Skip to main content Accessibility help

We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.

Close cookie message
×
Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-10T11:51:30.844Z Has data issue: false hasContentIssue false

13 - Drugs in obstetrics

Published online by Cambridge University Press:  21 August 2009

Alexander Heazell  and
John Clift
By
Lisa Penny
Alexander Heazell
Affiliation:
University of Manchester
John Clift
Affiliation:
City Hospital, Birmingham
Lisa Penny
Affiliation:
Specialist Registrar in Anaesthetics and Intensive Care, University Hospitals, Birmingham, Queen Elizabeth Hospital, Birmingham, UK
Get access

Summary

Introduction

Drugs used in obstetrics merit special mention because they have their effects on two patients rather than one. Pharmacologically they are of particular interest because they may be transferred across, and metabolised by, another organ, the placenta. It is important for the anaesthetist to have an understanding of the drugs commonly used by obstetricians, the evidence for them and their interface with anaesthetics.

Drugs to increase uterine contractions

Indications

  • Acceleration/augmentation of labour

  • To minimise risk of postpartum haemorrhage (PPH)

  • Treatment of PPH

Oxytocin

  • In the UK a synthetic oxytocin is manufactured under the name syntocinion. It is a nonapeptide used to induce and augment labour and also to minimise blood loss post-delivery.

  • It is thought to act by binding to myometrial cell receptors and increasing smooth muscle contractility.

  • Guidelines from the Royal College of Obstetricians and Gynaecologists recommend that to induce or accelerate labour, oxytocin is given intravenously starting at a rate of 1–2 miU/min, titrated to uterine contractions and increasing every 30 minutes to a maximum of 32 miU/min.

  • It may also be given as a dose of 5 units slowly after delivery of baby during Caesarean section.

  • Can be given as an infusion of 10 U/hr for the treatment prevention of PPH secondary to uterine atony. This is normally for a period of 4 hours.

  • Its main adverse effect is the relaxation of vascular smooth muscle causing hypotension and a reflex tachycardia: this is potentiated in vasoconstricted states such as pre-eclampsia and hypovolaemia. It also has an antidiuretic effect, which can lead to water intoxication in large doses. Other side effects include nausea, vomiting and rashes.

Keywords

antihypertensive agentsatosibanbeta2-adrenergic agonistsnifedipineoxytocinprostaglandinssteroidsobstetricstocolyticsuterine hyperstimulation
Type
Chapter
Information
Obstetrics for Anaesthetists , pp. 140 - 148
Publisher: Cambridge University Press
Print publication year: 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

