Intrapartum Care: Umbilical Cord Prolapse, Shoulder Dystocia & Instrumental Delivery

Question 1

What is cord prolapse?

Answer 1

When the umbilical cord descends below the presenting part of the fetus and through the cervix into the vagina, after rupture of the fetal membranes.

Question 2

If left untreated, what can umbilical prolapse lead to?

Answer 2

Compression of the cord or cord spasm –> fetal hypoxia.

Question 3

What is the most significant risk factor for cord prolapse?

Answer 3

When the fetus is in an abnormal lie after 37 weeks gestation (i.e. unstable, transverse or oblique).

Question 4

How does the fetus being in an abnormal lie increase the risk of cord prolapse?

Answer 4

Being in an abnormal lie provides space for the cord to prolapse below the presenting part.

In a cephalic lie (normal), the head typically descends into the pelvis, without room for the cord to descend.

Question 5

Risk factors for cord prolapse?

Answer 5

• abnormal presentations e.g. Breech, transverse lie
• prematurity
• multiparity
• polyhydramnios
• twin pregnancy
• cephalopelvic disproportion

Question 6

When do approx 50% of cord prolapses occur?

Answer 6

At artificial rupture of the membranes.

Question 7

When should cord prolapse be suspected?

Answer 7

Where there are signs of fetal distress on the CTG.

Question 8

How is a diagnosis of cord prolapse made?

Answer 8

Signs of fetal distress on the CTG + cord palpable on vaginal exam.

Question 9

Management of cord prolapse?

Answer 9

Obstetric emergency!

1) The presenting part of the fetus may be pushed back into the uterus to avoid compression

2) If the cord is past the level of the introitus, there should be minimal handling and it should be kept warm and moist to avoid vasospasm

3) C section usually indicated

Question 10

In cord prolapse, if the cord is past the level of the introitus, how can vasopasm be avoided?

Answer 10

1) minimal handling of cord

2) keep cord warm and moist

Question 11

In cord prolapse, what position should the woman be in until preparations for an immediate caesarian section have been carried out?

Answer 11

Patient is asked to go on ‘all fours’.

The left left lateral position (with a pillow under the hip) is an alternative.

Question 12

What drug can be used in cord prolapse to reduce uterine contractions whilst waiting for delivery by caesarean section?

Answer 12

Tocolytics e.g. nifedipine, terbutaline

Question 13

Why can retrofilling the bladder with 500-700ml of saline be helpful in cord prolapse?

Answer 13

As it gently elevates the presenting part.

Question 14

1st line of delivery in cord prolapse?

Answer 14

Caesarian section

Question 15

Why is patient asked to go on all fours in cord prolapse?

Answer 15

This position uses gravity to draw the fetus away from the pelvis and reduce compression on the cord.

Question 16

What is shoulder dystocia?

Answer 16

A complication of vaginal cephalic delivery when the anterior fetal shoulder becomes stuck on the maternal pubic symphysis, resulting in delayed birth of the baby’s body.

Obstetric emergency!

Question 17

What is the major complications of shoulder dystocia?

Answer 17

1) Shoulder compression may cause the umbilical cord to become compressed between the baby’s body and the mother’s pelvis.

2) The baby’s neck may be compressed at an angle that limits blood flow.

3) Hypoxia brain injury due to interruption of the oxygen supply.

Question 18

Cause of shoulder dystocia?

Answer 18

Shoulder dystocia usually occurs unexpectedly during childbirth and is not predictable.

Question 19

What are some pre-labour risk factors for shoulder dystocia?

Answer 19

1) previous shoulder dystocia

2) macrosomia >4.5kg

3) diabetes mellitus

4) maternal BMI >30

5) induction of labour

Question 20

What are some intrapartum risk factors for shoulder dystocia?

Answer 20

1) prolonged 1st stage of labour

2) 2ary arrest: no change in cervical dilation over time.

3) prolonged 2nd stage of labour

4) oxytocin augmentation

5) assisted vaginal delivery

Question 21

How does a baby’s birth weight affect risk of shoulder dystocia?

Answer 21

Shoulder dystocia is more likely in babies with higher birth weights, but it should be noted that there is no difficulty delivering the shoulders in most babies over 4.5kg.

Question 22

What is the biggest maternal risk factor for shoulder dystocia?

Answer 22

Diabetes: the risk is significantly higher, even with a similar-sized baby.

