Shoulder DystociaShoulder Dystocia

( ACOG Medical Student Education Module 2011)( ACOG Medical Student Education Module 2011)

DefinitionDefinition

Difficulty in delivery of fetal shouldersDifficulty in delivery of fetal shoulders Failure to deliver fetal shoulder without Failure to deliver fetal shoulder without

utilizing facilitating maneuversutilizing facilitating maneuvers Prolonged head-to-body delivery timeProlonged head-to-body delivery time

>60 seconds>60 seconds

Incidence: 0.2-3% of all live births; Incidence: 0.2-3% of all live births; represents an obstetric emergencyrepresents an obstetric emergency

Bilateral Shoulder Dystocia

The posterior shoulder is not in the hollow of the pelvis.

This presentation often requires a cephalic replacement.

Unilateral Shoulder Dystocia

Unilateral shoulder dystocia is usually easilydealt with by standard techniques.

PathophysiologyPathophysiology

Size discrepancy between fetal shoulders Size discrepancy between fetal shoulders and maternal pelvic inletand maternal pelvic inlet MacrosomiaMacrosomia Large chest:BPDLarge chest:BPD Absence of truncal rotationAbsence of truncal rotation

Fetal shoulders remain A-P or descent Fetal shoulders remain A-P or descent simultaneouslysimultaneously

Risk FactorsRisk Factors AntepartumAntepartum

Macrosomia (>4500g ACOG)Macrosomia (>4500g ACOG) GDM (increases overall risk by 70%)GDM (increases overall risk by 70%) MultiparityMultiparity

IntrapartumIntrapartum Prolonged deceleration phase of laborProlonged deceleration phase of labor Prolonged 2Prolonged 2ndnd stage stage Protracted descentProtracted descent Operative delivery (vacuum>forceps)Operative delivery (vacuum>forceps)

DD - Diabetes - Diabetes OO- Obesity- Obesity PP- Post term pregnancy, prior large baby- Post term pregnancy, prior large baby EE- Excessive weight gain during - Excessive weight gain during

pregnancypregnancy

No evidence based data:No evidence based data: MaleMale Short maternal statureShort maternal stature Abnormal pelvic shape/sizeAbnormal pelvic shape/size

UnpredictableUnpredictable 25-50% have no defined risk factor!25-50% have no defined risk factor!

50% of cases occur in infants whose birth weight is 50% of cases occur in infants whose birth weight is <4000g<4000g

TURTLE SIGNTURTLE SIGN: represented by the retraction of the : represented by the retraction of the fetal head after expulsion, fetal head after expulsion, maymay herald shoulder herald shoulder dystocia, shoulder dystocia is not diagnosed until the dystocia, shoulder dystocia is not diagnosed until the usual attempts at the delivery of the head fail.usual attempts at the delivery of the head fail.

ComplicationsComplications

MaternalMaternal HemorrhageHemorrhage 44thth degree laceration degree laceration

FetalFetal Fx of humerus or clavicle Fx of humerus or clavicle Brachial plexus injury (Erb’s/Klumpke’s palsy)Brachial plexus injury (Erb’s/Klumpke’s palsy) Asphyxia/cord compressionAsphyxia/cord compression

PhysicianPhysician Litigation: 11% of all obstetrical suitsLitigation: 11% of all obstetrical suits

ManagementManagement

Goal: Safe delivery before neontal asphyxia Goal: Safe delivery before neontal asphyxia and/or cortical injuryand/or cortical injury

7 minutes7 minutes!!!!!! EpisiotomyEpisiotomy Suprapubic PressureSuprapubic Pressure McRoberts ManeuverMcRoberts Maneuver Woods or Rubin ManeuversWoods or Rubin Maneuvers ZavenelliZavenelli

Push back the delivered fetal head into birth canal and Push back the delivered fetal head into birth canal and perform an emergent c/sperform an emergent c/s

HELPERR Algorithm H: Call for Help; Shoulder dystocia is

called if shoulders cannot be delivered with gentle traction

E: Evaluate for Episiotomy: Not routinely indicated; maybe needed when attempting intra-vaginal maneuver

L: Legs (McRoberts): Hyperflexion and abduction of hips—initial maneuver

P (Suprapubic Pressure): No fundal pressure; combination of McRoberts and suprapubic pressure resolves most shoulder dystocias

Enter (Internal Maneuvers): oblique diameter rotational maneuvers Woods screw (1943): Insert two fingers into posterior vagina and

apply pressure to the anterior aspect (clavicular) of the posterior shoulder and abduct and rotate that shoulder, the posterior shoulder could be rotated 180° degrees to the anterior, and this would disimpact the obstructed anterior shoulder. The subsequent addition of gentle downward traction with a contraction would then result in delivery.

