A nurse is caring for a client who is at 22 weeks of gestation and has been unable to control her gestational diabetes mellitus with diet and exercise. The nurse should anticipate a prescription from the provider for which of the following medications for the client?

Choice A reason: To call for an immediate magnesium sulfate level is not the immediate action that the nurse should take, as it is a diagnostic test that requires a blood sample and a laboratory analysis, which can take time and delay the treatment. The nurse should first stop the infusion and notify the provider, as the client is showing signs of magnesium sulfate toxicity, which is a life-threatening condition that can cause respiratory depression, cardiac arrest, or coma.

Choice B reason: To prepare to administer hydralazine is not the immediate action that the nurse should take, as it is a pharmacological intervention that requires a prescription and an assessment of the blood pressure and the fetal status. Hydralazine is an antihypertensive drug that lowers the blood pressure and prevents the complications of severe preeclampsia, such as eclampsia, stroke, or organ damage. However, the client's blood pressure is not very high and is not the main problem at the moment.

Choice C reason: To discontinue the magnesium sulfate infusion is the immediate action that the nurse should take, as it is the first and most important intervention that can reverse the effects of magnesium sulfate and restore the neuromuscular function and the respiratory rate. Magnesium sulfate is a drug that prevents seizures and lowers the blood pressure in clients with severe preeclampsia, but it can also cause toxicity if the dose is too high or the infusion is too fast.

Choice D reason: To administer oxygen is not the immediate action that the nurse should take, as it is a supportive intervention that improves the oxygen delivery to the tissues and organs, but does not address the underlying cause of the respiratory depression, which is the magnesium sulfate toxicity. The nurse should administer oxygen only after stopping the infusion and assessing the oxygen saturation and the respiratory status.

Choice A reason: This statement is incorrect, as surfactant is not an antibiotic and does not treat infections. Surfactant is a substance that is naturally produced by the lungs to reduce the surface tension and prevent the alveoli from collapsing. Premature infants may have insufficient surfactant, which can cause RDS.

Choice B reason: This statement is partially true, as surfactant can help reduce episodes of periodic apnea, which is a condition where the newborn stops breathing for more than 20 seconds. However, this is not the main purpose of surfactant therapy, and other interventions, such as oxygen, ventilation, and caffeine, may be needed to treat apnea.

Choice C reason: This statement is correct, as surfactant improves the ability of the baby's lungs to exchange oxygen and carbon dioxide, which are essential for life. Surfactant therapy can improve the lung function, reduce the need for mechanical ventilation, and prevent complications, such as bronchopulmonary dysplasia and pulmonary hemorrhage.

Choice D reason: This statement is false, as surfactant does not affect the level of sedation in the newborn. Surfactant is administered through an endotracheal tube, which may require sedation to reduce discomfort and agitation. The nurse should monitor the newborn's vital signs, oxygen saturation, and pain level during and after the procedure.