Which of the following indicates a possible infection post-surgery?

The presence of fever and redness at the surgical site is a strong indicator of a potential infection following a surgical procedure. Fever is a systemic response that often accompanies infection, as the body raises its temperature in an effort to fight off pathogens. Redness at the surgical site suggests localized inflammation, which can occur due to infection. This combination of symptoms is significant in the clinical assessment of a patient post-surgery, signaling the healthcare provider to investigate further and possibly initiate treatment for infection.

In contrast, decreased appetite may occur for a variety of reasons post-surgery, such as pain or nausea, but it is not specific to infection. Increased urination is typically associated with other conditions or medication effects, rather than infection. Well-formed wound edges indicate proper healing and are not a sign of infection; in fact, they suggest that the surgical site is healing as expected.