A 68-year-old man presents to the emergency department with confusion and lethargy for the past day. He has a history of end-stage renal disease and has missed his last two dialysis sessions. He also has a history of hypertension, secondary hyperparathyroidism, and hyperphosphatemia. His medications include lisinopril, empagliflozin, cinacalcet, and calcitriol. Vital signs are within normal limits. On physical examination, he is disoriented and has peripheral edema. Laboratory tests reveal a mild normocytic anemia, potassium level of 7.2 mEq/L, blood pH of 7.1, and significantly elevated blood urea nitrogen (BUN) and creatinine levels.
Which of the following is the most appropriate next step in the management of this patient?
B) Initiate emergency dialysis
Indications for acute renal dialysis can be remembered with the AEIOU mnemonic:
- Acidosis: Severe metabolic acidosis, usually with a pH <7.2
- Electrolytes: Hyperkalemia, typically >6.5 mEq/L
- Ingestion: Ingestion of a dialyzable drug or toxin
- Overload: Fluid overload
- Uremia: Symptoms of uremia, such as encephalopathy
This patient presents with severe hyperkalemia (potassium level of 7.2 mEq/L), severe metabolic acidosis (pH of 7.1), and symptoms of uremia (confusion and lethargy), all of which are indications for emergency dialysis.
Answer choice A: Administer intravenous calcium gluconate, is incorrect. While calcium gluconate can stabilize the cardiac membrane when hyperkalemia is present, it does not address the underlying causes requiring dialysis.
Answer choice C: Monitor and recheck labs in 24 hours, is incorrect. This approach is inappropriate given the severity of the patient's condition, which requires immediate intervention.
Answer choice D: Prescribe oral sodium polystyrene sulfonate, is incorrect. This can help lower potassium levels but is not appropriate for immediate management of severe hyperkalemia and will not address the metabolic acidosis and uremia.
Answer choice E: Start bicarbonate therapy, is incorrect. Bicarbonate therapy may help with acidosis but is not sufficient to address the severe hyperkalemia and uremia.
Key Learning Point
Indications for acute renal dialysis can be remembered with the AEIOU mnemonic: acidosis (severe metabolic acidosis, usually with a pH <7.2), electrolytes (hyperkalemia, typically >6.5 mEq/L), ingestion of a dialyzable drug or toxin, overload (fluid overload), and uremia (including encephalopathy).
