Management of Labour and Delivery Flashcards

1
Q

Describe the 1st stage of labour.

A
  • Onset of labour, until the cervix of fully dilated.
    • Latent: painful contractions, where there is some cervical effacement and dilatation up to 4cm.
    • Established: painful contractions and progessive cervical dilatation from 4cm.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the 2nd stage of labour.

A
  • From full cervical dilation, until the baby / baby head is delivered.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the 3rd stage of labour.

A
  • From delivery of the baby, until delivery of the placenta and membranes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the observations made using a partogram.

A
  • Graphical display of intrapartum information.
  • Allows for assessment of the:
    • Power
      • Frequency and duration of contractions
      • Strength - remains subjective
    • Passenger
      • Foetal heart monitoring
      • Position / station / moulding / caput
    • Passage
      • Effacement and dilation of the cervix
  • Commence following accurate diagnosis of established labour
    • Progress in labour
    • Action lines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain the difference between induction and augmentation of labour.

A
  • Induction of labour:
    • The process of starting labour
  • Augmentation of labour:
    • Process of accelerating labour which is already underway:
      • Pre-Labour rupture of membranes
      • Delay in 1st / 2nd stage of labour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the indications for induction or augmentation of labour?

A
  • Prolonged pregnancy
    • In 5-10% of women pregnancies continue beyond 42 weeks.
    • Risk of perinatal death.
  • Maternal DM
  • Twin pregnancy
  • Pre-term rupture of membranes
  • Foetal growth restriction / placental insufficiency
  • Hypertensive disorders
  • Maternal medical disorders (renal /cardiac)
  • Maternal age
  • Reduced foetal movements
  • Maternal request
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the pharmacological methods of induction of labour?

A
  • Prostaglandins (PGE2)
    • Promote cervical ripening and stimulate uterine contraction.
    • Vaginal route has fewest side effects.
      • Gel / tablet / sustained release pessary.
    • Greater risk of hyperstimulation.
  • Syntocinon
    • ‘Synthetic’ oxytocin
    • Stimulates uterine contraction
    • Only used following amniotomy
    • IV infusion / dose titration to achieve contractions 4:10
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the mechanical methods of inducing / augmenting labour?

A
  • Membrane sweep
    • May double incidence of onset of spontaneous labour if carried out after 40/40.
  • Amniotomy (ARM - artificial rupture of membranes)
    • Favourable cervix
    • Also used to augment labour
    • Allows assessment of the colour of liquor
    • More likely to require oxytocin augmentation
    • Head should be engaged or there is risk of cord prolapse.
  • Other
    • Balloon
    • Laminaria tents
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the cervical scoring system and how this determines which procedure should be carried out.

A
  • Assess favourability of the cervix.
    • Score <8 = unfavourable cervix → ripen with PG.
    • Score 8+ = favourable cervix → proceed with amniotomy.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the complications of induction and augmentation of labour?

A
  • Uterine hyperstimulation (1-5%)
    • Foetal distress
    • Remove stimulus / role of tocolysis
  • Labour experience
  • Increased obstetric intervention
    • Epidural
    • Assisted vaginal delivery
  • No increased risk of C-section
  • Uterine rupture
    • Caution in the presence of previous uterine surgery, especially with prostaglandins
  • Failure / repeat courses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the methods of pain relief used during delivery?

A
  • Non-pharmcological
  • Pharmacological:
    • Inhaled
    • Opioid
    • Regional
  • Delivery
    • Local anaesthetic
      • Perineal
      • Pudendal
    • Regional
    • GA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

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

A
  • Maternal support
    • 1:1 care in labour
      • Requires less analgesia, higher SVD rate, better experience in labour.
    • Birthing pools
      • Reduce the need for regional anaesthesia
      • Caution if the mother has had opioid analgesics
    • Breathing and relaxation techniques / accupuncture / hypnosis / massage / aromatherapy / TENS.
      • Limited evidence to support use.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the use of Entonox in labour.

A
  • 50:50 mixture of O2 and nitrous oxide
  • Commonly used
  • Not a potent analgesic
  • Generally very safe to use
  • Adverse effect
    • Nausea
    • Vomiting
    • Drowsiness
    • Light-headedness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the use of opioid analgesics in labour.

