#178 Shoulder Dystocia

Question 1

Is shoulder dystocia predictable?

Answer 1

no

Question 2

Is shoulder dystocia preventable?

Answer 2

no

Question 3

What physically happens with a shoulder dystocia (why is baby stuck?)?

Answer 3

Descent of anterior shoulder is obstructed by the symphysis pubis or impaction of the posterior shoulder on the maternal sacral promontory

Question 4

How do you diagnose shoulder dystocia?

Answer 4

Most commonly diagnosed as failure to deliver the fetal shoulder(s) with gentle downward traction on the fetal head, requiring additional obstetric maneuvers to effect delivery

Question 5

What is the incidence of shoulder dystocia among vertex vaginal deliveries?

Answer 5

0.2-3%

Question 6

A shoulder dystocia increases maternal risk for what complications?

Answer 6

Increased risk of postpartum hemorrhage as well as higher degree perineal lacerations. Maternal symphyseal separation and lateral femoral cutaneous neuropathy have been shown to be associated with aggressive hyperflexion

Question 7

What is the rate of postpartum hemorrhage after shoulder dystocia?

Answer 7

11%

Question 8

What is the rate of fourth degree laceration after shoulder dystocia?

Answer 8

3.8%.

Question 9

What is the total neonatal injury rate after shoulder dystocia? (according to a large multicenter study, n=2,018)

Answer 9

5.2% (erb palsy, klumpke palsy, clavicular or humeral fracture, hypoxic-ischemic encephalopathy)

Question 10

What is the rate of brachial plexus injuries immediately after delivery c/b shoulder dystocia?

Answer 10

10-20%. Unknown complete recovery rate, possibly 50-80%

Question 11

What % of infants having injury at C5-C6 or C5-C6-C7 levels after shoulder dystocia demonstrated complete recovery at 6 months?

Answer 11

64%

Question 12

What % of infants having injury at C5-T1 levels after shoulder dystocia demonstrated complete recovery at 6 months?

Answer 12

14%

Question 13

What % of infants (>3500g) had severe asphyxia in setting of shoulder dystocia?

Answer 13

0.8% (nondiabetic women) - 1% (diabetic women)

Question 14

In a case series of six hypoxic-ischemic encephalopathy cases after shoulder dystocia, what was # of maneuvers used and the mean time between delivery of head and remainder of body?

Answer 14

All associated with the use of more than 5 maneuvers. Mean time between delivery of head and remainder of body was 10.75 minutes (range 3-20 mins)

Question 15

In a case series of fatal shoulder dystocias, what % had head-body delivery interval < 5 mins, what % > 10 minutes?

Answer 15

47% of cases were less than 5 minutes. Only 20% were greater than 10 minutes

Question 16

True or false, most cases of shoulder dystocia occur in diabetic women with suspected macrosomia?

Answer 16

False. Diabetes and fetal macrosomia increase risk for shoulder dystocia, but more cases occur in nondiabetics with normal weight fetus

Question 17

What is the probability of recurrent shoulder dystocia in a subsequent pregnancy?

Answer 17

Incidence of recurrent is at least 10%

Question 18

Does ACOG recommend IOL for suspected macrosomia?

Answer 18

No, discourages IOL solely for suspected macrosomia at any gestational age

Question 19

At what EFW should elective cesarean delivery be considered for women with or without diabetes who are carrying fetuses with suspected macrosomia?

Answer 19

5,000g for women without diabetes and 4,500g for women with diabetes

Question 20

Is the presence of a brachial injury evidence that shoulder dystocia occurred?

Answer 20

No. Slightly more than 1/2 of all brachial plexus injuries are associated with uncomplicated vaginal deliveries

Question 21

What proportion of brachial plexus injuries occur in infants that did not have a shoulder dystocia?

Answer 21

Slightly more than 1/2

Question 22

When working to reduce a shoulder dystocia should you instruct the mother to continue pushing?

Answer 22

No, have mother stop pushing

Question 23

What is the McRoberts maneuver and how does is physically help relieve shoulder dystocia?

Answer 23

Two assistants each grasp a maternal leg and sharply flex the thigh back against the abdomen. Causes cephalad rotation of the symphysis pubis and flattening of the lumbar lordosis that can free the impacted shoulder

Question 24

What is the first maneuver that should be attempted with shoulder dystocia?

Answer 24

McRoberts maneuver

Question 25

How do you instruct someone to apply suprapubic pressure to relieve shoulder dystocia?

Answer 25

Assistant applies pressure above the pubic bone with the palm or fist, directing the pressure on the anteiror shoulder both downward (to below pubic bone) and laterally (toward the fetus’s face or sternum) in order to abduct and rotate the anterior shoulder

Question 26

Should you apply fundal pressure during a shoulder dystocia?

Answer 26

No. Can worsen impaction of the shoulder and may result in uterine rupture

Question 27

If McRoberts maneuver and suprapubic pressure are unsuccessful in case of shoulder dystocia, what is the next maneuver to be performed?

Answer 27

Delivery of the posterior arm, high degree of success in accomplishing delivery. Requires the least amount of force and lowest amount of brachial plexus stretch

Question 28

The use of McRoberts + suprapubic pressure followed by delivery of posterior arm relieves what % of cases of shoulder dystocia within 4 minutes?

Answer 28

95%

Question 29

What is the Rubin maneuver?

Answer 29

Maneuver to help relieve shoulder dystocia where you place your hand on the back surface of the posterior fetal shoulder, then rotate it anteriorly towards the fetal face.

Question 30

What is the Woods Screw maneuver?

Answer 30

Maneuver to help relieve shoulder dystocia where you rotate the fetus by exerting pressure on the anterior, clavicular surface of the posterior shoulder to turn the fetus until the anterior shoulder emerges

Question 31

How do you use posterior axilla sling traction for a shoulder dystocia?

Answer 31

Thread a size 12 or 14 French soft catheter to create a sling around posterior shoulder, allowing the shoulder to be delivered by applying moderate traction to the sling

Question 32

What is the Gaskin all-fours maneuver?

Answer 32

Maneuver to help relieve shoulder dystocia, used for women without anesthesia. Woman placed on hands and knees and delivery is effected by gentle downward traction on the posterior shoulder or upward traction on the anterior shoulder.

Question 33

When should you perform an episiotomy during shoulder dystocia?

Answer 33

Primarily reserved for cases in which additional access is needed to perform maneuvers.

Question 34

What is the Zavanelli maneuver?

Answer 34

Cephalic replacement followed by cesarean delivery. Described for relieving catastrophic cases of shoulder dystocia. Associated with significantly increased risk of fetal morbidity and mortality and maternal morbidity.

Question 35

What is abdominal rescue in regards to shoulder dystocia?

Answer 35

Laparotomy and hysterotomy facilitate manual dislodging of the anterior shoulder from above, then effecting vaginal delivery

Question 36

What is the role of clavicular fracture, and how to perform it, in cases of shoulder dystocia?

Answer 36

May help decrease bisacromial diameter. Performed by pulling the anterior clavicle outward. May be difficult to perform and can be associated with injury to underlying structures

Question 37

Does shoulder dystocia simulation training decrease incidence of brachial plexus injuries?

Answer 37

Yes