Graduate Certificate in Midwifery

My graduation certificate has arrived, and I have posted the application for endorsement of my registration.

It has been a long journey that I probably would not have taken of my own volition.

Once the paperwork has been processed, I will be a midwife prescriber, and will have my own prescription pads.  The number of scheduled medicines that I will want to use is likely to be very small: syntocinon, syntometrine, maxalon, benzyl penicillin.

post script 16/10/13
I sent the paperwork off last Friday, and got a phone call today telling me that the notation as a prescriber is now on the register.  So fast!

I have set up a new facebook group for midwife prescribers and others who are interested. 

Journal: the pharmacology of uterotonics

Today I have reflected on bleeding after birth.


In preparation for this study I accessed MIMS online, to revise the pharmacology of the uterotonics that midwives and doctors use in the third stage of labour.  These drugs are Syntocinon, Syntometrine, and Misoprostol. A site linked to MIMS, with consumer information about medicines, is myDr.com.au . Readers may search for other information online, but I have linked each of these drugs to the myDr site to allow easy access to consumer information.

My study method when reading copious pages of information is to look for flashing red lights, which are anything that I didn't know, didn't expect, or am surprised about.  Today's study has provided me with a few flashing red lights.



Before revising the pharmacology of these drugs, I have reviewed the evidence around bleeding and the management of the third stage.  The unavoidable issue that arises for me is that I do not agree with national and international experts who recommend routine active management of third stage for all women.  My disagreement relates to women in my world: women who are well, and who intend to give birth within unmedicated normal physiological processes, and for whom there is a very low risk of morbidity as a result of post partum haemorrhage.  This is an informed position, which I have been studying since I began private midwifery practice in 1993, and realised that there is something unique and protective about protecting, promoting and supporting natural processes in birth and the nurture of the infant.  The principle I follow was set down by World Health Organisation:

"In normal birth there should be a valid reason to interfere with the natural process."

WHO (1996) Care in Normal Birth: A practical guide. 

When I attend a birth at home I carry an ampoule of Syntocinon®10 units, and an ampoule of Syntometrine®.  I use an intramuscular injection of one or both of these drugs if indicated.  A more recent development in preventing obstetric haemorrhage, developed for use particularly in resource-poor countries, is Misoprostol.  I have used this drug in hospital births, but do not carry it.

A few selected facts:

Syntocinon® is a synthetic oxytocin.  Oxytocin is that wonderful love hormone that causes the uterus to contract, and the breast to yield its milk in abundance. 

Pharmacodynamics:

... stimulates the smooth muscle of the uterus, producing rhythmic contractions, particularly towards the end of pregnancy, during labour, after delivery and in the puerperium, i.e. at times when the number of specific oxytocin receptors in the myometrium is increased.... being a polypeptide, is largely inactivated in the alimentary tract and therefore virtually ineffective when ingested. (MIMS)

Pharmacokinetics: 
Plasma levels and onset/ duration of effect. Intravenous injection and intramuscular injection. When administered by intravenous or intramuscular injection for prevention or treatment of postpartum haemorrhage, Syntocinon acts rapidly, with a latency period of less than one minute by intravenous injection and of two to four minutes by intramuscular injection. The oxytocic response lasts for 30 to 60 minutes after intramuscular administration and possibly less after intravenous injection. Distribution. Oxytocin distributes throughout the extracellular fluid, with minimal amounts reaching the fetus. ... Plasma protein binding is very low. Oxytocin may be found in small quantities in mothers' breast milk.
Biotransformation. A glycoprotein aminopeptidase, oxytocinase, is produced during pregnancy and appears in the plasma. It is capable of degrading oxytocin. Enzyme activity increases gradually until term approaches, at which time it rises steeply to high levels. Enzyme activity then declines after delivery. Enzyme activity in the placenta and in the uterine tissue is also high during this period. There is little or no degradation of oxytocin by plasma in men, nonpregnant women or cord blood.
Excretion. The relative ease with which the rate and force of uterine contractions can be regulated by the intravenous infusion of Syntocinon is due to the short half-life of oxytocin. Values reported by various investigators range from 3 to 20 minutes. Removal of oxytocin from plasma is accomplished mainly by the liver and the kidneys. The metabolic clearance rate amounts to about 20 mL/kg/minute in men as well as in pregnant women. Less than 1% of a given dose is excreted unchanged in the urine.(MIMS)

