Analgesia in labour

Question 1

Where is pain carried in the first stage of labour?

Answer 1

in T10-L1 roots (pain caused by dilation of lower segment of uterus and cervix)

L2-S1 roots (pain caused by pressure on pelvic structures)

Question 2

Where is pain carried in the second stage of labour?

Answer 2

Pain of first stage continues

Pudendal nerves:
S2-4 roots (Pain caused by dilation and pressure on pelvic organs and pelvic floor structures)

Question 3

How might the pain in first stage of labour present?

Answer 3

poorly localised

visceral/colicky

Question 4

How might the pain in second stage of labour present?

Answer 4

somatic pain
sharp
well localised (to perineum)

Question 5

What factors might impact pain?

Answer 5

Position of baby

Size of baby

Pelvic anatomy

Strength of contraction

Complications – APH, uterine rupture, trauma

Previous experience & expectations

Other factors – anxiety, fear of pain, social factors, educational background, etc.

Question 6

What are some non-pharmacological methods of pain relief used in labour?

Answer 6

Support from birthing partner

Labouring in water

breathing and relaxation technique

massage

music

Question 7

What are some pharmacological analgesics that can be used in labour?

Answer 7

entonox

opioids: pethidine or diamorphine

non-opioids: paracetamol

epidural

Question 8

What are the benefits of entonox?

Answer 8

Significant analgesia

Non-invasive procedure

Quick onset/offset

Question 9

What are the side effects of entonox?

Answer 9

dizziness
nausea
amnesia

Question 10

What is a drawback of the entonox?

Answer 10

incomplete analgesia

Question 11

How can opioids be given in labour?

Answer 11

usually IM/IV

Question 12

What are some side effects of opioid analgesics?

Answer 12

sedation
nausea and vomiting
respiratory depression

Question 13

What regional anaesthesia can be given in labour?

Answer 13

lumbar epidural

spinal

combined spinal and epidural

caudal (not really done in UK)

para-cervical infiltration (not really done in UK)

Question 14

What takes place in a combined spinal epidural?

Answer 14

intrathecal injection and epidural catheter placement

Question 15

When might a combined spinal epidural be used in labour?

Answer 15

advanced labour
perineal pain
Re-siting epidural

Question 16

When are the complications associated with spinal epidural in labour?

Answer 16

Infection
Intrathecal migration of catheter

Immediate: failure
hypotension
LA toxicity
total spinal

Delayed:
PDPH (post dural puncture headache)
Infection
haematoma
neurological damage

Question 17

What are some ABSOLUTE contraindications for spinal epidural?

Answer 17

patient refusal
anti-coagulants & bleeding disorders (incl. if had recent dose of tinzaparin - need to wait)
local or severe systemic infection
anaphylaxis to LA

Question 18

What are some relative contra-indications for spinal epidural?

Answer 18

spinal surgery (only if simple, as many attempts = increased infection risk, which may lead to need of replacement of metal work etc.)

massive haemorrhage (this lowers BP, drugs may make this worse (sympathetic blockers))

Question 19

23 year old, 40 weeks pregnant – SROM, admitted to delivery room. Complains of mild tightening and lower abdo pain.

How would you approach this? What would you advise this woman?

Answer 19

Non-pharmacological

Pharmacological: start low - paracetamol
codeine
entonox

Question 20

30 year old, 38 weeks pregnant, hypertensive. Obstetric plan is to induce labour. 2 hours after Oxytocin infusion, she is beginning to get quite strong contractions….

What would you advise her?

Answer 20

Offer an epidural (may need to reduce oxytocin while you’re doing this)

This woman has three risk factors for C-section, therefore can advise her that this can stay in place for her C-section

Question 21

What is entonox?

Answer 21

Nitrous oxide
Oxygen

50:50 mixture

Question 22

25 year old woman, who has had a normal delivery. She had a good working epidural which came out an hour ago. She is complaining of weakness in both legs.

What could be causing this? What would you do?

Answer 22

wearing off of epidural
damage to spinal cord
haematoma

Involve anaesthetist
MRI of back

Question 23

When assessing your patient with an epidural you find them laying flat in bed complaining of feeling breathless.

What is your:
Differential diagnosis?

Answer 23

Total spinal
PE/amniotic embolism
anxiety
chest infection 
MI

Question 24

Why do opioids last longer when given IM

Answer 24

has to be absorbed, takes longer therefore lasts longer

Question 25

Why are spinal or epidural blocks generally done with patient sat up?

Answer 25

Prevent one-sided block

Question 26

16 year old, 40 weeks gestation, primiparous, low-risk. 5 cm cervix on examination, struggling to cope with pain.

What would you advise her?

Answer 26

Advise her to have epidural.

Struggling, pain will get worse and she is young so may have difficulties due to small hips etc.