Which of the following doses of dopamine (Intropin) results in stimulation of beta1 receptors and increased myocardial contractility?
a. 1 mcg/kg/min
b. 5 mcg/kg/min
c. 15 mcg/kg/min
d. 20 mcg/kg/min
B
At low dosages of 1 to 2 mcg/kg/min, dopamine stimulates dopaminergic receptors, causing renal and mesenteric vasodilation. Moderate dosages result in stimulation of beta1 receptors to increase myocardial contractility and improve cardiac output. At dosages greater than 10 mg/kg/min, dopamine predominantly stimulates alpha receptors, resulting in vasoconstriction that often negates both the beta-adrenergic and dopaminergic effects.
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Two patients on your unit have returned from right knee arthroscopies. Patient A is reporting pain of an eight to nine on a zero-to-ten pain scale. Patient B is reporting a pain level of three to four on the same pain scale
What may provide a rationale for the different perceptions of pain? A) Endorphin levels may vary between patients, affecting the perception of pain. B) One of the patients is exaggerating her sense of pain. C) The patients are likely experiencing a variance in vasoconstriction. D) One of the patients may be experiencing opiate tolerance.
Write 0.49 as a fraction in lowest terms and as a percentage
1. 49/100; 49% 2. 7/15; 49% 3. 49/100; 4.9% 4. ½; 4.9%
The nurse is preparing to discuss the use of primary hypertensive agents with a client. Which prescriptions should the nurse include?
A. Thiazide diuretics B. Angiotensin-II receptor blockers (ARBs) C. Beta-adrenergic antagonists D. Direct-acting vasodilators E. Peripheral adrenergic antagonists
A parent of a teenager being treated for anorexia nervosa asks the nurse what, "Being an enmeshed family" means. Which question provides the best response to the question?
a. "What do you think that statement means?" b. "Who told you your family was enmeshed?" c. "Are the members of your family expected to be independent and self-reliant?" d. "Does your family place importance on being successful and accepted by others?"