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Systemic narcotics still have a significant and useful role in the management of labour pain
International Journal of Obstetric Anesthesia (2000) 9, 45–47 © 2000 Harcourt Publishers Ltd
CONTROVERSIES IN OBSTETRIC ANAESTHESIA Abstracts of a debate held on 3 March 1999 at Church House, Westminster, UK
Systemic narcotics still have a significant and useful role in the management of labour pain Proposer: Denis Walsh Senior Lecturer in Midwifery, De Montfort University, Leicester
2. Morrison C, Dutton D, Howie H, Gilmour FH. Pethidine compared with meptazinol in labour. Anaesthisia 1987; 42: 7–14. 3. Olofsson C, Ekbolm A, Ekman-Ordeberg G, Hjelm A. Lack of analgesic effect of systematically administered morphine or pethidine on labour pain. Br J Obstet Gynaecol 1996; 103: 968–972. 4. Thompson A, Hillier V. A re-evaluation of the effect of pethidine on the length of labour. J Adv Nurs 1994; 19: 448–456. 5. Way S, Way E. Opioid anaglesic and antagonists. In: Katzung B(Ed). Basic and Clinical Phamacology, 5th edition 1992; Norwalk, Prentice Hall. 6. Steer P. The methods of pain relief used In: Chamberlain G, Wraight A, Steer P (Eds). Pain and its Relief in Childbirth, Chapter 6, 1994; Churchill Livingstone, Edinburgh. 7. Chamberlain G, Wraight A, Crowley P. Home Briths: The report of the 1994 confidential enquiry by the National Birthday Trust Fund. Carnforth Lanc. 1997; The Parthenon Publishing Group 8. Department of Health. Changing Childbirth: Report of the Expert Committee on Maternity Care. 1993; London, HMSO. 9.Garcia J, Redshaw M, Fitzsimons, Keene J. First Class Delivery: Audit Commission Report on the Maternity Services Part 2 (Women’s Views). 1998; Oxford, National Perinatal Epidemiology Unit. 10. Kirkham M. Midwives and information-giving during labour. In: Robinson S, Thomspson A (Eds).Midwives, Research & Childbirth vol. 1. 1989; Chapman & Hall, London. 11. Oakley A. the Captured Womb: A history of the medical care of pregnant women. 1994; Basil Blackwood, Oxford. 12. Hodnett E. Continuity of caregivers during pregnancy and childbirth (Cochrane review). In: the Cochrane Library, Issue 4. 1998; Update Software, Oxford. 13. Flint C, Poulengeris P. The ‘Know Your Midwife’ Report. 1987; Available from 46 Peckermans Wood, London. 14. Rowley M, Hensley M, Brinsmead M, Wlodarczyk J. Continuity of care by a midwife team versus routine care during pregancy and birth: a randomised trial. Med J Aust 1995; 163: 289–293. 15. Olsen O. Meta-analysis of the safety of home birth. Birth 1997; 24: 4–13. 16. Hodnett E. Home-like versus conventional birth settings (Cochrane review). In: The Cochrane Library, Issue 4, 1998; Update Saftware, Oxford. 17. Hodnett E. Support from caregivers during childbirth (Cochrane review). In: The Cochrane Library, Issue 4, 1998; Update Software, Oxford.
There is little doubt that opioid analgesia and labour are not very compatible. There are several well researched side-effects of opiod use during labour that are detrimental to both women and neonates. Yet, opiod use in the UK during labour remains significant and most authors put this down to its availability, cost and the fact that midwives can prescribe it. However, key studies of women’s experience of maternity care in recent years reveal other factors influencing opioid use. Women have highlighted information, choice, control and continuity as important attributes of midwifery care and where these are in place, opiod use, together with other labour interventions, are significantly reduced. Operationally, these important attributes are provided when home is presented as a real choice for place of birth, when midwife-led services and birthing units are part of a package of care and when continuity of midwifery care is provided antenatally and during labour. Research findings conclude unequivocally that opiod use is diminished when these service elements are in place. Unfortunately, despite Changing Childbirth targets, much of the UK maternity services fail to deliver in these areas. Until they do, the provision of opioid analgesia for labour will remain important for many women. REFERENCES 1. Crowell M, Hill P, Humenick S. Relationships between obstetric analgesia and time of effective breastfeeding. J Nurse-Midwifery 1994; 39: 150–156.
