidural analgesia. A force transducer was modified to enable power of hip adduction to be assessed quantitatively before and after epidural analgesia was established. These results were compared with the modified Bromage Scale and an extended scale which further subdivided the scores between 0 and 1. Our results show that there is a large variation in the quantitative measurement of motor block (as measured by adductor strength) that may not be detected by the sole use of the modified Bromage Score. We suggest that future studies to assess motor block in the clinical setting use an additional quantitative method of assessment.

Maternal morbidity, mortality, and risk assessment

Maternal deaths in developed countries continue to decline and are rare. Maternal mortality statistics are essentially similar in the United States and United Kingdom. However, the situation is completely different in developing countries, where maternal mortality exceeds 0.5 million every year. This article not only assesses morbidity risks in some of the leading causes of maternal death but also highlights strategies to minimize the risks and to prevent maternal morbidity and mortality.

Local Anesthetics and Mode of Delivery: Bupivacaine Versus Ropivacaine Versus Levobupivacaine

BACKGROUND

The influence of the labor epidural local anesthetic (LA) on mode of delivery has not been adequately studied. In this study, we sought to determine if there is a difference in mode of delivery among parturients who receive epidural bupivacaine, ropivacaine, or levobupivacaine.

METHODS

Nulliparous women at term requesting labor analgesia with a cervical dilation <5 cm were randomized to receive epidural bupivacaine, ropivacaine, or levobupivacaine. Analgesia was initiated with a bolus of 15 mL of 0.0625% of the assigned LA with fentanyl 2 microg/mL. Analgesia was maintained with an infusion of the same solution at 10 mL/h. The primary endpoint was the operative delivery rate (instrumental assisted vaginal delivery plus cesarean delivery).

RESULTS

Ninety-eight women received bupivacaine, 90 ropivacaine, and 34 levobupivacaine (before it was removed from the US market). There was no significant difference in the operative delivery rate (bupivacaine = 46%, ropivacaine = 39%, and levobupivacaine = 32%, P = 0.35) among groups. There was less motor block in the levobupivacaine group when compared with the ropivacaine and bupivacaine groups, P < 0.05. There was no significant difference in the duration of the first or second stage of labor, the total dose of LA received per hour of labor, or neonatal outcome among groups.

CONCLUSIONS

Bupivacaine, ropivacaine, and levobupivacaine all confer adequate labor epidural analgesia, with no significant influence on mode of delivery, duration of labor, or neonatal outcome.

Impact of walking epidural analgesia on obstetric outcome of nulliparous women in spontaneous labour

BACKGROUND

To explore the effects of walking epidural analgesia on obstetric and neonatal outcomes, we performed a case-control study.

METHOD

Each nulliparous woman receiving walking epidural analgesia using 0.0625% bupivacaine (n = 44) was matched to two nulliparous historical controls receiving 0.125% or 0.25% bupivacaine (n = 88 each) for epidural analgesia while recumbent.

RESULTS

Maternal and obstetric parameters, fetal status and presentation, and oxytocin use were comparable among groups. Those receiving walking epidural analgesia walked for a mean of 60 min (range: 20-75 min). In the control groups the mean total durations of labour were shorter (58 min in the 0.125% group and 99 min in the 0.25% group, P < 0.05). Significantly fewer walking epidural analgesia cases than controls required instrumental vaginal delivery (P < 0.05). No other differences in obstetric or fetal outcome were observed and no mother fell or stumbled while walking.

CONCLUSION

Although it was associated with a prolonged first stage of labour, walking epidural analgesia appeared safe for nulliparous women and their babies.

Comparison of maternal and neonatal outcomes with epidural bupivacaine plus fentanyl and ropivacaine plus fentanyl for labor analgesia

BACKGROUND

Several studies have been performed to find a safe method of labor analgesia with minimal side effects and toxicity in mother and fetus. We aimed to compare the efficacy and side effects of epidural bupivacaine plus fentanyl and ropivacaine plus fentanyl at low concentrations.

METHOD

Forty ASA I-II parturients' were included in this prospective, double-blind, trial and randomized to receive either bupivacaine or ropivacaine for labor analgesia. Analgesia was initiated with 8 mL of 0.125% solution plus fentanyl 50 microg and maintained with a continuous infusion of 0.0625% solution with fentanyl 2 microg/mL.

