Pearls & Oy-sters: Status epilepticus from hyperammonemia after lung transplant

Even when the cause of metabolic coma seems clear, consider an arterial ammonia level.• Refractory status epilepticus may be due to acute hyperammonemia, and not the more commonly seen calcineurin inhibitor neurotoxicity.• Hyperammonemia causes brain edema and requires multiple measures to lower it quickly.CASE REPORT A 64-year-old woman with familial pulmonary fibrosis underwent bilateral lung transplantation under general anesthesia with midazolam, propofol, and fentanyl.Her post-transplant immunosuppression regimen consisted of prednisone, azathioprine, and tacrolimus.She was initially alert and following commands but on postoperative day 3 became increasingly somnolent, necessitating reintubation.Sodium, renal and liver function tests, and CSF analysis (including opening pressure) were normal.Noncontrast CT scan of the head was unrevealing with no early evidence of cerebral edema.EEG showed diffuse delta with frequent 1-to 2-Hz triphasic waves.Her somnolence was attributed to her tacrolimus level (66.8 ng/mL) and the medication was