National Institute for Health and Clinical Excellence. Inherited Clinical Guideline D. Induction of Labour (London: Department of Health, 2001).
Gülmezoglu, A., Forna, F., Villar, J. and Hofmeyr, G., Prostaglandins for preventing postpartum haemorrhage. Cochrane Database Syst. Rev., 3 (2007), CD000494. DOI 10.1002/14651858.CD000494.pub2.Google Scholar
Langenbach, C., Misoprostol in preventing postpartum haemorrhage: a meta-analysis. Int. J. Gynecol. Obstet., 92 (2006), 10–18.Google Scholar
O'Brien, P., El-Refaey, H., Gordon, A., Geary, M. and Rodeck, C. H., Rectally administered misoprostol for the treatment of postpartum hemorrhage unresponsive to oxytocin and ergometrine: a descriptive study. Obstet. Gynecol, 92:2 (1998), 212–4.Google Scholar
Lokugamage, A. U., Sullivan, K. R., Niculescu, I.et al. A randomized study comparing rectally administered misoprostol versus Syntometrine combined with an oxytocin infusion for the cessation of primary postpartum haemorrhage. Acta Obstet. Gynecol. Scand., 80:9 (2001), 835–9.Google Scholar
Melin, P., Oxytocin antagonists in preterm labour and delivery. Bailliere's Clin. Obstet. Gynaecol., 7 (1993), 577–600.Google Scholar
Tsatsaris, V., Patapsonis, D., Goffinet, F., Dekker, G. and Carbonne, B., Tocolysis with nifedipine or beta-adrenergic agonists: a meta-analysis. Obstet. Gynecol. 97 (2001), 840–7.Google Scholar
Gaunekar, N. and Crowther, C. A., Maintenance therapy with calcium channel blockers for preventing preterm birth after threatened preterm labour. Cochrane Database Syst. Rev., 3 (2004), CD004071. DOI 10.1002/14651858.CD004071.pub2.Google Scholar
Royal College of Obstetricians and Gynaecologists, Tocolytic Drugs for Women in Preterm Labour. Guideline Number 1B (London: Royal College of Obstetricians and Gynaecologists Press, 2002).
Royal College of Obstetricians and Gynaecologists, Anti-D Immunoglobulin for Rhesus Prophylaxis. Guideline Number 22 (London: Royal College of Obstetricians and Gynaecologists Press, 2002).
National Institute for Health and Clinical Excellence, The Use of Routine Antenatal Anti-D Prophylaxis for Rhesus-D Negative Women. Technology Appraisal Guidance number 41 (London: Department of Health, 2002).
The Magpie Trial Collaboration Group. Do women with pre-eclampsia, and their babies, benefit from magnesium sulphate? The Magpie Trial: a randomised placebo-controlled trial. Lancet, 359 (2002), 1877–90.
Abalos, E., Duley, L., Steyn, D. W. and Henderson-Smart, D. J., Anti-hypertensive drug therapy for mild–moderate hypertension during pregnancy. Cochrane Database Syst. Rev., 1 (2007), CD002252. DOI 10.1002/14651858.CD002252.pub2.Google Scholar
Magee, L. A. and Duley, L., Oral beta-blockers for mild to moderate hypertension during pregnancy. Cochrane Database Syst. Rev., 1 (2003), CD002863. DOI 10.1002/14651858.CD002863.pub2.Google Scholar
Duley, L., Henderson-Smart, D. J. and Meher, S., Drugs for treatment of very high blood pressure during pregnancy. Cochrane Database Syst. Rev., 3 (2006), CD001449. DOI 10.1002/14651858. CD001449.pub2.Google Scholar
Royal College of Obstetricians and Gynaecologists, Antenatal Corticosteroids to Prevent Respiratory Distress Syndrome. Guideline Number 7 (London: Royal College of Obstetricians and Gynaecologists Press, 2004).
Guinn, D. A., Atkinson, M. W., Sullivan, L.et al., Single vs weekly courses of antenatal corticosteroids for women at risk of preterm labour: a randomised controlled trial. JAMA, 286:13 (2001), 1581–7.Google Scholar
Kay, H. H., Bird, I. M., Coe, C. L. and Dudley, D. J., Antenatal steroid treatment and adverse fetal effects: what is the evidence?J. Soc. Gynecol. Investig., 7:5 (2000), 269–78.Google Scholar
K. G. Eagland and G. M. Cooper, Drugs acting on the uterus. Bulletin 10 The Royal College of Anaesthetists November 2001, 473–6.
Roberts, J. M.Preventing and treating eclamptic seizures. BMJ, 325 (2002), 609–10.Google Scholar
Duley, L and Neilson, J. P.Magnesium sulphate and pre-eclampsia. BMJ, 319 (1999), 3–4.Google Scholar

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

  • Drugs in obstetrics
    • By Lisa Penny, Specialist Registrar in Anaesthetics and Intensive Care, University Hospitals, Birmingham, Queen Elizabeth Hospital, Birmingham, UK
  • Alexander Heazell, University of Manchester, John Clift
  • Book: Obstetrics for Anaesthetists
  • Online publication: 21 August 2009
  • Chapter DOI: https://doi.org/10.1017/CBO9780511544569.015
Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

  • Drugs in obstetrics
    • By Lisa Penny, Specialist Registrar in Anaesthetics and Intensive Care, University Hospitals, Birmingham, Queen Elizabeth Hospital, Birmingham, UK
  • Alexander Heazell, University of Manchester, John Clift
  • Book: Obstetrics for Anaesthetists
  • Online publication: 21 August 2009
  • Chapter DOI: https://doi.org/10.1017/CBO9780511544569.015
Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

  • Drugs in obstetrics
    • By Lisa Penny, Specialist Registrar in Anaesthetics and Intensive Care, University Hospitals, Birmingham, Queen Elizabeth Hospital, Birmingham, UK
  • Alexander Heazell, University of Manchester, John Clift
  • Book: Obstetrics for Anaesthetists
  • Online publication: 21 August 2009
  • Chapter DOI: https://doi.org/10.1017/CBO9780511544569.015
Available formats
×