Precautions: ...
Third stage of labour and puerperium. When Syntocinon is used for prevention or treatment of uterine haemorrhage, rapid intravenous bolus injection of oxytocin at high doses should be avoided, as it may cause acute short lasting hypotension accompanied by flushing and reflex tachycardia. These rapid haemodynamic changes may result in myocardial ischemia, particularly in patients with pre-existing cardiovascular disease. Rapid i.v. bolus injection of oxytocin at doses amounting to several IU may also lead to QTc prolongation. When Syntocinon is used for the management of the third stage of labour, multiple pregnancy must be excluded before the drug is injected.(MIMS)

Use in pregnancy. (Category A) Use of oxytocin has contributed significantly to the safety of parturition. However, there have been instances of idiosyncratic sensitivity of the uterus resulting in fetal anoxia.(MIMS)

NOTE: I have asked a question in a tutorial about Syntocinon's inability to cross the blood-brain barrier, while endogenous oxytocin, from the posterior lobe of the pituitary, does.  This topic is not addressed in the MIMS information.  The tutor said she would check the specific pharmacokinetics of synthetic oxytocin.


Syntometrine® synthetic oxytocin/ergometrine maleate

... Syntometrine combines the rapid uterine action of oxytocin, a nonapeptide hormone released by the posterior lobe of the pituitary, with the sustained uterotonic effect of ergometrine [an ergot alkaloid].

Following intramuscular administration, the latent period for the occurrence of the uterine response is considerably shorter with Syntometrine (about 2 1/2 minutes) than with ergometrine given alone (about 7 minutes), whereas the uterotonic effect of Syntometrine lasts for several hours, compared with only 1/2 to 1 hour when oxytocin is given alone. These properties make Syntometrine intramuscular suitable for the active management of the third stage of labour (see Dosage and Administration) and for the prevention or treatment of postpartum haemorrhage, particularly in situations where for any reason the intravenous administration of a uterotonic agent is impracticable. ...

Indications: Active management of the third stage of labour. Prevention and treatment of postpartum haemorrhage associated with uterine atony.

Contraindications: Hypersensitivity to oxytocin, ergometrine or to any of the components in the formulation. Pregnancy, ... Severe hypertension, pre-eclampsia or eclampsia. Severe cardiac disorders. Severe hepatic or renal impairment. Occlusive vascular disease. Sepsis.

Syntometrine has the potential to cause serious adverse drug reactions in breastfed newborns/ infants. Postpartum women receiving Syntometrine should avoid breastfeeding for at least 12 hours after the administration. Milk secreted during this period should be expressed and discarded. (MIMS)

NOTE: I have highlighted this paragraph in red, because I need to follow up on it.  I have never heard this information before, despite many years of working and using it in hospitals, as well as private practice.

Misoprostol is a synthetic prostaglandin E₁ analogue.is used in tablet form, given either orally, PR or PV.  Its use has been promoted for use in resource-poor settings - see FIGO initiative. 
I will not go into the pharmacology of this drug here, as I do not use it.  As with Syntometrine above, it comes with a warning about breast feeding:

Use in lactation. Misoprostol is rapidly metabolised in the mother to misoprostol acid, which is biologically active and is excreted in breast milk. Misoprostol should not be administered to breastfeeding mothers because the excretion of misoprostol acid could cause undesirable effects such as diarrhoea in breastfeeding infants.  (MIMS)

COMMENT:
This study has given me information which confirms my commitment to protecting, promoting and supporting unmedicated, physiological birth, except in clinical situations where there is a valid reason to intervene.  The benefit of synthetic oxytocic treatment in preventing excessive blood loss after birth is undeniable.  My reluctance to use these drugs routinely rather than as indicated is related to the majority of women for whom the treatment is not required, and who are thereby exposed to unnecessary medication with attendant risks.

I am also concerned about the extent of possible adverse effects in newborn babies, particularly any sick babies who may need to receive drug treatments, and who may experience adverse drug reactions to syntometrine in mother's milk.  

