Status Dystonicus Following Deep Brain Stimulation Surgery in DYT1 Dystonia Patients (P01.227)

Abstract

Objective: We describe a case series of patients who experienced status dystonicus (SD), also known as dystonic storm, following deep brain stimulation (DBS) surgery to implant or remove electrodes in the globus pallidus pars interna (GPi). Background SD is a rare complication of primary and secondary dystonia characterized by acute and severe worsening of dystonic movements, often to the point where it is considered a life-threatening emergency. Of approximately 50 cases described in the literature, 14 used DBS as an acute treatment, whereas one case reported SD arising after lead explantation. To our knowledge, SD following DBS implantation has not yet been described. Design/Methods: Medical records of DBS surgeries for dystonia were reviewed, with criteria being 1) clear documentation of SD event and 2) level of severity requiring critical-care support or the presence of end organ involvement. Demographic data collected included age, ethnicity, duration of disease, DYT1 status and BFMDRS scores. The severity and course of each episode were tracked by the duration of ICU admission, IV sedation requirements, mechanical ventilation, as well as abnormal CK, liver, or renal failure. Results: We found six episodes of SD across 3 patients. Presumed causes included: 1) surgical stress from the DBS lead implantation (n=3); 2) sudden cessation of stimulation (n=2) or baclofen pump function (n=1). The duration of these episodes ranged from 3 to 29 days in the ICU with a similar duration of continuous IV sedation requirements. All patients recovered to their baseline dystonia severity, with early initiation of pallidal stimulation in 4 of 6 episodes. Conclusions: These cases suggest that stereotactic implantation or sudden removal of DBS electrodes may trigger SD. While early DBS activation may improve and expedite SD outcomes, it is important to closely monitor patients post-operatively for unexpected deterioration of symptoms, including SD in extreme cases. Supported by: Dr. Cheung has received travel support from Dystonia Coalition grant #NS067501. Disclosure: Dr. Cheung has received research support from Medtronic, Inc. Dr. Flatow has nothing to disclose. Dr. Ben-Haim has nothing to disclose. Dr. Osborn has nothing to disclose. Dr. Cho has nothing to disclose. Dr. Tagliati has received personal compensation for activities with Medtronic Ipsen, Merz and St.Jude as a speaker, consultant and participant on an advisory board. Dr. Alterman received personal compensation for activities with Medtronic, Inc. Dr. Alterman has received research support from Ceregene, Inc and ANS.