RESULTS

There were no differences in pain scores, total dose of local anesthetics used, sensory or motor blockade, labor duration, mode of delivery, side effects, patient satisfaction, or neonatal outcome between the two local anesthetics at these dosages, but at the end of the second stage and delivery, adequate analgesia quality could not be ensured.

CONCLUSION

We found no major advantage of continuous epidural infusion of ropivacaine 0.0625% plus fentanyl 2 microg/mL over bupivacaine 0.0625% plus fentanyl 2 microg/mL for labor analgesia. We believe that different methods or dosages may be tried in order to improve comfort at the second stage of labor and the delivery.

Impact of first-stage ambulation on mode of delivery among women with epidural analgesia

BACKGROUND

New techniques for administering epidural analgesia allow increased mobility for labouring women with epidurals.

AIM

To determine the effect of ambulation or upright positions in the first stage of labour among women with epidural analgesia on mode of delivery and other maternal and infant outcomes.

METHODS

We undertook a systematic review and meta-analysis of randomised controlled trials (RCT) of ambulation or upright positions versus recumbency in the first stage of labour among women with effective first-stage epidural analgesia in an uncomplicated pregnancy. Trials were identified by searching Medline, Embase and CINAHL databases and the Cochrane Trials Register to March 2004. Trial eligibility and outcomes were prespecified. Group tabular data were obtained for each trial and analysed using meta-analytic techniques.

RESULTS

There were five eligible RCT, with a total of 1161 women. There was no statistically significant difference in the mode of delivery when women with an epidural ambulated in the first stage of labour compared with those who remained recumbent: instrumental delivery (relative risk (RR) = 1.16, 95% confidence interval (CI) 0.93-1.44) and Caesarean section (RR = 0.91, 95% CI 0.70-1.19). There were no significant differences between the groups in use of oxytocin augmentation, the duration of labour, satisfaction with analgesia or Apgar scores. There were no apparent adverse effects of ambulation, but data were reported by only a few trials.

CONCLUSIONS

Although ambulation in the first stage of labour for women with epidural analgesia provided no clear benefit to delivery outcomes or satisfaction with analgesia, neither were there are any obvious harms.

Patient-controlled epidural analgesia for labor pain: effect on labor, delivery and neonatal outcome of 0.125% bupivacaine vs 0.2% ropivacaine

The objective was to evaluate the influence of patient-controlled epidural analgesia (PCEA) using low doses of bupivacaine vs. ropivacaine, on labor pain, motor blockade, progression of labor, delivery and neonatal outcome. This randomized double blind study included 565 parturients. All received a 5-mL/h infusion and PCEA (5-mL boluses with a 20-min lockout, maximum volume 20 mL/h) of either 0.125% bupivacaine (n = 313: 165 nulliparous, 148 parous) or 0.2% ropivacaine (n = 252: 113 nulliparous, 139 parous). Pain score, lower limb motor block, sensory levels, local analgesic doses required, hemodynamic parameters, side effects and complications were assessed. Obstetric variables included cervical dilation at epidural insertion, incidence of ruptured membranes and their duration, use of oxytocin, fetal heart rate changes, duration of labor, mode and outcome of delivery, and use of invasive and non-invasive fetal monitoring. Neonatal characteristics included birth weight, Apgar scores, umbilical artery pH, serum bilirubin, hypoglycemia, need for assisted ventilation, sepsis or sepsis study, feeding difficulties and respiratory distress syndrome. Ropivacaine 0.2% was equianalgesic with 0.125% bupivacaine, but produced less motor block (P < 0.0001). There were no significant differences, however, in duration of labor, delivery type or neonatal outcome.

Ambulatory labor analgesia: what does an obstetrician need to know?

A simple statement that describes the degree of the patient's satisfaction with the pain relief from her labor epidural analgesia has often assessed the quality of labor analgesia as perceived by the patient. Many laboring parturients, midwives, obstetricians and anesthesiologists are increasingly concerned by the limitations of traditional epidural labor analgesia. In general, women dislike the inability to void, the often-dense motor block, the feeling of numbness of the lower body, the total lack of the urge to bear down, and the complete perineal anesthesia. Continuous search for balanced labor analgesia that provides relief from pain, while preserving motor function, has led to the development of an ambulatory labor analgesia technique. This article assesses the validity of various strongly advocated opinions as to whether parturients benefit from ambulation in labor and also reviews the current trends in ambulatory labor analgesia.

