NCLEX-PN® ExaminationPhysiological AdaptationMedium
A client is admitted with diabetic ketoacidosis (DKA). The nurse anticipates which of the following arterial blood gas (ABG) results?
- ApH 7.30, PaCO2 30 mmHg, HCO3 18 mEq/L
- BpH 7.50, PaCO2 30 mmHg, HCO3 28 mEq/L
- CpH 7.48, PaCO2 40 mmHg, HCO3 30 mEq/L
- DpH 7.20, PaCO2 50 mmHg, HCO3 24 mEq/L
Show answer & explanationAnswer & explanation
Correct answer: A. pH 7.30, PaCO2 30 mmHg, HCO3 18 mEq/L
Diabetic ketoacidosis (DKA) is a state of metabolic acidosis. This means the pH will be low (<7.35) and the bicarbonate (HCO3) will be low (<22 mEq/L) due to the accumulation of ketoacids. The body tries to compensate by hyperventilating (Kussmaul respirations) to blow off CO2, which results in a low PaCO2 (<35 mmHg). Option A reflects these values: pH 7.30 (acidic), PaCO2 30 mmHg (low, compensatory), HCO3 18 mEq/L (low, metabolic acidosis).
Why the other options are wrong
- B. This indicates respiratory alkalosis with metabolic compensation, which is incorrect for DKA.
- C. This indicates metabolic alkalosis, which is incorrect for DKA.
- D. This indicates respiratory acidosis, which is incorrect for DKA.
Diabetic Ketoacidosis (DKA) ABGs
A severe complication of diabetes characterized by hyperglycemia, ketosis, and metabolic acidosis, primarily due to profound insulin deficiency.
- Primary acid-base imbalance is metabolic acidosis.
- Low pH (<7.35) and low bicarbonate (HCO3 <22 mEq/L).
- Compensatory mechanism is Kussmaul respirations (hyperventilation), leading to low PaCO2 (<35 mmHg).
Memory trick: DKA = Down pH, Down Bicarb, Down CO2 (compensating)