A nurse is preparing to administer phenylephrine as a vasopressor to treat a patient for hypotension. The desired therapeutic effect of phenylephrine in this context is:

Choice A reason: CT scan with contrast is an order that the nurse should question for the client who is taking metformin for hyperglycemia. Metformin is a medication that lowers the blood glucose level by decreasing the hepatic glucose production and increasing the insulin sensitivity¹. Metformin can cause a rare but serious complication called lactic acidosis, which is a buildup of lactic acid in the blood that can cause symptoms such as weakness, nausea, vomiting, or breathing problems. CT scan with contrast involves injecting iodinated contrast material into the bloodstream, which can affect the kidney function and increase the risk of lactic acidosis in patients taking metformin. The nurse should consult with the prescriber and the pharmacist about the need to stop metformin before and after the CT scan with contrast, and to monitor the kidney function and the blood glucose level of the client.

Choice B reason: Chest X-ray 1 view is not an order that the nurse should question for the client who is taking metformin for hyperglycemia. Chest X-ray is a diagnostic test that uses a small amount of radiation to produce images of the lungs, heart, and chest wall. Chest X-ray does not involve any contrast material or affect the kidney function or the blood glucose level. The nurse should follow the standard precautions and procedures for performing a chest X-ray, such as verifying the client's identity, checking for pregnancy, removing any metal objects, and positioning the client properly.

Choice C reason: V/Q scan is not an order that the nurse should question for the client who is taking metformin for hyperglycemia. V/Q scan is a diagnostic test that measures the ventilation and perfusion of the lungs, and can detect any abnormalities such as pulmonary embolism or chronic obstructive pulmonary disease. V/Q scan involves injecting a radioactive tracer into the bloodstream and inhaling a radioactive gas, which are then detected by a special camera. V/Q scan does not affect the kidney function or the blood glucose level. The nurse should follow the standard precautions and procedures for performing a V/Q scan, such as verifying the client's identity, checking for allergies, explaining the procedure, and monitoring the vital signs.

Choice D reason: Bilateral lower extremity ultrasound is not an order that the nurse should question for the client who is taking metformin for hyperglycemia. Bilateral lower extremity ultrasound is a diagnostic test that uses sound waves to produce images of the blood vessels in the legs, and can detect any abnormalities such as deep vein thrombosis or peripheral arterial disease. Bilateral lower extremity ultrasound does not involve any contrast material or affect the kidney function or the blood glucose level. The nurse should follow the standard precautions and procedures for performing a bilateral lower extremity ultrasound, such as verifying the client's identity, explaining the procedure, and applying a gel and a probe to the legs.

Choice A reason: This is correct. Dry mouth is a common side effect of anticholinergic drugs. It occurs because anticholinergic drugs block the action of acetylcholine, a neurotransmitter that stimulates the secretion of saliva and other fluids in the body. Dry mouth can cause discomfort, bad breath, and increased risk of dental problems¹.

Choice B reason: This is incorrect. Constricted bronchioles are not a side effect of anticholinergic drugs. In fact, anticholinergic drugs can cause the opposite effect: dilated bronchioles. This is because anticholinergic drugs block the action of acetylcholine, a neurotransmitter that causes the smooth muscles of the airways to contract. Dilated bronchioles can improve breathing and reduce wheezing in people with respiratory disorders, such as asthma or COPD.

Choice C reason: This is incorrect. Increased heart rate is not a side effect of anticholinergic drugs. In fact, anticholinergic drugs can cause the opposite effect: decreased heart rate. This is because anticholinergic drugs block the action of acetylcholine, a neurotransmitter that slows down the heart rate and lowers the blood pressure. Decreased heart rate can be beneficial for people with certain heart conditions, such as atrial fibrillation or tachycardia.

Choice D reason: This is correct. Dilated pupils are a common side effect of anticholinergic drugs. It occurs because anticholinergic drugs block the action of acetylcholine, a neurotransmitter that controls the muscles of the iris, which regulate the size of the pupils. Dilated pupils can cause blurred vision, sensitivity to light, and difficulty focusing.