Impact study of the introduction of low-dose epidural (bupivacaine 0.1%/fentanyl 2μg.mL−1) compared with bupivacaine 0.25% for labour analgesia

We conducted a retrospective analysis of the obstetric effects of introducing a low-dose epidural regimen for epidural analgesia in labour. Before this, all women in our unit requesting epidural analgesia for labour received intermittent boluses (10 mL) of 0.25% bupivacaine. After the introduction of the low-dose service in March 2000, intermittent boluses (10 mL) of 0.1% bupivacaine with fentanyl 2 microg . mL(-1) were given. The records of 300 women were examined, 150 who had received the standard regimen before the introduction of the new service and 150 women afterwards. The groups were compared for outcome of labour, quality of analgesia and any adverse events related to the epidural analgesia. There was a significant reduction in the low-dose group in the number of women requiring instrumental delivery (41% vs. 29%, P = 0.04). The need for indwelling bladder catheters was also reduced in the patients receiving the low-dose regimen (21.3% vs. 4.7%, P < 0.001). Duration of analgesia was longer in patients receiving bupivacaine 0.25% (mean minimum time between boluses 42.25 +/- 33.8 vs. 24.37 +/- 19.8 min, P < 0.001). The need for further anaesthetic intervention was higher with the low-dose regimen (24% vs. 34%, P = 0.037). Maternal satisfaction was high in both groups (95 and 97%, respectively). We conclude that the introduction of a low-dose regimen of epidural analgesia for labour reduces the incidence of instrumental deliveries. It also decreases the incidence of bladder catheterisation during labour, but the need for anaesthetic intervention may be greater.

Comparison of continuous infusion versus midwife administered top-ups of epidural bupivacaine for labour analgesia: effect on second stage of labour and mode of delivery

Using a population-based study we retrospectively compared the effect of continuous versus intermittent top-up epidural analgesia on the outcome of labour at the University Hospital of Wales. We analysed the labour outcome of 410 primigravid deliveries over an 18-month period during a change in delivery suite protocol. Data were retrieved from the Cardiff Births Survey and the sample was analysed in two groups: group 1 (n = 201) received a continuous infusion of 0.1% bupivacaine plus fentanyl 2 microg/mL and group 2 (n = 209) received intermittent top-ups of the same solution. Outcome measures were the number of operative deliveries and the proportion of those deliveries that were due to prolongation of the second stage of labour. There were no significant differences in terms of group characteristics, women undergoing assisted vaginal delivery (group 1: 83 vs. group 2: 70, OR 0.8 CI 0.5-1.2), caesarean section (group 1: 59 vs. group 2: 61, OR 1.0 CI 0.6-1.5), and women with prolonged second stage (group 1: 50 vs. group 2: 47, OR 1.1 CI 0.6-1.8). The presumed reduction in motor blockade associated with intermittent top-up epidural regimes did not affect the outcome of labour.

Ropivacaine 1 mg/ml, plus fentanyl 2 microg/ml for epidural analgesia during labour. Is mode of administration important?

BACKGROUND

Patient-controlled epidural analgesia (PCEA) with a moderate to high concentration of bupivacaine in obstetrics has been shown to give comparable analgesia and even higher level of satisfaction compared to continuous epidural infusion. We hypothesised that the use of a very low concentration technique (ropivacaine/fentanyl) might result in excessive dosing in the PCEA group, more motor blockade and a negative impact on spontaneous delivery rate.

METHODS

We conducted a randomised, double-blind study of 60 nulliparous women at term comparing low concentration ropivacaine/fentanyl administered in either patient-controlled or fixed continuous infusion mode. Parturients with known predictors of painful deliveries, i.e. breech presentation, primary induction of labour, were not included. Deliveries within 90 min from the start of epidural analgesia were omitted from the evaluation.

RESULTS

We found that both groups required a mean of 12 ml/h low concentration mixture (loading and midwife rescue boluses included). There was no difference between groups with respect to spontaneous delivery rate (71%). This low concentration technique resulted in haemodynamic stability without crystalloid preloading, infusion or vasopressor use. Motor blockade of clinical importance was not detected in any patient.

CONCLUSION

We conclude that epidural use of ropivacaine 1 mg/ml+fentanyl 2 microg/ml provides effective analgesia with equal volume requirements irrespective of administration mode, with a high spontaneous delivery rate. Choice of PCEA or CEI (continuous epidural infusion) should be directed by other considerations, most importantly compliance of midwife and possible reduction in workload for anaesthesiology staff.

