Cord prolapse

Question 1

Definition

Answer 1

The descent of the umbilical cord through the cervix alongside or past the presenting foetal part in the presence of ruptured membranes.

Question 2

Obstetric emergency complications

Answer 2

• Cord compression
• Umbilical artery vasospasm preventing venous artery blood flow to and from the foetus leading to birth asphyxia.

Question 3

Epidemiology and risk factors

Answer 3

• Multiparity
• Low birth weight (<2.5kg)
• Preterm labour (<37weeks)
• Foetal congenital abnormalities
• Breech presentation:
• Transverse, oblique or unstable lie: leaving space below the foetus which can then be occupied by the cord
• Second twin
• Polyhydramnios: more space around the foetus and below the presenting part
• Unengaged presenting part
• Low-lying placenta
• Preterm, prelabour rupture of membranes

Question 4

Procedure-related risk factors

Answer 4

• Artificial rupture of membranes (ARM) with high presenting part
• Vaginal manipulation of foetus with ruptured membranes
• External cephalic version (ECV)
• Internal podalic version
• Stabilising induction of labour
• Insertion of intrauterine pressure transducer
• Large balloon catheter induction of labour

Question 5

How can obstetric procedures lead to cord prolapse?

Answer 5

By preventing close application of the presenting part of foetus to the lower part of the uterus leaving a gap for the cord to prolapse into.

Question 6

Signs

Answer 6

• Cord seen in vagina
• Abnormal foetal heart rate pattern
• There may be no clinical Sx and a normal foetal heart rate pattern

Question 7

Symptoms

Answer 7

• Cord felt in the vagina

Question 8

Diagnosis

Answer 8

• FIRST LINE = Vaginal/speculum examination allows visualisation of the prolapsed cord. Should be excluded at every vaginal examination in labour and after SROM if RF present.
• Foetal heart auscultation
• Cardiotocography: abnormal foetal heart rate, although non-specific, a sign of cord prolapse.

Question 9

Antenatal screening

Answer 9

Routine antenatal USS: for the identification of cord presentation is not recommended.
- USS screening considered in women with breech presentation at term who are considering vaginal delivery

Question 10

Pre-delivery Treatment

Answer 10

Requires immediate delivery of the foetus:
Pre-delivery =
- Minimal handling of loops of cord lying outside the vaginal: manual replacement of the cord above the presenting part is not recommended. Handling of the cord may lead to vasospasm and hypoxic acidosis.
Elevate presenting foetal parting: manually or by filling the urinary bladder, to prevent umbilical cord compression
Mother asked to go knee-chest position (AKA ‘all fours’) to prevent cord compression until preparations for an immediate caesarian section
= left lateral position: alternative position
Tocolysis: administer if there are persistent heart rate abnormalities whilst preparing for delivery of the foetus.

Question 11

Delivery Treatment

Answer 11

Cesarean section: if vaginal delivery is not imminent
- Category 1 (delivery within 30 minutes): cord prolapse + suspicious/pathological foetal heart rate pattern and if maternal safety is not compromised.
- Category 2 (delivery within 75 minutes): if foetal heart rate pattern remains normal, continuous CTG monitoring is required and if the CTG becomes abnormal, conduct a category 1 section.
- Vaginal: normal operative (foreceps or vacuum extraction) if fully dilated and birth can be accomplished quickly and safely.

Question 12

Post-delivery

Answer 12

Paired cord blood samples: for pH and base excess measurements to provide objective measurement of foetal metabolic condition at the time of birth

Question 13

Community treatment

Answer 13

• Knee-chest face-down position
• Elevate presenting foetal part
• Emergency transfer to nearest consultant led-unit

Question 14

Complications maternal related

Answer 14

C-section:
- longer hospital stay
- higher rate of peripartum hysterectomy and maternal death, increased risk of placenta accreta and uterine rupture in future pregnancies compared with vaginal birth.
- Operative vaginal delivery: perineal and vaginal trauma.

Question 15

Foetal complications

Answer 15

complications are related to the time interval between cord prolapse and delivery:
- Low Apgar scores: babies with low Apgar scores at delivery are more likely to require resuscitation
- Birth asphyxia: from lack of O2 to the foetus
- Hypoxic brain injury: irreversible damage to the brain due to lack of oxygen supply
- Cerebral palsy
- Perinatal death