Thankyou for your comments

Journal: back to pharmacology

The last two weeks were the mid-term break for the university, and I was happy to take a break from study.  However, it wasn't a restful time for me, as several babies needed to make their entry into this world of ours, and they all needed me to be on the job through the night.  The early postnatal days are very demanding for the new mother, even after an uncomplicated birth, and the midwife needs to stay focused as we watch and support and at times guide.

We are now in Week 9 of the pharmacology course.  The focus is on writing prescriptions, and working on the second case study.

Today I have listened to the recording of an online tutorial of a session that one of the tutors has put up for students to access.  This is the first 'live' opportunity that any of the students have had to interact with the faculty.  Unfortunately it was attended by only 3 students, who were able to put questions and discussion.

The tutor gave information about the course expectations for the assignments.  I found the tutor's comments useful - would have preferred having this prior to submission of the first case study. The tutor stressed the importance of referencing scholarly articles, and going into depth about the pharmacology of the medications that are being discussed. This is the field that I would like more teaching on. I have read the articles, but find there is a lot of new knowledge to acquire, and I think it's a good learning strategy to hear and discuss a topic as well as to read about it.

For example, when considering the pharmacology of metoclopramide, used to treat nausea, we need to discuss the general pharmacokinetic and pharmacodynamic actions of the drug, together with the changes that occur as a result of pregnancy.  In addition to the physiological changes in a pregnant woman's digestive system, metoclopramide has an effect on the dopamine receptors in the GI tract, inhibiting some receptors, and activating cholinergic effects leading to increased motility of the GI tract, in addition to the effect of metoclopramide on the central nervous system.  Reference to scholarly papers is needed for each point made.

Much of this language is new to me, and to the midwifery profession as I know it.  I recognise the importance of a strong foundation when establishing a new body of knowledge.  I have written to the tutor requesting more opportunities for live teaching as well as discussion, so that I can hear as well as read and discuss these aspects of the course. 


Thankyou for your comments

Journal: writing prescriptions

Thismorning I have gone through the process of online submission of the first Case Study, which I wrote about in my most recent posting.  I found that I needed to restrict myself, as the word count was 2000-3000 words.  The additional material that I decided needed to be cut from the case study has mostly been pasted into my portfolio.

Today's task is to learn how to write prescriptions.  The list of medicines that are given for students to practice includes some drugs that I carry at present (such as lignocaine for perineal repair, and syntocinon to treat postpartum haemorrhage, and paediatric vitamin K), as well as narcotics oxycodone and panadeine forte, that I would seek to avoid. Antibiotics such as Amoxil and flucloxacillin may occasionally be useful.

My response to this assignment is complex, on several different levels.  While I am happy to upskill and have authorisation to prescribe medicines that are within my scope of practice, I feel conflicted as I am concerned that many midwives will prescribe just because they can.

One restriction that independent midwives have lived and worked under for as long as I can remember is that we have very little reliance on drugs.  Antibiotics, such as penicillin, are prescribed in many hospitals for any labouring woman who has tested positive to group B streptococcus (GBS).  In my practice, I do not swab for GBS, and I do not use antibiotics as a prophylaxis.  This is a safe practice, as long as there is no artificial rupture of the membranes, and as long as there are no internal examinations in early labour with ruptured membranes.  This practice is also safe because there is the stated intention to treat with antibiotics if symptoms of infection arise, particularly an unstable maternal temperature, with fetal tachycardia.

While every care plan focuses on avoidance of harm from the potentially catastrophic GBS infection, the plan to treat prophylactically is not without risk.  The use of antibiotics can lead to adverse effects in mother and baby, and long term morbidity. 

As an elder of the midwifery profession, I do not expect that my practice will change much, even when I have the right to prescribe from whatever formulary is available to midwives.  The PBS list is different from the NMBA list, which is different from the Victorian government's list (which has not yet been approved). 

I do hope younger midwives who move up in the ranks will hold to the basic knowledge of working in harmony with healthy natural processes in normal birth.  The principles of promoting, protecting, and supporting normal physiological processes are in the interests of mothers and babies, and are at the core of normal midwifery practice.

Thankyou for your comments