Final answer:
Out of the given options, the nurse should report to the provider immediately if the patient's knee is warm and edematous because it can indicate a serious complication like infection or deep vein thrombosis.
Step-by-step explanation:
The student has asked which finding a nurse should report immediately to the provider after assessing an older adult client who is postoperative following a right knee arthroplasty.
The findings listed are: (a) mild pain at the incision site, (b) dressing slightly saturated with serosanguineous drainage, (c) the knee is warm and edematous, and (d) the client is unable to ambulate with the assistance of a walker. Out of these options, finding (c), the client's right knee being warm and edematous, should be reported immediately.
This is because warmth and swelling can indicate a serious complication such as infection or a blood clot (deep vein thrombosis), which require immediate medical attention. Mild pain and slight serosanguineous drainage can be normal postoperative findings, and difficulty ambulating can be expected initially and managed with rehabilitation.