Umbilical Cord Prolapse

Umbilical cord prolapse is descent of the cord alongside or in front of the presenting part after rupture of membranes, with the cord lying in the vagina or outside the vulva. It is an obstetric emergency because compression of the cord cuts off fetal oxygen supply within minutes. Perinatal mortality is high without rapid delivery.

• Risk factors: malpresentation (breech, transverse lie), preterm birth, polyhydramnios, multiple pregnancy, long cord, high or unengaged head, artificial rupture of membranes, external cephalic version, multiparity.
• Occult prolapse is the cord alongside the presenting part without being palpable.
• Time from diagnosis to delivery decides the outcome.

Women have sudden rupture of membranes followed by a pulsating cord felt in the vagina or seen at the vulva, with fetal bradycardia or variable decelerations. Some have only an abnormal tracing after rupture.

• Palpable pulsatile cord on vaginal examination.
• Fetal heart rate falls with contractions or after examination.
• Differential diagnosis: cord presentation, vasa previa, placental abruption, uterine rupture, fetal distress of other cause, vaginal bleeding from other source.
• Complications: fetal hypoxia, hypoxic ischaemic encephalopathy, cerebral palsy, fetal death, neonatal death, emergency caesarean section, maternal sepsis.

The diagnosis is clinical and rapid, and a vaginal examination is done at once after any rupture with an abnormal tracing or unengaged presenting part.

• Vaginal examination: cord felt below or beside the presenting part, with or without pulsation (pulsation shows viability).
• Cardiotocography for bradycardia or variable decelerations; ultrasound only when time allows.
• Presentation, cervical dilatation, station and liquor colour.
• Do not delay delivery for investigation.

The principle is to relieve cord pressure and deliver by the quickest safe route, with a decision to delivery interval as short as possible.

• Supportive: call for senior obstetric, anaesthetic and neonatal help; push the presenting part upward with two fingers in the vagina and keep them there until delivery; knee chest or exaggerated left lateral head down position; avoid handling the cord, and keep a cord outside the vulva warm and moist in a saline soaked swab; oxygen 10 L/minute; two cannulae; fill the bladder with 500 to 750 mL sodium chloride 0.9 percent through a catheter and clamp it; urinary catheter emptied only at delivery.
• Pharmacological: terbutaline 0.25 mg subcutaneous once to reduce contractions; cefazolin 2 g IV before caesarean section; Ringer's lactate 500 to 1000 mL IV over 15 minutes; general anaesthesia unless a working epidural or spinal can be given at once; oxytocin 10 IU IM at birth; newborn resuscitation with adrenaline 0.01 to 0.03 mg/kg IV (0.1 to 0.3 mL/kg of 1 in 10,000) if heart rate stays below 60 per minute after 30 seconds of effective ventilation and compressions.
• Procedures: category 1 caesarean section aiming for delivery within 30 minutes of the diagnosis, and as fast as possible when there is bradycardia; assisted vaginal delivery by vacuum, forceps or breech extraction if fully dilated and delivery is faster than caesarean section; manual replacement of the cord is not used; neonatal bag and mask ventilation with 5 inflation breaths then 30 to 60 breaths per minute, with chest compressions in a ratio of 3 to 1 if the heart rate stays below 60 per minute.
• Special groups: preterm fetuses before 24 weeks have the decision to deliver made after counselling; women at home or in a primary facility need transfer in the knee chest position with the presenting part held up, and a catheter with the bladder filled.
• Red flags: bradycardia below 100 beats per minute, absent cord pulsation, thick meconium, maternal collapse, prolonged decision to delivery interval.
• Follow-up: umbilical cord blood gas; newborn Apgar score and neurological examination; observation for neonatal encephalopathy over 72 hours; maternal debrief and review at 6 weeks.