Epidural versus non-epidural or no analgesia for pain management in labour

Abstract

Background: Epidural analgesia is a central nerve block technique achieved by injection of a local anaesthetic close to the nerves that transmit pain, and is widely used as a form of pain relief in labour. However, there are concerns about unintended adverse effects on the mother and infant. This is an update of an existing Cochrane Review (Epidural versus non-epidural or no analgesia in labour), last published in 2011.

Objectives: To assess the effectiveness and safety of all types of epidural analgesia, including combined-spinal-epidural (CSE) on the mother and the baby, when compared with non-epidural or no pain relief during labour.

Search methods: We searched Cochrane Pregnancy and Childbirth's Trials Register (ClinicalTrials.gov), the WHO International Clinical Trials Registry Platform (ICTRP) (30 April 2017), and reference lists of retrieved studies.

Selection criteria: Randomised controlled trials comparing all types of epidural with any form of pain relief not involving regional blockade, or no pain relief in labour. We have not included cluster-randomised or quasi-randomised trials in this update.

Data collection and analysis: Two review authors independently assessed trials for inclusion and risks of bias, extracted data and checked them for accuracy. We assessed selected outcomes using the GRADE approach.

Main results: Fifty-two trials met the inclusion criteria and we have included data from 40 trials, involving over 11,000 women. Four trials included more than two arms. Thirty-four trials compared epidural with opioids, seven compared epidural with no analgesia, one trial compared epidural with acu-stimulation, one trial compared epidural with inhaled analgesia, and one trial compared epidural with continuous midwifery support and other analgesia. Risks of bias varied throughout the included studies; six out of 40 studies were at high or unclear risk of bias for every bias domain, while most studies were at high or unclear risk of detection bias. Quality of the evidence assessed using GRADE ranged from moderate to low quality.Pain intensity as measured using pain scores was lower in women with epidural analgesia when compared to women who received opioids (standardised mean difference -2.64, 95% confidence interval (CI) -4.56 to -0.73; 1133 women; studies = 5; I2 = 98%; low-quality evidence) and a higher proportion were satisfied with their pain relief, reporting it to be "excellent or very good" (average risk ratio (RR) 1.47, 95% CI 1.03 to 2.08; 1911 women; studies = 7; I2 = 97%; low-quality evidence). There was substantial statistical heterogeneity in both these outcomes. There was a substantial decrease in the need for additional pain relief in women receiving epidural analgesia compared with opioid analgesia (average RR 0.10, 95% CI 0.04 to 0.25; 5099 women; studies = 16; I2 = 73%; Tau2 = 1.89; Chi2 = 52.07 (P < 0.00001)). More women in the epidural group experienced assisted vaginal birth (RR 1.44, 95% CI 1.29 to 1.60; 9948 women; studies = 30; low-quality evidence). A post hoc subgroup analysis of trials conducted after 2005 showed that this effect is negated when trials before 2005 are excluded from this analysis (RR 1.19, 95% CI 0.97 to 1.46). There was no difference between caesarean section rates (RR 1.07, 95% CI 0.96 to 1.18; 10,350 women; studies = 33; moderate-quality evidence), and maternal long-term backache (RR 1.00, 95% CI 0.89 to 1.12; 814 women; studies = 2; moderate-quality evidence). There were also no clear differences between groups for the neonatal outcomes, admission to neonatal intensive care unit (RR 1.03, 95% CI 0.95 to 1.12; 4488 babies; studies = 8; moderate-quality evidence) and Apgar score less than seven at five minutes (RR 0.73, 95% CI 0.52 to 1.02; 8752 babies; studies = 22; low-quality evidence). We downgraded the evidence for study design limitations, inconsistency, imprecision in effect estimates, and possible publication bias.Side effects were reported in both epidural and opioid groups. Women with epidural experienced more hypotension, motor blockade, fever, and urinary retention. They also had longer first and second stages of labour, and were more likely to have oxytocin augmentation than the women in the opioid group. Women receiving epidurals had less risk of respiratory depression requiring oxygen, and were less likely to experience nausea and vomiting than women receiving opioids. Babies born to women in the epidural group were less likely to have received naloxone. There was no clear difference between groups for postnatal depression, headache, itching, shivering, or drowsiness. Maternal morbidity and long-term neonatal outcomes were not reported.Epidural analgesia resulted in less reported pain when compared with placebo or no treatment, and with acu-stimulation. Pain intensity was not reported in the trials that compared epidural with inhaled analgesia, or continuous support. Few trials reported on serious maternal side effects.

Authors' conclusions: Low-quality evidence shows that epidural analgesia may be more effective in reducing pain during labour and increasing maternal satisfaction with pain relief than non-epidural methods. Although overall there appears to be an increase in assisted vaginal birth when women have epidural analgesia, a post hoc subgroup analysis showed this effect is not seen in recent studies (after 2005), suggesting that modern approaches to epidural analgesia in labour do not affect this outcome. Epidural analgesia had no impact on the risk of caesarean section or long-term backache, and did not appear to have an immediate effect on neonatal status as determined by Apgar scores or in admissions to neonatal intensive care. Further research may be helpful to evaluate rare but potentially severe adverse effects of epidural analgesia and non-epidural analgesia on women in labour and long-term neonatal outcomes.

