Which data should alert the nurse that the neonate is postmature?

Choice A) dilates the bronchioles, decreasing airway resistance: This is not the correct function of surfactant.

Surfactant is a substance that reduces the surface tension of the fluid that lines the alveoli, which are the tiny air sacs in the lungs where gas exchange occurs. Surfactant does not affect the diameter of the bronchioles, which are the small airways that branch from the bronchi. Bronchodilation and bronchoconstriction are regulated by the autonomic nervous system and various mediators, such as histamine, epinephrine, and acetylcholine.

Choice B) provides transportation for oxygen to enter the blood supply: This is not the correct function of surfactant. Surfactant does not transport oxygen or any other gas. Oxygen diffuses from the alveoli into the capillaries, where it binds to hemoglobin in the red blood cells. The red blood cells then transport oxygen to the tissues via the blood circulation. Surfactant does not play a role in this process.

Choice C) keeps the alveoli open during expiration: This is the correct function of surfactant. Surfactant prevents the alveoli from collapsing during expiration by lowering the surface tension of the fluid that lines them. This allows for easier breathing and better gas exchange. Without enough surfactant, the alveoli tend to collapse and stick together, causing atelectasis, which is a condition where some or all of a lung collapses. Atelectasis can lead to hypoxia, respiratory distress, and infection.

Choice D) causes increased permeability of the alveoli: This is not the correct function of surfactant. Surfactant does not increase or decrease the permeability of the alveoli, which is the ability of substances to pass through them.

Permeability of the alveoli depends on several factors, such as pressure gradients, solubility, molecular size, and membrane thickness. Increased permeability of the alveoli can occur in conditions such as acute respiratory distress syndrome (ARDS), where fluid leaks into the alveolar space and impairs gas exchange. Surfactant does not cause this condition, but it can be affected by it.

Choice A) Prepare for an emergency cesarean birth is incorrect because this is not a priority or appropriate action for a nurse who is caring for a client who has preeclampsia and is being treated with magnesium sulfate IV.

Preeclampsia is a condition that causes high blood pressure, proteinuria, and edema during pregnancy. It can lead to complications such as eclampsia, which is seizures, or HELLP syndrome, which is hemolysis, elevated liver enzymes, and low platelets. Magnesium sulfate is a medication that helps to prevent or treat seizures in preeclamptic clients by relaxing the muscles and nerves. However, it can also cause side effects such as respiratory depression, hypotension, or loss of reflexes. Preparing for an emergency cesarean birth may be necessary if the client has severe preeclampsia or fetal distress, but it does not address the immediate problem of magnesium toxicity. Therefore, this action should be done only when indicated by the physician and after stabilizing the client's condition.

Choice B) Discontinue the medication infusion is correct because this is a priority and appropriate action for a nurse who is caring for a client who has preeclampsia and is being treated with magnesium sulfate IV. Discontinuing the medication infusion can help to stop or reduce the adverse effects of magnesium sulfate, such as respiratory depression, hypotension, or loss of reflexes. These effects can indicate magnesium toxicity, which is a life-threatening condition that can cause cardiac arrest or coma. The nurse should also notify the physician and prepare to administer calcium gluconate, which is an antidote for magnesium toxicity. Therefore, this action should be done as soon as possible for clients who show signs of magnesium overdose.

Choice C) Place the client in Trendelenburg's position is incorrect because this is not a safe or suitable action for a nurse who is caring for a client who has preeclampsia and is being treated with magnesium sulfate IV.

Trendelenburg's position means lying on the back with the head lower than the feet. It is sometimes used to improve blood flow to the brain or heart in cases of shock or hypotension. However, it can also cause complications such as increased intracranial pressure, decreased lung expansion, aspiration, or acid reflux. Moreover, it does not help to reverse or prevent the side effects of magnesium sulfate, such as respiratory depression, hypotension, or loss of reflexes. Therefore, this action should be avoided or used with caution for clients who are receiving magnesium sulfate IV.

Choice D) Assess maternal blood glucose is incorrect because this is not a relevant or necessary action for a nurse who is caring for a client who has preeclampsia and is being treated with magnesium sulfate IV. Blood glucose is the level of sugar in the blood that provides energy to the cells. It is measured by a blood test or a finger stick test. It can be affected by various factors such as diet, exercise, medication, or pregnancy. Assessing maternal blood glucose may be important for clients who have diabetes or gestational diabetes, which are conditions that cause high blood sugar levels that can harm the mother and the baby. However, it does not relate to preeclampsia or magnesium sulfate, which are conditions that affect blood pressure and nerve function. Therefore, this action should be done only when indicated by the physician and according to the client's history and needs.