The nurse is caring for a client with a history of Parkinson’s disease. Which intervention should the nurse prioritize?

Choice A reason: Platelet count assesses bleeding risk but does not measure warfarin’s anticoagulant effect. Warfarin inhibits clotting factors, monitored by INR. Platelet counts are relevant for antiplatelet drugs, not anticoagulants, making INR the priority for evaluating warfarin efficacy in atrial fibrillation.

Choice B reason: INR measures warfarin’s anticoagulant effect by assessing prothrombin time, reflecting vitamin K-dependent clotting factor inhibition. In atrial fibrillation, therapeutic INR (2.0–3.0) prevents thromboembolism. Monitoring INR ensures effective anticoagulation, making it the critical lab value for warfarin therapy management.

Choice C reason: Hemoglobin level detects bleeding, a warfarin side effect, but does not assess its therapeutic effect. INR directly evaluates anticoagulation, ensuring stroke prevention in atrial fibrillation. Hemoglobin is secondary, monitored for complications, not efficacy, making INR the priority lab value.

Choice D reason: Serum potassium is unrelated to warfarin’s anticoagulant action. Electrolyte imbalances may affect cardiac rhythm in atrial fibrillation, but INR measures warfarin’s effect on clotting factors, ensuring therapeutic anticoagulation, making it the essential value to monitor for medication efficacy.

Choice A reason: A foreign body in the eye may cause irritation or damage but is not a contraindication for ketorolac, a nonsteroidal anti-inflammatory drug (NSAID) used for pain and inflammation. The nurse would ensure removal of the foreign body first, but ketorolac can be used post-removal if indicated.

Choice B reason: Radiation exposure, such as from UV light, may cause photokeratitis but is not a specific contraindication for ophthalmic ketorolac. The medication reduces inflammation and pain, which may be beneficial in such cases. The nurse should assess for other ocular conditions, but radiation exposure alone does not preclude its use.

Choice C reason: Chemical burns require immediate irrigation and specific treatments based on the chemical involved. Ketorolac may reduce pain and inflammation post-irrigation, but it is not contraindicated. The nurse should prioritize burn management, but chemical burns do not inherently prohibit ketorolac use compared to corneal abrasions.

Choice D reason: Corneal abrasions are a contraindication for ophthalmic ketorolac, as NSAIDs can delay corneal healing and increase the risk of complications like corneal ulceration. The nurse must review the medical record to confirm the absence of abrasions, as ketorolac is typically used for postoperative pain, not traumatic corneal injuries.