Operative hysteroscopy — structured oral station (12 minutes)

Opening prompt — "Tell me your plan for the medium and the energy."

Model response — say it in this order: ^[1][2]

• "I will use a bipolar resectoscope with normal saline as the medium. Bipolar requires an electrolyte-rich medium to complete its circuit, and saline avoids the hyponatraemia risk of an electrolyte-free hypotonic medium like glycine."
• "If I chose monopolar instead, I would have to switch to glycine, because monopolar current disperses in an electrolyte medium — and I would then watch the deficit to the 1000 mL hypotonic threshold."^[2]
• "I set a fluid-management system to deliver saline at the lowest pressure that allows vision, and I pre-set a stop at 2500 mL of deficit in a healthy woman, lower if she were comorbid."^[4]

Examiner is listening for: the medium-energy match stated before the scope is picked up, and a named deficit stop point. ^[1]

Probe 1 — "The deficit is now 1100 mL and climbing. The anaesthetist mentions the sodium is low. What is happening?"

• "This is fluid absorption — the operative hysteroscopy intravascular absorption syndrome. With a hypotonic medium it presents as hyponatraemia and cerebral oedema; the headache and the falling sodium fit."^[3]
• "I stop the procedure, send an urgent sodium, restrict free water, and watch for cerebral oedema. For severe symptomatic hyponatraemia with neurology I would use hypertonic saline with neurology input, correcting slowly to avoid osmotic demyelination."^[3]
• "If she had been on saline, the same deficit would mean volume overload rather than hyponatraemia — the medium tells me which."^[4]

Probe 2 — "She suddenly desaturates and collapses. End-tidal CO2 has fallen."

• "That is a gas embolism if CO2 is in use, or a pulmonary embolus to consider. For suspected gas embolism I stop insufflation, flood the field, go to Durant's position — left lateral head-down — give 100 percent oxygen, and aspirate air via a central line if in place."^[4]
• "I prevent it by using fluid media and priming the tubing to remove air before I start."^[4]

Probe 3 — "You perforate the uterus with the resectoscope loop in place. What now?"

• "That is a high-stakes perforation with energy in situ — it may have injured bowel or the broad-ligament vessels. I withdraw the instrument, stop the procedure, and take her to laparoscopy to inspect, not observe."^[4]
• "If it had been a blunt dilator in a stable patient with low suspicion, I would observe with strict pain, bleeding and fever precautions instead — the mechanism decides the management."^[4]

Probe 4 — "She asks, before you list her, why she can't just have this in the office."

This is a scored domain, not a courtesy. Demonstrate it out loud: ^[5]

• "Office hysteroscopy is genuinely a good option for many women — in trials patients prefer it, it avoids a general anaesthetic, and there is no difference in treatment success versus the operating room."
• "For your polyp we would weigh the size and how deep it sits, your preference, your other health problems, and whether I have the equipment and team to finish it safely in the office."
• "If we plan the office and it is not safe or comfortable, we stop and complete it in theatre — you stay in control."^[5]

Probe 5 — "What are the safety points for office hysteroscopy specifically?"

• Routine prophylactic antibiotics are not needed for hysteroscopy.^[4]
• The vaginoscopic no-touch entry reduces pain and is the preferred office technique.^[4]
• Watch for vasovagal syncope (about 0.2 to 1.9 percent): stop, Trendelenburg, reduce the intrauterine pressure, reassess ABCs, and refer if it persists.^[4]