Cord prolapse Flashcards
Definition
The descent of the umbilical cord through the cervix alongside or past the presenting foetal part in the presence of ruptured membranes.
Obstetric emergency complications
- Cord compression
- Umbilical artery vasospasm preventing venous artery blood flow to and from the foetus leading to birth asphyxia.
Epidemiology and risk factors
- 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
Procedure-related risk factors
- 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
How can obstetric procedures lead to cord prolapse?
By preventing close application of the presenting part to the lower part of the uterus leaving a gap for the cord to prolapse into.
Signs
- Cord seen in vagina
- Abnormal foetal heart rate pattern
- There may be no clinical Sx and a normal foetal heart rate pattern
Symptoms
- Cord felt in the vagina
Diagnosis
- FIRST LINE = 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.
Antenatal screening
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
Pre-delivery Treatment
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 in knee-chest or left lateral position: to prevent cord compression
Tocolysis: administer if there are persistent heart rate abnormalities whilst preparing for delivery of the foetus.
Delivery Treatment
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.
Post-delivery
Paired cord blood samples: for pH and base excess measurements to provide objective measurement of foetal metabolic condition at the time of birth
Community treatment
- Knee-chest face-down position
- Elevate presenting foetal part
- Emergency transfer to nearest consultant led-unit
Complications maternal related
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.
Foetal complications
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
