Abstracts

Rationale: Continuous EEG monitoring in the neuro-intensive care unit is becoming more prevalent. A high prevalence of subclinical seizures would justify more extensive use of continuous EEG monitoring. Methods: 122 ( 70 male, 52 female) consecutive patients undergoing long =term EEG monitoring ( LTME) in critical care setting were reviewed. The prevalence of interictal and ictal abnormalities was evaluated as well as diagnosis, length of stay, re-admission rate, as well as disposition. Statistical analysis was performed utilizing Fisher exact test and Wilcox Rank Sum. Results: 21% of patients had ictal activity during the monotoring period. Subclinical seizures were noted in 13% of patients. Only four patients had initial ictal findings. Readmission rates in patients with seizures were 38% as compared to 18% in patients without seizures ( p=0.1).30.4% of patients with sharp waves or Periodic lateralized epileptiform abnormalities had seizures, but seizures still occured in 7.6% of patients without these findings (p=0.003) Conclusions: Subclinical and Clinical Seizures relatively common in the neuro-intensive care unit. These seizures may be unrecognized during initial EEG recordings and may be associated with increased length of stay.