Patient-Controlled Epidural Analgesia for Labor

Prospective longitudinal cohort questionnaire assessment of labouring women's preference both pre- and post-delivery for either reduced pain intensity for a longer duration or greater pain intensity for a shorter duration

BACKGROUND

Assessments of labour pain focus on pain intensity, not on duration. We aimed to assess the importance labouring women apply to pain intensity and duration before labour and post-delivery.

METHODS

Forty healthy women scheduled for labour induction were enrolled in this institutional review board-approved, prospective cohort study. Participants completed a pain preference questionnaire before active labour and within 24-h of delivery. The questionnaire consisted of seven stem questions that evaluated preference for pain intensity or duration. The pain preference ratio was determined by dividing the percentage of women who preferred reduced pain intensity for longer duration by that of those who preferred greater pain intensity for shorter duration (estimate of the odds). The overall hypothetical pain burden was determined by multiplying intensity by time. All questions presented the same overall hypothetical pain burden.

RESULTS

Pain preference questionnaire scores demonstrated preference for low intensity pain for a longer duration rather than higher intensity for a shorter duration, both pre-labour (P<0.001) and post-delivery (P<0.001): the null median imputed as 3 of 6 (i.e. no preference for pain intensity over pain duration). This preference for pain duration over intensity was greater post-delivery compared with before labour (P=0.03). There was a significant correlation (r=0.83; P=0.04) between the pain preference ratio vs overall hypothetical pain burden before labour but not after delivery (r=0.28; P=0.59).

CONCLUSIONS

In this preliminary labour assessment, women preferred lower pain intensity at the cost of longer pain duration. This suggests that pain intensity is the primary driver of hypothetical pain burden-a preference reinforced post-delivery.

Patient-controlled epidural levobupivacaine with or without fentanyl for post-cesarean section pain relief

PURPOSE

The purpose of this study was to compare the analgesic properties of levobupivacaine with or without fentanyl for patient-controlled epidural analgesia after Cesarean section in a randomized, double-blinded study.

METHODS

We enrolled American Society of Anesthesiologists class I/II, full-term pregnant women at National Taiwan University Hospital who received patient-controlled epidural analgesia after Cesarean section between 2009 and 2010. Eighty women were randomly assigned into two groups. In group A, the 40 subjects received drug solutions made of 0.6 mg/ml levobupivacaine plus 2 mcg/ml fentanyl, and in group B the 40 subjects received 1 mg/ml levobupivacaine. Maintenance was self-administered boluses and a continuous background infusion.

RESULTS

There were no significant differences in the resting and dynamic pain scales and total volume of drug used between the two groups. Patient satisfaction was good in both groups.

CONCLUSION

Our study showed that pure epidural levobupivacaine can provide comparative analgesic properties to the levobupivacaine-fentanyl combination after Cesarean section. Pure levobupivacaine may serve as an alternative pain control regimen to avoid opioid-related adverse events in parturients.

The role of maternal attachment in the experience of labor pain: a prospective study

OBJECTIVE

To examine the influence of attachment dimensions and sociodemographic and physical predictors in the experience of labor pain.

METHODS

Eighty-one pregnant women were assessed during their third trimester of pregnancy and during labor. The perceived intensity of pain in the early stages of labor (3 cm of cervical dilatation) and before the administration of patient-controlled epidural analgesia was measured using a visual analog scale. Pain was also assessed indirectly based on anesthetic doses. Attachment was assessed using the Adult Attachment Scale-Revised.

RESULTS

Attachment anxiety and avoidance were positively and significantly correlated with labor pain and anesthetic consumption. In the multivariate models, attachment anxiety was a significant predictor of higher pain at 3 cm of cervical dilatation (β = 0.36, p = .042) and before the administration of patient-controlled epidural analgesia (β = 0.51, p = .002). Older age (β = 0.31, p = .005), a shorter duration of labor (β= -0.41, p = .001), and attachment avoidance (β = 0.41, p = .004) were significant predictors of higher anesthetic use.

CONCLUSIONS

The study findings suggest that perceived labor pain and anesthetic use are strongly associated with attachment, rather than demographic and physical factors. These data support the importance of understanding the experience of labor pain within an attachment theoretical framework.

