A woman with severe preeclampsia is being treated with bed rest and intravenous magnesium sulfate. The drug classification of this medication is

Choice A) Maternal blood type is correct because this is an essential and relevant information for the nurse to check for a woman who has had a first trimester spontaneous abortion. Spontaneous abortion, also known as miscarriage, is the loss of pregnancy before 20 weeks of gestation. It can be caused by various factors such as chromosomal abnormalities, infections, trauma, or hormonal imbalances. Maternal blood type is the classification of blood based on the presence or absence of antigens and antibodies on the red blood cells and plasma. The most common blood types are A, B, AB, and O, and each can be positive or negative for the Rh factor. Checking maternal blood type can help to identify and prevent Rh incompatibility, which is a condition that occurs when the mother has Rh-negative blood and the fetus has Rh-positive blood. This can cause the mother's immune system to produce antibodies that attack the fetal red blood cells, leading to hemolytic disease of the fetus and newborn (HDFN), which can cause anemia, jaundice, or death. To prevent this, the nurse should administer Rh immunoglobulin (RhoGAM) to the mother within 72 hours after a spontaneous abortion or any event that may cause mixing of maternal and fetal blood. Therefore, this information is vital and appropriate for the nurse to check.

Choice B) Past obstetric history is incorrect because this is not an essential or urgent information for the nurse to check for a woman who has had a first trimester spontaneous abortion. Past obstetric history is the record of previous pregnancies and their outcomes, such as number, duration, complications, or interventions. It can provide useful information for assessing the risk factors and health status of the current pregnancy. However, it does not have any immediate impact or implication for the management of a spontaneous abortion, which is a common and unpredictable event that affects about 10% to 20% of all pregnancies. Therefore, this information can be obtained later or from other sources by the nurse.

Choice C) Maternal varicella titer is incorrect because this is not a relevant or necessary information for the nurse to check for a woman who has had a first trimester spontaneous abortion. Varicella titer is a blood test that measures the level of antibodies against varicella-zoster virus (VZV), which causes chickenpox and shingles. It can indicate whether a person has immunity to VZV or needs vaccination. Checking maternal varicella titer may be important for pregnant women who have not had chickenpox or vaccination before, as VZV infection during pregnancy can cause congenital varicella syndrome (CVS), which can affect the development and function of various organs in the fetus. However, it does not relate to spontaneous abortion, which is not caused by VZV infection or immunity. Therefore, this information is irrelevant and unnecessary for the nurse to check.

Choice D) Cervical patency is incorrect because this is not a reliable or accurate information for the nurse to check for a woman who has had a first trimester spontaneous abortion. Cervical patency means how open or closed the cervix is, which can affect the progress and outcome of labor and delivery. The cervix is usually closed and firm during pregnancy, but it gradually softens, shortens, and dilates as labor approaches. Checking cervical patency can help to determine if labor has started or if there are any complications such as preterm labor or cervical incompetence.

However, it does not indicate if a spontaneous abortion has occurred or not, as the cervix may remain closed or partially open after a miscarriage. Moreover, checking cervical patency can be invasive and uncomfortable for the woman who has had a spontaneous abortion, and it may increase the risk of infection or bleeding. Therefore, this information should be checked only when indicated by the physician and with caution by the nurse.

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.