ITE Diabetic Ketoacidosis and HHS 4 — Questions and Answers
Question 1: A patient with DKA has an initial serum bicarbonate of 8 mEq/L and pH of 7.10. Under which circumstance is sodium bicarbonate administration recommended by most guidelines?
- pH < 7.30 with any symptom
- pH < 7.10 or life-threatening hyperkalemia (Correct answer)
- Bicarbonate < 10 mEq/L regardless of pH
- Routine use in all moderate-to-severe DKA
Correct answer: pH < 7.10 or life-threatening hyperkalemia
Bicarbonate therapy is generally reserved for severe acidosis (pH < 7.0-7.10) or life-threatening hyperkalemia; routine use may worsen outcomes.
Question 2: A 70-year-old nursing home resident with type 2 DM is found unresponsive. Labs show glucose 1,350 mg/dL, Na 152, osmolality 385 mOsm/kg, pH 7.35, bicarbonate 22. What is the diagnosis?
- Severe DKA with hyperosmolality
- Hyperosmolar hyperglycemic state (HHS) (Correct answer)
- Mixed DKA and HHS
- Lactic acidosis
Correct answer: Hyperosmolar hyperglycemic state (HHS)
HHS is characterized by extreme hyperglycemia (>600 mg/dL), hyperosmolality (>320 mOsm/kg), and absent or minimal ketoacidosis (pH >7.3, bicarb >18).
Question 3: Which of the following correctly describes the mortality difference between DKA and HHS?
- DKA has higher mortality than HHS
- HHS has higher mortality than DKA (Correct answer)
- Mortality is equal between DKA and HHS
- DKA is fatal in >50% of cases in modern ICUs
Correct answer: HHS has higher mortality than DKA
HHS carries higher mortality (~15%) compared to DKA (~1-5%), largely because it affects older patients with more comorbidities and often presents later.
Question 4: A patient with DKA has a measured osmolal gap of 22 mOsm/kg (normal <10). Which additional intoxication must be considered?
- Salicylate toxicity
- Ethylene glycol or methanol poisoning (Correct answer)
- Acetaminophen toxicity
- Isoniazid toxicity
Correct answer: Ethylene glycol or methanol poisoning
An elevated osmolal gap in the context of metabolic acidosis should prompt evaluation for toxic alcohol ingestion (ethylene glycol, methanol, isopropanol).
Question 5: During DKA treatment, a patient's repeat labs show glucose 190, pH 7.28, anion gap 16 (still elevated), and bicarbonate 16. What is the most appropriate action?
- Stop insulin and start subcutaneous regimen
- Add dextrose to fluids and continue insulin infusion (Correct answer)
- Administer sodium bicarbonate to close the gap
- Increase IV fluid rate to 500 mL/hr
Correct answer: Add dextrose to fluids and continue insulin infusion
Because the anion gap is still elevated, the ketoacidosis has not resolved; dextrose should be added to IV fluids to prevent hypoglycemia while continuing insulin.
Question 6: Which of the following is the preferred initial fluid for a patient presenting with DKA and hemodynamic instability (BP 80/50)?
- 0.45% NaCl at 250 mL/hr
- 0.9% NaCl at 1 L/hr bolus (Correct answer)
- Lactated Ringer's solution at 500 mL/hr
- Colloid (albumin) infusion
Correct answer: 0.9% NaCl at 1 L/hr bolus
Isotonic 0.9% NaCl is the initial fluid of choice for volume resuscitation in DKA, particularly in hemodynamically unstable patients.
Question 7: A patient with type 1 DM develops DKA during pregnancy at 28 weeks gestation. Which unique consideration applies to DKA management in pregnancy?
- Target glucose of 200-250 mg/dL to avoid hypoglycemia in fetus
- DKA may occur at lower glucose levels (as low as 200 mg/dL) in pregnancy (Correct answer)
- Insulin should be avoided in first trimester DKA
- Fetal distress resolves only after delivery, not with maternal treatment
Correct answer: DKA may occur at lower glucose levels (as low as 200 mg/dL) in pregnancy
Pregnant patients are at risk for 'euglycemic DKA' with lower glucose thresholds due to altered metabolism, increased insulin resistance, and decreased buffering capacity.
ITE Diabetic Ketoacidosis and HHS 4
A patient with DKA has an initial serum bicarbonate of 8 mEq/L and pH of 7.10.
Under which circumstance is sodium bicarbonate administration recommended by most guidelines?