Attachment styles, pain, and the consumption of analgesics during labor: a prospective observational study

Individuals with less secure attachment styles have been shown to experience more pain than people with more secure attachment styles; however, attachment styles have not yet been examined in the context of labor pain and analgesic consumption. The purpose of this prospective observational study was to assess the influence of the mother's attachment style on the perception of labor pain, as assessed by a visual analog scale and analgesic consumption. Eighty-one pregnant women with a mean age of 32 years (standard deviation = 5.1) were assessed during the third trimester of pregnancy and during labor. The physical predictors of labor pain were recorded, and the adult attachment style was assessed with the Adult Attachment Scale-Revised. For labor analgesia, a low dose of patient-controlled epidural analgesia protocol (ropivacaine .6 mg/mL plus sufentanil .5 μg/mL) was used. Women with a secure attachment style reported significantly less labor pain (P < .001) and a significantly lower analgesic consumption during labor (P < .001) than insecurely attached women. These findings suggest that women's attachment style was associated with labor pain and analgesic consumption and support the relevance of the attachment theory as a promising conceptual framework for understanding labor pain.

PERSPECTIVE

This study showed that women with an insecure attachment style were more likely to report higher pain before patient-controlled epidural analgesia and higher analgesic consumption and to request supplemental analgesia during labor. The assessment of adult attachment has the potential to identify women at high risk of poorly coping with pain during childbirth.

Analgesia for childbirth: modern insights into an age-old challenge and the quest for an ideal approach

SUMMARY It is widely recognized that childbirth may be the most painful experience in a woman’s lifetime and that women have a right to relief. There are many options, but the efficacy of only a few is supported by robust evidence. Many influences determine which method of pain relief is chosen, including social and cultural factors, availability, cost and personal preference. Due to human diversity and the differing perspectives of consumers, obstetric care providers and health administrators, there is no such thing as ‘an ideal approach’. In resource-rich societies, major advances in parturient safety and outcome flow from technique development and better monitoring. Greater awareness of the negative impact of untreated pain and of the relevance of genetic, cultural and social factors motivates research into better predictive models, novel therapies and optimization of existing methods.

Some epidurographic explanations for incomplete epidural analgesia coverage in the absence of a catheter

STUDY OBJECTIVE

To determine the impact of the plica mediana dorsalis (PMD) on injected contrast media spread in the epidural space.

DESIGN

Prospective interventional study.

SETTING

Academic medical center.

PATIENTS

30 chronic pain patients ranging in age from 37 to 71 years, undergoing epidural steroid injection.

INTERVENTIONS AND MEASUREMENTS

Epidurograms were evaluated for the 1) presence or absence of a PMD and 2) bilateral differential density and the extent of contrast spread on either side of the midline, horizontally and vertically.

RESULTS

The PMD (defined as midline radiolucency in epidurograms) was observed in (80%) 24/30 patients based on the epidurograms that were evaluated. Denser contrast spread on one side was found in (79%) 19/24 patients who had the PMD and in (33%) 2/6 patients who did not have the PMD (P = 0.03). Horizontal and vertical asymmetrical spread of the contrast was observed in (67%) 16 of 24 patients with the PMD and in (50%) 3 of 6 of patients without the PMD in each direction independently.

CONCLUSION

The difference in density of contrast spread on either side of the midline carries important clinical implications in understanding the pathogenesis of inadequate epidural analgesia and/or unilateral excessive motor weakness or numbness.

[New aspects of obstetric anesthesia]

BACKGROUND

The risk profile of patients in obstetric anesthesia has substantially changed. Even more so than other disciplines, obstetric anesthesia is therefore in the true sense of the word dependent on the close coordination of all concerned and a good interdisciplinary cooperation.

AIM

This article explains the important anesthesiological risks connected with parturition and presents the corresponding concepts for prevention, diagnosis and management of peripartum complications.

MATERIAL AND METHODS

The increase in the number of high risk pregnancies, which are mostly due to an increase in obesity, require clearly defined guidelines and interdisciplinary concepts which are described and discussed in this article. The neuraxial block is still the most effective procedure for treatment of birth pain and offers a promising new method with the programmed intermittent epidural boluses presented in this article. Finally, the German speaking countries Germany, Austria and Switzerland have developed a treatment algorithm for the management of postpartum hemorrhage which is presented here.

