Cord prolapse

Definition:

Cord prolapse is an obstetric emergency where the umbilical cord descends through the cervical canal ahead of the presenting part of the fetus or alongside it when the membranes have ruptured. This condition can lead to cord compression and subsequent fetal hypoxia, making it a critical situation that requires immediate intervention.

Epidemiology:

Cord prolapse is relatively rare, occurring in approximately 0.1% to 0.6% of all deliveries.
The risk is higher in pregnancies with abnormal fetal presentations (such as breech or transverse lies), multiple gestations, and those with excessive amniotic fluid (polyhydramnios).

Risk Factors:

Premature rupture of membranes
Long umbilical cord
Low birth weight or preterm fetus
Multiparity (having given birth two or more times)
Use of artificial rupture of membranes (ARM) for induction or augmentation of labour
Abnormal presentations (e.g., breech, transverse)
Multiple pregnancy (twins, triplets, etc.)
Polyhydramnios

Pathophysiology:

The prolapse of the umbilical cord occurs when the presenting part of the fetus does not fit snugly against the cervix, creating a space for the cord to slip through. Once prolapsed, the cord can become compressed between the fetus and the maternal pelvis or the walls of the vagina, reducing or completely obstructing blood flow through the cord. This leads to decreased oxygen and nutrient delivery to the fetus, potentially causing fetal distress or death if not promptly managed.

Clinical Features

Signs and Symptoms:

Sudden fetal bradycardia (slow heart rate) or variable decelerations observed on the fetal heart rate monitor following rupture of membranes
Visual or palpable identification of the umbilical cord in the vagina or protruding from the cervical os

Diagnosis

Diagnosis is primarily clinical, based on the observation of the cord in the vagina or felt on digital examination following the rupture of membranes, especially if associated with abnormal fetal heart rate patterns.

Management

Immediate Actions:

Call for help immediately; this is an obstetric emergency.
The mother should be instructed to assume the knee-chest position or a Trendelenburg position (lying on her back with her legs raised higher than her head) to relieve pressure on the cord.
Manual elevation of the presenting fetal part off the cord by a healthcare provider via a vaginal examination can reduce compression until delivery.
Oxygen administration to the mother can help increase fetal oxygenation.
Prepare for immediate delivery, most safely achieved by caesarean section. If the cervix is fully dilated and the fetal head is low in the pelvis, a vaginal delivery may be attempted under close monitoring.

Surgical Treatment:

Caesarean section is often the safest and quickest way to deliver the baby in the case of cord prolapse, especially if fetal distress is evident.

Prognosis

The outcome depends on the promptness of diagnosis and delivery. With rapid intervention, the prognosis for the fetus is generally good.
Delayed intervention may lead to fetal hypoxia, acidosis, and potentially death.