Shoulder Dystocia

Question 1

What is the incidence of shoulder dystocia?

Answer 1

0.58 - 0.7 %
1/200 ( oxford )

Question 2

How shoulder dystocia occurs?

Answer 2

When either the anterior or less common the posterior fetal shoulder impacts on the maternal symphysis or sacral promontory

Question 3

What are the most important maternal complications caused by shoulder dystocia?

Answer 3

1- PPH 11 %
2- 3rd & 4th degree perineal tears 3,8%
Other: 1-bladder rupture/
2- uterine rupture/
3-symphyseal separation/
4- sacroiliac dislocation/
5-lateral fumeral cutaneous neuropathy

Question 4

What is the most important fetal complication of shoulder dystocia?

Answer 4

Brachial plexus injury BPI 2,3 - 16 %

Question 5

What is the incidence of brachial plexus injury BPI in UK ? What is the prognosis?

Answer 5

0.43 per 1000 live birth
Most of the cases resolve without permanent disability
10 % resulting permanent neurological dysfunction

Question 6

What is the percentage of babies with BPI are born after CS?

Answer 6

4 - 12 % of them
It is important legally to determine whether the affected shoulder was anterior or posterior: ( posterior is unlikely to be due to action by doctor)

Question 7

Can shoulder dystocia be predicted by making risk assessment?

Answer 7

Risk assessment of shoulder dystocia is insufficiently predictive to allow prevention
Predicted only 16 % of shoulder dystocia

Question 8

What is the relationship between shoulder dystocia and fetal size?

Answer 8

Not good predictor
Majority of infants > 4500 g don’t develop shoulder dystocia
48% of shoulder dystocia occurs with infants < 4000 g

Question 9

Infants of diabetic women have an increased risk of shoulder dystocia compared with infants of the same weight born to non diabetic women,
How much is the increase?

Answer 9

2 - 4 folds

Question 10

Is third trimester ultrasound scan a reliable method to predict macrosomia?

Answer 10

Sensitivity 60 % to predict macrosomia
🚩has at least 10 % margin for error for actual birth weight

Question 11

What are the factors associated with shoulder dystocia pre labour?

Answer 11

1- previous shoulder dystocia
2- macrosomia > 4,5 kg
3- diabetes Mellitus
4- maternal BMI > 30
5- induction of labour

Question 12

What are the intrapartum factors associated with shoulder dystocia ?

Answer 12

1- prolonged first stage
2- secondary arrest
3- prolonged second stage
4- oxytocin augmentation
5- assisted vaginal delivery

Question 13

Does early induction of labour prevent shoulder dystocia?

Answer 13

ℹ Only in women with gestational diabetes who have a normally grown fetus after 38 w
⛔ does not prevent shoulder dystocia in non diabetic women with a suspected macrosomic fetus

Question 14

Should elective CS be recommended for suspected fetal macrosomia to prevent brachial plexus injury BPI ?

Answer 14

Elective CS should be considered:
In pregnancies complicated by preexisting or gestational diabetes regardless of treatment, with an estimated fetal weight > 4500 g

Question 15

What are the recommendations of ACOG about the delivery of a fetus has EFW over 5 kg ?

Answer 15

Consideration of CS

Question 16

What is the recurrence rate of shoulder dystocia?

Answer 16

1 - 25 %
The rate of shoulder dystocia in women who had Previous shoulder dystocia 10 times higher general population

Question 17

Is previous shoulder dystocia an indication for CS ?

Answer 17

It is not recommended but risk factors should be considered

Question 18

How is shoulder dystocia diagnosed? ( signs of shoulder dystocia)?

Answer 18

1- difficulty with delivery of the face and chin
2- the remaining tightly applied to the valva or retracted
3- failure of restitution of the head
4- failure of the shoulders to descend
⛔ routine traction in an axial direction can be used to diagnose shoulder dystocia

Question 19

Does prophylactic McRobert position before the delivery of the fetal head prevents shoulder dystocia?

Answer 19

It is not recommended
Dosen’t prevent shoulder dystocia

Question 20

How should shoulder dystocia be managed?

Answer 20

1- CALL FOR HELP: additional midwife/ experience obstetrician/ neonatal team / anaesthetist
2- Don’t do downward traction
3- DISCOURAGE pushing
4- fundal pressure should NOT be used
5- Mcroberts maneuver
6- suprapubic pressure
7- consider episiotomy
8- do either : * deliver posterior arm
* internal rotational manoeuvres
8- repeat all above
9- consider: cleidotomy / Zavanelli/ or symphysiotomy

Question 21

Why is it important to manage shoulder dystocia as efficient as possible?

Answer 21

47 % of the babies that died did so within 5 minutes of the head being delivered ( with pathological CTG)
⚠️ very low rate of hypoxia if the head to body time was less than 5 minutes

Question 22

What is the success rate for Mcroberts maneuver?

Answer 22

90 %

Question 23

What is the role of episiotomy in the management of shoulder dystocia?

Answer 23

Doesn’t decrease the risk of BPI with shoulder dystocia
ONLY be considered if internal vaginal access is needed for the delivery of posterior arm or internal rotation of the shoulders

Question 24

What measures should be undertaken if Mcroberts maneuver & suprapubic pressure fail ?

Answer 24

Internal manoeuvr OR all fours position
Should be used

Question 25

What are the internal manoeuvres ( woods & Robin ) ( Woodscrew manoeuvre ) in the management of shoulder dystocia?

Answer 25

*Gaining access posteriorly in the sacral hollow
1- rotation into oblique diameter
( by pressing the anterior or posterior aspect of the posterior shoulder
OR full 180 degree rotation of the trunk
2- delivery of the posterior arm

Question 26

What is the success rate of all fours position in the management of shoulder dystocia?

Answer 26

83 %

Question 27

What is the incidence of humeral fractures associated with delivery of the posterior arm ?

Answer 27

2- 17 %

Question 28

In which case all fours position is more appropriate than internal manoeuvres in the management of shoulder dystocia?

Answer 28

Slim mobile woman without epidural anaesthesia, with single midwife attendant

Question 29

What is “ Zavanelli maneuver “?

Answer 29

Vaginal head replacement then delivery by CS
* bilateral shoulder dystocia
* most of fetuses have hypoxic acidosis by this stage & may Not reduce the risk of BPI

Question 30

Beside BPI what are the fetal injuries associated with shoulder dystocia?

Answer 30

1-Fractures of the humerus & clavicle
2- pneumothoraces
3- hypoxic brain damage

Question 31

What to write in documentation in a case of shoulder dystocia?

Answer 31

1- time of delivery of the head & time of delivery of the body
2- anterior shoulder at the time of the delivery
3- manoeuvres performed, their timing & sequence
4- maternal perineal & vaginal examination
5- estimated blood loss
6- staff in attendance & the time they arrive
7- abgar score of the baby
8- umbilical cord blood acid base measurements
9- neonatal assessment of the baby
* document the position of the fetal head at delivery

Question 32

What is the prophylactic measures to reduce the risk of PPH in a case of shoulder dystocia?

Answer 32

40 iu oxytocin