RESULTS

The anesthesiological components of a risk pregnancy must be recognized early and include obesity, preeclampsia and drug-induced coagulopathy. Epidural analgesia is the most effective analgesic procedure in obstetrics. Patient-controlled remifentanil analgesia currently represents the best alternative in cases of contraindications for a neuraxial procedure.

CONCLUSION

In risk situations, such as pre(eclempsia), emergency cesarean section, massive blood loss or other peripartum emergency situations, optimal interdisciplinary cooperation between midwives, obstetricians and anesthetists is required. However, not only emergency situations require a good interdisciplinary cooperation. Just as important is the cooperation to recognize risk pregnancies and a timely joint planning of the approaching birth.

Pregnancy outcome using general anesthesia versus spinal anesthesia for in vitro fertilization

Background

There is a considerable rate of fertility failure and this causes a great burden of untoward effects for patients. Usually a considerable number of these patients undergo anesthesia for their treatment.

Objectives

This study was designed to compare the effects of general and spinal anesthesia on these patients.

Patients and Methods

In a randomized clinical trial, after taking informed written consent from the patients, 200 patients entered the study; 100 in each. During a 2 year period, women aged 20 to 40 years entered the study (one group receiving spinal anesthesia and the other, receiving general anesthesia). Ovum retrieval protocols were the same. Nonparametric and parametric analyses were used for data analysis. P value less than 0.05 was considered significant.

Results

There was no difference between the two groups regarding demographic variables. 15 of 100 patients (15%) in the general anesthesia group and 27 of 100 patients (27%) in the spinal anesthesia group had successful pregnancy after IVF; so, spinal anesthesia increased significantly the chance of IVF success (P value < 0.001; Chi Square).

Conclusions

The results of this study demonstrated that spinal anesthesia increased the chance of fertilization success.

Effect of ritonavir-induced cytochrome P450 3A4 inhibition on plasma fentanyl concentrations during patient-controlled epidural labor analgesia: a pharmacokinetic simulation

BACKGROUND

Ritonavir inhibition of cytochrome P450 3A4 decreases the elimination clearance of fentanyl by 67%. We used a pharmacokinetic model developed from published data to simulate the effect of sample patient-controlled epidural labor analgesic regimens on plasma fentanyl concentrations in the absence and presence of ritonavir-induced cytochrome P450 3A4 inhibition.

METHODS

Fentanyl absorption from the epidural space was modeled using tanks-in-series delay elements. Systemic fentanyl disposition was described using a three-compartment pharmacokinetic model. Parameters for epidural drug absorption were estimated by fitting the model to reported plasma fentanyl concentrations measured after epidural administration. The validity of the model was assessed by comparing predicted plasma concentrations after epidural administration to published data. The effect of ritonavir was modeled as a 67% decrease in fentanyl elimination clearance. Plasma fentanyl concentrations were simulated for six sample patient-controlled epidural labor analgesic regimens over 24 h using ritonavir and control models. Simulated data were analyzed to determine if plasma fentanyl concentrations producing a 50% decrease in minute ventilation (6.1 ng/mL) were achieved.

RESULTS

Simulated plasma fentanyl concentrations in the ritonavir group were higher than those in the control group for all sample labor analgesic regimens. Maximum plasma fentanyl concentrations were 1.8 ng/mL and 3.4 ng/mL for the normal and ritonavir simulations, respectively, and did not reach concentrations associated with 50% decrease in minute ventilation.

CONCLUSION

Our model predicts that even with maximal clinical dosing regimens of epidural fentanyl over 24 h, ritonavir-induced cytochrome P450 3A4 inhibition is unlikely to produce plasma fentanyl concentrations associated with a decrease in minute ventilation.

A Clinical Evaluation of the GemStar® and the AmbIT® Pumps for Patient-Controlled Epidural Analgesia

Background

Patient-controlled analgesia is used for both labor and postoperative analgesia.

Objectives

This study aimed to assess user satisfaction and functionality of two ambulatory, electronic patient controlled analgesia devices, the GemStar pump Hospira Inc., Illinois, USA) and the ambIT Ambulatory Infusion Therapy pump (Sorenson Medical Products, Utah, USA).

