A nurse is teaching a newly licensed nurse about the uses of ultrasonography in the first trimester of pregnancy. Which of the following statements by the newly licensed nurse indicates an understanding of the teaching?

Choice A rationale:

The nurse should not tell the client that she cannot have an amniocentesis until she is at least 35 years of age. Age is not the primary factor for determining the eligibility for an amniocentesis. Amniocentesis is typically performed when there is a medical indication, such as advanced maternal age, abnormal prenatal screening, or a family history of genetic disorders.

Choice B rationale:

The nurse should not schedule the amniocentesis for later today without further clarification from the provider. Scheduling medical procedures without the provider's approval is not within the nurse's scope of practice and could lead to potential risks.

Choice C rationale:

This is the correct answer. The nurse should explain to the client that amniocentesis is a procedure used to determine if the baby has genetic or congenital disorders. It involves the extraction of a small amount of amniotic fluid to analyze the fetal cells for genetic abnormalities.

Choice D rationale:

The nurse should not tell the client that her provider will schedule a chorionic villus sampling (CVS) to determine the sex of the baby. CVS is another prenatal diagnostic test, but its primary purpose is to detect genetic disorders early in pregnancy, not to determine the baby's sex.

The correct answer is Choice C.

Choice A rationale: Thiazide diuretics cause potassium and chloride loss, leading to metabolic alkalosis, not respiratory alkalosis. Hypokalemia decreases hydrogen ion excretion, increasing bicarbonate levels. Metabolic alkalosis is characterized by pH >7.45 and HCO₃⁻ >26 mEq/L rather than decreased PaCO₂.

Choice B rationale: Vomiting leads to metabolic alkalosis due to gastric acid loss. Hydrogen ion depletion increases bicarbonate concentration, shifting pH above normal. Arterial blood gases typically show increased HCO₃⁻ (>26 mEq/L) with a compensatory increase in PaCO₂ (>45 mmHg), not respiratory alkalosis.

Choice C rationale: Salicylate intoxication initially induces hyperventilation, reducing PaCO₂ levels below 35 mmHg and increasing pH above 7.45, leading to respiratory alkalosis. As toxicity progresses, metabolic acidosis may develop due to lactic acid accumulation, but early stages primarily present with respiratory alkalosis.

Choice D rationale: Hypoventilation leads to CO₂ retention, increasing PaCO₂ above 45 mmHg, forming carbonic acid (H₂CO₃) and causing respiratory acidosis. Blood gases show pH <7.35 with elevated PaCO₂, not respiratory alkalosis, which is caused by excessive CO₂ elimination through hyperventilation.