A comparison of 0.0625% bupivacaine with fentanyl and 0.1% ropivacaine with fentanyl for continuous epidural labor analgesia

We compared the analgesic efficacy and the degree of motor block achieved with epidural infusion of 0.0625% bupivacaine (Group B) versus 0.1% ropivacaine (Group R), both with 0.0002% fentanyl (2 microg/mL) in laboring patients. A prospective, double-blinded study was performed in 98 ASA physical status I-II parturients who were divided randomly into two groups to receive either bupivacaine or ropivacaine after catheter location had been tested with an initial bolus of lidocaine and fentanyl. The infusion rate was 15 mL/h in every case. When pain was perceived, 5-mL boluses of the assigned epidural analgesic were administered every 10 min until analgesia was achieved. We recorded pain intensity, level of sensory block, degree of motor block, hemodynamic variables, secondary effects, mode of delivery, neonatal outcome, and patient satisfaction. There were no statistically significant differences in any of the factors analyzed. Highly effective analgesia was achieved in both groups with a small incidence of motor block. These findings suggest that bupivacaine may be more potent than ropivacaine.

IMPLICATIONS

We compared different concentrations of epidural bupivacaine and ropivacaine thought to be equipotent. Both solutions were equally efficient in providing highly effective epidural analgesia for labor with minimal motor block. These findings suggest that bupivacaine may be more potent than ropivacaine.

Comparison of fentanyl and sufentanil in combination with bupivacaine for patient-controlled epidural analgesia during labor

STUDY OBJECTIVES

To compare the efficacy of fentanyl plus bupivacaine with sufentanil plus bupivacaine for treatment of pain during labor and delivery using patient-controlled epidural analgesia (PCEA).

DESIGN

Prospective, double-blind, clinical investigation.

SETTINGS

University-affiliated hospital.

PATIENTS

226 ASA physical status I and II laboring patients.

INTERVENTIONS

Patients were randomized to receive 0.125% bupivacaine with fentanyl (2 micro g.ml(-1)) or 0.125% bupivacaine with sufentanil (0.25 micro g.ml(-1)) through PCEA.

MEASUREMENTS

Maternal analgesia assessed by visual analog scale was recorded before epidural block, 1 and 3 hours after epidural block, at full cervical dilation, and at delivery. Motor blockade assessed by Bromage scale was recorded at delivery.

MAIN RESULTS

Nine patients in group fentanyl, and 11 in group sufentanil were excluded from the study. Overall analgesia was good and no difference was observed between the two groups. Total boluses of 4 mL bupivacaine-opioid administered and the number of supplementary top-up injections of 5 mL 0.25% bupivacaine were similar in both groups. In group sufentanil, motor blockade and pruritus were significantly lower than in group fentanyl. Nausea was not recorded in any patients. Mode of delivery was similar in both groups, i.e., cesarean section, vacuum or forceps, or spontaneous vaginal delivery. No difference was observed in Apgar scores.

CONCLUSIONS

Sufentanil is preferable to fentanyl during bupivacaine PCEA as there is less incidence of motor blockade and pruritus.

Ropivacaine 0.2% versus bupivacaine 0.1% with fentanyl: a double blind comparison for analgesia during labour

We have performed a randomized, double-blind comparison of two epidural drug regimens for analgesia in labour. In the bupivacaine group (BUPIV), 101 healthy parturients received 0.1% bupivacaine with fentanyl 2 microg ml(-1). In the ropivacaine group (ROPIV), 102 women received 0.2% ropivacaine. Both groups received an initial loading dose of 15 ml, a continuous infusion of 8 ml h(-1), and top-ups of 10 ml. Breakthrough pain not responding to a routine top-up was treated with an 'escape' top-up of 10 ml 0.25% bupivacaine. The two groups were compared for complete analgesia at 30 min, routine and 'escape' top-up requirements, midwife assessment of analgesic efficacy, delivery mode, patient visual analogue scores (VAS) for first and second stage analgesia, overall satisfaction, and patient assessment of motor blockade. Patients receiving ropivacaine received fewer routine top-ups (median 1.0 vs. 2.0, P=0.001) and fewer escape top-ups (9.8% vs. 21.8%, P=0.02). The ropivacaine group was more likely to be pain free in the first stage (51% vs. 33.7%, P=0.01). There were no significant differences in patients' assessment of motor block or mode of delivery between the groups. Pain relief and satisfaction scores from midwives and patients were consistently better in the ropivacaine group, but did not reach statistical significance.

