Which maternal condition should be considered a contraindication for the application of internal monitoring devices?

Correct Answer: A

Rationale: The correct answer is A: Unruptured membranes. Internal monitoring devices are inserted through the cervix and into the uterus, which can introduce bacteria and increase the risk of infection if the membranes are not ruptured. This can lead to serious complications for both the mother and the baby. Choice B (intravenous fluid) is incorrect because IV fluids are commonly used during labor to maintain hydration and provide necessary nutrients. Choice C (Fetus has known heart defect) is incorrect because internal monitoring devices are used to assess fetal heart rate and detect any abnormalities, making this condition a reason for monitoring rather than a contraindication. Choice D (must act quickly to improve placental blood flow and fetal oxygen supply) is incorrect because internal monitoring devices are usually used for continuous monitoring and do not require immediate intervention to be placed.

Correct Answer: B

Rationale: The correct answer is B: Variable decelerations. When the mother's membranes rupture during active labor, variable decelerations should be observed in the fetal heart rate. This is because the rupture of membranes can lead to umbilical cord compression, causing variable decelerations in the fetal heart rate pattern. Variable decelerations are characterized by abrupt and visually apparent decreases in heart rate variability. A: Early decelerations are usually associated with head compression during contractions and are benign. C: Nonperiodic accelerations are not a typical pattern seen in response to ruptured membranes during labor. D: An increase in baseline variability is a positive sign and does not specifically indicate the occurrence of variable decelerations related to umbilical cord compression.

Correct Answer: D

Rationale: The correct answer is D: Sympathetic stimulation. Sympathetic stimulation increases heart rate by releasing norepinephrine, which acts on beta-adrenergic receptors in the heart. This leads to an increase in heart rate. Choices A and B are incorrect because inhibition of epinephrine or norepinephrine would not cause an increase in heart rate. Choice C is incorrect because stimulation of the vagus nerve would actually decrease heart rate by releasing acetylcholine, which acts on muscarinic receptors in the heart.

Correct Answer: C

Rationale: The correct answer is C: Reposition to left side-lying position. This is the priority intervention because decelerations that start after the peak of the contraction and return to baseline after it ends suggest umbilical cord compression. Repositioning the patient to the left side-lying position can alleviate pressure on the cord, potentially improving fetal perfusion. Increasing IV infusion (A) may not directly address the cord compression. Elevating lower extremities (B) may not alleviate the pressure on the cord. Administering oxygen (D) may be beneficial, but repositioning the patient is the primary intervention to address the underlying issue.

Correct Answer: D

Rationale: The correct answer is D because positioning the patient in a knee-chest position helps to relieve pressure on the vena cava, improving blood flow to the placenta and fetus. This can help alleviate variable decelerations. Choice A is incorrect because administering oxygen at 8 to 10 L/min would not directly address the cause of variable decelerations. Choice B is incorrect as placing a wedge under the right hip is typically used for supine hypotension syndrome. Choice C is incorrect because increasing IV fluids may not directly address the issue of variable decelerations.