Question 23

If a woman has pre-existing diabetes or develops diabetes in pregnancy, what will they be offered to reduce/eliminate risk of shoulder dystocia?

Answer 23

Early labour induction or planned caesarean.

Question 24

How does shoulder dystocia present?

Answer 24

1) Difficulty delivering the face and head.

2) Unable to deliver the anterior shoulder after the delivery of the head with the next contraction

3) May be failure of restitution: where the head remains face downwards (occipito-anterior) and does not turn sideways as expected after delivery of the head.

4) The turtle-neck sign: where the head is delivered but then retracts back into the vagina.

Question 25

What is the turtleneck sign?

Answer 25

The appearance and retraction of the baby’s head (like a turtle withdrawing into its shell), with a red, puffy face.

Question 26

Management of shoulder dystocia?

Answer 26

1) Call for help

2) Advise the mother to stop pushing

3) 1st line: McRoberts manoeuvres

Question 27

What is 1st line manoeuvre in shoulder dystocia?

Answer 27

McRoberts manoeuvres

Question 28

Why is the mother advised to stop pushing in shoulder dystocia?

Answer 28

As can worsen the fetal impaction.

Question 29

What is McRoberts manoeuvres?

Answer 29

1) Hyperflex & abduct maternal hips to widen the pelvic outlet i.e. bringing thighs towards abdomen (this alone has a success rate of about 90% which is even higher when combined with suprapubic pressure)

2) Suprapubic pressure applied behind the anterior shoulder to disimpact it from the maternal symphysis.

Question 30

2nd line manoeuvres in shoulder dystocia if McRoberts manoeuvres is unsuccessful?

Answer 30

1) Posterior arm: inserting the hand posteriorly to grasp the posterior fetal arm and deliver

2) Internal rotation (‘corkscrew’): simultaneously applying pressure in front of one shoulder and behind the other. The aim is to rotate the baby 180 degrees.

Question 31

What is an episiotomy?

Answer 31

An incision between the vagina and anus.

Question 32

How can an episiotomy be used in shoulder dystocia?

Answer 32

An episiotomy can allow more space to facilitate internal vaginal manoeuvres but will not relieve the bony obstruction of the shoulder.

Question 33

Why should you always avoid downwards traction on the fetal head in shoulder dystocia?

Answer 33

As this increases the risk of brachial plexus injury (a major cause of litigation in obstetrics).

Question 34

Post-delivery management in shoulder dystocia?

Answer 34

1) Active management of the third stage of labour is recommended due to the increased risk of post-partum haemorrhage

2) Shoulder dystocia can be a traumatic experience for the mother and birth partner, provide support and debrief the following delivery

3) A rectal examination should be performed to exclude a third- or fourth-degree tear

4) Paediatric review is recommended before discharge to assess for complications such as brachial plexus injury

Question 35

Is there risk of recurrence of shoulder dystocia in future pregnancies?

Answer 35

Yes - mothers should be informed of this risk and given options for subsequent deliveries.

Question 36

maternal complications of shoulder dystocia?

Answer 36

1) Third- or fourth-degree tears

2) Post-partum haemorrhage

3) Trauma/post-traumatic stress disorder

Question 37

Foetal complications of shoulder dystocia?

Answer 37

1) Brachial plexus injury (BPI)

2) Fractures: humerus or clavicle

3) Hypoxic brain injury.

Question 38

What % of babies who have shoulder dystocia will have a degree of brachial plexus injury.

What is the most common type of injury?

Answer 38

Erb’s palsy.

This is usually temporary, and movement will return within hours or days. Permanent damage is rare.

Question 39

What is a brachial plexus injury?

Answer 39

Stretching of the brachial nerve plexus in the neck.

Question 40

What is Erb’s palsy?

Answer 40

A paralysis of the arm caused by injury to the upper trunk C5-C6 of the brachial plexus.

Question 41

What is instrumental delivery/operative vaginal delivery (OVD)?

Answer 41

Instrumental delivery refers to a vagina delivery assisted by either a ventouse suction cup or forceps.

These tools are used to help deliver the baby’s head.

Question 42

What % of births in the UK are assisted by an instrumental delivery?

Answer 42

Around 10%

Question 43

What are the 2 main instruments used in operative deliveries?

Answer 43

1) ventouse

2) forceps

The choice is operator dependent, but forceps tend to have a lower risk of fetal complications, and a higher risk of maternal complications.

