Obstetrics Flashcards
What are prostaglandins and oxytocics used for in obstetrics? (3)
- Induce abortion
- Induce or augment labour
- Minimise blood loss from the placental site
Which drug can be used prior to the administration of prostaglandin during an abortion to sensitize the uterus?
Mifepristone
Sensitises the uterus to prostaglandin - the abortion occurs in shorter time and with a lower dose of prostaglandin
Name two prostaglandins that are licensed for the induction of abortion
Misoprostol
Gemeprost
What is the mode of administration of misoprostol for termination of pregnancy following mifepristone for gestation up to 49 days?
Oral
- 400 micrograms for 1 dose, given 24-48 hours after mifepristone
What drug needs to be given prior to misoprostol in termination of pregnancy?
Mifepristone
What is the mode of administration of misoprostol for termination of pregnancy following mifepristone for gestation 50-63 days? (3 options)
Vaginal OR Busccal OR Sublingual
What is the mode of administration of misoprostol for termination of pregnancy following mifepristone for gestation of 9-24 weeks?
Vaginal
What are the common side effects of misoprostol? (10)
- Chills
- Constipation
- Diarrhoea
- Dizziness
- Fever
- Flatulence
- GI discomfort
- Headache
- Nausea and vomiting
- Skin reactions
What advice about driving should patients taking misoprostol be told?
Increased risk of dizziness may have an effect on driving and performance of skilled tasks
Misoprostol is a synthetic (?) analogue that acts as a potent uterine stimulant
prostaglandin
Misoprostol is a synthetic prostaglandin analogue that acts as a potent (?) stimulant
uterine
Mifepristone, an (?), sensitises the myometrium to prostaglandin-induced contractions and ripens the cervix.
anti-progestogenic steroid
Mifepristone, an anti-progestogenic steroid, sensitises the (?) to prostaglandin-induced contractions and ripens the cervix.
myometrium
Mifepristone, an anti-progestogenic steroid, sensitises the myometrium to (?)-induced contractions and ripens the cervix.
prostaglandin
Mifepristone, an anti-progestogenic steroid, sensitises the myometrium to prostaglandin-induced contractions and ripens the (?).
cervix
What are the contra-indications to the use of mifepristone?
- Acute porphyrias
- Chronic adrenal failure
- Suspected ectopic pregnancy
- Uncontrolled severe asthma
What are the common side effects of mifepristone?
- Abdominal cramps
- Diarrhoea
- Infection
- Nausea and vomiting
- Pelvic inflammatory disease
- Uterine disorders
- Vaginal haemorrhage (sometimes severe)
What is the mode of administration for gemeprost (prostaglandin licensed for the medical induction of abortion in the second trimester)?
Vaginal
What are the indications for the use of gemeprost?
- Induction of abortion in the second trimester
2. Soften and dilate the cervix before surgical abortion in early pregnancy
Which trimester is gemeprost most commonly used to induce abortion?
Second trimester
What are the contra-indications for the use of gemeprost?
- Placenta praevia
- Unexplained vaginal bleeding
- Uterine scarring
What monitoring is essential in patients with who takes gemeprost in combination with mifepristone?
BP and pulse for 3 hours
Risk of profound hypotension
When gemeprost is used for induction of abortion during the second trimester, what needs to be monitored during treatment?
Coagulopathy
Dinoprostone is available as vaginal tablets and vaginal gels for the (?).
Induction of labour
(?) is licensed for induction or augmentation of labour, usually in conjunction with amniotomy; it is administered by slow intravenous infusion, using an infusion pump.
Oxytocin
What needs to be monitored carefully if oxytocin is used for induction or augmentation of labour?
Uterine activity
Fetal heart rate
DIC after parturition
What may result if oxytocin is used in large doses?
Excessive fluid retention
What two drugs can be given for induction of labour in women who have intrauterine fetal death (unlicensed use)?
Mifepristone and misoprostol
What are the common side effects of oxytocin? (3)
- Arrhythmias
- Headache
- Nausea and vomiting
Why must you avoid rapid IV injection of oxytocin?
May transiently reduce BP
Oxytocin is administered by slow IV infusion
Excessive doses of oxytocin can cause uterine hyperstimulation, what are the complications associated with uterine hyperstimulation? (7)
- Fetal distress
- Fetal asphyxia
- Fetal death
- Hypertonicity
- Tetanic contractions
- Soft-tissue damage
- Uterine rupture
What may occur in an oxytocin overdose? (2)
Placental abruption
Amniotic fluid embolism
What drug(s) is given as prophylaxis to prevent postpartum haemorrhage? (2 options)
Oxytocin (IM injection)
OR
Ergometrine with oxytocin (IM injection)
*carboprost and misoprostol are alternative options
Given on delivery of the anterior shoulder OR immediately after the baby is delivered
Ergometrine with oxytocin cannot be used as prophylaxis for postpartum haemorrhage in patients with which condition?
Hypertension
Oxytocin alone causes less nausea, vomiting and hypertension than when given with ergometrine maleate
Oxytocic drugs are used to treat potpartum haemorrhage caused by …
uterine atony
Treatment options include oxytocin, ergometrine maleate, or a combination of ergometrine with oxytocin. Carboprost and misoprostol [unlicensed] are alternative options.
Which drug is used for the medical management of ectopic pregnancy?
Methotrexate (systemic)
(?) drugs postpone premature labour and they are used with the aim of reducing harm to the child.
Tocolytic
Which drug is the first-line for tocolysis in women between 24-33 weeks of gestation who have intact membranes and are in suspected or diagnosed premature labour?
Nifedipine [unlicensed indication]
Alternative: atosiban
What are the contraindications for the use of nifedipine?
- Acute attacks of angina
- Cardiogenic shock
- Significant aortic stenosis
- Unstable angina
- Within 1 month of MI
What class of drug is nifedipine?
Calcium-channel blocker
Obstetrics: Used as a tocolytic to delay premature labour
What are the contraindications for the use of atosiban as a tocolytic? (9)
- Abnormal fetal heart rate
- Abruptio placenta
- Antepartum haemorrhage
- Severe pre-eclampsia
- Eclampsia
- Intra-uterine fetal death
- Intra-uterine infection
- Placenta praevia
- Premature rupture of membranes after 30 weeks’ gestation
Why are beta-2 agonists (salbutamol and terbutaline sulfate) NO LONGER USED for inhibiting uncomplicated premature labour?
Serious, sometimes fatal cardiovascular events in the mother and fetus
