Labour (Drugs in Labour; Pain Relief; Instrumental delivery) Flashcards
Describe the MoA of oxytocin [2]
Oxytocin stimulates the ripening of the cervix and contractions of the uterus during labour and delivery. It also plays a role in lactation during breastfeeding.
Syntocinon is a brand name for oxytocin produced by one drug company.
When is oxytocin indicated? [4]
- Induce labour
- Progress labour
- Improve the frequency and strength of uterine contractions
- Prevent or treat postpartum haemorrhage
What is the MoA of ergometrine? [1]
When is it indicated? [2]
Ergometrine
* MoA: It stimulates smooth muscle contraction, both in the uterus and blood vessels.
* Indications: third stage of labour and to treat post-partum haemorrhage
Name three side effects of ergometrine [3]
Which condition is it contra-indicated in? [1]
Due to the action on the smooth muscle in blood vessels and gastrointestinal tract, it can cause several side effects, including hypertension, diarrhoea, vomiting and angina.
- Therefore needs to be avoided in eclampsia, and used only with significant caution in patients with hypertension.
[] is a combination drug containing oxytocin (Syntocinon) and ergometrine. It can be used for prevention or treatment of postpartum haemorrhage.
Syntometrine is a combination drug containing oxytocin (Syntocinon) and ergometrine. It can be used for prevention or treatment of postpartum haemorrhage.
Dinoprostone
- MoA? [2]
One key prostaglandin to be aware of is dinoprostone, which is prostaglandin E2
- Prostaglandins act like local hormones, triggering specific effects in local tissues. Tissues throughout the entire body contain and respond to prostaglandins.
- They play a crucial role in menstruation and labour by stimulating contraction of the uterine muscles. They also have a role in ripening the cervix before delivery.
One key prostaglandin to be aware of is dinoprostone, which is prostaglandin E2. This is used for induction of labour, and can come in one of which three forms? [3]
Vaginal pessaries (Propess)
Vaginal tablets (Prostin tablets)
Vaginal gel (Prostin gel)
What is the MoA of misoprostol? [1]
When is it indicated? [3]
Misoprostol is a prostaglandin analogue, meaning it binds to prostaglandin receptors and activates them.
It is used as medical management in miscarriage, to help complete the miscarriage.
Misoprostol is used alongside mifepristone for abortions, and induction of labour after intrauterine fetal death.
Describe the MoA of mifepristone [1]
When is it indicated? [1]
Mifepristone is an anti-progestogen medication that blocks the action of progesterone, halting the pregnancy and ripening the cervix.
- It therefore enhances the effects of prostaglandins to stimulate contraction of the uterus
- Misoprostol is used alongside mifepristone for abortions, and induction of labour after intrauterine fetal death.
It is not used during pregnancy with a healthy living fetus.
When is nifedipine indicated? [2]
Reduce blood pressure in hypertension and pre-eclampsia
Tocolysis in premature labour, where it suppresses uterine activity and delays the onset of labour
What is the MoA of Terbutaline? [1]
When is it indicated? [1]
Terbutaline is a beta-2 agonist, similar to salbutamol - It acts on the smooth muscle of the uterus to suppress uterine contractions
- It is used for tocolysis in uterine hyperstimulation, notably when the uterine contractions become excessive during induction of labour.
What is the MoA of carboprost? [1]
When is it indicated? [1]
Carboprost is a synthetic prostaglandin analogue, meaning it binds to prostaglandin receptors. It stimulates uterine contraction
It is given as a deep intramuscular injection in postpartum haemorrhage, where ergometrine and oxytocin have been inadequate
Which antifibrinolytic is used in prevention and treatment of PPH? [1]
Tranexamic Acid
Describe the pain relief that is available in labour [4]
1. Simple analgesia:
- Paracetamol
- Codeine
- NSAIDs are avoided
2. Gas and Air:
- 50% nitrous oxide and 50% oxygen
- used during contractions
3. Intramuscular Pethidine or Diamorphine:
- Opiods given IM
- help with anxiety and distress
- may cause drowsiness or nausea in the mother, and can cause respiratory depression in the neonate if given too close to birth
Patient Controlled Analgesia:
- intravenous remifentanil.
Which drug is used during PCA for labour? [1]
What are AEs? [2]
Which drugs are used to reverse these AEs? [2]
intravenous remifentanil
- need access to naloxone for respiratory depression, and atropine for bradycardia
Describe how an epidural is given [1]
Which drugs are used? [3]
- inserting a small tube (catheter) into the epidural space in the lower back (outside the dura mater, separate from the spinal cord and CSF)
- Local anaesthetic medications are infused through the catheter into the epidural space: including levobupivacaine or bupivacaine, usually mixed with fentanyl.
What are the main side effects of epidural? [2]
Increased probability of instrumental delivery
Women need urgent anaesthetic review if they develop significant motor weakness
- The catheter may be incorrectly sited in the subarachnoid space (within the spinal cord), rather than the epidural space.
A baby is born using instrumental delivery.
Which drug is given to reduce the risk of maternal infection? [1]
A single dose of co-amoxiclav is recommended after instrumental delivery to reduce the risk of maternal infection.
What are 4 key indications of performing instrumental delivery? [5]
Failure to progress
Fetal distress
Maternal exhaustion
Control of the head in various fetal positions
TOM TIP: It is worth remembering there is an increased risk of requiring an instrumental delivery when an epidural is in place for analgesia.
The key risks to remember to the baby are:
[] with ventouse
[] with forceps
The key risks to remember to the baby are:
Cephalohaematoma with ventouse ( blood that collects between a newborn’s scalp and skull)
Facial nerve palsy with forceps
Forceps delivery can leave bruises on the baby’s face. Rarely the baby can develop [].
What does this lead to? [1] .
Forceps delivery can leave bruises on the baby’s face. Rarely the baby can develop fat necrosis, leading to hardened lumps of fat on their cheeks. Fat necrosis resolves spontaneously over time.
Which nerve injuries to the mother can be caused by instrumental deliveries [2]
How would these present? [2]
Femoral nerve:
- compressed against the inguinal canal during a forceps delivery.
- Injury to this nerve causes weakness of knee extension, loss of the patella reflex and numbness of the anterior thigh and medial lower leg.
Obturator nerve
- forceps or by the head of baby
- Injury causes weakness of hip adduction and rotation, and numbness of the medial thigh.