Question 44

Risk of fetal and maternal complicatiosn when using forceps vs ventouse in birth?

Answer 44

Forceps –> lower risk of fetal complications but a higher risk of maternal complications.

Ventouse –> higher risk of fetal complications but a lower risk of maternal complications.

Question 45

What is recommended after instrumental delivery to reduce the risk of maternal infection?

Answer 45

A single dose of co-amoxiclav

Question 46

What are some key indications to perform an instrumental delivery?

Answer 46

The decision to perform an instrumental delivery is based on the clinical judgement of the midwife or obstetrician.

1) failure to progress
2) fetal distress
3) maternal exhaustion
4) control of the head in various fetal positions

Question 47

How does an epidural affect chance of requiring an instrumental delivery?

Answer 47

There is an increased risk of requiring an instrumental delivery when an epidural is in place for analgesia.

Question 48

What is the ventouse?

Answer 48

An instrument that attaches a cup to the fetal head via a vacuum. The suction cup goes on the baby’s head, and the doctor or midwife applies careful traction to the cord to help pull the baby out of the vagina.

The most common are:

1) An electrical pump attached to a silastic cup.

2) A hand-held, disposable device commonly known as the “Kiwi”.

Question 49

When is ventouse comprised of an electrical pump attached to a silastic cup only suitable?

Answer 49

This is only suitable if the fetus is in an occipital-anterior position.

Question 50

What foetal positions can the ventouse comprised of a hand-held, disposable device commonly known as the “Kiwi” be used for?

Answer 50

This is an omni-cup – it can be used for all fetal positions, and rotational deliveries.

Question 51

To use the ventouse, where is the cup applied?

Answer 51

The cup is applied with its centre over the flexion point on the fetal skull (in the midline, 3cm anterior to the posterior fontanelle).

Question 52

Where is the flexion point on the foetal head?

Answer 52

In the midline, 6 cm posterior to the anterior fontanelle or 3 cm anterior to the posterior fontanelle.

Question 53

What is the main foetal complication of using a ventouse?

Answer 53

Cephalohaematoma: a collection of blood between the skull and the periosteum.

Question 54

How are forceps used in delivery?

Answer 54

They come as two pieces of curved metal that attach together, go either side of the baby’s head and grip the head in a way that allows the doctor or midwife to apply careful traction and pull the head from the vagina.

Question 55

What are 3 types of forceps?

Answer 55

1) Rhodes, Neville-Barnes or Simpsons – used for OA positions.

2) Wrigley’s – used at Caesarean section.

3) Kielland’s – used for rotational deliveries.

Question 56

What is the OA position?

Answer 56

The best position for the baby to be in to pass through the pelvis: with head down and the body facing towards the mothers back.

This is known as occiput anterior (OA).

Question 57

What is the main foetal complication of using forceps in delivert?

Answer 57

Facial nerve palsy, with facial paralysis on one side.

Question 58

Foetal complications of forceps delivery?

Answer 58

1) Facial nerve palsy

2) Bruising on baby’s face

3) Baby can develop fat necrosis, leading to hardened lumps of fat on their cheeks (this resolves spontaneously over time).

Question 59

What should the decision to perform an operative vaginal delivery be based on?

Answer 59

The entire clinical scenario in the 2nd stage of labour.

There are two questions that should be asked:

1) Is there a valid clinical indication to intervene?

2) Is the patient a suitable case for an instrumental delivery?

Question 60

What defines inadequate progress in nulliparous women?

Answer 60

As a general rule, expect delivery after two hours of active pushing.

If no urge to push is felt at the diagnosis of second stage (common with regional anaesthesia), an hour can be allowed for fetal descent before starting active pushing.

Question 61

What defines inadequate progress in multiparous women?

Answer 61

Expect delivery with one hour of active pushing, with an hour for descent if needed prior to active pushing.

Question 62

What are some foetal indications for performing an instrumental delivery?

Answer 62

1) Suspected fetal compromise in the second stage of labour, usually diagnosed by:
- CTG monitoring
- Abnormal fetal blood sample

2) Clinical concerns e.g significant antepartum haemorrhage

Question 63

What are some absolute contraindications to instrumental delivery?

Answer 63

1) Unengaged fetal head in singleton pregnancies.

2) Incompletely dilated cervix in singleton pregnancies.