A
  • Diamorphine 5-10mg
  • Tend to have a limited effect during labour
  • Adverse effects:
    • Maternal
      • Nausea and vomiting (administer with anti-emetic)
      • Drowsiness
    • Neonatal
      • Drowsiness / respiratory depression (ideally do not administer within 3-4 hours of delivery)
  • Continuous IV infusion
    • Remifentanil
    • Short acting
    • PCA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the factors involved in prescribing epidural anaesthesia during labour?

A
  • Regional anaesthesia = epidural.
  • More effective than parenteral opioids.
  • Prolonged second stage
    • Increases AVD
    • No increase in lower uterine segment C-section
    • Increase in malabsorption
  • Top-up
    • Obstetric intervention
  • Side effects:
    • Hypotension
    • Pyrexia / pruritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the factors involved in prescribing spinal anaesthesia during labour?

A
  • Regional anaesthesia = spinal.
  • Predominantly used for obstetric intervention
    • Denser block than epidural
  • Single shot injection, lasts 2-4 hours
  • Side effects:
    • Hypotension
    • Pyrexia / pruritis
    • High block
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the risks associated with GA during labour?

A
  • Higher risks in the pregnant population compared to the non-pregnant population.
  • Tissue oedema
  • Reduced gastro-oesophageal tone
  • Increased intra-abdominal pressure
  • Delayed gastric emptying
  • Increased gastric acidity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the aim of intrapartum foetal monitoring?

A
  • The ultimate aim of intrapartum foetal monitoring is the prevention of death and morbidity due to hypoxia.
    • Hypoxaemia / hypoxia cause changes in the foetal heart rate pattern.
  • Changes in the foetal heart pattern during labour are very common, but significant foetal hypoxia is relatively rare.
    • C-section rates tend to rise by ~30% with the use of ‘routine’ monitoring, due to over-diagnosis of foetal distress.
    • Can restrict mobility in labour.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What factors affect the foetal heart rate?

A
  • The heart has an intrinsic rate.
  • Nerve supply
    • Rate is reduced by the vagus nerve (parasympathetic)
    • Rate is increased by the sympathetic supply
  • Circulating catecholamines
    • Adrenal
  • CNS activity
  • Changes in foetal blood pressure
  • Changes in foetal blood gas levels (O2, CO2, pH)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the use of intermittent auscultation in labour.

A
  • ‘Low risk’ women in established labour.
  • Doppler USS
  • Performed immediately after a contraction for at least 1 minute, at least every 15 minutes.
  • Recorded as a single rate, noting accelerations or decelerations if heard.
  • Palpate maternal pulse.
  • Act upon any changes:
    • Rising baseline rate
    • Decelerations
    • Assess the patient (position, hydration, contraction (frequency / tone), maternal observations).
    • Increase frequency of auscultation.
    • Continuous CTG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the indications for continuous CTG monitoring in labour?

A
  • Maternal tachycardia
  • Maternal pyrexia
  • Suspected chorioamnionitis or sepsis
  • Presence of significant meconium
  • Fresh vaginal bleeding
  • Hypertension / proteinuria
  • Confirmed delay in labour (1st or 2nd stage)
  • Hypertonus or tachysystole
  • Oxytocin use
  • Reported pain outwith the normal
  • Preterm
  • Multiple pregnancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the protocol for interpreting a CTG.

A
  • Dr - determine risk
  • C - contractions
  • Bra - baseline rate
  • V - variability
  • Accelerations
  • Decelerations
  • Overall assessment
23
Q

What is foetal capillary blood sampling used to assess?

A
  • Foetal scalp capillary sample to assess acidaemia
    • pH >7.25 - reassuring
    • pH <7.2 - nonreassuring / immediate delivery
24
Q

Why is flexion of the foetal neck important during delivery?

A
25
Q

Describe steps 1 and 2 of a normal vaginal delivery.

A
  • Head in pelvic brim in left or right occipitolateral position.
  • Neck flexes so that the presenting diameter is suboccipitobregmatic.
26
Q

Describe steps 3 and 4 of a normal vaginal delivery.

A
  • Head delivers by extension.
  • Descent continues and shoulders rotate into the anteroposterior diameter of the pelvis.
27
Q

Describe steps 5, 6 and 7 of a normal vaginal delivery.

