Shoulder Dystocia/Cord Prolapse Flashcards
Define shoulder dystocia
Vaginal cephalic delivery that requires additional obstetric manoeuvres to deliver the fetus after the head has delivered and gentle traction has failed
List the associations and risk factors of shoulder dystocia
Maternal:
- Diabetes mellitus
- Obesity
Fetal:
- Large for gestational age
- Macrosomia >4.5kg
- Post-maturity
What is the incidence of shoulder dystocia?
0.6-0.7% (RCOG - Greentop 42, 2012)
How do we manage shoulder dystocia?
HELPERR
H = Call for Help E = Evaluate for Episiotomy L = Legs - McRoberts manoeuvre P = External Pressure - suprapubic E = Enter - rotational manoeuvres R = Remove the posterior arm R = Roll the patient to her hands and knees
*If all this fails, repeat or use surgical manoeuvres
What is the McRoberts manoeuvre?
- Flexion and abduction of maternal hips, positioning the maternal thighs on her abdomen
- Increases relative AP diameter of pelvis
- Success rate = 90%
Why do we apply suprapubic pressure?
- Reduces the fetal bisacromial diameter and rotates the anterior shoulder into the wider oblique pelvic diameter
- Shoulder then freed to slip under the symphysis pubis with routine axial traction
What are the internal rotational manoeuvres?
- Woods and Rubin
- Rotation most easily achieved by pressing on anterior or posterior aspect of posterior shoulder
- Pressure on posterior aspect of posterior should also reduces shoulder diameter by adducting the shoulders
- Shoulders should be rotated into wider oblique diameter
- If posterior shoulder unsuccessful, pressure should be applied to posterior aspect of anterior shoulder
Why and how do we remove the posterior arm?
- Reduces diameter of fetal shoulders by width of the arm
- Fetal wrist should be grasped and the posterior arm should be gently withdrawn from the vagina in a straight line
- Associated with humeral fractures (2-12%)
What is the positional change that the patient should adopt if other manoeuvres fail?
- All fours position
- 83% success rate
List the surgical manoeuvres that can be performed if all others fail
- Zavanelli manoeuvre
- Symphysiotomy
- Cleidotomy
What is the Zavanelli manoeuvre?
Vaginal replacement of the head and then delivery by C-section
What is a symphysiotomy?
Dividing the anterior fibres of the symphyseal ligament
What is a cleidotomy?
Surgical division of the clavicle of the fetus or bending with a finger
List the fetal complications of shoulder dystocia
- Brachial plexus injuries (Erb’s palsy [C5-C6] most common, also T1 and C8 injuries, rarely T4 injuries) 2-16%
- Hypoxic brain damage
- Fractured clavicle, fractured humerus
- Pneumothorax
- Death
List the maternal complications of shoulder dystocia
- PPH
- Third and fourth degree perineal tears (3.8%)
- Vaginal lacerations
- Cervical tears
- Rupture - bladder/uterus
- Symphyseal separation
- Sacroiliac joint dislocation
- Lateral femoral cutaneous neuropathy
Define cord prolapse
Descent of the umbilical cord through the cervix alongside (occult) or past (overt) the presenting part in the presence of ruptured membranes
Define cord presentation
The presence of the umbilical cord between the fetal presenting part and the cervix, with or without intact membranes
Why is cord prolapse important?
ASPHYXIA:
- Cord compression
- Umbilical arterial spasm (cold air outside uterus causes this)
PMR = 91 per 1000
What is the incidence of cord prolapse?
0.1-0.6%
What factors are associated with cord prolapse?
General:
- Multiparity
- Low birthweight (<2.5kg)
- Preterm labour (<37wks)
- Fetal congenital anomalies
- Breech presentation
- Transverse, oblique and unstable lie
- Second twin
- Polyhydramnios
- Unengaged presenting part
- Low lying placenta
Procedural:
- ARM with high presenting part
- Vaginal manipulation of fetus with ruptured membranes
- External cephalic version (ECV)
- Internal podalic version
- Stabilising induction of labour
- Insertion of intrauterine pressure transducer
- Large balloon catheter IOL
What is the management of cord prolapse?
CORD
C = Consider O = Organise help R = Relive pressure D = Decision for birth
When should we consider?
- At every VE during labour
- Abnormal fetal heart with SROM
- Membrane rupture with risk factors
What help should be organised?
- Obstetricians and midwives
- Anaesthetist and perioperative team
- Neonatal team
- Porter
How can we relive pressure?
- Manually elevate presenting part or fill bladder
- Encourage into knee chest position OR left lateral position with pillow placed under left hip
- Consider tocolysis (Terbutaline beta 2 agonist)
