A 50-year-old man with end-stage kidney disease receiving hemodialysis was admitted to the hospital for treatment of calciphylaxis and foot cellulitis. His home medications included sevelamer and hydrocodone-acetaminophen (10 mg/325 mg) every 8 hours as needed, which was increased to every 4 hours as needed in the hospital. Hydromorphone (0.5 mg intravenously as needed) was added for breakthrough pain. He was prescribed chewable lanthanum tablets (500 mg 3 times daily) for treatment of a blood phosphate level of 8.1 mg/dL (reference, 2.5-4.5 mg/dL).
On hospital day 7, the patient developed intermittent apneic episodes, during which his oxygen saturation was 80% on room air; heart rate, 86/min; and blood pressure, 106/45 mm Hg. Physical examination revealed bilateral rhonchi and responsiveness to verbal commands only with deep painful stimulus. A chest radiograph showed 4 radio-opaque coin-shaped opacities in the stomach (Figure). After administration of oxygen at 2 L/min by nasal cannula and a naloxone infusion, his oxygen saturation increased to 98% and his mental status improved. The patient reported no foreign body ingestion.