Patients and Methods

It was a randomized clinical trial of laboring women and postoperative gynecology patients receiving patient-controlled epidural analgesia. Patients were randomized to use one of the pumps and both anesthesiologists and patients completed questionnaires about aspects of pump function, and rated their satisfaction with the equipment. Midwives and high-dependency unit nurses also evaluated the pumps in each clinical setting.

Results

Forty patients, 20 laboring women and 20 postoperative patients were randomized and completed the study. The pumps were compared by nine anesthesiologists. Patient and staff satisfaction with both devices was high. Patient satisfaction did not significantly differ between groups (median 10 [8, 10] for the GemStar and 10 [9, 10] for the ambIT, P = 0.525]. The median staff satisfaction score was 8 [6, 8] for the GemStar and 7 [5, 8] for the ambIT (P = 0.154). Both patient cohorts rated each pump highly for most aspects of clinical function. Staff rated the ambIT pump more favourably with respect to portability and storage at the bedside whilst the GemStar had better assessments with respect to its consumables and interactions involving the electronic interface.

Conclusions

Both devices were well-rated by patients and staff, with no significant difference between them for overall satisfaction, and only minor differences with respect to their respective strengths and weaknesses.

Pain management for women in labour: an overview of systematic reviews

BACKGROUND

The pain that women experience during labour is affected by multiple physiological and psychosocial factors and its intensity can vary greatly.  Most women in labour require pain relief. Pain management strategies include non-pharmacological interventions (that aim to help women cope with pain in labour) and pharmacological interventions (that aim to relieve the pain of labour).

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on the efficacy and safety of non-pharmacological and pharmacological interventions to manage pain in labour. We considered findings from non-Cochrane systematic reviews if there was no relevant Cochrane review.

METHODS

We searched the Cochrane Database of Systematic Reviews (The Cochrane Library 2011, Issue 5), The Cochrane Database of Abstracts of Reviews of Effects (The Cochrane Library 2011, Issue 2 of 4), MEDLINE (1966 to 31 May 2011) and EMBASE (1974 to 31 May 2011) to identify all relevant systematic reviews of randomised controlled trials of pain management in labour. Each of the contributing Cochrane reviews (nine new, six updated) followed a generic protocol with 13 common primary efficacy and safety outcomes. Each Cochrane review included comparisons with placebo, standard care or with a different intervention according to a predefined hierarchy of interventions. Two review authors extracted data and assessed methodological quality, and data were checked by a third author. This overview is a narrative summary of the results obtained from individual reviews.

MAIN RESULTS

We identified 15 Cochrane reviews (255 included trials) and three non-Cochrane reviews (55 included trials) for inclusion within this overview. For all interventions, with available data, results are presented as comparisons of: 1. Intervention versus placebo or standard care; 2. Different forms of the same intervention (e.g. one opioid versus another opioid); 3. One type of intervention versus a different type of intervention (e.g. TENS versus opioid). Not all reviews included results for all comparisons. Most reviews compared the intervention with placebo or standard care, but with the exception of opioids and epidural analgesia, there were few direct comparisons between different forms of the same intervention, and even fewer comparisons between different interventions. Based on these three comparisons, we have categorised interventions into: " What works" ,"What may work", and "Insufficient evidence to make a judgement".WHAT WORKSEvidence suggests that epidural, combined spinal epidural (CSE) and inhaled analgesia effectively manage pain in labour, but may give rise to adverse effects. Epidural, and inhaled analgesia effectively relieve pain when compared with placebo or a different type of intervention (epidural versus opioids). Combined-spinal epidurals relieve pain more quickly than traditional or low dose epidurals. Women receiving inhaled analgesia were more likely to experience vomiting, nausea and dizziness.When compared with placebo or opioids, women receiving epidural analgesia had more instrumental vaginal births and caesarean sections for fetal distress, although there was no difference in the rates of caesarean section overall. Women receiving epidural analgesia were more likely to experience hypotension, motor blockade, fever or urinary retention. Less urinary retention was observed in women receiving CSE than in women receiving traditional epidurals. More women receiving CSE than low-dose epidural experienced pruritus.  WHAT MAY WORKThere is some evidence to suggest that immersion in water, relaxation, acupuncture, massage and local anaesthetic nerve blocks or non-opioid drugs may improve management of labour pain, with few adverse effects.  Evidence was mainly limited to single trials. These interventions relieved pain and improved satisfaction with pain relief (immersion, relaxation, acupuncture, local anaesthetic nerve blocks, non-opioids) and childbirth experience (immersion, relaxation, non-opioids) when compared with placebo or standard care. Relaxation was associated with fewer assisted vaginal births and acupuncture was associated with fewer assisted vaginal births and caesarean sections.INSUFFICIENT EVIDENCEThere is insufficient evidence to make judgements on whether or not hypnosis, biofeedback, sterile water injection, aromatherapy, TENS, or parenteral opioids are more effective than placebo or other interventions for pain management in labour. In comparison with other opioids more women receiving pethidine experienced adverse effects including drowsiness and nausea. 