A
  • Head restitutes.
  • Anterior shoulder delivered by lateral flexion from downward pressure on the baby’s head.
  • Posterior shoulder delivered by lateral flexion upwards.
28
Q

What is malpresentation?

A
  • Malpresentation is the term used to describe any non-vertex presentation.
    • Face: ~1:500
    • Brow: ~1:700-1500
    • Breech: ~3-4% at term
    • Transvere lie and oblique lie: <1% at term
29
Q

Describe face presentation.

A
  • Hyper-extension of the head.
  • Associated with prematurity, tumours of the neck, fetal macrosomia, anencephaly.
  • Face is usually very swollen.
  • Position in relation to the chin (mento). If mento-anterior, can deliver vaginally with flexion of the neck.
30
Q

Describe brow presentation.

A
  • Presenting diameter is mento-vertical (14cm).
  • Less likely to be delivered vaginally, unless head flexes during labour to become vertex presentation.
31
Q

Describe breech presentation.

A
  • Associated with multiple pregnancy, bicornate uterus, fibroids, placenta praevia, polyhydramnios, oligohydramnios.
  • 65% - frank (extended) breech.
  • 35% - flexed or footing breech.
32
Q

Describe transverse lie and oblique lie.

A
  • More common in multiparous women, polyhydramnios, preterm labour, fibroids, uterine anomalies, placenta praevia.
  • Risk of cord prolapse / limb prolapse - role of hospital confinement at term.
33
Q

What are the indications for assisted vaginal delivery?

A
  • Maternal
    • Failure to progress in active second stage of labour.
      • Prim 2-3 hours
      • Parous - 1-2 hours
    • Maternal exhaustion
  • Foetal
    • Suspected foetal compromise in second stage of labour.
    • Pathological CTG
    • Abnormal FBS
  • Prophylactic shortening of second stage.
    • Hypertensive crisis
    • Cardiac disease
    • Maternal cerebrovascular disease
34
Q

What are the criteria to carry out assisted vaginal delivery?

A
  • Consent / analgesia / empty bladder.
  • Abdominal palpation: head engaged 0/5 palpable.
  • Vaginal examination: cervix fully dilated, membranes ruptured, presenting part at / below ischial spines.
  • Position of the foetal head.
35
Q

What are the serious maternal risks associated with assisted vaginal delivery?

A
  • 3rd and 4th degree perineal tear: 1-4 in 100 with vacuum-assisted delivery (common) and 8-12 in 100 with forceps delivery (very common).
  • Extensive or significant vaginal / vulval tear: 1 in 10 with vacuum and 1 in 5 with forceps.
36
Q

What are the serious foetal risks associated with assisted vaginal delivery?

A
  • Subgaleal haematoma: 3-6 in 1000 (uncommon).
  • Intracranial haemorrhage: 5-15 in 10,000 (uncommon).
  • Facial nerve palsy (rare).
37
Q

What are the common maternal risks associated with assisted vaginal delivery?

A
  • PPH: 1-4 in 10 (very common).
  • Vaginal tear / abrasion (very common).
  • Anal sphincter dysfunction / voiding dysfunction.
38
Q

What are the common foetal risks associated with assisted vaginal delivery?

A
  • Forceps marks on face (very common).
  • Chignon / cup marking on the scalp (practially all cases of vacuum-assisted delivery).
  • Cephalhaematoma: 1-12 in 100 (common).
  • Facial or scalp lacerations: 1 in 10 (common).
  • Neonatal jaundice / hyperbilirubinaemia: 5-15 in 100 (common).
  • Retinal haemorrhage: 17-38 in 100 (very common).
39
Q

What is shoulder dystocia?

A
  • Impaction of the foetal anterior shoulder behind the maternal symphysis pubis.
  • In practical terms:
    • Difficulty in delivering the shoulders, requiring additional manouvres beyond moderate axial traction.
  • Incidence 0.2%:
    • 0.5% if foetal weight >3.5kg
    • 10% if foetal weight >4.5kg
40
Q

What are the risk factors for shoulder dystocia?

A
  • In >50% cases - no risk factors
  • Macrosomia
  • DM
  • Postdates
  • Obesity
  • High parity
  • Prolonged 1st / 2nd stage
  • AVD
41
Q

What are the consequences of shoulder dystocia?

