see ED Mx of 2nd stage of labour - emergency delivery; ED Mx of 3rd stage of labour - delivery of placenta;

• 0.13-0.2% of vaginal deliveries
• due to shoulders being in AP position rather than oblique when head delivers

• fetal macrosomia (BW > 4000g)
• maternal obesity
• materal diabetes
• post-date pregnancies
• pelvic abnormalities
• mid-pelvic delivery
• labor abnormalities incl. protracted labor & prolonged 2nd stage
• NB. most cannot be predicted!

• prolonged 2nd stage ⇒ fetal hypoxia, poor Apgars, seizures
• brachial plexus injury
• fractured clavicle or humerus
• spinal cord injury

• delivery of head is followed by:
  • “cranial recoil”
  • retraction of head onto perineum (“turtle sign”)

• avoid excessive traction on fetal head
• stop mother pushing
• check for obstructive aetiologies
• call for obstetric help as well as anaesthetic & paediatric
• fetal blood pH falls by only 0.04/min so don't panic

• cut a generous episiotomy if not already done

• have an assistant apply gentle suprapubic pressure in an attempt to dislodge the ant. fetal shoulder below the pubic bone, or directed toward lateral portion of maternal pelvis
• consider doing above with McRobert's manouvre:
  • 2 assistants deeply flex thighs in an attempt to straighten maternal lumbar & lumbosacral lordosis & displace ant. fetal shoulder by rotating PS cephalad
  • these relieve up to 85-90% of dystocias
  • Youtube video McRobert's manouvre

• place hand behind post. shoulder & rotate baby 180deg so that this shoulder now becomes anterior

• deliver posterior arm via:
  • hand placed posteriorly in vagina
  • follow fetal arm to elbow & apply pressure to cubital fossa causing elbow to flex
  • grasp fetal arm & sweep it over fetal chest to deliver it

• Zavanelli manouvre:
  • cephalic replacement followed by C.S.