When a nurse obtains an unusually low blood pressure measurement for a client whose blood pressure is generally elevated, she considers the possibility of a problem with her technique. Which of the following sources of error should she consider as a possible cause of the low reading?

The correct answer is: a. Edema.

Choice A: Edema

Edema is swelling caused by excess fluid trapped in the body’s tissues. It is a common sign of inflammation and infection. When a wound becomes infected, the body’s immune response can cause increased fluid accumulation in the affected area, leading to noticeable swelling. This swelling is often accompanied by redness, warmth, and pain, which are classic signs of infection.

Choice B: Petechiae

Petechiae are small, red or purple spots caused by bleeding into the skin. They are not typically associated with wound infections but rather with conditions that cause bleeding or clotting disorders. Petechiae do not indicate an infection but rather a different underlying issue that may require further investigation.

Choice C: Urticaria

Urticaria, also known as hives, is a skin reaction that causes itchy welts. It is usually a result of an allergic reaction and is not a sign of wound infection. Urticaria is characterized by raised, red, itchy bumps on the skin and does not typically occur in response to an infected wound.

Choice D: Crusting over granulated tissue

Crusting over granulated tissue is a normal part of the wound healing process. Granulation tissue forms as the wound heals, and a crust or scab may develop over it to protect the new tissue underneath. This is not an indication of infection but rather a sign that the wound is progressing through the healing stages.

Choice A reason: A systemic infection would affect the entire body or multiple systems, not just the urinary tract. While a urinary tract infection can become systemic if it leads to sepsis, the scenario provided does not specify such progression.

Choice B reason: A health care-associated infection (HAI) is an infection that a patient acquires while receiving treatment for another condition within a healthcare setting. Since the infection occurred after the insertion of a urinary catheter in a hospital, it is considered an HAI.

Choice C reason: An endogenous infection originates from the host's own microbial flora. The scenario does not provide enough information to determine if the infection was caused by the client's own flora or by external sources.

Choice D reason: An exogenous infection comes from outside the body. While the urinary tract infection could be exogenous, the scenario suggests it is more likely to be health care-associated due to the timing and context of the catheter insertion.