The following arterial blood gas (ABG) results indicate? pH-7.68 PaCO2-30 mmHg Pa02-81 mmHg HCO3-16.2 mEq/L BE-(+21.2) 02 Sat-91%

A. Respiratory alkalosis: The pH of 7.68 indicates alkalemia, and the PaCO2 is decreased at 30 mmHg, demonstrating a primary respiratory disturbance. The low PaCO2 is consistent with hyperventilation, which causes excessive CO2 exhalation, leading to alkalosis. Although HCO3- is slightly decreased, this likely represents a compensatory metabolic response rather than a primary metabolic disorder, aligning with respiratory alkalosis as the principal abnormality. B. Respiratory acidosis: Respiratory acidosis is characterized by acidemia (pH 45 mmHg) due to hypoventilation or impaired gas exchange. In this ABG, the pH is alkalotic and PaCO2 is decreased, which is opposite the pattern seen in respiratory acidosis. C. Normal ABG results: Normal ABG parameters include pH 7.35–7.45, PaCO2 35–45 mmHg, HCO3- 22–28 mEq/L, and PaO2 80–100 mmHg. This patient’s pH is significantly elevated, PaCO2 is below normal, HCO3- is reduced, and base excess is abnormal, all indicating a pathophysiologic process rather than a normal state. D. Metabolic acidosis: Metabolic acidosis involves low pH and decreased HCO3- as the primary disturbance. Although HCO3- is reduced at 16.2 mEq/L, the elevated pH and decreased PaCO2 indicate alkalemia with a primary respiratory origin, making metabolic acidosis an incorrect interpretation.