AUTHORS' CONCLUSIONS

Most methods of non-pharmacological pain management are non-invasive and appear to be safe for mother and baby, however, their efficacy is unclear, due to limited high quality evidence. In many reviews, only one or two trials provided outcome data for analysis and the overall methodological quality of the trials was low. High quality trials are needed.There is more evidence to support the efficacy of pharmacological methods, but these have more adverse effects. Thus, epidural analgesia provides effective pain relief but at the cost of increased instrumental vaginal birth.It remains important to tailor methods used to each woman's wishes, needs and circumstances, such as anticipated duration of labour, the infant's condition, and any augmentation or induction of labour.A major challenge in compiling this overview, and the individual systematic reviews on which it is based, has been the variation in use of different process and outcome measures in different trials, particularly assessment of pain and its relief, and effects on the neonate after birth. This made it difficult to pool results from otherwise similar studies, and to derive conclusions from the totality of evidence. Other important outcomes have simply not been assessed in trials; thus, despite concerns for 30 years or more about the effects of maternal opioid administration during labour on subsequent neonatal behaviour and its influence on breastfeeding, only two out of 57 trials of opioids reported breastfeeding as an outcome. We therefore strongly recommend that the outcome measures, agreed through wide consultation for this project, are used in all future trials of methods of pain management.

Effects of predistention with normal saline containing adrenaline on blood-vessel injury during epidural catheter placement

This study investigated the effects of predistention with normal saline containing adrenaline on vascular plexus injury during epidural catheter placement. Three hundred parturients undergoing caesarean sections were randomly divided into three groups. Group I (n = 102) received an epidural injection with 5 ml normal saline; group II (n = 93) received 5 ml normal saline containing adrenaline (5 μg/ml); group III (n = 100) received direct epidural catheter placement. Five women were excluded from the analysis for technical reasons. The incidence of bloody fluid in the epidural needle was significantly lower in groups I and II compared with group III (eight [7.8%] and seven [7.5%] versus 17 [17.0%], respectively). There were no significant differences in the incidence of bloody fluid in the epidural catheter or in the incidence of intravascular epidural catheter placement between the three groups. Predistention with 5 ml normal saline before catheter insertion reduced the incidence of blood-vessel injury during epidural catheter placement, but adrenaline provided no additional protective effects.

Onset of labor epidural analgesia with ropivacaine and a varying dose of fentanyl: a randomized controlled trial

BACKGROUND

This study was conducted to investigate the onset of labor epidural analgesia using 0.17% ropivacaine with a varying dose of fentanyl. We hypothesized that the onset of analgesia would be shortened in proportion to an increase in fentanyl dose.

METHODS

Women requesting labor epidural analgesia were enrolled in this randomized controlled clinical trial. Each woman was randomly assigned to receive fentanyl 0, 50, 75, or 100 μg with 0.17% ropivacaine 12 mL. The onset and duration of analgesia, the incidence of side effects and patient satisfaction were measured.

RESULTS

Data from 102 women were analyzed. The onset of analgesia (mean ± SD) was shortened with an increasing dose of fentanyl (14.3 ± 5.4, 14.2 ± 6.5, 12.1 ± 5.1, and 8.7 ± 3.8 min with fentanyl 0, 50, 75, or 100 μg, respectively, P=0.001). The duration of analgesia was prolonged with an increasing dose of fentanyl (87.4 ± 20.8, 112.3 ± 19.5, 140.8 ± 18.8, and 143.6 ± 18.6 min with fentanyl 0, 50, 75, or 100 μg, respectively, P<0.001). The incidence of pruritus increased with an increasing dose of fentanyl (P=0.027) but there were no differences for other maternal side effects. There was a significant difference in satisfaction score among groups (P=0.009).

