Umbilical cord prolapse — structured oral station (12 minutes)

Opening prompt — "Tell me what you do from the doorway."

Model response — in this order, out loud: ^[1][2]

• "I would examine her immediately. A bradycardia in a woman with ruptured membranes and a breech presentation is a cord prolapse until my hand says otherwise."
• "In that one examination I confirm the cord and whether it is pulsating, and I assess dilatation, station and presentation — because those findings decide the mode of birth and I do not want to examine twice."
• "Then my hand stays in. I elevate the presenting part off the cord and I do not remove it until the baby is out. Somebody else pulls the emergency buzzer, somebody else phones the consultant and theatre."
• "Stop any oxytocin, tell her not to push, and get her knee-to-chest. Note the time the bradycardia started."^[1][3]

Examiner is listening for: examine first, one examination, hand in and stays in, and delegation of everything that would remove the hand. ^[1]

Probe 1 — "Why knee-to-chest rather than just tilting the bed?"

• "Because it has been measured. In a prospective transperineal ultrasound study of the manoeuvres we use, knee-chest gave the largest elevation of the presenting part — the parasagittal angle of progression fell from a median of 103.6 degrees to 80.7 degrees."^[2]
• "Bladder filling with 500 mL came next at 89.9 degrees, then 300 mL at 94.4 degrees. Filling with 100 mL, a 15-degree Trendelenburg tilt and elevating the buttocks on a wedge gave only modest effects."^[2]
• "In practice I use knee-chest at the bedside and exaggerated Sims for the trolley, because knee-chest is not a position you can transfer someone in."^[1][2]

Probe 2 — "She is 3 cm dilated with a footling breech. What is your mode of birth and how urgently?"

• "Category 1 caesarean. At 3 cm, vaginal birth is not achievable in any useful timeframe, and a footling breech is the highest-risk presentation for cord prolapse — non-vertex presentation carried an odds ratio of 4.67 in the Japanese national data."^[8]
• "The system standard is a decision-to-delivery interval of 30 minutes, and good units achieve a median of about 11 minutes. But the interval that correlates with cord pH is the bradycardia-to-delivery interval — pH falls about 0.009 units per minute, and the risk of a pH under 7 was 80% beyond 20 minutes versus 17.2% under 20 minutes."^[3][4]
• "The point of that distinction is that my hand has already started buying time. Decision-to-delivery is the metric the unit audits; bradycardia-to-delivery is the fetus's physiology."^[3][4]

Probe 3 — "The theatre is occupied for another eight minutes. What do you do?"

• "I keep the hand in and I fill the bladder so that elevation is maintained if I have to move or if my hand tires. A Foley catheter with the end of a blood giving set pushed into it, warmed normal saline, and I clamp it once 500 to 750 mL are in — that is the Green-top 50 regimen."^[2][5]
• "I would empty the bladder before the abdomen is opened. That is the step people forget."^[5]
• "I would consider acute tocolysis — Green-top 50 names terbutaline 0.25 mg, that is 250 micrograms, subcutaneously — if contractions are worsening the compression, and I would ask whether the occupied theatre can be swapped or a second theatre opened. I would not accept an eight-minute wait passively."^[1][3]
• "And I would be honest that the evidence for bladder filling is about mechanics, not outcome: in the only comparative series it did not change time to delivery or neonatal pH."^[5]

Probe 4 — "The heart rate recovers to 140. The registrar coming on suggests you stand down and reassess."

• "No. The cord is still prolapsed and the compression will recur — the recovery is because my hand is lifting the presenting part, not because the problem has resolved."^[1][3]
• "I would say that explicitly to the team, keep the hand in place and continue to birth. What can change is the category, not the destination: Green-top 50 allows a category 2 birth when the trace is normal, provided fetal assessment is continuous and we re-categorise to category 1 the moment it deteriorates. A recovered trace also makes regional anaesthesia more reasonable, in consultation with an experienced anaesthetist — and I would note that verbal consent is sufficient if this becomes a category 1."^[1][3]

Probe 5 — "She is 34+5 and terrified. She asks what is happening and whether her baby will be all right."

This is scored under rapport, respect and communication. Say the words. ^[1][7]

• Get to her eye level, use her name, and be honest without frightening her further: "The cord has slipped down in front of your baby and it is being squeezed, which is why the heartbeat dropped. My hand is holding the baby up off the cord and that has already helped."
• "We are taking you to theatre now for a caesarean, and everything is going to feel fast — that is because we planned for this, not because something has gone wrong with our plan."
• "Your baby is 34 weeks, so the neonatal team will be in the room. They will take him straight to the resuscitaire to check him and then bring you news."
• To the partner: "Someone will stay with you and bring you in as soon as we can." Then commit to a debrief.^[1][7]

Probe 6 — "What will you tell her afterwards about outcome, and about her next pregnancy?"

• "Outcomes for a prolapse diagnosed in hospital and delivered quickly are usually good. In a 20-year series of 307 cases, perinatal death occurred in 6.8% but over half of those were babies whose mothers arrived from home with ruptured membranes, and encephalopathy occurred in only 0.32%."^[7]
• "Her particular setting is relevant: in a tertiary cohort of preterm prelabour rupture managed expectantly between 22 and 33 weeks, prolapse occurred in 5.8% and was not independently associated with adverse infant outcome where emergency caesarean was always available. What drove harm was gestation under 25 weeks."^[6]
• "For the next pregnancy: cord prolapse is not itself strongly recurrent, but the things that caused it can be. I would plan for presentation, avoid amniotomy on a high head, and recommend birth in a unit with theatre access if she has an unstable lie."^[1][8]