The nurse assesses a client with intermittent claudication who is receiving pentoxifylline. Which assessment should the nurse perform to determine the effectiveness of the medication?

A. Measure hourly urinary output: Pentoxifylline primarily affects blood flow by decreasing blood viscosity and improving red blood cell flexibility, enhancing peripheral circulation. Urinary output is not directly influenced by this medication and is not a reliable indicator of its effectiveness for intermittent claudication. B. Evaluate level of consciousness: While monitoring neurological status is important for many clients, changes in consciousness are not expected indicators of pentoxifylline effectiveness. The primary therapeutic target is the improvement of blood flow and reduction of pain during walking, not mental status changes. C. Monitor numeric pain scale: Pentoxifylline is used to treat intermittent claudication by improving blood flow to the limbs, reducing muscle pain during exertion. A decrease in reported pain levels on a numeric scale during walking activities is the most direct and meaningful measure of the medication’s effectiveness. D. Auscultate bowel sounds: Pentoxifylline does not have a primary effect on gastrointestinal motility or bowel function. Monitoring bowel sounds would not provide useful information about whether the drug is effectively relieving the client's symptoms of intermittent claudication.