CONCLUSION

The addition of increasing doses of fentanyl to 0.17% ropivacaine contributed to shortened onset as well as prolonged duration of labor epidural analgesia and improved patient satisfaction.

Maternal ambulation during labor

PURPOSE OF REVIEW

To describe the recent advances in labor epidural analgesia, which may have an impact on maternal ambulation during labor.

RECENT FINDINGS

With the advent of new epidural adjuvant drugs and new epidural delivery systems, we are now able to use very low concentration local anesthetic solutions with a reduction in the total doses of local anesthetic administered. This allows a much greater preservation of lower limb motor function in the parturient, with a subsequent positive effect on maternal ambulation. Although it is well documented that maternal satisfaction scores are higher with ambulatory epidurals than with other more conventional epidural techniques, the other positive effects, such as shorter labor times, and a reduction in instrumental and cesarean delivery rates, thought to have been associated with ambulatory epidurals, have however been more difficult to prove.

SUMMARY

Since the earliest 'walking epidural' was described in the early 1990s, there has been much research into finding the ideal regional technique for labor analgesia that provides excellent analgesia with high maternal satisfaction scores while having little adverse effect on obstetric outcome. This review attempts to map the journey of the 'walking epidural' from its earliest form to its more recognizable modern day appearance.

Obstetric outcomes and maternal satisfaction in nulliparous women using patient-controlled epidural analgesia

OBJECTIVE

The purpose of this study was to compare obstetric outcomes and maternal satisfaction in nulliparous women in spontaneous labor who used patient-controlled epidural analgesia (PCEA) vs continuous epidural infusion (CEI).

STUDY DESIGN

We conducted a double-masked trial of 270 nulliparous women who were assigned randomly to 3 groups (with a concentration 0.1% bupivacaine and 2 μg/mL fentanyl): group I, CEI-only (10 mL/h); group II, CEI + PCEA (CEI 10 mL/h plus PCEA 10 mL, at 20 minutes); group III, PCEA-only (10 mL, at 20 minutes). A PCEA bolus button was given to each subject. The primary outcome was the dosage of local anesthetic that was used.

RESULTS

The total milligrams of bupivacaine that were used was less in the PCEA-only group compared with CEI: group I. 74.8 ± 36 mg; group II, 97.3 ± 53 mg; group III, 52.4 ± 42 mg (P < .001). Pain with pushing, however, was worse in the PCEA-only group. Median satisfaction scores were similar (scale, 0 [best] to 100 [worst]: group I, 0; group II, 0; group III, 0 (P = .23).

CONCLUSION

PCEA results in less anesthetic used, and maternal satisfaction remains high without a continuous infusion. Pain with pushing, however, was worse with the PCEA alone.

Patient-controlled epidural analgesia after Caesarean section: levobupivacaine 0.15% versus ropivacaine 0.15% alone or combined with fentanyl 2 µg/ml: a comparative study

INTRODUCTION

The aim of this study was to compare the postoperative analgesic efficacy of epidural ropivacaine 0.15%, levobupivacaine 0.15% and ropivacaine 0.15% plus fentanyl 2 µg/ml, used with a patient-controlled epidural analgesia (PCEA) device after Caesarean section.

MATERIAL AND METHODS

Sixty women undergoing elective Caesarean section under combined spinal-epidural anaesthesia were enrolled. Postoperatively, patients received PCEA with either ropivacaine or levobupivacaine 0.15% (basal rate 6 ml/h, bolus 5 ml/20 min), or ropivacaine 0.15% plus fentanyl 2 µg/ml (basal rate 6 ml/h, bolus 4 ml/20 min). Sympathetic and sensory level of analgesia, motor ability (Bromage 0-3), and pain scores at rest, movement and cough (VAS 0-10), haemodynamic parameters, oxygenation, side effects and total doses of local anaesthetic were documented every 6 h for 24 h. Patient satisfaction was assessed using a descriptive scale.

