Pearls and Pitfalls of Introducing Ketogenic Diet in Adult Status Epilepticus: A Practical Guide for the Intensivist

Abstract

Background: Status epilepticus (SE) carries an exceedingly high mortality and morbidity, often warranting an aggressive therapeutic approach. Recently, the implementation of a ketogenic diet (KD) in adults with refractory and super-refractory SE has been shown to be feasible and effective. Methods: We describe our experience, including the challenges of achieving and maintaining ketosis, in an adult with new onset refractory status epilepticus (NORSE). Case Vignette: A previously healthy 29-year-old woman was admitted with cryptogenic NORSE following a febrile illness; course was complicated by prolonged super-refractory SE. A comprehensive work-up was notable only for mild cerebral spinal fluid (CSF) pleocytosis, elevated nonspecific serum inflammatory markers, and edematous hippocampi with associated diffusion restriction on magnetic resonance imaging (MRI). Repeat CSF testing was normal and serial MRIs demonstrated resolution of edema and diffusion restriction with progressive hippocampal and diffuse atrophy. She required prolonged therapeutic coma with high anesthetic infusion rates, 16 antiseizure drug (ASD) trials, empiric immunosuppression and partial bilateral oophorectomy. Enteral ketogenic formula was started on hospital day 28. However, sustained beta-hydroxybutyrate levels >2 mmol/L were only achieved 37 days later following a comprehensive adjustment of the care plan. KD was challenging to maintain in the intensive care unit (ICU) and was discontinued due to poor nutritional state and pressure ulcers. KD was restarted again in a non-ICU unit facilitating ASD tapering without re-emergence of SE. Discussion: There are inconspicuous carbohydrates in commonly administered medications for SE including antibiotics, electrolyte repletion formulations, different preparations of the same drug (i.e., parenteral, tablet, or suspension) and even solutions used for oral care-all challenging the use of KD in the hospitalized patient. Tailoring comprehensive care and awareness of possible complications of KD are important for the successful implementation and maintenance of ketosis.

Keywords: critical care; ketogenic diet; ketosis; new onset refractory status epilepticus; seizures; status epilepticus.

Figure 1

Drug Interference with achievement of ketosis. Seizure Activity: On HD 14–16, seizure burden was 90% nonconvulsive status epilepticus (NCSE) and decreased to 10–15% by hospital day (HD) 23–24. From HD 30–39, % ictal ranged from 5–20% with HD 40 showing <1% ictal. % Ictal increased briefly during HD 41–47 with an average of 15% ictal but decreased to <1% by HD 48/49. % Ictal remained in the 10–20% range until HD 57 with % ictal < 1. From HD 58–72 % ictal ranged from 5–20% until % ictal <5 by HD 72.