Endocrine, Metabolic, and Hematologic Emergencies
Core concepts
Know the diabetic emergencies: diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS), including fluid resuscitation, insulin, and potassium management. Understand thyroid storm and myxedema coma, adrenal crisis, and the recognition of hypoglycemia as a reversible cause of altered mental status.
In hematologic emergencies, understand the approach to anemia, sickle cell crisis, and thrombotic thrombocytopenic purpura (TTP). Know the management of severe thrombocytopenia and the recognition of hemolytic transfusion reactions. Understand electrolyte emergencies, particularly hyperkalemia and hyponatremia, and their ECG and neurologic manifestations.
Traps
Questions test whether you know that potassium must be checked before insulin in DKA and that total body potassium is depleted even when serum potassium is normal or high. Another trap is missing adrenal crisis in a patient with hypotension unresponsive to fluids. Watch for hyponatremia correction that is too rapid, causing osmotic demyelination.
Worked example / rule of thumb
A patient with DKA and potassium of 3.0 mEq/L: hold insulin and replace potassium first. Rule of thumb: "Fluids first in DKA/HHS, potassium before insulin, and never correct sodium too fast."