Final answer:
The symptoms of anaphylaxis during IVIG infusion include a drop in blood pressure, changes in heart rate, shortness of breath, and swelling of the tongue and throat, and should be treated immediately with epinephrine.
Step-by-step explanation:
The symptoms that would indicate to the nurse that anaphylaxis is occurring during an IV immunoglobulin (IVIG) infusion include a severe drop in blood pressure, changes in heart rate, shortness of breath, and swelling of the tongue and throat. These symptoms are a consequence of a systemic and potentially life-threatening type I hypersensitivity reaction, which can lead to anaphylactic shock if not treated promptly. The immediate administration of epinephrine is crucial as it helps to increase blood pressure, improve breathing by relaxing smooth muscles in the lungs, control heart rate, and reduce swelling.