Explaining QTc risk and medicine changes after a near-syncope (CASC)

Station instructions (candidate)

You have 7 minutes. Explain why her heart-rhythm risk rose (medicines + low potassium + antibiotic), what QTc means in plain language, and the plan: correct potassium, review/stop temporary culprits (clarithromycin), adjust psychotropics thoughtfully (citalopram dose/agent and quetiapine risk context), monitor ECG, and protect her mental health with a clear follow-up. Do not promise zero risk. Do not strip all psychotropics without a plan. Do not use unexplained jargon.[1][2][3]

Marking domains

Empathy and agenda; accurate plain-language QTc/TdP risk; multi-hit model (drugs + electrolytes + antibiotic); collaborative deprescribing/switching; safety-netting for syncope; shared decision and written plan; avoids both panic and minimisation.[1][4][5]

Model communication map

1. Open: thank her for coming; name the shared goals — stay safe from collapse and keep mood/sleep protected.[5]
2. Plain QTc: "The ECG shows the recovery time of each heartbeat is longer than we like; when it gets too long, rare dangerous rhythms can cause faints."[1][4]
3. Why now: combination of mental health medicines that can stretch that interval, a heart-sensitive antibiotic, and low potassium — risk adds up rather than one villain alone.[1][2][4]
4. Immediate plan: replace potassium (and magnesium if low); stop or switch clarithromycin with the medical team; repeat ECG; monitoring if still very prolonged.[2]
5. Psychotropic plan: review citalopram dose/choice (higher-dose citalopram has more QTc signal in research) and quetiapine need/dose; change one step at a time with a covering plan for sleep and mood.[3][1][5]
6. Safety-net: if she faints, nearly faints, or has pounding irregular heartbeats — emergency care; list of medicines to show any doctor.[2]
7. Close: questions, written summary, GP/pharmacy communication, follow-up date.[5]

Common fails

• "All psychiatric drugs are dangerous — stop everything today" without a mental health plan.[5]
• Ignoring the antibiotic and low potassium and blaming only "the antidepressant."[2][4]
• Over-reassuring "QTc never matters with modern meds."[1]
• Using only acronyms (TdP, IKr, Bazett) without checking understanding.[1]