A FRCS T&O station on MedMock, start to finish

Let's begin. An elderly man with severe pulmonary hypertension and right ventricular impairment needs an arthroplasty for a displaced intracapsular hip fracture. How would the risk of bone cement implantation syndrome shape your implant choice and peri-operative plan?

Good morning, I'm Mr Adeyemi, one of the final-year registrars. I'm ready whenever you'd like to begin.

The question is on the table. An elderly man, severe pulmonary hypertension, right ventricular impairment, on diuretics, displaced intracapsular hip fracture needing arthroplasty. How does the risk of bone cement implantation syndrome influence your implant choice and your peri-operative plan?

This man sits in the highest risk group for bone cement implantation syndrome, because pre-existing pulmonary hypertension, right ventricular dysfunction, diuretic use and advanced ASA grade are all recognised risk factors, and his right ventricle has very little reserve to cope with a sudden rise in pulmonary vascular resistance. NICE still recommends a cemented stem as the default, and WHiTE 5 supports that on function and periprosthetic fracture, so I wouldn't abandon cement lightly; I'd make the decision jointly with the anaesthetist before theatre, following the 2015 AAGBI, BOA and BGS safety guideline, and for someone this high risk an uncemented hemiarthroplasty is a legitimate, documented choice. Given his fitness he'd be a hemiarthroplasty rather than a total hip. If we do cement, I'd do a thorough lavage and dry the canal, use a distal plug, retrograde gun insertion with an intramedullary suction catheter, and avoid excessive pressurisation. At the WHO briefing we'd flag him as high risk, the anaesthetist would have invasive arterial monitoring and raised inspired oxygen, keep him well filled, and I'd say out loud when I'm about to cement so everyone is watching the monitors, with vasopressors drawn up and a plan for collapse agreed in advance.

Two parts of the anaesthetic plan you've mentioned interest me. If, thirty seconds after you cement and reduce, his end-tidal carbon dioxide drops and his pressure falls, what's happening physiologically in that right ventricle?

That's bone cement implantation syndrome declaring itself. Pressurising the canal and reducing the hip drive marrow fat, cement particles, air and platelet aggregates into the pulmonary circulation, and there's also mediator release, so pulmonary vascular resistance rises abruptly; the falling end-tidal CO2 reflects increased dead space and a falling cardiac output. His already failing right ventricle meets a sudden rise in afterload it can't overcome, so it dilates, and the septum shifts across and underfills the left ventricle, which drops systemic pressure. Because right coronary perfusion depends on the gap between aortic pressure and right ventricular pressure, that hypotension makes the right ventricle ischaemic and it fails further, which is the spiral that ends in arrest. On the Donaldson grading, hypotension with hypoxia is grade one or two depending on severity, and cardiovascular collapse needing CPR is grade three.

Okay. He's now in that spiral on the table. What are you and the anaesthetist actually doing, in order?

First I'd stop what I'm doing and say clearly that I think this is cement syndrome, stop any further manipulation or pressurisation, pack the wound and get the consultant anaesthetist and more hands into theatre. The anaesthetist gives a hundred percent oxygen and secures the airway if he's under a spinal, then supports systemic pressure with a vasopressor such as noradrenaline or metaraminol to restore right coronary perfusion, adding an inotrope like adrenaline if he's not responding; fluids are given cautiously in small boluses, because a dilated, failing right ventricle can be made worse by overloading it. If he arrests, we follow the standard ALS algorithm, which is usually PEA here, and I'd help turn him supine so compressions are effective, though they can be started in the lateral position if needed. Once he's stable I'd close quickly and safely, and he'd go to intensive care for echo and ongoing support, where pulmonary vasodilators such as inhaled nitric oxide might be considered by the ICU team. Afterwards I'd document the event, speak to the family openly under duty of candour, report it through Datix, and hold a team debrief.

Okay. His son asks afterwards whether cement should ever have been used in his father. What's the evidence you'd draw on to justify that decision?

I'd start by acknowledging how frightening that was for him and answer honestly. The evidence for cement is strong: NICE recommends cemented implants for hip fracture arthroplasty, and WHiTE 5, a large UK randomised trial published in 2022, showed better quality of life at four months and fewer periprosthetic fractures with a cemented hemiarthroplasty, with no difference in mortality, which fits the earlier Cochrane and registry findings of less pain and better mobility. Against that, the NPSA alert in 2009 and the 2015 AAGBI, BOA and BGS guideline recognise that cement syndrome is rare but can be fatal, and is concentrated in exactly the patients like his father with pulmonary hypertension and right heart disease. So the honest answer is that cement is the right default for most patients, and in his father the benefit had to be weighed against a genuinely higher risk. What justifies the decision is not the evidence alone but whether that risk was identified, discussed with the family beforehand as a material risk, agreed jointly with the anaesthetist, and documented, together with the mitigations we used.