A nurse is monitoring a client who is receiving a unit of packed red blood cells (RBCs) following surgery. Which of the following assessments is an indication that the client might be experiencing circulatory overload?

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: The nurse collects a urine specimen is an appropriate action, as it can help detect the presence of hemoglobinuria, which is a sign of hemolysis. Hemoglobinuria is the excretion of hemoglobin in the urine, which can cause the urine to appear red or brown.

Choice B reason: The nurse sends a blood specimen to the laboratory is an appropriate action, as it can help confirm the diagnosis of a hemolytic reaction and identify the cause. The laboratory can perform tests such as blood typing, cross-matching, direct antiglobulin test (DAT), and serum bilirubin.

Choice C reason: The nurse initiates an infusion of 0.9% sodium chloride is an appropriate action, as it can help maintain the client's fluid and electrolyte balance and prevent hypovolemic shock. 0.9% sodium chloride is the preferred solution for blood transfusion reactions, as it is isotonic and compatible with blood products.

Choice D reason: The nurse starts the transfusion of another unit of blood product is an inappropriate action, as it can worsen the client's condition and increase the risk of complications. The nurse should not resume the transfusion until the cause of the reaction is determined and the provider orders a new unit of blood product. The nurse should also return the unused blood product and tubing to the blood bank for analysis.