The client with ovarian cancer is being treated with vincristine.
The nurse monitors the client, knowing that which adverse effect is specific to this medication?

Choice A rationale

Ondansetron is a serotonin 5-HT3 receptor antagonist, which blocks serotonin's action at the chemoreceptor trigger zone and vagal afferent neurons in the gastrointestinal tract. This mechanism effectively reduces nausea and vomiting by preventing the activation of emetic pathways. Administering it as an orally disintegrating tablet (ODT) can be beneficial for patients experiencing significant nausea, as it bypasses the need for swallowing and can be absorbed quickly.

Choice B rationale

Encouraging large, high-calorie meals can exacerbate nausea and vomiting in chemotherapy patients. The gastrointestinal system is often compromised due to the cytotoxic effects of chemotherapy, leading to delayed gastric emptying and increased gastric distension, which can trigger or worsen emetic responses. Small, frequent meals are generally better tolerated to minimize gastrointestinal distress.

Choice C rationale

While ginger is sometimes anecdotally used for nausea, offering ginger ale and crackers before meals may not be universally effective and could even worsen symptoms for some patients due to the sugar content in ginger ale or the dry texture of crackers. The primary focus should be on evidence-based antiemetic pharmacotherapy to manage chemotherapy-induced nausea and vomiting.

Choice D rationale

Instructing the patient to lie down immediately after eating can worsen nausea and reflux, especially if they are experiencing delayed gastric emptying or gastroparesis, common side effects of chemotherapy. Lying flat can promote the backflow of stomach contents into the esophagus. It is generally recommended to remain upright for at least 30 minutes to an hour after meals.

Choice E rationale

Limiting fluid intake to prevent excessive hydration is an incorrect intervention. Chemotherapy patients are at risk for dehydration due to vomiting, diarrhea, and decreased oral intake. Adequate hydration is crucial for maintaining renal function, electrolyte balance, and overall well-being. Encouraging small, frequent sips of fluid is generally recommended.

Choice A rationale

Tumor lysis syndrome (TLS) involves the rapid breakdown of tumor cells, releasing their intracellular contents. This process leads to the release of intracellular potassium, resulting in hyperkalemia (increased potassium), not decreased potassium. Normal potassium levels are 3.5-5.0 mEq/L.

Choice B rationale

The release of large amounts of phosphate from lysed cells in TLS leads to hyperphosphatemia. This elevated phosphate then binds with calcium, causing calcium to precipitate out of solution, resulting in hypocalcemia (decreased calcium), not increased calcium. Normal calcium levels are 8.5-10.5 mg/dL.

Choice C rationale

The rapid breakdown of nucleic acids (DNA and RNA) from lysed tumor cells results in the excessive production of purines. These purines are then metabolized into uric acid, leading to hyperuricemia (increased uric acid), which is a hallmark of TLS. Normal uric acid levels are typically 2.4-7.0 mg/dL for men and 1.4-5.8 mg/dL for women.

Choice D rationale

As tumor cells lyse, they release intracellular phosphate into the bloodstream. This leads to a significant increase in serum phosphate levels, a condition known as hyperphosphatemia, which is characteristic of TLS. Therefore, decreased phosphate would be an incorrect finding. Normal phosphate levels are 2.5-4.5 mg/dL.