Medicine and Allied Specialties: Acute Presentations
Medicine questions cluster around time-critical decisions: acute coronary syndrome, stroke thrombolysis, diabetic emergencies, thyroid disease, sodium disorders and sepsis. Dermatology, psychiatry and paediatrics contribute pattern recognition and drug safety points.
Core rules
- STEMI: primary PCI if achievable within 120 minutes of first medical contact; otherwise fibrinolysis within 12 hours of symptom onset.
- Ischaemic stroke: intravenous alteplase within 4.5 hours; mechanical thrombectomy up to 24 hours in selected large-vessel occlusion.
- Diabetic ketoacidosis: isotonic fluid first, insulin 0.1 U/kg/h, and do not start insulin until potassium exceeds 3.3 mEq/L.
- Thyroid storm: thionamide first, iodine at least one hour later, plus beta-blocker and steroid.
Worked example
A young man presents with confusion and seizures; sodium is 118 mEq/L. This is symptomatic hyponatraemia and needs 3 percent saline, 100 mL over 10 minutes, repeated up to three times until seizures stop. The aim is a 4-6 mEq/L rise, then stop active correction. Total correction should not exceed 8-10 mEq/L in 24 hours because of osmotic demyelination risk, which is highest in chronic hyponatraemia, malnutrition and alcohol use.
Traps
- Giving nitrates in an inferior STEMI with right ventricular infarction and hypotension.
- Continuing metformin around iodinated contrast without checking renal function.
- Giving iodine before a thionamide in thyroid storm, which fuels hormone synthesis.