Diagnose It Answer — April 14, 2026

66-year-old male on dialysis presents with generalized weakness that started this morning, progressing to difficulty standing from a chair and climbing stairs. He reports feeling 'heavy' in his legs and has had palpitations for the past two hours. He missed his scheduled hemodialysis session two days ago because of transportation issues.

End-stage renal disease on hemodialysis three times per week. History of type 2 diabetes and hypertension. Medications include lisinopril, carvedilol, insulin glargine, and sevelamer. He admits to eating a large amount of bananas, oranges, and tomato-based foods over the past two days. His last dialysis session was four days ago.

BP 162/96 mmHg, HR 58 bpm (bradycardic — normally in the 70s per patient), RR 18 breaths/min, Temp 36.7°C, SpO2 97% on room air. Patient is alert but appears fatigued and has difficulty squeezing the nurse's hand with full strength bilaterally. Muscle strength 3/5 proximal lower extremities.

Cardiac monitor placed immediately on recognition of bradycardia and dialysis history. EKG shows peaked, narrow, symmetric T-waves in precordial leads V2–V5 — classic early hyperkalemia finding. PR interval prolonged at 220ms. No sine wave pattern or wide complex rhythm at this time. Nephrology notified. Calcium gluconate 1g IV ordered as membrane stabilizer. Sodium bicarbonate 50mEq IV, insulin 10 units regular IV with D50W, and albuterol 10mg nebulized ordered to shift potassium intracellularly.

Serum potassium: 7.1 mEq/L (critically elevated; normal 3.5–5.0 mEq/L). Creatinine 9.8 mg/dL (ESRD baseline). BUN 112 mg/dL. CO2 16 mEq/L (metabolic acidosis — exacerbates hyperkalemia by shifting K+ extracellularly). EKG as described: peaked T-waves, prolonged PR, QRS 118ms (upper limit of normal). Nephrology arranging emergent hemodialysis. Kayexalate not given due to dialysis being imminent.