A nurse is caring for a client who is to receive a unit of packed RBCs. The nurse should prime the blood administration tubing using which of the following IV solutions?

Choice A reason: Bradycardia is not an adverse effect of diphenhydramine. Bradycardia is a slow heart rate, usually below 60 beats per minute. Diphenhydramine is an antihistamine that blocks the effects of histamine, a chemical that causes allergic reactions. Diphenhydramine does not affect the heart rate, although it may cause palpitations or irregular heartbeat in some cases.

Choice B reason: Constipation is an adverse effect of diphenhydramine. Constipation is a condition in which the bowel movements are infrequent, hard, or difficult to pass. Diphenhydramine has anticholinergic properties, which means it inhibits the activity of acetylcholine, a neurotransmitter that regulates the smooth muscle contraction in the gastrointestinal tract. Diphenhydramine can reduce the intestinal motility and cause constipation, as well as dry mouth, blurred vision, and urinary retention.

Choice C reason: Hypertension is not an adverse effect of diphenhydramine. Hypertension is a condition in which the blood pressure is abnormally high, usually above 140/90 mmHg. Diphenhydramine does not affect the blood pressure, although it may cause orthostatic hypotension, which is a sudden drop in blood pressure when changing positions from lying to standing. This can cause dizziness, fainting, or falls.

Choice D reason: Sedation is an adverse effect of diphenhydramine. Sedation is a state of reduced alertness, awareness, or responsiveness. Diphenhydramine can cross the blood-brain barrier and affect the central nervous system, causing drowsiness, fatigue, impaired coordination, and reduced mental performance. Diphenhydramine can also potentiate the effects of alcohol and other sedatives, such as benzodiazepines, opioids, or barbiturates. The nurse should advise the client to avoid driving, operating machinery, or performing other tasks that require attention and concentration while taking diphenhydramine.

Choice A reason: Expecting to gain weight while taking this medication is not a correct instruction, as it may discourage the client from adhering to the treatment and may worsen the hypertension. Captopril is an angiotensin-converting enzyme (ACE) inhibitor that lowers the blood pressure by preventing the formation of angiotensin II, a potent vasoconstrictor. Captopril does not cause significant weight gain, but it may cause fluid retention or edema in some cases. The nurse should advise the client to monitor the weight daily and report any sudden or excessive increase to the provider.

Choice B reason: Not using salt substitutes while taking this medication is a correct instruction, as it may prevent the risk of hyperkalemia, a potentially life-threatening condition. Captopril may increase the potassium level in the blood by reducing the secretion of aldosterone, a hormone that regulates the sodium and potassium balance. Salt substitutes may contain potassium chloride, which may further elevate the potassium level. The nurse should advise the client to avoid salt substitutes and high-potassium foods, such as bananas, oranges, or tomatoes, and to have regular blood tests to check the electrolyte levels.

Choice C reason: Counting the pulse rate before taking the medication is not a necessary instruction, as it may not reflect the effect of the medication on the blood pressure. Captopril does not affect the heart rate significantly, but it may lower the blood pressure too much, especially in the first few weeks of treatment or after a dose increase. This may cause hypotension, dizziness, or fainting. The nurse should advise the client to monitor the blood pressure regularly and report any symptoms of hypotension to the provider.

Choice D reason: Taking the medication with food is not a correct instruction, as it may reduce the absorption and effectiveness of the medication. Captopril should be taken on an empty stomach, at least one hour before or two hours after a meal, to ensure optimal bioavailability. The nurse should advise the client to take the medication at the same time every day and to avoid skipping or doubling the doses.