Gnosis shoulder dystocia

Question 1

ACOG definition of shoulder dystocia?

Answer 1

Delivery requiring additional maneuvers following failure of gentle downward traction on fetal head to deliver shoulders - or if it takes >60s between delivery of neck and shoulders

Question 2

Turtle sign?

Answer 2

Fetal head retracts into the perineum after expulsion

Question 3

Incidence of shoulder dystocia?

Answer 3

0.2-3% of all vaginal deliveries

Question 4

When would you offer a C-section to women at risk of dystocia?

Answer 4

EFW >5000g if nondiabetic, >4500g if diabetic (larger AC, shoulder fat distribution makes it difficult to deliver), h/o midpelvic operative vaginal delivery with EFW >4000g, prior shoulder dystocia

Question 5

Complications of shoulder dystocia?

Answer 5

Postpartum hemorrhage, fourth degree lacs, brachial plexus injuries, hypoxic-ischemic encephalopathy, death

Question 6

Definition of hypoxic-ischemic encephalopathy?

Answer 6

Cord bloods with pH<7 and base deficit >12mmol/mL, early onset encephalopathy in infant >34w, cerebral palsy of spastic quadriplegic or dyskinetic type AND exclusion of other causes

Question 7

Major risks for shoulder dystocia?

Answer 7

Macrosomia (over half involve infants >4000g), DM (increases risk by 2-6x), midpelvic operative vaginal delivery, prior dystocia (1-25% risk of recurrence)

Question 8

Minor risks for shoulder dystocia?

Answer 8

Postterm pregnancy (more after >42w likely d/t fetal size), maternal obesity, excessive gestational weight gain (>33lbs), male fetus (more prone to macrosomia), prolonged labor, precipitous delivery

Question 9

Primary maneuvers for resolving shoulder dystocias?

Answer 9

McRoberts and suprapubic pressure (to adduct shoulders and decrease shoulder diameter - done in the direction towards where baby is facing, otherwise it’ll abduct the shoulders instead)

40% of dystocias resolve with McRoberts alone, 58% with suprapubic pressure

Question 10

Secondary maneuvers for resolving shoulder dystocias?

Answer 10

Posterior arm delivery (2 fingers into vagina to bend posterior arm at elbow, sweep in front of face, pull arm out to deliver), Rubin (use fingers of 1 hand to push from posterior aspect of either shoulder to push shoulder inward towards the chest and rotate baby obliquely to dislodge anterior shoulder), Woods screw (2 fingers to push from anterior aspect of posterior shoulder to rotate baby 180 degrees), Gaskin (mom on all 4s)

Notes:
- Posterior arm should be the first go-to

• Nurse should release suprapubic pressure and relax McRoberts to give more room; no pushing for the Rubin or Woods screw; may need terbutaline to relax uterus
• Episiotomy often helps give room
• With Woods screw, if 1 hand doesn’t work can add 2 fingers of other hand on posterior aspect of anterior shoulder and use both hands to rotate fetus (modified Woods screw maneuver)
• Reverse Woods screw = Rubin on posterior shoulder
• Gaskin may disimpact shoulder just by the movement, can also widen sagittal diameter of pelvis and help work with gravity to move posterior shoulder anteriorly to pass over the sacral promontory → 1998 study (n=82) resolved 83% of dystocias with Gaskin alone

Question 11

Desperation maneuvers for resolving shoulder dystocias?

Answer 11

Zavanelli (flex fetal head and return to intravaginal position and go for C-section), abdominal rescue (mom in lithotomy position → open anterior abdominal wall to expose uterus and apply direct pressure on the uterine wall to push baby’s shoulder out from above → if this fails can do a hysterotomy and continue to push on anterior fetal shoulder), intentional clavicle fracture (hook 1-2 fingers under the clavicle and apply upward pressure towards fetal head at midpoint to minimize risk of vascular damage)

Notes:
- Anterior shoulder rescue with hysterotomy can allow anterior shoulder to pop through the incision → can then deliver the posterior arm vaginally

• Can try anterior shoulder rescue right before Zavanelli since it can spare you a hysterotomy if pressure on the uterus is sufficient
• May need anesthesia to help relax the uterus with halogenated anesthetic gas; with Zavanelli some sources recommend use of terbutaline for uterine relaxation
• Cleidotomy - cutting clavicle with scissors; avoid in live fetuses because of risk of compound fx, trauma to pleural cavity, increased infection risk