The nurse is preparing to administer a calcium channel blocker to a client with hypertension. The nurse understands that the mechanism of action of these drugs is to
cause vasodilation and increase total peripheral resistance.
cause vasodilation and decrease total peripheral resistance.
cause vasoconstriction and decrease total peripheral resistance.
cause vasoconstriction and increase total peripheral resistance.
Number 2 is correct.
Rationale: Calcium channel blockers cause vasodilation and decrease total peripheral resistance, which leads to a decrease in blood pressure. The other options do not correctly describe the mechanism of action of calcium channel blockers. Vasoconstriction coupled with increased total peripheral resistance would raise, not lower, blood pressure. Increasing the pressure on one component results in overall blood pressure increase, even if the other component is decreased.
