#178 Shoulder Dystocia Flashcards
Is shoulder dystocia predictable?
no
Is shoulder dystocia preventable?
no
What physically happens with a shoulder dystocia (why is baby stuck?)?
Descent of anterior shoulder is obstructed by the symphysis pubis or impaction of the posterior shoulder on the maternal sacral promontory
How do you diagnose shoulder dystocia?
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
What is the incidence of shoulder dystocia among vertex vaginal deliveries?
0.2-3%
A shoulder dystocia increases maternal risk for what complications?
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
What is the rate of postpartum hemorrhage after shoulder dystocia?
11%
What is the rate of fourth degree laceration after shoulder dystocia?
3.8%.
What is the total neonatal injury rate after shoulder dystocia? (according to a large multicenter study, n=2,018)
5.2% (erb palsy, klumpke palsy, clavicular or humeral fracture, hypoxic-ischemic encephalopathy)
What is the rate of brachial plexus injuries immediately after delivery c/b shoulder dystocia?
10-20%. Unknown complete recovery rate, possibly 50-80%
What % of infants having injury at C5-C6 or C5-C6-C7 levels after shoulder dystocia demonstrated complete recovery at 6 months?
64%
What % of infants having injury at C5-T1 levels after shoulder dystocia demonstrated complete recovery at 6 months?
14%
What % of infants (>3500g) had severe asphyxia in setting of shoulder dystocia?
0.8% (nondiabetic women) - 1% (diabetic women)
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?
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)
In a case series of fatal shoulder dystocias, what % had head-body delivery interval < 5 mins, what % > 10 minutes?
47% of cases were less than 5 minutes. Only 20% were greater than 10 minutes
True or false, most cases of shoulder dystocia occur in diabetic women with suspected macrosomia?
False. Diabetes and fetal macrosomia increase risk for shoulder dystocia, but more cases occur in nondiabetics with normal weight fetus
What is the probability of recurrent shoulder dystocia in a subsequent pregnancy?
Incidence of recurrent is at least 10%
Does ACOG recommend IOL for suspected macrosomia?
No, discourages IOL solely for suspected macrosomia at any gestational age
At what EFW should elective cesarean delivery be considered for women with or without diabetes who are carrying fetuses with suspected macrosomia?
5,000g for women without diabetes and 4,500g for women with diabetes
Is the presence of a brachial injury evidence that shoulder dystocia occurred?
No. Slightly more than 1/2 of all brachial plexus injuries are associated with uncomplicated vaginal deliveries
What proportion of brachial plexus injuries occur in infants that did not have a shoulder dystocia?
Slightly more than 1/2
When working to reduce a shoulder dystocia should you instruct the mother to continue pushing?
No, have mother stop pushing
What is the McRoberts maneuver and how does is physically help relieve shoulder dystocia?
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
What is the first maneuver that should be attempted with shoulder dystocia?
McRoberts maneuver
How do you instruct someone to apply suprapubic pressure to relieve shoulder dystocia?
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
Should you apply fundal pressure during a shoulder dystocia?
No. Can worsen impaction of the shoulder and may result in uterine rupture
If McRoberts maneuver and suprapubic pressure are unsuccessful in case of shoulder dystocia, what is the next maneuver to be performed?
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
The use of McRoberts + suprapubic pressure followed by delivery of posterior arm relieves what % of cases of shoulder dystocia within 4 minutes?
95%
What is the Rubin maneuver?
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.
What is the Woods Screw maneuver?
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
How do you use posterior axilla sling traction for a shoulder dystocia?
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
What is the Gaskin all-fours maneuver?
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.
When should you perform an episiotomy during shoulder dystocia?
Primarily reserved for cases in which additional access is needed to perform maneuvers.
What is the Zavanelli maneuver?
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.
What is abdominal rescue in regards to shoulder dystocia?
Laparotomy and hysterotomy facilitate manual dislodging of the anterior shoulder from above, then effecting vaginal delivery
What is the role of clavicular fracture, and how to perform it, in cases of shoulder dystocia?
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
Does shoulder dystocia simulation training decrease incidence of brachial plexus injuries?
Yes