A survey of epidural analgesia for labour in the United Kingdom

A postal survey of obstetric units throughout the UK was conducted to obtain information about the provision of epidural analgesia for labour. Ninety per cent of units offered a 24-h epidural service and the average epidural rate was 24%. The most commonly administered epidural test dose was 3 ml of bupivacaine 0.5% and bupivacaine 0. 25% was most often used as the initial epidural top-up. Continuous infusions of low-dose bupivacaine and opioid mixtures were the most popular method of maintenance epidural analgesia. Twenty-four per cent of units offered combined spinal-epidural analgesia in addition to standard epidural analgesia. Midwives played a prominent role in the administration of epidural bolus top-ups and also in the assessment and maintenance of continuous epidural infusions.

Epidural analgesia in association with duration of labor and mode of delivery: a quantitative review

OBJECTIVE

This study was undertaken to quantitatively summarize previous literature on the effects of epidural analgesia in labor on the duration of labor and mode of delivery.

STUDY DESIGN

Original studies published in English from 1965 through December 1997 were reviewed and assigned a quality score independently by 2 of the authors. Studies that met the minimal requirements were evaluated further. Data syntheses were performed separately according to study design and outcome measurements, including cesarean delivery, instrumental delivery, oxytocin augmentation, and durations of the first and second stages of labor.

RESULTS

Seven randomized clinical trials and 5 observational studies met the minimal requirements. Among them 4 studies of each sort were included in the data synthesis. Both types of studies showed that epidural analgesia increased risk of oxytocin augmentation 2-fold. Clinical trials suggested that epidural analgesia did not increase the risk of cesarean delivery either overall or for dystocia, nor did it significantly increase the risk of instrumental vaginal delivery; however, observational studies reported a more than 4-fold increased risk of cesarean and instrumental deliveries. Although most studies showed a longer labor among women with epidural analgesia than without it, especially during the second stage, most of the studies used inappropriate statistical analysis.

CONCLUSION

Epidural analgesia with low-dose bupivacaine may increase the risk of oxytocin augmentation but not that of cesarean delivery.

Maternal satisfaction with labour analgesia

Satisfaction with childbirth is a multidimensional issue, of which analgesia is but one component. The importance of analgesia as a contribution to overall satisfaction has been recognized increasingly in the last 50 years, but improvement in quality of available analgesia has not always resulted in commensurate improvement in satisfaction. Satisfaction by its very nature has proved to be difficult both to define and to quantify, and no reliable standards of measurement have been accepted. Pain relief in childbirth is subject to many social and cultural modifiers, which continue to change. Control of pain rather than absolute amelioration is seen by many to provide greater satisfaction. Analgesia issues still do not figure prominently in the overall satisfaction of the birthing process for the vast majority of women, despite the availability of and demand for improved methods of relief. The interpersonal relationships established between patient and healthcare providers may ultimately be of more importance in the determination of satisfaction with management.

Neuraxial opioids in labour

Neuraxial opioids were first used for labour analgesia in 1980 following the description of spinal cord opioid receptors in 1979. Via these receptors in the dorsal horn, opioids modulate both the visceral and the somatic pain of labour. The onset and duration of action of the individual opioid are determined primarily by its relative lipid solubility. Neuraxial opioids have a local anaesthetic sparing effect, allowing the use of lower concentrations of both agents while maintaining analgesia. As a sole agent, intrathecal opioids can be used to provide analgesia during the first stage of labour, especially in the high-risk parturient. They also have a role in the management of perineal pain and the provision of rapid-onset analgesia. Unfortunately maternal and neonatal side-effects can occur, the most important being respiratory depression.

The effects of epidural analgesia on the course and outcome of labour

The potential effects of epidural analgesia on the progress and outcome of labour have been the subject of lasting controversy. Retrospective reviews indicate that epidurals are associated with longer labours and/or an increase in the incidence of instrumental or operative delivery. Similar results were obtained in non-randomized prospective studies. None of them established a causal relationship, because without randomization the selection bias cannot be ruled out. Other factors, such as premature rupture of membranes and maternal socioeconomic status, may affect the outcome of labour. It was also reported that introduction of the on-demand epidural service did not increase the primary caesarean section rate. The few prospective randomized studies are contradictory and not very reliable owing to small patient populations and high cross-over rates. There is, however, unanimity among the authors regarding the superiority of pain relief provided by epidural blocks over systemically administered opioids.

