Correct!
1. Elevated anion gap metabolic acidosis
His tCO2, or bicarbonate, is low indicating a metabolic acidosis. Metabolic acidosis is separated into two categories-normal anion gap metabolic acidosis and elevated anion gap metabolic acidosis. The anion gap (AG) is calculated by subtracting the concentration of two anions, chloride ([Cl-]) and bicarbonate ([HCO3-]) from the concentration of the major cations, sodium ([Na+ and potassium ([K+]) (2):
AG = ([Na+] + [K+]) - ([Cl-] + [HCO3-])
The anion gap is normally < 12 mEq/L. Our patient’s anion gap is elevated AG = (129 + 5)– (100 + 5) = 29. A normal anion gap metabolic acidosis usually indicates a loss of HCO3- most commonly through the gastrointestinal tract. An elevated anion gap indicates a metabolic acidosis caused by an acid, which has been titrated by the body’s
bicarbonate-carbonic acid buffer system and released its unmeasured anion.
Which of the following would be useful in determining the cause of the patient’s elevated anion gap metabolic acidosis? (Click on the correct answer to be directed to the fourh of six pages)