Denis Walsh De Montfort University, Scraptoft Campus, Scraptoft, Leicester LE7 9SO, UK 45
46
International Journal of Obstetric Anesthesia
Opposer: Jackie Porter Consultant Anaesthetist, St Thomas’ Hospital, London, UK
JackiePorter, St Thomas’ Hospital, London SE1 7EH, UK
utero exposure of the fetus to opioids has also been reported to increase the risk of opioid addiction in later life.8 There are two problems with the use of intermittent i.m. pethidine. Firstly, if it is given in sufficient dose to provide good analgesia during a contraction, maternal sedation and respiratory depression between contractions, and neonatal depression after delivery, would be too great. Secondly, while plasma concentrations fluctuate about a fairly constant mean, maternal pain increases as labour progresses, reaching a peak during transition. Since neonatal depression is greatest when pethidine is given 2–3 h before delivery, for the sake of the baby we should be withholding pethidine when the mother’s pain is greatest. The more lipid soluble fentanyls have been used intravenously in some centres. Rayburn et al.9 compared i.v. fentanyl with i.v. pethidine but found no better, analgesia and similar neonatal side-effects. Ideally one needs analgesia during contractions but sufficiently low plasma concentrations between contractions to avoid sedation and respiratory depression. Remifentanil is currently the fastest-acting opioid. However, a computerised model predicting plasma concentrations following i.v. administration reported neither sufficient rapid onset nor offset of action to provide good analgesia with a low incidence of side-effects.
80 72.4
70 percent of votes
Systemic opioids can only be useful in the treatment of labour pain if their advantages outweigh their disadvantages. Ease of administration is the main advantage of systemic opioids although in the UK it is only pethidine that midwives are legally permitted to prescribe and administer. Opioids are cheap, they help some women to relax between contractions, and some reports suggest they provide adequate analgesia in labour. However, many of these studies were flawed in that some had no controls, some used independent observers to score pain or asked the mother to do so retrospectively, while others used maternal satisfaction to imply analgesic efficacy. The overwhelming majority of well designed, prospective, and mostly randomised studies continue to report that systemic opioids provide, at best, poor analgesia in labour.1,2 Maternal sedation is a prominent feature,1,2 is potentially harmful to the mother, and may detract from her experience of childbirth. Systemic opioids delay gastric emptying.3 Nausea and vomiting,4 whilst less serious, are more immediately troublesome to the mother. Pethidine increases the incidence of maternal oxygen desaturation during labour compared with no analgesia,5 while maternal catecholamine release in the presence of unrelieved pain causes uteroplacental vasoconstriction. Both effects are potentially harmful to the baby. Direct neonatal depression following systemic opioids is well documented. Large doses of pethidine decrease the Apgar score, but even after smaller doses babies have been found to have lower neurobehavioural scores, to be more sleepy, less able to develop sucking skills and therefore slower to establish breast feeding, than unmedicated controls. These effects may be prolonged for days or weeks6 due to the prolonged half life of the active metabolite norpethidine. Plasma pethidine concentration in the fetus is maximal 2–3 h after injection so in theory, if it is given within one hour of delivery neonatal effects will be minimal. However, predicting the exact time of delivery is difficult. Neonatal respiratory depression is also well documented after systemic opioids in labour and, again, this is maximal when the dose-to-delivery interval is 2–3 h, or after repeat doses to the mother.7 In
60 50
44.9
before after
51.4
40 30
24.7
20 10 2
3.7
0 for
against
abstain
Voting in the motion: Systemic narcotics still have a significant role in the management of labour pain. Voting by Brähler ICS UK Ltd.
