A nurse is providing teaching to a client who reports smoking 3 packs of cigarettes per day and has a prescription for nicotine gum. Which of the following instructions should the nurse include in the teaching?

C. Dehydration often leads to dryness of oral mucous membranes due to decreased saliva production. Improved hydration status should lead to moist oral mucous membranes as the client's fluid balance is restored. This is a positive sign that fluid replacement therapy is effective and the client's hydration status is improving.

A. In a dehydrated client, low fluid volume can lead to hypotension (low blood pressure). Effective IV fluid replacement should improve circulating blood volume and subsequently normalize blood pressure. Decreased blood pressure would indicate that the client's condition is improving with adequate fluid replacement. However, this is not always a definitive indicator on its own as other factors can influence blood pressure.

B. An increased heart rate may initially be observed in a dehydrated client. However, as fluid replacement corrects the volume deficit, the heart rate should normalize or decrease to baseline levels. Therefore, a decrease in heart rate would actually indicate effective treatment.

D. Thirst is a symptom of dehydration where the body signals a need for fluids. Effective IV fluid replacement should address the underlying cause of thirst by restoring fluid balance. Therefore, a decrease in excessive thirst would indicate that the client's hydration needs are being met adequately.

B. Endocarditis is an infection of the inner lining of the heart chambers and valves, usually caused by bacteria entering the bloodstream. Treatment typically involves antibiotics that can penetrate into heart tissues to eradicate the infection.

A. Kidney transplant recipients are at risk for infections, particularly from immunosuppressive therapy that reduces their ability to fight off pathogens. Metronidazole is not commonly indicated.

C. Metronidazole can rarely cause neurotoxic side effects, including seizures, particularly with high doses or prolonged use. It is not used to treat seizures, and its use should be carefully monitored in patients with a history of seizures or neurological disorders.

D. Hypokalemia is a metabolic disorder that requires correction of potassium levels through appropriate supplementation or treatment of the underlying cause. Metronidazole is used for infections and does not play a role in managing electrolyte abnormalities like hypokalemia.