A woman is being treated for preterm labor with magnesium sulfate. Which finding by the nurse indicates magnesium sulfate toxicity?
Select one:

Choice A Reason: "You would have seen more symptoms if you had been looking more closely at your baby." This is an inappropriate response that blames the parents for missing the signs of sepsis and does not explain the Reason for the subtle symptoms.

Choice B Reason: "A newborn's immune system isn't mature, so symptoms are subtle and can be hard to recognize." This is an appropriate response that educates the parents about the immunological basis of sepsis in newborns and reassures them that they are not at fault for not noticing the symptoms.

Choice C Reason: "A high fever will always be present in sick newborns, including your baby." This is an incorrect response that contradicts the fact that newborns may not develop fever in response to infection due to their immature immune systems.

Choice D Reason: "A mother's immunity usually protects the infant from illness, but not in this case." This is an inaccurate response that implies that the mother failed to provide adequate immunity to her baby and does not address the question of why the baby did not seem very ill.

Choice A Reason: Physiologic anemia due to maternal increased plasma volume. This is an incorrect answer that refers to a different condition that affects hemoglobin levels, not blood pressure. Physiologic anemia is a condition where the maternal plasma volume increases more than the red blood cell mass during pregnancy, which dilutes the hemoglobin concentration and lowers the hematocrit value. Physiologic anemia does not cause significant symptoms or complications in pregnant women, as it is an adaptive mechanism that enhances oxygen delivery and prevents fluid overload.

Choice B Reason: Pressure of the gravid uterus on the maternal inferior vena cava and aorta. This is because this statement explains the cause of supine hypotensive syndrome, which is a condition where lying flat on the back causes compression of the major blood vessels by the gravid uterus, which reduces venous return and cardiac output, which lowers blood pressure and perfusion to vital organs. Supine hypotensive syndrome can cause symptoms such as dizziness, lightheadedness, nausea, pallor, or syncope in pregnant women, especially in the third trimester.

Choice C Reason: Pressure of the presenting fetal part on the maternal diaphragm. This is an incorrect answer that indicates a different condition that affects respiratory function, not blood pressure. Pressure of the presenting fetal part on the maternal diaphragm is a result of cephalic engagement or lightening, which occurs when the fetal head descends into the pelvis and occupies more space in the abdominal cavity. Pressure of the presenting fetal part on the maternal diaphragm can cause symptoms such as dyspnea, heartburn, or rib pain in pregnant women.

Choice D Reason: A 50% increase in maternal blood volume during pregnancy. This is an incorrect answer that describes a normal physiological change that occurs during pregnancy, not a cause of supine hypotensive syndrome. A 50% increase in maternal blood volume during pregnancy is due to increased production of plasma and red blood cells, which helps meet the increased oxygen and nutrient demands of the fetus and placenta, and prepares the mother for blood loss during delivery. A 50% increase in maternal blood volume during pregnancy does not cause hypotension or dizziness in pregnant women.