CCRN Endocrine and Metabolic Crises 3 — Questions and Answers
Question 1: A patient with DKA has an arterial blood gas showing pH 7.18, HCO3 8 mEq/L. This represents which acid-base disturbance?
- High anion gap metabolic acidosis (Correct answer)
- Respiratory alkalosis
- Metabolic alkalosis
- Respiratory acidosis
Correct answer: High anion gap metabolic acidosis
Accumulation of ketoacids in DKA produces a high anion gap metabolic acidosis with low pH and low bicarbonate.
Question 2: Kussmaul respirations observed in a DKA patient represent what compensatory mechanism?
- Respiratory compensation to blow off CO2 and reduce acidosis (Correct answer)
- Airway obstruction
- Pulmonary edema
- Hyperventilation from anxiety
Correct answer: Respiratory compensation to blow off CO2 and reduce acidosis
Deep, rapid Kussmaul breathing is the lungs compensating for metabolic acidosis by eliminating CO2.
Question 3: Which patient is at highest risk for hyperosmolar hyperglycemic state (HHS)?
- An elderly patient with type 2 diabetes and an acute infection (Correct answer)
- A young athlete with type 1 diabetes
- A child with new-onset diabetes
- A patient with well-controlled type 1 diabetes
Correct answer: An elderly patient with type 2 diabetes and an acute infection
HHS classically occurs in older type 2 diabetics with a precipitating illness such as infection causing severe dehydration and hyperglycemia.
Question 4: A patient receiving an insulin infusion for HHS requires careful glucose lowering primarily to prevent which complication?
- Cerebral edema from rapid osmotic shifts (Correct answer)
- Hyperkalemia
- Liver failure
- Pulmonary fibrosis
Correct answer: Cerebral edema from rapid osmotic shifts
Lowering glucose and osmolality too quickly causes rapid fluid shifts into the brain, risking cerebral edema.
Question 5: A patient with syndrome of inappropriate antidiuretic hormone (SIADH) would be expected to have which sodium and fluid status?
- Hyponatremia with fluid retention (Correct answer)
- Hypernatremia with dehydration
- Hypernatremia with fluid overload
- Normal sodium with dehydration
Correct answer: Hyponatremia with fluid retention
Excess ADH causes water retention and dilutional hyponatremia with concentrated urine.
Question 6: Which treatment is appropriate for symptomatic SIADH with severe hyponatremia?
- Fluid restriction and possibly hypertonic saline (Correct answer)
- Aggressive hypotonic IV fluids
- Free water boluses
- Desmopressin administration
Correct answer: Fluid restriction and possibly hypertonic saline
SIADH is managed with fluid restriction, and severe symptomatic hyponatremia may require cautious hypertonic saline.
Question 7: A patient with diabetes insipidus (DI) typically presents with which findings?
- Polyuria with dilute urine and hypernatremia (Correct answer)
- Oliguria with concentrated urine
- Hyponatremia with fluid overload
- Anuria with low serum sodium
Correct answer: Polyuria with dilute urine and hypernatremia
DI results from ADH deficiency or resistance, causing massive output of dilute urine, dehydration, and hypernatremia.
CCRN Endocrine and Metabolic Crises 3
A patient with DKA has an arterial blood gas showing pH 7.18, HCO3 8 mEq/L.
This represents which acid-base disturbance?