Controversies Although no ideal analgesic agent for labour pain exists, the balance of pros and cons for other methods is far better than for parenteral opioids. Non-pharmacological methods such as TENS and massage rarely provide complete analgesia, but they are rated highly by mothers and do no harm. Entonox, too, rarely relieves all the pain but consistently scores better than pethidine; and since its side-effects are fewer and less harmful than those of pethidine its imperfect analgesia becomes acceptable. Epidural analgesia provides far superior pain relief to systemic opioids and this, along with the other advantages for mother and baby, more than balances the disadvantages. The lack of an ideal agent for pain relief in labour is not sufficient reason for the continued use of systemic opioids providing women with so little, if any, analgesia, but with so many side-effects. REFERENCES 1. Olofsson C, Ekblom A, Ekman-Ordeberg G, Granstrom L, Irestedt L. Analgesic efficacy of intravenous morphine in labour pain: a reappraisal. International Journal of Obstetric Anesthesia 1996; 5: 176–180.
47
2. Olofsson C, Ekblom A, Ekman-Ordeberg G, Hjelm A, Irestedt L. Lack of analgesic effect of systemically administered morphine or pethidine on labour pain. British J Obstet Gynaecol 1996; 103: 968–972. 3. Nimmo WS, Wilson J, Prescott LF. Narcotic analgesia and delayed gastric emptying during labour. Lancet 1975; i: 890–893. 4. Moore J, Ball HG. A sequential study of intravenous analgesic treatment during labour. Br J Anaesth 1974; 46: 365–372. 5. Porter KB, O’Brien WF, Kiefert V, Knuppel RA. Evaluation oxygen desaturation events in singleton pregnancies. J Perinatol 1992; 12: 103–106. 6. Belsey EM, Rosenblatt DB, Lieberman BA, et al. The influence of maternal analgesia on neonatal behaviour: I. Pethidine. Br J Obstet Gynaecol 1981; 88: 398–406. 7. Hamza J, Benlabed M, Orhant E, Escourrou P, CurziDascalova L, Gaultier C. Neonatal pattern of breathing during active and quiet sleep after maternal administration of meperidine. Pediatr Res 1992; 32: 412–416. 8. Jacobson B, Nyberg K, Gronbladh L et al. Opiate addiction in adult offspring through possible imprinting after obstetric treatment. Br Med J 1990; 301: 1067–1070. 9. Rayburn WF, Smith CV, Parriot JE, Woods RE. Randomized comparison of meperidine and fentanyl during labor. Obstet Gynecol 1989; 74: 604–606.
CONTROVERSIES IN OBSTETRIC ANAESTHESIA Abstracts of a debate held on 3 March 1999 at Church House, Westminster, UK
Systemic narcotics still have a significant and useful role in the management of labour pain Proposer: Denis Walsh Senior Lecturer in Midwifery, De Montfort University, Leicester
2. Morrison C, Dutton D, Howie H, Gilmour FH. Pethidine compared with meptazinol in labour. Anaesthisia 1987; 42: 7–14. 3. Olofsson C, Ekbolm A, Ekman-Ordeberg G, Hjelm A. Lack of analgesic effect of systematically administered morphine or pethidine on labour pain. Br J Obstet Gynaecol 1996; 103: 968–972. 4. Thompson A, Hillier V. A re-evaluation of the effect of pethidine on the length of labour. J Adv Nurs 1994; 19: 448–456. 5. Way S, Way E. Opioid anaglesic and antagonists. In: Katzung B(Ed). Basic and Clinical Phamacology, 5th edition 1992; Norwalk, Prentice Hall. 6. Steer P. The methods of pain relief used In: Chamberlain G, Wraight A, Steer P (Eds). Pain and its Relief in Childbirth, Chapter 6, 1994; Churchill Livingstone, Edinburgh. 7. Chamberlain G, Wraight A, Crowley P. Home Briths: The report of the 1994 confidential enquiry by the National Birthday Trust Fund. Carnforth Lanc. 1997; The Parthenon Publishing Group 8. Department of Health. Changing Childbirth: Report of the Expert Committee on Maternity Care. 1993; London, HMSO. 9.Garcia J, Redshaw M, Fitzsimons, Keene J. First Class Delivery: Audit Commission Report on the Maternity Services Part 2 (Women’s Views). 1998; Oxford, National Perinatal Epidemiology Unit. 10. Kirkham M. Midwives and information-giving during labour. In: Robinson S, Thomspson A (Eds).Midwives, Research & Childbirth vol. 1. 1989; Chapman & Hall, London. 11. Oakley A. the Captured Womb: A history of the medical care of pregnant women. 1994; Basil Blackwood, Oxford. 12. Hodnett E. Continuity of caregivers during pregnancy and childbirth (Cochrane review). In: the Cochrane Library, Issue 4. 1998; Update Software, Oxford. 13. Flint C, Poulengeris P. The ‘Know Your Midwife’ Report. 1987; Available from 46 Peckermans Wood, London. 14. Rowley M, Hensley M, Brinsmead M, Wlodarczyk J. Continuity of care by a midwife team versus routine care during pregancy and birth: a randomised trial. Med J Aust 1995; 163: 289–293. 15. Olsen O. Meta-analysis of the safety of home birth. Birth 1997; 24: 4–13. 16. Hodnett E. Home-like versus conventional birth settings (Cochrane review). In: The Cochrane Library, Issue 4, 1998; Update Saftware, Oxford. 17. Hodnett E. Support from caregivers during childbirth (Cochrane review). In: The Cochrane Library, Issue 4, 1998; Update Software, Oxford.