Rubin(1964): either the anterior or posterior shoulder, which ever was more accessible, be adducted and brought toward the fetal chest. Insert two fingers on the posterior aspect (scapular) of the anterior or posterior shoulder and also rotate the baby 180° to reduce the obstruction.

Remove: Delivery posterior arm

Roll the patient: Gaskin maneuver or all four positions

McRoberts ManeuverMcRoberts Maneuver

42% success rate42% success rate + Suprapubic pressure = 54-58%+ Suprapubic pressure = 54-58%

Brings pelvic inlet and outlet into more vertical Brings pelvic inlet and outlet into more vertical alignmentalignment

Flattens sacrumFlattens sacrum Cephalad rotation of pubic symphysisCephalad rotation of pubic symphysis Elevates anterior shoulder and flexes fetal spineElevates anterior shoulder and flexes fetal spine Increases IUP by 97%Increases IUP by 97% Increases amplitude of contractionsIncreases amplitude of contractions +31N of pushing force+31N of pushing force

Preliminary Measures:

Gentle pressure on the fetal vertex in a dorsal direction will move the posterior fetal shoulder deeper into the maternal pelvic hollow, usually resulting in easy delivery of the anterior shoulder.

Excession angulation (>45 degrees) is to be avoided.

(Gabbe, et al., Obstetrics: Normal and Problem Pregnancies, Churchill Livingstone, New York, 1986)

The McRoberts manoeuvre

Suprapubic Pressure Moderate suprapubic pressure is often the

only additional maneuver necessary to disimpactthe anterior fetal shoulder. Stronger pressure canonly be exerted by an assistant.

(Gabbe, et al., 1986)

Delivery may be facilitated by counterclockwiserotation of the anterior shoulder to the morefavorable oblique pelvic diameter, or clockwise rotation of the posterior shoulder.

During these maneuvers, expulsive efforts should be stopped and the head is never grasped !!

Oblique Diameter Rotational Maneuver

Delivery of the Posterior Arm

To bring the fetal wrist within reach, exert pressure with the index finger at the antecubital junction.

(E. Sandberg. American Journal of Obstetrics and Gynecology, 1985; 152: 481.)

Sweep the fetal forearm down over the front of the chest.

Delivery of the Posterior Arm

If less invasive maneuvers fail to affect this impaction, delivery should be facilitated by manipulative delivery of the posterior arm by inserting a hand into the posterior vagina and ventrally rotating the arm at the shoulder with delivery over the perineum.

Delivery of the Posterior Arm

All- Fours Manoeuver

It consists of placing the patient onto It consists of placing the patient onto her hands and knees her hands and knees

The Chavis Maneuver

Described in 1979. A “shoulder horn” consisting of a concave

blade with a narrow handle is slipped between the symphysis and the impacted anterior shoulder.

This used like a shoe-horn as a lever where the symphysis is the fulcrum.

Release of the anerior shoulder is initiated by firm pressure against the infant's jaw and neck in a posterior and upward direction. An assistant is poised, ready to apply fundal pressure after proper suprapublic pressure

As the anterior shoulder slips free, fundal pressure is applied, and pressure against the neck is shifted slightly toward the rectum.Proper suprapubic pressure is continued.

The Hibbard Maneuver

The Hibbard Maneuver

Continued fundal and suprapublic pressure results in an upward-inward rotation of the newly freed anterior shoulder and a further descent in a position beneath the pubic symphysis.

As a result of the previous maneuvers, the transverse diameter of the shoulders is reduced.

Lateral (upward) flexion of the head releases the posterior shoulder into the hollow of the sacrum.

The Hibbard Maneuver

Fracture of the Clavicle

The anterior clavicle is pressed against the ramis of the pubis.

Care should be taken to avoid puncturing the lung by angling the fracture anteriorly.

Theoretically, a fracture of the clavicle is less serious than a brachial nerve injury and often heals rapidly.

The Zavanelli Maneuver

First described in 1988 Consists of cephalic replacement and

then cesarean delivery. Mixed reviews in the literature.

SummarySummary

Cannot accurately predictCannot accurately predictBE PREPARED!BE PREPARED!

Consider risk factorsConsider risk factors Be prepared to perform various maneuversBe prepared to perform various maneuvers Diagnose and treat quicklyDiagnose and treat quickly Obtain assistance from nursing staff and Obtain assistance from nursing staff and

NICUNICU

Prophylactic Cesarean?Prophylactic Cesarean?

Not recommended by ACOGNot recommended by ACOG Exceptions:Exceptions:

Consider if…Consider if… >5000g in mother without DM>5000g in mother without DM

>4500g in mother with DM>4500g in mother with DM

Shoulder dystocia is well suited for simulation training.

The obstetric birth simulator NOELLE (Gammard Scientific, FL, USA) is one such model.