The healthcare provider orders Lasix 40 mg IV now. The concentration available is Lasix 20 mg/mL. How many mL will the patient receive?

Choice A reason: Decreased blood pressure triggers the baroreceptor reflex, increasing sympathetic activity to raise heart rate and vasoconstriction to restore pressure. A decreased heart rate would occur with increased blood pressure, not hypotension, as parasympathetic activation dominates. This choice is incorrect as it opposes the body’s compensatory response to low blood pressure.

Choice B reason: Erythema, or skin redness, results from vasodilation or inflammation, not directly from hypotension. While compensatory vasoconstriction occurs in hypotension, it reduces skin perfusion, potentially causing pallor, not erythema. This manifestation is unrelated to the cardiovascular response to decreased blood pressure, making this choice incorrect.

Choice C reason: Increased temperature is not a direct response to decreased blood pressure. Hypotension triggers sympathetic activation, prioritizing heart rate and vasoconstriction to maintain perfusion. Temperature changes may occur in shock states, but they’re not primary manifestations of routine hypotension, making this choice irrelevant to the expected clinical response.

Choice D reason: Decreased blood pressure activates the baroreceptor reflex, stimulating sympathetic nervous system activity. This increases heart rate (tachycardia) to enhance cardiac output, compensating for low pressure to maintain tissue perfusion. This is a primary physiological response to hypotension, making it the correct clinical manifestation expected in this scenario.

Choice A reason: ACE inhibitors cause dry cough by inhibiting bradykinin breakdown, which accumulates and irritates the airways. ARBs block angiotensin II receptors without affecting bradykinin, eliminating this side effect. This makes ARBs a suitable alternative for patients experiencing cough, confirming this as the correct choice.

Choice B reason: Hyperkalemia occurs with both ACE inhibitors and ARBs due to reduced aldosterone production, which decreases potassium excretion. Both drug classes affect the renin-angiotensin-aldosterone system similarly, so switching to an ARB does not eliminate this risk, making this choice incorrect for the question.

Choice C reason: Hypotension is a shared side effect of ACE inhibitors and ARBs, as both reduce blood pressure by inhibiting the renin-angiotensin system. ARBs block angiotensin II receptors, causing vasodilation similar to ACE inhibitors, so this side effect persists, making this choice incorrect.

Choice D reason: Angioedema, though rare, can occur with both ACE inhibitors and ARBs. While less common with ARBs, it’s not eliminated, as it may result from mechanisms beyond bradykinin accumulation. Switching to an ARB doesn’t guarantee avoidance of angioedema, making this choice incorrect.