The nurse is evaluating a child who has been outside in the woods at camp. The child has multiple, small annular lesions without an indurated center on the arm. The nurse suspects Lyme disease.

Which stage of Lyme disease does the nurse believe that this child is exhibiting?

The correct answer is choice B. Epinephrine.

Choice A rationale:

Diphenhydramine. Diphenhydramine is an antihistamine commonly used to relieve allergic symptoms such as itching, rash, and runny nose. While it can be part of the treatment for anaphylactic reactions, it is not the medication of choice for immediate administration in the case of a severe anaphylactic reaction like the one described in the scenario.

Choice B rationale:

Epinephrine. Correct Answer. In cases of severe anaphylactic reactions, epinephrine (adrenaline) is the medication of choice for immediate administration. Epinephrine acts rapidly to reverse life-threatening symptoms, such as airway constriction, low blood pressure, and hives. It works by dilating airways, increasing heart rate, and improving blood pressure.

Choice C rationale:

Dopamine. Dopamine is a medication used to increase blood pressure and cardiac output in certain critical situations. However, it is not the first-line treatment for anaphylactic reactions. Epinephrine's effects on airway and cardiovascular function make it the preferred choice in this context.

Choice D rationale:

Calcium chloride. Calcium chloride is not the appropriate medication for treating anaphylactic reactions. Its main medical uses include treating hypocalcemia (low blood calcium levels) and certain cardiac arrhythmias. It does not address the primary symptoms and physiological changes associated with anaphylaxis.

The correct answer is choice C. Decreased oxygen-carrying capacity of blood.

Choice A rationale:

Anemia does not primarily result in a depressed hematopoietic system. In fact, anemia often occurs due to various factors that affect red blood cell production or lifespan. The hematopoietic system can be overactive in response to anemia, attempting to compensate for the reduced oxygen-carrying capacity of the blood.

Choice B rationale:

While some anemias may involve the presence of abnormal hemoglobin (e.g., sickle cell anemia), this is not the primary result of anemia. The primary consequence of anemia is a decreased ability of the blood to carry oxygen to the body's tissues.

Choice C rationale:

The correct choice. Anemia leads to a decreased oxygen-carrying capacity of the blood. Hemoglobin, the protein in red blood cells responsible for carrying oxygen, is reduced in quantity or function in various types of anemia. This results in inadequate oxygen delivery to tissues, potentially causing symptoms such as fatigue, weakness, pallor, and shortness of breath.

Choice D rationale:

Increased blood viscosity is not a primary result of anemia. Anemia tends to reduce blood viscosity because there are fewer red blood cells and less hemoglobin present, which makes the blood more fluid and less viscous. Increased blood viscosity is more commonly associated with conditions like polycythemia, where there is an excess of red blood cells.