+ Shoulder Dystocia Review July 24, 2014 Marie-Claude Laplante Paula Tchen MS3.
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Transcript of + Shoulder Dystocia Review July 24, 2014 Marie-Claude Laplante Paula Tchen MS3.
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Shoulder Dystocia ReviewJuly 24, 2014
Marie-Claude LaplantePaula TchenMS3
Objectives
10553 Propose & execute immediate management of shoulder Dystocia.
10554 Describe options if immediate management of shoulder Dystocia is not successful.
Definition
Abnormal labour or dystocia (means difficult labour or childbirth)
Occasionally referred to as failure to progress.
A vaginal delivery is complicated by shoulder dystocia when, after delivery of the fetal head, additional obstetric maneuvers beyond gentle traction are needed to enable delivery of the fetal shoulders.
*leading indication for primary C/S in the US
variability in the diagnosis, management and criteria for dystocia
Rarely diagnosed with certainty
Pathophysiology of shoulder dystocia
During delivery the anterior shoulder should slide under the symphysis pubis. If the fetal shoulders remain in an anterior-posterior position during descent or descend simultaneously rather than sequentially into the pelvic inlet, then the anterior shoulder can become impacted behind the symphysis pubis; the posterior shoulder may be obstructed by the sacral promontory. Anterior obstruction is more common than posterior obstruction. If descent of the fetal head continues while the anterior or posterior shoulder remains impacted, then stretching of the nerves in the brachial plexus may occur and may result in nerve injury.
If fetal head is turned to one side (asynclitism) or extended (extension) the cephalic diameter is increased. Brow presentation can cause dystocia if it does not convert to vertex or face.
Epidemiology of shoulder dystocia
.2-3% of all births
Can you predict a shoulder dystocia?
NO! most often cannot predict and occur in the absence of risk factors.
+Factors that contribute to normal labour
What are the factors that contribute to normal labour?
Power
Passenger
Position
+
Increased fetal birthweight Increased risk with weight over 4000g.
Macrosomia is >4500g. With increasing weight, risk will increase.
Post-term, excessive weight gain during pregnancy>35lbs, parity
Diabetes Midforceps delivery Prolonged first/second stage? Prior shoulder dystocia Maternal height: more risk among shorter
parturients <150cm
Risk Factors
+Diagnosis
Head to body delivery time exceeding 60s
Friedman’s curve to assess labour
Abnormal labour patterns:
1)prolonged latent phase; more than 20 hours in nulliparous or 14h in multiparous.
2)active labour: cervix dilates less than 1cm/hour nulliparous or less than 1.2-1.5cm/hour multiparous
+Management
Reduction maneuvers – HELPERR Mnemonic Call for Help Evaluate for Episiotomy Legs (McRoberts Maneuver) Suprapubic Pressure Enter maneuvers (internal rotation) Removal of the posterior arm Roll the patient
+Management - Rubin
+Management – Wood’s corkscrew
+Management
Reduction maneuvers – HELPERR Mnemonic What we’re trying to accomplish:
Increase functional size of the bony pelvis Decrease the bisacromial diameter (breadth of the
shoulders) Change the relationship of the bisacromial diameter
within the bony pelvis
+Management
http://www.youtube.com/watch?v=j_bibDLPW98&noredirect=1
+Management
If those maneuvers fail: Last resort:
Deliberate clavicule fracture Zavanelli maneuver General anesthesia Cesarian section Symphysiotomy
+Prophylactic management
Typically, you can’t predict, so you can’t prevent!
(ACOG) Task Force on Neonatal Brachial Plexus Palsy clinical situations as high risk for shoulder dystocia and brachial plexus injury: Estimated fetal weight >5000 g in women without diabetes
or >4500 g in women with diabetes Prior shoulder dystocia, especially with a severe neonatal
injury Midpelvic operative vaginal delivery of a fetus with estimated
weight >4000 g
*Cesarean section is a reasonable option for these patients, but is discussed as a case by case basis.
+Complications
Remember: diagnosis and timing are key
Why? Avoid complications: Fetal:
Asphyxia Cortical injury due to cord compression and asphyxia Transient/permanent brachial plexus palsy Clavicular or humeral fracture Death
Maternal: Hemorrhage Fourth degree lacerations
Clinical case: Shoulder dystocia A 30 yo G2P1 is delivering at 41 weeks gestation. She
is moderately obese, but the fetus appears to clinically weigh approximately 3700 g. After a 4-hour first stage of labor and 2-hr second stage of labor, the fetal head delivers but is noted to then retract back toward the patient’s introitus (turtle sign). The fetal shoulders do not deliver, despite strong maternal pushing.
Diagnosis
Risk Factors
Management Principles of this Obstetric Emergency/ Initial Maneuvers to manage this condition
Review Neonatal and Maternal Complications of this event
+Case discussion
• fetal weight (passenger) estimation is inaccurate. If weight is greater than 4000-4500g the risk of dystocia including shoulder dystocia and fetopelvic disproportion is greater. Fetal macrosomia defined as birthweight over 4500g(ACOG)
• 2 hour second stage- for multiparas we limit to one hour or 2 hours with regional analgesia- for nulliparas limit to 2 h or 3 h with regional analgesia
• Rates of chorioamnionitis, PPH, instrumental delivery, Cesarean section and perineal trauma increase with increasing length of the active second stage of labour.
• What is significance of turtle sign? May herald shoulder dystocia
• Risk factors in this case : maternal obesity, pelvis ?- anatomy unknown (mother is G2 but first baby premature). No prior history of dystocia in this case. No history of diabetes. Mother’s height unknown.
+References
Baxley, E; Gobbo, R. Shoulder Dystocia 2004 American Family Physican, 69(7), p. 1707-1714
Beckmann et al. Obstetrics and Gynecology. 7th edition 2014 Lippincottt Williams & Williams.
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