The pediatric nurse is caring for a 2-year-old with a respiratory rate of 42 breaths per minute and a FLACC score 8. Which acid-base imbalance does the pediatric team expect to find with sustained tachypnea?

A. Respiratory acidosis results from hypoventilation, where CO₂ is retained, leading to increased carbonic acid and decreased blood pH. This is the opposite of what is expected with tachypnea. B. Metabolic alkalosis is typically caused by loss of gastric acid (e.g., vomiting) or excessive bicarbonate intake, not by altered respiratory rates. C. Metabolic acidosis occurs in conditions such as diarrhea, renal failure, or diabetic ketoacidosis—not directly from changes in respiratory rate. D. Sustained tachypnea (rapid breathing), especially in a child, leads to excessive exhalation of CO₂, reducing carbonic acid levels and raising blood pH, resulting in respiratory alkalosis.