There is little doubt that opioid analgesia and labour are not very compatible. There are several well researched side-effects of opiod use during labour that are detrimental to both women and neonates. Yet, opiod use in the UK during labour remains significant and most authors put this down to its availability, cost and the fact that midwives can prescribe it. However, key studies of women’s experience of maternity care in recent years reveal other factors influencing opioid use. Women have highlighted information, choice, control and continuity as important attributes of midwifery care and where these are in place, opiod use, together with other labour interventions, are significantly reduced. Operationally, these important attributes are provided when home is presented as a real choice for place of birth, when midwife-led services and birthing units are part of a package of care and when continuity of midwifery care is provided antenatally and during labour. Research findings conclude unequivocally that opiod use is diminished when these service elements are in place. Unfortunately, despite Changing Childbirth targets, much of the UK maternity services fail to deliver in these areas. Until they do, the provision of opioid analgesia for labour will remain important for many women. REFERENCES 1. Crowell M, Hill P, Humenick S. Relationships between obstetric analgesia and time of effective breastfeeding. J Nurse-Midwifery 1994; 39: 150–156.
Denis Walsh De Montfort University, Scraptoft Campus, Scraptoft, Leicester LE7 9SO, UK 45
46
International Journal of Obstetric Anesthesia
Opposer: Jackie Porter Consultant Anaesthetist, St Thomas’ Hospital, London, UK
JackiePorter, St Thomas’ Hospital, London SE1 7EH, UK
utero exposure of the fetus to opioids has also been reported to increase the risk of opioid addiction in later life.8 There are two problems with the use of intermittent i.m. pethidine. Firstly, if it is given in sufficient dose to provide good analgesia during a contraction, maternal sedation and respiratory depression between contractions, and neonatal depression after delivery, would be too great. Secondly, while plasma concentrations fluctuate about a fairly constant mean, maternal pain increases as labour progresses, reaching a peak during transition. Since neonatal depression is greatest when pethidine is given 2–3 h before delivery, for the sake of the baby we should be withholding pethidine when the mother’s pain is greatest. The more lipid soluble fentanyls have been used intravenously in some centres. Rayburn et al.9 compared i.v. fentanyl with i.v. pethidine but found no better, analgesia and similar neonatal side-effects. Ideally one needs analgesia during contractions but sufficiently low plasma concentrations between contractions to avoid sedation and respiratory depression. Remifentanil is currently the fastest-acting opioid. However, a computerised model predicting plasma concentrations following i.v. administration reported neither sufficient rapid onset nor offset of action to provide good analgesia with a low incidence of side-effects.