A
  • Hypoxia
    • Trapped umbilical cord
    • pH drop ~0.04 / min
    • 5-7 mins = significant foetal morbidity / mortality
  • Nerve damage
    • Excessive downward traction
      • C5-T1
      • Erb (C5-C6)
42
Q

What is the protocol for managing shoulder dystocia?

A
  • H - Call for help
  • E - Episiotomy
  • L - Legs to McRoberts
  • P - Pressure
  • E - Enter manouvres
  • R - Remove posterior arm
  • R - Roll over
43
Q

What is a 1st degree perineal tear?

A

Injury to the perineal skin and / or vaginal mucosa.

44
Q

What is a 2nd degree perineal tear?

A

Injury to perineum involving perineal muscles but not involving the anal sphincter.

45
Q

What is a 3rd degree perineal tear?

A
  • Injury to the perineum involving the anal sphincter complex:
    • Grade 3a - <50% of external anal sphincter (EAS) thickness torn.
    • Grade 3b - >50% of EAS thickness torn.
    • Grade 3c - Both EAS and internal anal sphincter (IAS) torn.
46
Q

What is a 4th degree perineal tear?

A

Injury to the perineum involving the anal sphincter complex (EAS and IAS) and anorectal mucosa.

47
Q

Describe episiotomy.

A
  • Not routinely performed.
  • No clear evidence that they reduce 3rd / 4th degree tears.
  • Indications:
    • Large tear anticipated
    • Suspected foetal compromise
    • AVD
    • Shoulder dystocia
    • ‘Rigid’ perineum
  • Anaesthesia
  • Mediolateral
48
Q

What are the risk factors and prognosis for obstetric anal sphincter injury?

A
  • Risk factors
    • Primigravida
    • Foetal weight >4kg
    • Shoulder dystocia
    • AVD
    • Asian ethnicity
    • Shortened perineum
  • Prognosis
    • 60-80% women asymptomatic after 12 months following identification and repair.
    • Physiotherapy
    • Future mode of delivery
49
Q

Describe the 4 categories of Caesarean Section.

A
  1. Requiring immediate delivery. Immediate threat to the life of woman or foetus.
  2. Requiring urgent delivery. Maternal or foetal compromise which is not immediately lfe-threatening.
  3. Requiring early delivery. No maternal or foetal compromise.
  4. Elective. At a time to suit the woman and obstetric team.
50
Q

What are the indications for caesarean section?

A
  • Breech / malpresentation
  • Previous CS
  • Severe growth restriction / placental insufficiency
  • Placenta praevia
  • Suspected foetal compromise
  • Failure to progress in labour
  • Unsuccessful triad of assisted vaginal delivery
  • Maternal request
  • Past obstetric history (trauma / dystocia)
  • Twins
51
Q

What are the surgical considerations when performing CS?

A
  • Incision
    • Low transverse incision / Pfannestial / Joel Cohen
  • Abdominal wall anatomy
  • Care of the bladder
  • Uterine incision
  • Delivery of the foetus
  • Delivery of the placenta and membranes
  • Repair of the uterus
    • Control of haemostasis
  • Repair of abdominal wall & closure
52
Q

What are the serious risks associated with CS?

A
  • Maternal
    • Emergency hysterectomy (uncommon).
    • Need for further surgery at a later date, including curettage (uncommon).
    • Admission to ICU (highly dependent on reason for CS) (uncommon).
    • Thromboembolic disease (rare).
    • Bladder injury (rare).
    • Ureteric injury (rare).
    • Death (very rare).
  • Future pregnancies
    • Increased risk of uterine rupture during subsequent pregnancies / deliveries (uncommon).
    • Increased risk of antepartum stillbirth (uncommon).
    • Increased risk in subsequent pregnancies of placenta praevia and placenta accreta (uncommon).
53
Q

What are the common risks associated with CS?

A
  • Maternal
    • Persistent wound and abdominal discomfort in the first few months after surgery (common).
    • Increased risks of repeat CS when vaginal delivery attempted in subsequent pregnancies (very common).
    • Readmission to hospital (common).
    • Haemorrhage (uncommon).
    • Infection (common).
  • Foetal
    • Lacerations (common).