NURSING OB 204 OB Exam 1 Review - Questions and Answers with Rationale.

The nurse is preparing to teach a prenatal class about fetal circulation. Which statements should be included in the teaching plan? Select all that apply. 1. "The ductus arteriosus allows blood to bypass the fetal lungs." 2. "One vein carries oxygenated blood from the placenta to the fetus." 3. "The normal fetal heart tone range is 140 to 160 beats per minute in early pregnancy." 4. "Two arteries carry deoxygenated blood and waste products away from the fetus to the placenta." 5. "Two veins carry blood that is high in carbon dioxide and other waste products away from the fetus to the placenta." Rationale: The ductus arteriosus is a unique fetal circulation structure that allows the nonfunctioning lungs to receive only a minimal amount of oxygenated blood for tissue maintenance. Oxygenated blood is transported to the fetus by one umbilical vein. The normal fetal heart tone range is considered to be 110 to 160 beats per minute. Arteries carry deoxygenated blood and waste products from the fetus, and the umbilical vein carries oxygenated blood and provides oxygen and nutrients to the fetus. Blood pumped by the embryo's heart leaves the embryo through two umbilical arteries. The nursing instructor asks the student to describe fetal circulation, specifically the ductus venosus. Which statement by the student indicates an understanding of the ductus venosus? 1. "It connects the pulmonary artery to the aorta." 2. "It is an opening between the right and left atria." 3. "It connects the umbilical vein to the inferior vena cava." 4. "It connects the umbilical artery to the inferior vena cava." Rationale: The ductus venosus connects the umbilical vein to the inferior vena cava. The foramen ovale is a temporary opening between the right and left atria. The ductus arteriosus joins the aorta and the pulmonary artery. A pregnant client tells the clinic nurse that she wants to know the sex of her baby as soon as it can be determined. The nurse informs the client that she should be able to find out the sex at 12 weeks' gestation because of which factor? 1. The appearance of the fetal external genitalia 2. The beginning of differentiation in the fetal groin 3. The fetal testes are descended into the scrotal sac 4. The internal differences in males and females become apparent