Conflict of interest statement

Millicent Anim‐Somuah: None known

Rebecca MD Smyth: None known

Allan M Cyna: None known

Anna Cuthbert: I am a research associate working in the editorial base of Cochrane Pregnancy and Childbirth. I am employed by the University of Liverpool to work as a research associate in Cochrane Pregnancy and Childbirth (who receives infrastructure funding from the NIHR, UK).

Figures

1

Study flow diagram.

2

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

3

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.

4

Funnel plot of comparison: 1 Epidural versus opioids, outcome: 1.12 Assisted vaginal birth.

5

Funnel plot of comparison: 1 Epidural versus opioids, outcome: 1.13 Caesarean section.

6

Funnel plot of comparison: 1 Epidural versus opioids, outcome: 1.35 Apgar score less than 7 at 5 minutes.

1.1. Analysis

Comparison 1 Epidural versus opioids, Outcome 1 Pain score in labour.

1.2. Analysis

Comparison 1 Epidural versus opioids, Outcome 2 Pain intensity severe or intolerable.

1.3. Analysis

Comparison 1 Epidural versus opioids, Outcome 3 Woman's perception of pain relief in labour.

1.4. Analysis

Comparison 1 Epidural versus opioids, Outcome 4 Woman's perception of pain relief during first stage of labour.

1.5. Analysis

Comparison 1 Epidural versus opioids, Outcome 5 Woman's perception of pain relief during the second stage of labour.

1.6. Analysis

Comparison 1 Epidural versus opioids, Outcome 6 Satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

1.7. Analysis

Comparison 1 Epidural versus opioids, Outcome 7 Satisfaction with pain relief in labour ‐ continuous data.

1.8. Analysis

Comparison 1 Epidural versus opioids, Outcome 8 Time of administration of pain relief to time pain relief was satisfactory (minutes).

1.9. Analysis

Comparison 1 Epidural versus opioids, Outcome 9 Perceived feeling of poor control in labour.

1.10. Analysis

Comparison 1 Epidural versus opioids, Outcome 10 Satisfaction with childbirth experience ‐ proportion rating satisfied to very satisfied.

1.11. Analysis

Comparison 1 Epidural versus opioids, Outcome 11 Need for additional means of pain relief.

1.12. Analysis

Comparison 1 Epidural versus opioids, Outcome 12 Assisted vaginal birth.

1.13. Analysis

Comparison 1 Epidural versus opioids, Outcome 13 Caesarean section.

1.14. Analysis

Comparison 1 Epidural versus opioids, Outcome 14 Long‐term backache.

1.15. Analysis

Comparison 1 Epidural versus opioids, Outcome 15 Hypotension as defined by trial authors.

1.16. Analysis

Comparison 1 Epidural versus opioids, Outcome 16 Postnatal depression (authors definition, on medication, or self‐reported).

1.17. Analysis

Comparison 1 Epidural versus opioids, Outcome 17 Motor blockade.

1.18. Analysis

Comparison 1 Epidural versus opioids, Outcome 18 Respiratory depression requiring oxygen administration.

1.19. Analysis

Comparison 1 Epidural versus opioids, Outcome 19 Headache.

1.20. Analysis

Comparison 1 Epidural versus opioids, Outcome 20 Perineal trauma requiring suturing.

1.21. Analysis

Comparison 1 Epidural versus opioids, Outcome 21 Nausea and vomiting.

1.22. Analysis

Comparison 1 Epidural versus opioids, Outcome 22 Itch.

1.23. Analysis

Comparison 1 Epidural versus opioids, Outcome 23 Fever > 38 º C.

1.24. Analysis

Comparison 1 Epidural versus opioids, Outcome 24 Shivering.

1.25. Analysis

Comparison 1 Epidural versus opioids, Outcome 25 Drowsiness.

1.26. Analysis

Comparison 1 Epidural versus opioids, Outcome 26 Urinary retention.

1.27. Analysis

Comparison 1 Epidural versus opioids, Outcome 27 Catheterisation during labour.

1.28. Analysis

Comparison 1 Epidural versus opioids, Outcome 28 Malposition.

1.29. Analysis

Comparison 1 Epidural versus opioids, Outcome 29 Surgical amniotomy.

1.30. Analysis

Comparison 1 Epidural versus opioids, Outcome 30 Acidosis defined by cord arterial pH

1.31. Analysis

Comparison 1 Epidural versus opioids, Outcome 31 Acidosis defined by cord arterial pH

1.32. Analysis

Comparison 1 Epidural versus opioids, Outcome 32 Naloxone administration.

1.33. Analysis

Comparison 1 Epidural versus opioids, Outcome 33 Meconium staining of liquor.

1.34. Analysis

Comparison 1 Epidural versus opioids, Outcome 34 Neonatal intensive care unit admission.

