Abstracts

Rationale: Burst-suppression (BS) is an electroencephalography (EEG) pattern consisting of alternative periods of burst, with presence or absence of multiple epileptiform discharges, and periods of suppressed background activity (activity < 10 µV) 1. It is generally associated with comatose states of various etiologies (hypoxia, hypothermia, and childhood encephalopathies, and also anesthesia or drugs overdoses)2,3. Despite the improvements in recent years of the critical care to the neurologic impaired patient, is a fact that the deeper degrees of severe brain dysfunction remain a major challenge in what concern prognosis and illness management. The objective of this study is to evaluate the profile of the patients with burst-suppression on EEG and to associate this pattern with the administration of continuous IV sedative medications.Methods: A retrospective review was conducted on patients’ data with burst-suppression pattern on EEG at the Hospital das Clinicas, Faculty of Medicine, University of São Paulo over a one-year period (2014). The profile of the patients was traced and the possible causes for the EEG pattern were evaluated.Results: The burst-suppression pattern was identified in 62 EEG recordings during the year of 2014. These recordings were obtained from 43 patients. After reviewing the charts, 2 patients were excluded due to lack of accurate data registered. 25 (61%) patients were male and 16 (39%) were female, and the ages ranged from 4 years and 4 months to 89 years and 5 months (mean of 48 years and 8 months and standard deviation of 23 years and 7 months). Only 7% of the patients (N=3) were not receiving sedatives. The other 93% (N=39) were under continuous IV sedation, whether with propofol, fentanyl, midazolam, ketamine, thiopental or a combination of two of them.Conclusions: As expected, most of the patients had the burst-suppression pattern secondary to sedatives drugs. The epidemiological findings are also as expect in what concerns age and gender. This pattern is not specific for the different etiologies but is an interesting finding for decisions involving clinical management and further prognosis. 1- Hirsch LJ et al. American Clinical Neurophysiology Society's Standardized Critical Care EEG Terminology: 2012 version. J Clin Neurophysiol. 2013 Feb;30(1):1-2. 2- Kaplan PW, Bauer G. Electroencephalography: Basic principles, clinical applications, and related fields. In: Niedermeyer E, Lopes da Silva F, editors. Anoxia, coma and brain death. Baltimore: Williams and Wilkins; 2011. pp. 435–56 3- Niedermeyer E, Sherman DL, Geocadin RJ, et al. The burst-suppression electroencephalogram. Clin Electroencephalogr. 1999;30(3):99–105.