Postrenal acute kidney injury Quiz: Ace Your Exams

A 52-year-old man presents to the emergency department for evaluation of shortness of breath for one week. He reports orthopnea and dyspnea on exertion and has also had ongoing difficulty fully emptying his bladder. The patient's medical history is significant for obesity and hypertension, but the patient has not taken any blood pressure medications in several months. He does not smoke or drink alcohol. Temperature is 37°C (98.6°F), blood pressure is 205/77 mmHg, heart rate is 130 beats per minute, respiratory rate is 16 breaths per minute, and oxygen saturation is 94% on room air. On physical examination, the patient appears uncomfortable. Cardiopulmonary examination reveals faint bilateral rales and 2+ pitting edema in both lower extremities. Suprapubic fullness is noted, and bladder scanning shows approximately 1L of urine. Laboratory studies are detailed below. An electrocardiogram (ECG) reveals peaked T-waves and QRS widening. The patient receives intravenous furosemide, calcium gluconate, insulin with dextrose, and albuterol. A Foley catheter is placed without complication. What is the most appropriate next step in management?

Serum chemistry
Laboratory value	Result
Sodium	142 mEq/L
Potassium	7.1 mEq/L
Chloride	95 mEq/L
BUN	130 mg/dL
Creatinine	11.2 mg/dL (baseline 0.8 mg/dL 2 months ago)
Albumin	3.2 g/dL
Venous pH	7.28