Decreased surfactant production in the preterm lung is a problem because surfactant
dilates the bronchioles, decreasing airway resistance.
provides transportation for oxygen to enter the blood supply.
keeps the alveoli open during expiration.
causes increased permeability of the alveoli.
The Correct Answer is C
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.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
Choice A: This is incorrect because preeclampsia is a condition characterized by hypertension, proteinuria, and edema that occurs after 20 weeks of gestation. It is not related to abruptio placentae, which is the premature separation of the placenta from the uterine wall. Preeclampsia does not cause petechiae or bleeding around the IV site, but it may cause headache, blurred vision, epigastric pain, or seizures.
Choice B: This is incorrect because anaphylactoid syndrome of pregnancy, also known as amniotic fluid embolism, is a rare and life-threatening complication that occurs when amniotic fluid enters the maternal circulation and triggers an allergic reaction. It is not related to abruptio placentae, but it may occur during labor, delivery, or shortly after birth. Anaphylactoid syndrome of pregnancy does not cause petechiae or bleeding around the IV site, but it may cause respiratory distress, hypotension, cardiac arrest, or disseminated intravascular coagulation.
Choice C: This is the correct answer because disseminated intravascular coagulation (DIC) is a condition in which the blood clotting system is activated abnormally, leading to excessive clot formation and consumption of clotting factors and platelets. This results in bleeding from various sites, such as the IV site, gums, nose, or vagina. DIC is a common complication of abruptio placentae, as the release of thromboplastin from the placenta triggers the clotting cascade. DIC can also cause organ failure, shock, or death if not treated promptly.
Choice D: This is incorrect because puerperal infection, also known as postpartum infection, is a bacterial infection that affects the uterus, vagina, bladder, or wound site after childbirth. It is not related to abruptio placentae, but it may occur due to prolonged labor, cesarean delivery, retained placenta, or poor hygiene. Puerperal infection does not cause petechiae or bleeding around the IV site, but it may cause fever, malaise, foul-smelling lochia, or pelvic pain.
Correct Answer is D
Explanation
Choice A) Decreased metabolic rate is incorrect because this is not a result of hypothermia in the newborn, but rather a cause of it. Metabolic rate is the speed at which the body uses energy to perform its functions. Newborns have a high metabolic rate, which helps them to maintain a normal body temperature of 36.5°C to 37.5°C (97.7°F to 99.5°F). However, some factors can lower the metabolic rate of newborns, such as prematurity, low birth weight, infection, or hypoglycemia. A low metabolic rate can make the newborn more susceptible to heat loss and hypothermia, which is a condition that occurs when the body temperature drops below 36°C (96.8°F). Therefore, this response is inaccurate and misleading.
Choice B) Decreased oxygen demands is incorrect because this is not a result of hypothermia in the newborn, but rather a consequence of it. Oxygen demand is the amount of oxygen that the body needs to function properly.
Newborns have a high oxygen demand, which helps them to support their growth and development. However, some factors can decrease the oxygen demand of newborns, such as hypothermia, sedation, or asphyxia. A low oxygen demand can impair the oxygen delivery and utilization by the tissues and organs, leading to hypoxia, acidosis, or organ failure. Therefore, this response is irrelevant and inaccurate.
Choice C) Shivering to generate heat is incorrect because this is not a result of hypothermia in the newborn, but rather a mechanism that is absent in them. Shivering is an involuntary contraction of the muscles that produces heat and raises the body temperature. It is a common response to cold exposure in adults and older children, but not in newborns. Newborns do not have the ability to shiver, as their muscles are immature and lack glycogen stores.
Instead, they rely on other methods to generate heat, such as non-shivering thermogenesis, which involves burning brown fat in certain areas of the body. Therefore, this response is irrelevant and inaccurate.
Choice D) Increased glucose demands is correct because this is a result of hypothermia in the newborn that can cause complications. Glucose demand is the amount of glucose that the body needs to produce energy and maintain its functions. Newborns have a high glucose demand, which helps them to support their metabolic rate and thermoregulation. However, some factors can increase the glucose demand of newborns, such as hypothermia, stress, or infection. A high glucose demand can deplete the glucose stores and cause hypoglycemia, which is a low level of glucose in the blood that can lead to seizures, brain damage, or death. Therefore, this response is clear and accurate.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today