RESULTS

No significant difference was observed in pain scores at all time intervals. A significantly higher sympathetic and sensory blockade occurred with levobupivacaine and ropivacaine 0.15% compared to ropivacaine 0.15% plus fentanyl, with no significant difference in total local analgesic consumption at 24 h (p = 0.08). Rescue analgesic requirements did not differ between the groups (p = 0.8) while patients' satisfaction was significantly higher in the ropivacaine 0.15% plus fentanyl group (p = 0.02). Haemodynamics, oxygenation, nausea, pruritus and numbness did not differ between the groups.

CONCLUSIONS

Dilute local anaesthetic solutions provided satisfactory postoperative analgesia after Caesarean section when used with a PCEA device. The combination of ropivacaine 0.15% with fentanyl 2 µg/ml appeared superior, since it provided higher patient satisfaction with statistically equal pain scores and local anaesthetic consumption.

Epidural analgesia for labor: Current techniques

Epidural analgesia is an extremely effective and popular treatment for labor pain. In this review, we trace the history of the use of epidural analgesia and its refinements. We then outline the goals of treatment and methods used to attain those goals. The use of low concentrations of local anesthetics, combined with lipid-soluble opioids, does not impede the progress of labor or depress the newborn. The incidence of side effects is low. Maintenance of analgesia that allows patient control enhances patient satisfaction.

Effects of a continuous low-dose clonidine epidural regimen on pain, satisfaction and adverse events during labour: a randomized, double-blind, placebo-controlled trial

BACKGROUND AND OBJECTIVE

Epidural clonidine has been proposed as an adjunct for anaesthetic mixtures during labour. Administered as a bolus, clonidine may have side effects such as sedation and hypotension; its continuous infusion could be attractive in this respect. We, therefore, conducted a randomized, double-blind trial using patient-controlled epidural analgesia with a background infusion using a low dose of clonidine during labour.

METHODS

A total of 128 healthy parturients in active labour received a patient-controlled epidural analgesia solution of 0.0625% levobupivacaine and sufentanil 0.25 microg ml(-1) with or without clonidine 2 microg ml(-1). Ninety-five parturients were analysed. The pain score over time was evaluated as well as drug volume utilization; supplementation bolus and side effects were recorded. The primary endpoint was maternal satisfaction [ClinicalTrials.gov Identifier (NCT00437996)].

RESULTS

Three patients in the control group failed to achieve satisfactory epidural analgesia owing to a technical issue. Although the primary endpoint was not statistically significant, analgesia was more pronounced and obtained earlier in the clonidine group. The area under the curve for the visual analogue pain score was significantly lower in the clonidine group. In this group, hourly doses of levobupivacaine and sufentanil were reduced (13.9 +/- 4.3 vs. 16.3 ml +/- 4.0; P = 0.005) as well as rescue supplementation and pruritus incidence (18 vs. 46%; P = 0.004). Maternal blood pressure was significantly lower, over time, in the clonidine group but remained within the normal range. Sedation was similar in both groups (4.3 vs. 2.0%; not significant).

CONCLUSION

The addition of clonidine to epidural levobupivacaine and sufentanil for patient-controlled epidural analgesia in labour improved analgesia, reduced the supplementation rate and reduced pruritus without improvement in maternal satisfaction. Blood pressure was significantly lower in the clonidine group over time but without clinical consequence.

Advances in labor analgesia

The pain of childbirth is arguably the most severe pain most women will endure in their lifetimes. The pain of the early first stage of labor arises from dilation of the lower uterine segment and cervix. Pain from the late first stage and second stage of labor arises from descent of the fetus in the birth canal, resulting in distension and tearing of tissues in the vagina and perineum. An array of regional nerve blocks, systemic analgesic, and nonpharmacologic techniques are currently used for labor analgesia. Nonpharmacologic methods are commonly used, but the effectiveness of these techniques generally lacks rigorous scientific study. Continuous labor support has been shown to decrease the use of pharmacologic analgesia and shorten labor. Intradermal water injections decrease back labor pain. Neuraxial labor analgesia (most commonly epidural or combined spinal-epidural) is the most effective method of pain relief during childbirth, and the only method that provides complete analgesia without maternal or fetal sedation. Current techniques commonly combine a low dose of local anesthetic (bupivacaine or ropivacaine) with a lipid soluble opioid (fentanyl or sufentanil). Neuraxial analgesia does not increase the rate of cesarean delivery compared to systemic opioid analgesia; however, dense neuraxial analgesia may increase the risk of instrumental vaginal delivery.