Correct Answer: D

Rationale: Xerostomia, also known as dry mouth, is a common side effect of radiation therapy in the head and neck region. It occurs when the salivary glands are damaged during treatment, reducing saliva production and causing a dry sensation in the mouth. The correct answer is 'Dry mouth' (option D). Choice A, 'Cracks in the corners of the mouth,' describes angular cheilitis, a condition linked to nutritional deficiencies or candida infection. Choice B, 'Peeling skin from the tongue and gums,' is more indicative of conditions like oral thrush or mucositis. Choice C, 'Increased dental caries,' is a consequence of reduced saliva flow but does not specifically describe xerostomia.

Correct Answer: A

Rationale: The patient's complaint of sharp pain when taking a deep breath is concerning for pleurisy or pleural effusion. The nurse should auscultate breath sounds to assess for a pleural friction rub or decreased breath sounds, which could indicate these conditions. It is crucial to gather assessment data before initiating any pain medications. Asking the patient to cough forcefully may exacerbate the pain and should be avoided until further assessment. Contacting the healthcare provider should be based on the assessment findings; therefore, it is premature to notify the provider without conducting a thorough assessment first.

Correct Answer: D

Rationale: While all the values are abnormal, the low PaO2 level of 59 mm Hg indicates that the patient is at a critical point on the oxyhemoglobin dissociation curve. At this level, a small decrease in PaO2 can lead to a significant drop in oxygen saturation and compromise tissue oxygenation. Therefore, immediate intervention is necessary to improve the patient's oxygenation status. Choice A (HCO3 of 31 mEq/L) may indicate metabolic alkalosis or compensation for respiratory acidosis; however, it does not require immediate action in this scenario. Choice B (SaO2 of 92%) is slightly low but not critically low to require immediate action. Choice C (PaCO2 of 31 mm Hg) is within the normal range and does not indicate immediate danger to the patient.

Correct Answer: C

Rationale: When initiating treatment with glatiramer acetate (Copaxone), patient education should focus on teaching the patient how to draw up and administer injections of the medication. Copaxone is administered via self-injection, hence understanding the correct technique is crucial for successful treatment. Recommendations regarding fluid intake or the need to avoid driving heavy machinery are not directly related to glatiramer acetate therapy. Additionally, while discussing contraceptive methods may be important, the use of oral contraceptives does not specifically contraindicate the use of glatiramer acetate.

Correct Answer: D

Rationale: The correct answer is that the patient has an increased serum creatinine level. Dalfampridine should not be given to patients with impaired renal function as it can worsen their condition. Options A, B, and C are unrelated to the administration of dalfampridine. The fact that the patient has relapsing-remitting MS, walks for exercise, or experiences neck pain does not directly impact the decision to administer dalfampridine. However, an increased serum creatinine level is a contraindication for this medication and requires consultation with the healthcare provider to determine the appropriate course of action.