221) Answer
B. Urine concentration

Rationale
•ADH concentrates the urine by reabsorbing water in the renal tubule aquaporins.
•Sodium reabsorption and potassium excretion is the responsibility of aldosterone.v

220) Answer
A. Administering I.V. therapy


Rationale
•Administering I.V. fluids and medication is USUALLY beyond the scope of an LPN. The LPN must have special training in order to administer I.V. fluids.
•The other options are all within the scope of an LPN.

219) Answer
B. Check the PCA pump to verify that the settings are correct

Rationale
•After stabilizing the patient from opioid toxicity, the nurse should verify that the patient was receiving the correct dosage. The ordered dosage was safe for an adult patient, so the error may have been programming the PCA pump.
•Requesting that the PCA be discontinued or that the dosage be lowered is not appropriate until the nurse investigates the reason for opioid toxicity.

218) ANSWER
A) Cefoxitan (Mefoxin)

RATIONALE
A disulfiram-like effect is associated with certain drugs, including metronidazole (Flagyl). Onset is usually within 15-30 minutes of ingestion of alcohol, but can occur up to 72 hours after Flagyl has been discontinued. The reaction lasts approximately 20-30 minutes but can remain up to 24 hours. The core issue of the question is knowledge of which drugs can cause a disulfiram-like reaction when used with alcohol. Use specific nursing knowledge and the process of elimination to make a selection.

217) ANSWER
C) Sodium bicarbonate, to make the client alkalotic so the potassium will shift into the ECF

RATIONALE
Sodium bicarbonate will temporarily alkalinize the plasma, causing the potassium to move into the cells. NS is an isotonic solution, and therefore will not cause fluid or electrolyte shifting. Calcium gluconate is given to blunt the effects on the myocardium; it does not decrease the serum K level. Insulin and dextrose are given to decrease K levels by increasing K uptake at the cellular level. A critical word is acidosis. Recall that potassium is increased in acidosis to direct you to option 3, in which alkalosis is the goal of treatment.

216) ANSWER
C) Chronic impairment of brain functioning

RATIONALE
The behaviors described in this situation are characteristic of clients with dementia, which is a possible late consequence of AIDS. The nurse should understand that the occurrence of symptoms indicates progression of the AIDS illness and that care should be planned accordingly. Option 1 is incorrect because an individual can live with dementia for some time before death occurs, either from AIDS or another cause. Option 2 is incorrect because the situation describes behaviors that are characteristic of the chronic progressive decline that is seen in persons with dementia. Option 4 is incorrect because the particular pattern of behaviors that is described are not particularly associated with the side effect profile of drugs used to control AIDS. Review usual progression patterns of AIDS. Recognize that the client and significant others have a right to know what is happening.

215) ANSWER
B) ST elevations

RATIONALE
ST elevations indicate immediate myocardial injury; ST depressions indicate myocardial ischemia; a Q wave forms several days after a myocardial infarction; a U wave is a sign of hypokalemia. Omit options 3 and 4 as not reflective of the acute phase of myocardial injury. Recall that ST elevations reflect injury.