The effects of pain and its management on mother and fetus

Childbirth is frequently accompanied by pain. For religious, cultural and philosophical reasons many groups have sought to prevent treatment of pain. Pain may have adverse effects on the mother and fetus. The psychological effects of severe pain should not be overlooked particularly where it is associated with an adverse fetal or maternal outcome. There are a number of different forms of pain relief in labour with differing side-effects and efficacies. The controversy concerning medical management of women in labour has been used to dissuade women from requesting pain relief. This debate has encouraged the use of a patient-centred philosophy of care that encourages the patient to retain control. However, good pain relief may allow the women to retain control if administered in a sensitive manner. The ideal analgesic in labour is discussed. Recent and future developments of analgesia in childbirth are discussed with respect to this.

Comparison of three different loading doses to establish epidural analgesia in labour

Women requesting epidural analgesia were randomized to receive one of three loading doses. Group 1 received a single dose of bupivacaine 9.375 mg (15 ml of 0.0625%) containing fentanyl 37.5 microg and adrenaline 37.5 microg group 2 received a single dose of bupivacaine 15 mg (15 ml of 0.1%) containing fentanyl 30 microg and adrenaline 30 microg and group 3 received a test dose of bupivacaine 10 mg (4 ml of 0.25% - test) followed 5 min later by bupivacaine 20 mg (8 ml of 0.25% - loading). All groups received an infusion of bupivacaine 0.0625% with fentanyl 0.00025% and adrenaline 0.00025% at 10-12 ml/h started 15 min after the loading dose. Speed of onset of analgesia was the same in all three groups, with the majority of women achieving satisfactory analgesia by 20 min. Motor block was significantly increased in group 3 at 30 min, but by 1 h there was no difference in motor block between the groups.

Dorsal column function after epidural and spinal blockade: implications for the safety of walking following low-dose regional analgesia for labour

Walking after regional blockade for labour using low-dose combinations of bupivacaine and fentanyl is possible due to the maintenance of lower limb motor power. In order to investigate concerns that dorsal column function, important in maintaining balance, is impaired after such techniques, clinical assessment of lower limb proprioception and vibration sense was evaluated in parturients after either low-dose epidural (n = 30) or spinal blockade (n = 30) for labour analgesia and compared with spinal anaesthesia (n = 30) for elective Caesarean section using a larger total dose of local anaesthetic. Of the patients receiving low-dose regional labour analgesia 7% (n = 4) had abnormal dorsal column function compared with 97% (n = 29) receiving spinal anaesthesia for Caesarean section (p < 0.001). All patients in the Caesarean section group developed lower limb motor weakness, compared with only 10% (n = 6) in the low-dose groups (p < 0.001). There were no significant differences between the low-dose groups with respect to sensory block, motor block or dorsal column function. Overall, 90% of patients receiving low-dose bupivacaine/fentanyl regional labour analgesia had both normal lower limb motor power and dorsal column function. Assessment of these parameters is recommended before allowing patients to walk after low-dose regional techniques for labour.

Long term backache after childbirth: prospective search for causative factors

OBJECTIVES

To assess in a prospective randomised study the association between motor block resulting from high and low dose epidural infusions of bupivacaine in labour and the incidence of long term backache after childbirth, and to compare the incidence of backache in women not receiving epidural analgesia.

DESIGN

Women requesting epidural analgesia in labour between October 1991 and March 1994 were randomised to receive infusions of either bupivacaine alone or low dose bupivacaine with opioid. Data were collected during labour and the immediate postpartum period from these women and from women recruited at random over the same time from those who had laboured without epidural analgesia. A postal questionnaire about symptoms was sent three months after childbirth to all women. Further data were collected one year after childbirth from those who had reported new backache at three months.

SETTING

St Thomas's Hospital, London.

SUBJECTS

599 women were recruited, of whom 450 (75%) replied to a follow up questionnaire.

RESULTS

152 women (33.8% of responders) reported backache lasting three months after delivery and, of these, 33 (7.3%) had not previously suffered with backache. There were no significant differences between the treatment groups in the incidence of postnatal backache overall or of new backache or any symptoms after childbirth. Among all demographic, obstetric, and epidural variables examined the only factors significantly associated with backache after childbirth were backache before and during pregnancy.

CONCLUSIONS

The incidence of new long term backache was not significantly increased in women who received epidural analgesia in labour. Motor block resulting from epidural local anaesthetic administration was not a significant factor in the development of backache.