Non-Hormonal Therapy in Obstetrics and Gynaecology Flashcards
Name the 4 clear indications for antihypertensive therapy in pregnancy
1) Persistent BP over 160/100
2) Acute severe hypertension
3) Fulminating PET
4) Eclampsia
Note = Treatment over 140/90 is debatable, most obstetricians pragmatically treating over 150/100
Talk to me about labetalol, class action, is it safe, what are the side effects
Labetalol = Considered safe and used extensively in human pregnancy. Generally it is considered to be first line treatment
Class = non specific alpha and beta blockers
Indications = Can be used for HTN, but also can be used for acute hypertension as IV.
Side effects
1) May cause IUGR with prolonged used = even after controlling for BP control
2) Neonatal hypoglycaemia + Bradycardia = Rare occurences
Talk to me about methyldopa, its class action, is it safe, and its side effects
Methyldopa = Considered safe in pregnancy and also extensively used in human pregnancy. It is add on treatment after labetalol, but can also be used first line (asthmatics)
Action = Post synaptic a2 agonist. Im this way it actually reduces sym action
Side effects =
1) Rebound hypertension
2) depressed mood = With long term use
3) Flattened CTG variability
4) Autoimmune haemolytic anaemia = Rare
5) Raised prolactin
6) Hepatitis
Talked to me about nifedipine for hypertension in pregnancy, is it safe, when is it used, class action, side effects.
Nifedipine = Not licensed in pregnancy, but commonly used as second line treatment. Use the MR version as otherwise can cause acute hypotension.
Action = Ca blocker. has preferential effect on vessels as vasodilator rather then heart.
Indication = Can also be used for acute hypertension
Labour = It also may inhibit premature labour (unlicensed used) Has been used as a tocolytic agent.
Side effects
1) acute hypotension, if give sublinguially
2) Peripheral oedema
3) Headache + Flushin
Talk to me about the use of hydralazine for hypertension in pregnancy. When is it used, how does it act, and what are the side effects
IV hydralazine = Used for acute hypertension. Give slowly over a minimum of 5 minutes, and can be repeated IV every 15 minutes
Action = Potent vasodilator
Metabolism = By acetylisation in liver.
Side effects
1) Acute hypotension = If given to fast or too often
2) Idiosyncratic adverse event = Of a lupus like syndrome = Occurs in people who are slow acetylators in liver.
Talk to me about the use of magnesium sulphate in pregnancy. How it acts, when it is used, and the side effects
MgSO4 = Best prevent and treatment for fits in severe PET or eclampsia.
MAGPIE trial = MgSO4 halved the risk of eclampsia and reduced maternal deaths.
Action = It is membrane stabaliser.
Monitoring = Only requires monitoring if the patient is oliguric
Side effects =
1) Hyporeflexia
2) Resp depression
3) Cardio-resp arrest
Name the 2 classes of antihypertensives that cannot be used in pregnancy and the reasons why including teratogenic effects
ACE-Is = Cannot use
Congenital malformations = Esp CVS
Skull defects
Oligohydramnios + Impaired renal function = Less AF as kidneys work less
Thiazide diuretics = Try not to use
Causes neonatal thrombocytopaenia with bendrometahfluzide
Give 3 indications for the use of a tocolytic medication
1) To abolish unwanted contractions = Preterm labour
2) Acute hyperstimulation
3) External cephalic version
What are the 2 uses for a tocolytic agent when used for pre term labour
1) To achieve 24 hr steroid latency in gestations less then 34 weeks.
2) Where in utero transfer to a neonatal centre is neccesary.
What are 5 main drugs used as tocolytics for preterm labour. Which one is first line, and what are the side effects.
First line = Nifedipine as recommended by NICE. Works as well as the other drugs below with better side effect profile
Second line = Atosiban = This works as an oxytocin antagonist.
Side effects = Naseua, tachycardia, hypotension
Beta-sympathomimentics = Such as salbutamol, ritodrine, terbutaline. These used to be used a lot, but now not so much because of side effects
Side effects = Tachycardia, hypotension, pulmonary oedema, hypokalaemia, hyperglycaemia. NICE says DO NOT USE
Mg SO4 = More used in the USA. Use for neuroprotection from 24-30 weeks gestation, and some evidence for 30-34 weeks.
GTN patches = No benefit over others really. But less side effects = Headache, hypotension.
Which tocolytic agents are used for ECV?
Terbutaline S/C = Can only be used in primigravidae women prior to ECV
Evidence = Shown to increased procedural success.
Which tocolytic agent is used in emergency tocolysis. When is it used, and how does it help
Terbutaline IV = This is a beta sympathomimentic, so side effects are these.
Indication = Used in uterine hyperstimultion which is normally brought on by oxytocin. Shown to improve foetal heart rate patterns and foetal pH
Talk to me about paracetamol in pregnancy
Absolutely fine for both pyrexia + analgesia
Use it first line
What are the indications for taking aspirin in pregnancy. When is it taken. When should it be stopped
Low dose aspirin 75mg = Used to prevent pre-eclampsia and IUGR. Should not be used liberally in low risk women, only high risk.
Indication = For high risk women to take from 12-36 weeks gestation
High risk:
1) Hypertensive disease in prev pregnancy
2) CKD
3) Autoimmune diseases like SLE or antiphospholipid syndrome
4) Type 1 or 2 DM
5) Chronic hypertension = BIG ONE
Stop taking = 2-3 weeks prior to pregnancy as theoretical risk of neonatal haemorrhage.
Can NSAIDs be used in pregnancy, what are there main side effects.
They should NEVER be used as analgesic. They have been used (like aspirin) to prevent preterm labour.
Side effects
1) Possible increase risk in miscarraige
2) Foetal renal impairment and oligohydrmanios (makes sense)
3) Increased risk of premature closure of ductus arteriosis.
4) Potential small increase risk of NEC
5) Cause maternal UGI symptoms and renal impairment.