3) True cephalo-pelvic disproportion (where the fetal head is too large to pass through the maternal pelvis).

4) Breech and face presentations, and most brow presentations.

5) Preterm gestation (<34 weeks) for ventouse.

6) High likelihood of any fetal coagulation disorder for ventouse.

Question 64

In general, what are the pre-requisites for performing an instrumental delivery?

Answer 64

1) fully dilated

2) ruptured membranes

3) cephalic presentation

4) defined foetal position

5) foetal head at least at the level of the ischial spines, and no more than 1/5 palpable per abdomen

6) empty bladder

7) adequate pain relief

8) adequate maternal pelvis

Question 65

What presentation must the foetus be in to perform an instrumental delivery?

Answer 65

Cephalic presentation

Question 66

How are operative vaginal deliveries classified?

Answer 66

By the degree of foetal ascent:

1) Outlet
2) Low
3) Midline

The lower the classification, the less the risk of complications.

Question 67

What defines an ‘outlet’ classification of operative vaginal delivery?

Answer 67

Any of the following:

1) Fetal scalp visible with labia parted

2) Fetal skull reached pelvic floor

3) Fetal head on perineum

Question 68

What defines a ‘low’ classification of operative vaginal delivery?

Answer 68

Lowest presenting part (not caput) is +2, or further below the ischial spines.

Subdivided to:

> 45 degrees – rotation needed
<45 degrees – no rotation needed

Question 69

What defines a ‘midline’ classification of operative vaginal delivery?

Answer 69

1/5 palpable abdominally
Lowest part is above +2, but is lower than the ischial spines

Subdivided to:

> 45 degrees – rotation needed
<45 degrees – no rotation needed

Question 70

Give some foetal complications of an instrumental delivery

Answer 70

1) Neonatal jaundice

2) Scalp lacerations

3) Cephalhaematoma

4) Subgaleal haematoma

5) Facial bruising

6) Facial nerve damage

7) Skull fractures

8) Retinal haemorrhage

Question 71

Give some maternal complications of instrumental delivery

Answer 71

1) Vaginal tears

2) 3rd/4th degree tears

3) VTE

4) Incontinence

5) PPH

6) Shoulder dystocia

7) Infection

Question 72

Rarely an instrumental delivery may result in nerve injury for the mother.

What are the 2 most commonly affected nerves?

Answer 72

1) femoral nerve

2) obturator nerve

Question 73

How can the maternal femoral nerve be injured during instrumental delivery?

Answer 73

The femoral nerve may be compressed against the inguinal canal during a forceps delivery.

Question 74

How can injury to the maternal femoral nerve during instrumental delivery present?

Answer 74

1) weakness of knee extension

2) loss of patella reflex

3) numbness of anterior thigh and medial lower leg

Question 75

How can the maternal obturator nerve be injured during instrumental delivery?

Answer 75

May be compressed by forceps during instrumental delivery (or by the fetal head during normal delivery).

Question 76

How can injury to the maternal obturator nerve during instrumental delivery present?

Answer 76

1) weakness of hip adduction and rotation

2) numbness of medial thigh

Question 77

What are three other nerve injuries can occur during birth that are usually unrelated to instrumental delivery?

Answer 77

1) Lateral cutaneous nerve of the thigh

2) Lumbosacral plexus

3) Common peroneal nerve

Question 78

Where does the lateral cutaneous nerve of the thigh run?

Answer 78

Under the inguinal ligament

Question 79

How can the lateral cutaneous nerve of the thigh be injured during delivery?

Answer 79

Prolonged flexion at the hip while in the lithotomy position can result in injury.

Question 80

How does damage to the lateral cutaneous nerve of the thigh during delivery present?

Answer 80

Numbness of the anterolateral thigh.

Question 81

How can the lumbosacral plexus be injured during delivery?

Answer 81

The lumbosacral plexus may be compressed by the fetal head during the second stage of labour.

Question 82

How does damage to the lumbosacral plexus during delivery present?

Answer 82

Injury to this network of nerves nerve can cause foot drop and numbness of the anterolateral thigh, lower leg and foot.

Question 83

How can the common peroneal nerve be injured during delivery?

Answer 83

The common peroneal nerve may be compressed on the head of the fibula whilst in the lithotomy position.

Question 84

How does damage to the common peroneal nerve during delivery present?

Answer 84

Injury to this nerve causes foot drop and numbness in the lateral lower leg.