A pregnant woman at 37 weeks of gestation has had ruptured membranes for 26 hours. A cesarean section is performed for failure to progress. The fetal heart rate (FHR) before birth is 180 beats per minute with limited variability. At birth, the newborn has Apgar scores of 6 and 7 at 1 and 5 minutes and is noted to be pale and tachypneic. Based on the maternal history, what is the most likely cause of this newborn's distress?

Choice A reason: Elevated blood pressure is a hallmark sign of preeclampsia, which is a hypertensive disorder of pregnancy that can cause serious complications, such as eclampsia, HELLP syndrome, or placental abruption. The nurse should monitor the client's blood pressure regularly and report any readings above 140/90 mm Hg to the provider.

Choice B reason: Increased urine output is not a sign of preeclampsia, but rather a normal physiological change of pregnancy, as the renal blood flow and glomerular filtration rate increase. A client with preeclampsia may have decreased urine output, which can indicate renal impairment or oligohydramnios.

Choice C reason: Joint pain is not a sign of preeclampsia, but rather a common discomfort of pregnancy, as the hormones relaxin and progesterone loosen the ligaments and joints. A client with preeclampsia may have epigastric pain, which can indicate liver involvement or impending eclampsia.

Choice D reason: Vaginal discharge is not a sign of preeclampsia, but rather a normal occurrence of pregnancy, as the cervical glands secrete more mucus to protect the uterus from infection. A client with preeclampsia may have vaginal bleeding, which can indicate placental abruption or disseminated intravascular coagulation.

Choice A reason: Increased risk of anemia is not a likely cause of respiratory distress in a term macrosomic newborn, as it can affect any newborn regardless of the maternal diabetes status or the fetal size. Anemia can cause pallor, tachycardia, and poor feeding, but not respiratory distress.

Choice B reason: Hyperinsulinemia is a likely cause of respiratory distress in a term macrosomic newborn, as it results from the fetal exposure to high maternal glucose levels and the subsequent overproduction of insulin. Hyperinsulinemia can impair the synthesis of surfactant, which is a substance that prevents the alveoli from collapsing and facilitates gas exchange. Hyperinsulinemia can also cause hypoglycemia, which can affect the respiratory center and cause apnea.

Choice C reason: Increased blood viscosity is not a likely cause of respiratory distress in a term macrosomic newborn, as it can affect any newborn with polycythemia, which is an abnormally high number of red blood cells. Polycythemia can cause cyanosis, jaundice, and thrombosis, but not respiratory distress.

Choice D reason: Brachial plexus injury is not a likely cause of respiratory distress in a term macrosomic newborn, as it affects the nerves that supply the arm and hand, not the lungs. Brachial plexus injury can occur due to the excessive traction or stretching of the shoulder during delivery, and can cause weakness, paralysis, or sensory loss in the affected arm.