1.35. Analysis

Comparison 1 Epidural versus opioids, Outcome 35 Apgar score less than 7 at 5 minutes.

1.36. Analysis

Comparison 1 Epidural versus opioids, Outcome 36 Length of first stage of labour (minutes).

1.37. Analysis

Comparison 1 Epidural versus opioids, Outcome 37 Length of second stage of labour (minutes).

1.38. Analysis

Comparison 1 Epidural versus opioids, Outcome 38 Oxytocin augmentation.

1.39. Analysis

Comparison 1 Epidural versus opioids, Outcome 39 Caesarean section for fetal distress.

1.40. Analysis

Comparison 1 Epidural versus opioids, Outcome 40 Caesarean section for dystocia.

1.41. Analysis

Comparison 1 Epidural versus opioids, Outcome 41 Sensitivity analysis ‐ allocation concealment: Maternal satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

1.42. Analysis

Comparison 1 Epidural versus opioids, Outcome 42 Sensitivity analysis ‐ incomplete outcome data: Maternal satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

1.43. Analysis

Comparison 1 Epidural versus opioids, Outcome 43 Sensitivity analysis ‐ allocation concealment: Need for additional means of pain relief.

1.44. Analysis

Comparison 1 Epidural versus opioids, Outcome 44 Sensitivity analysis ‐ incomplete outcome data: Need for additional means of pain relief.

2.1. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 1 Pain score in labour.

2.2. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 2 Woman's perception of pain relief during first stage of labour.

2.3. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 3 Woman's perception of pain relief during the second stage of labour.

2.4. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 4 Pain intensity.

2.5. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 5 Satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

2.6. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 6 Perceived feeling of poor control in labour.

2.7. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 7 Need for additional means of pain relief.

2.8. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 8 Instrumental delivery.

2.9. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 9 Caesarean section.

2.10. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 10 Motor blockade.

2.11. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 11 Headache.

2.12. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 12 Perineal trauma requiring suturing.

2.13. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 13 Nausea and vomiting.

2.14. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 14 Itch.

2.15. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 15 Fever > 38 º C.

2.16. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 16 Shivering.

2.17. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 17 Drowsiness.

2.18. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 18 Urinary retention.

2.19. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 19 Apgar score less than 7 at 5 minutes.

2.20. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 20 Length of first stage of labour (minutes).

2.21. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 21 Length of second stage of labour (minutes).

2.22. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 22 Oxytocin augmentation.

2.23. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 23 Caesarean section for fetal distress.

2.24. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 24 Caesarean section for dystocia.

2.25. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 25 Sensitivity analysis ‐ allocation concealment: Need for additional means of pain relief.

2.26. Analysis

Comparison 2 Epidural versus placebo/no treatment, Outcome 26 Sensitivity analysis ‐ incomplete outcome data: Need for additional means of pain relief.

3.1. Analysis

Comparison 3 Epidural versus TENS, Outcome 1 Maternal pain score in labour.

3.2. Analysis

Comparison 3 Epidural versus TENS, Outcome 2 Instrumental delivery.

3.3. Analysis

Comparison 3 Epidural versus TENS, Outcome 3 Caesarean section.

3.4. Analysis

Comparison 3 Epidural versus TENS, Outcome 4 Hypotension as defined by trial authors.

3.5. Analysis

Comparison 3 Epidural versus TENS, Outcome 5 Urinary retention.

3.6. Analysis

Comparison 3 Epidural versus TENS, Outcome 6 Nausea and vomiting.

3.7. Analysis

Comparison 3 Epidural versus TENS, Outcome 7 Length of second stage of labour (minutes).

3.8. Analysis

Comparison 3 Epidural versus TENS, Outcome 8 Oxytocin augmentation.

4.1. Analysis

Comparison 4 Epidural versus inhaled analgesia, Outcome 1 Maternal satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

4.2. Analysis

Comparison 4 Epidural versus inhaled analgesia, Outcome 2 Caesarean section.

5.1. Analysis

Comparison 5 Epidural versus continuous support, Outcome 1 Satisfaction with pain relief in labour ‐ proportion rating excellent or very good.

5.2. Analysis

Comparison 5 Epidural versus continuous support, Outcome 2 Need for additional means of pain relief.

5.3. Analysis

Comparison 5 Epidural versus continuous support, Outcome 3 Instrumental delivery.

5.4. Analysis

Comparison 5 Epidural versus continuous support, Outcome 4 Caesarean section.

5.5. Analysis

Comparison 5 Epidural versus continuous support, Outcome 5 Long‐term backache.

5.6. Analysis

Comparison 5 Epidural versus continuous support, Outcome 6 Headache.

5.7. Analysis

Comparison 5 Epidural versus continuous support, Outcome 7 Nausea and vomiting.

5.8. Analysis

Comparison 5 Epidural versus continuous support, Outcome 8 Cathetherisation during labour.

5.9. Analysis

Comparison 5 Epidural versus continuous support, Outcome 9 Apgar score less than 7 at 5 minutes.