ATI Pathophysiology Exam 1

Correct Answer: A

Rationale: Mifepristone (RU-486) functions by inhibiting the action of progesterone, a hormone crucial for maintaining pregnancy. By blocking progesterone, mifepristone disrupts the uterine environment necessary for pregnancy continuation, ultimately leading to termination. Choice B is incorrect because mifepristone does not increase estrogen levels; instead, it acts on progesterone. Choice C is incorrect as mifepristone's mechanism does not involve altering the uterine lining to prevent implantation. Choice D is incorrect because mifepristone does not directly stimulate uterine contractions; its primary action is through progesterone inhibition.

Correct Answer: A

Rationale: The correct answer is A. Secondary brain injury occurs due to the body's response to the initial trauma, which can worsen the effects of the primary injury. This response includes processes like inflammation, increased intracranial pressure, and reduced oxygen delivery to tissues. Choice B is incorrect because it refers to the primary trauma itself, not the secondary injury. Choice C is incorrect as it relates to injury caused by medical interventions rather than the body's response. Choice D is incorrect as it specifically mentions focal areas of bleeding, which is a consequence of trauma rather than the cause of secondary brain injury.

Correct Answer: B

Rationale: The correct answer is B: 'Use of nitrates.' Tadalafil (Cialis) is contraindicated in patients taking nitrates due to the risk of severe hypotension. Nitrates and Cialis both cause vasodilation, which can lead to a dangerous drop in blood pressure when used together. Choices A, C, and D are incorrect because a history of hypertension, use of antihypertensive medications, and a history of peptic ulcer disease are not specific contraindications for tadalafil use.

Correct Answer: C

Rationale: The correct answer is C: Air trapping in the alveoli. A barrel chest in emphysema results from the hyperinflation of the lungs due to air trapping in the alveoli. This leads to increased anteroposterior diameter of the chest. Choices A, B, and D are incorrect. Peripheral edema is swelling caused by fluid retention in tissues, not associated with a barrel chest in emphysema. Bacterial infections in the lungs can lead to conditions like pneumonia but do not directly cause a barrel chest. Muscle atrophy of the diaphragm could affect breathing mechanics but is not specifically linked to the development of a barrel chest in emphysema.

Correct Answer: B

Rationale: Type I diabetes is caused by the destruction of the beta cells in the pancreas, leading to an inability to produce insulin. This results in a lack of insulin, leading to hyperglycemia. Choice A is incorrect as type I diabetes is characterized by a deficiency of insulin production, not overproduction. Choice C describes the pathophysiology of type 2 diabetes, where insulin receptors become less responsive to insulin. Choice D is unrelated to type I diabetes as it describes a pituitary tumor causing increased antidiuretic hormone production.