A nurse is admitting a client who is at 38 weeks of gestation following a spontaneous rupture of membranes. The nurse performs a vaginal examination and palpates the umbilical cord. Which of the following actions should the nurse take?

The correct answer is choice c. One acceleration of the FHR within a 20-min period.

Here's the rationale for each choice:

Choice A: Rationale: A non-stress test (NST) is supposed to assess fetal well-being by looking for accelerations in the fetal heart rate (FHR) in response to fetal movement. An FHR that peaks 20 beats above the baseline is a desirable finding in an NST, indicating good fetal reactivity.

Choice B: Rationale: While not typical during a standard NST, three uterine contractions within a 20-minute period might not necessarily require immediate intervention. However, the nurse should document it and notify the healthcare provider for further assessment, especially if the contractions are causing discomfort or if there are other concerning signs.

Choice C: Rationale: A single acceleration of the FHR within a 20-minute NST is considered non-reactive and may indicate fetal compromise. This finding requires further investigation by the healthcare provider, potentially including additional monitoring or interventions.

Choice D: Rationale: Uterine contractions lasting 20 to 30 seconds each are not a typical finding during an NST, but they may not necessarily be a cause for immediate concern unless they are causing the client pain or are accompanied by other concerning signs. The nurse should document the contractions and notify the healthcare provider.

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.