Critical care cardiology, emergencies, ethics and patient safety
This domain tests resuscitation, shock physiology and professional conduct under pressure. Ethics questions are usually concrete scenarios about consent, capacity and escalation.
Cardiogenic shock
- SCAI stages A-E; shock means hypotension, cardiac index below 2.2 L/min/m2, wedge pressure above 15 mmHg and raised lactate.
- Immediate revascularisation for ischaemic shock; norepinephrine first for pressure, dobutamine for inotropy; mechanical support considered early and reassessed frequently.
- Avoid fluid loading in pulmonary oedema.
Post-arrest and respiratory care
- Targeted temperature management 32-36 degrees Celsius for comatose survivors; avoid hyperthermia; prognosticate no earlier than 72 hours using multimodal assessment.
- Non-invasive ventilation for acute cardiogenic pulmonary oedema; intubate if failing.
- Correct potassium and magnesium before treating arrhythmia.
Emergencies
- Tamponade needs pericardiocentesis; tension pneumothorax and pulmonary embolism need immediate specific therapy; aortic dissection needs blood pressure and rate control before imaging confirmation of the extent.
Ethics and patient safety
- Informed consent requires capacity, disclosure of material risks and alternatives, and freedom from coercion. Capacity is decision-specific.
- Document do-not-resuscitate decisions, discuss escalation with family but let the patient decide when capable, and disclose errors honestly.
- High-alert medications include heparin, insulin and concentrated potassium; use checklists and structured handover.
Worked example
A 70-year-old with anterior myocardial infarction and shock after primary PCI remains hypotensive on norepinephrine. Reassess volume status, add an inotrope, consider mechanical support and document the escalation plan and goals of care.
Traps
- Fluid boluses in cardiogenic pulmonary oedema.
- Early prognostication after cardiac arrest.
- Treating a family's wishes as overriding a capable patient's refusal.