ATI LPN
Medical Surgical Endocrine ATI Questions
Question 1 of 5
A 63-year-old man is in stable condition after an acute myocardial infarction when he became hypotensive for 3 hours before paramedical personnel arrived. Over the next week, the serum urea nitrogen level increases to 48 mg/dL, the serum creatinine level increases to 5 mg/dL, and the urine output decreases. He undergoes hemodialysis for the next 2 weeks and then develops marked polyuria, with urine output of 2 to 3 L/day. His renal function gradually returns to normal. Release of which of the following substances most likely participated in the elevation of BUN, creatinine, and reduced urinary output?
Correct Answer: B
Rationale: The most common cause of acute tubular necrosis is ischemic injury. The hypotension that develops after myocardial infarction causes decreased renal blood flow, with intrarenal vasoconstriction. Sublethal endothelial injury from reduced renal blood flow leads to the increased release of the vasoconstrictor endothelin and diminished amounts of the vasodilators nitric oxide and prostaglandin. The ischemic form of acute tubular injury is often accompanied by rupture of the basement membrane (tubulorrhexis). An initiating phase that lasts approximately 1 day is followed by a maintenance phase during which progressive oliguria and increasing blood urea nitrogen levels occur, with salt and water overload. This is followed by a recovery phase, during which there is a steady increase in urinary output and hypokalemia.
Question 2 of 5
A 19-year-old, previously healthy woman collapsed after complaining of a mild sore throat the previous day. On examination she is hypotensive and febrile with purpuric skin lesions. Her peripheral blood smear shows schistocytes. Imaging studies show her adrenal glands are enlarged, and there are extensive bilateral cortical hemorrhages. Infection with which of the following organisms best accounts for these findings?
Correct Answer: D
Rationale: This is the typical adrenal finding in Waterhouse-Friderichsen syndrome, and meningococcemia is the most likely cause of such a rapid course. Chronic adrenocortical insufficiency can result from disseminated tuberculosis and from fungal infections, such as histoplasmosis, that involve the adrenal glands.
Question 3 of 5
Which of the following is not an effect of a hormone secreted by the adrenal gland?
Correct Answer: D
Rationale: Adrenal hormones (cortisol, epinephrine) raise glucose, mimic SNS, reduce inflammation; thirst is regulated by hypothalamus/ADH, not adrenal.
Question 4 of 5
Which of the following is a valve that contains 2 cusps and allows blood to flow into a ventricle?
Correct Answer: D
Rationale: Mitral (bicuspid) valve has 2 cusps, allows flow from left atrium to ventricle.
Question 5 of 5
Which of the following can increase blood flow?
Correct Answer: A
Rationale: Larger diameter reduces resistance (F = P/R), increasing flow; others impede it.