80 72.4
70 percent of votes
Systemic opioids can only be useful in the treatment of labour pain if their advantages outweigh their disadvantages. Ease of administration is the main advantage of systemic opioids although in the UK it is only pethidine that midwives are legally permitted to prescribe and administer. Opioids are cheap, they help some women to relax between contractions, and some reports suggest they provide adequate analgesia in labour. However, many of these studies were flawed in that some had no controls, some used independent observers to score pain or asked the mother to do so retrospectively, while others used maternal satisfaction to imply analgesic efficacy. The overwhelming majority of well designed, prospective, and mostly randomised studies continue to report that systemic opioids provide, at best, poor analgesia in labour.1,2 Maternal sedation is a prominent feature,1,2 is potentially harmful to the mother, and may detract from her experience of childbirth. Systemic opioids delay gastric emptying.3 Nausea and vomiting,4 whilst less serious, are more immediately troublesome to the mother. Pethidine increases the incidence of maternal oxygen desaturation during labour compared with no analgesia,5 while maternal catecholamine release in the presence of unrelieved pain causes uteroplacental vasoconstriction. Both effects are potentially harmful to the baby. Direct neonatal depression following systemic opioids is well documented. Large doses of pethidine decrease the Apgar score, but even after smaller doses babies have been found to have lower neurobehavioural scores, to be more sleepy, less able to develop sucking skills and therefore slower to establish breast feeding, than unmedicated controls. These effects may be prolonged for days or weeks6 due to the prolonged half life of the active metabolite norpethidine. Plasma pethidine concentration in the fetus is maximal 2–3 h after injection so in theory, if it is given within one hour of delivery neonatal effects will be minimal. However, predicting the exact time of delivery is difficult. Neonatal respiratory depression is also well documented after systemic opioids in labour and, again, this is maximal when the dose-to-delivery interval is 2–3 h, or after repeat doses to the mother.7 In
60 50
44.9
before after
51.4
40 30
24.7
20 10 2
3.7
0 for
against
abstain
Voting in the motion: Systemic narcotics still have a significant role in the management of labour pain. Voting by Brähler ICS UK Ltd.
Controversies Although no ideal analgesic agent for labour pain exists, the balance of pros and cons for other methods is far better than for parenteral opioids. Non-pharmacological methods such as TENS and massage rarely provide complete analgesia, but they are rated highly by mothers and do no harm. Entonox, too, rarely relieves all the pain but consistently scores better than pethidine; and since its side-effects are fewer and less harmful than those of pethidine its imperfect analgesia becomes acceptable. Epidural analgesia provides far superior pain relief to systemic opioids and this, along with the other advantages for mother and baby, more than balances the disadvantages. The lack of an ideal agent for pain relief in labour is not sufficient reason for the continued use of systemic opioids providing women with so little, if any, analgesia, but with so many side-effects. REFERENCES 1. Olofsson C, Ekblom A, Ekman-Ordeberg G, Granstrom L, Irestedt L. Analgesic efficacy of intravenous morphine in labour pain: a reappraisal. International Journal of Obstetric Anesthesia 1996; 5: 176–180.
47
2. Olofsson C, Ekblom A, Ekman-Ordeberg G, Hjelm A, Irestedt L. Lack of analgesic effect of systemically administered morphine or pethidine on labour pain. British J Obstet Gynaecol 1996; 103: 968–972. 3. Nimmo WS, Wilson J, Prescott LF. Narcotic analgesia and delayed gastric emptying during labour. Lancet 1975; i: 890–893. 4. Moore J, Ball HG. A sequential study of intravenous analgesic treatment during labour. Br J Anaesth 1974; 46: 365–372. 5. Porter KB, O’Brien WF, Kiefert V, Knuppel RA. Evaluation oxygen desaturation events in singleton pregnancies. J Perinatol 1992; 12: 103–106. 6. Belsey EM, Rosenblatt DB, Lieberman BA, et al. The influence of maternal analgesia on neonatal behaviour: I. Pethidine. Br J Obstet Gynaecol 1981; 88: 398–406. 7. Hamza J, Benlabed M, Orhant E, Escourrou P, CurziDascalova L, Gaultier C. Neonatal pattern of breathing during active and quiet sleep after maternal administration of meperidine. Pediatr Res 1992; 32: 412–416. 8. Jacobson B, Nyberg K, Gronbladh L et al. Opiate addiction in adult offspring through possible imprinting after obstetric treatment. Br Med J 1990; 301: 1067–1070. 9. Rayburn WF, Smith CV, Parriot JE, Woods RE. Randomized comparison of meperidine and fentanyl during labor. Obstet Gynecol 1989; 74: 604–606.