Pharmacology Flashcards

Which beta-blocker is cardioselective and commonly used in EMS for rate control in atrial fibrillation?

Answer: Metoprolol

Metoprolol is a beta-1 selective (cardioselective) blocker that slows AV conduction for rate control in atrial fibrillation.

What is the primary concern when administering calcium channel blockers to a patient already on beta-blockers?

Answer: Additive hypotension and AV block

Both drug classes depress cardiac conduction and contractility; combining them greatly increases the risk of severe hypotension and complete AV block.

Sodium bicarbonate is indicated in the prehospital setting for which condition?

Answer: Tricyclic antidepressant overdose with widened QRS

Sodium bicarbonate alkalinizes the serum, which reduces sodium channel blockade from TCAs and narrows the QRS complex.

A patient experiencing anaphylaxis has received epinephrine IM. Which additional medication is typically given to block histamine receptors?

Answer: Diphenhydramine

Diphenhydramine (Benadryl) is an H1 antihistamine that blocks histamine receptors and reduces urticaria, itching, and some cardiovascular effects of anaphylaxis.

Which medication is used prehospital to treat symptomatic bradycardia unresponsive to atropine?

Answer: Dopamine or transcutaneous pacing

When atropine fails, dopamine infusion or transcutaneous pacing are the next steps for hemodynamically unstable bradycardia per ACLS guidelines.

What is the correct pediatric dose of epinephrine 1:10,000 for cardiac arrest?

Answer: 0.01 mg/kg IV/IO

The PALS recommended dose is 0.01 mg/kg (0.1 mL/kg of the 1:10,000 concentration) IV or IO for pediatric cardiac arrest.

Furosemide exerts its primary diuretic effect by acting on which part of the kidney?

Answer: Loop of Henle

Furosemide is a loop diuretic that inhibits the Na-K-2Cl cotransporter in the thick ascending limb of the loop of Henle.