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Obesity has been associated with COVID-19 and with pneumonia and acute respiratory distress syndrome but is also associated with comorbidities that place patients at higher risk. This study examines whether obesity is associated with intubation or death—as well as biomarkers of inflammation, cardiac injury, or fibrinolysis—in the context of COVID-19 disease independent of obesity-related comorbidities.

IMPORTANCE Periodic discharges (PDs) that do not meet seizure criteria, also termed the ictal interictal continuum, are pervasive on electroencephalographic (EEG) recordings after acute brain injury. However, their association with brain homeostasis and the need for clinical intervention remain unknown.OBJECTIVE To determine whether distinct PD patterns can be identified that, similar to electrographic seizures, cause brain tissue hypoxia, a measure of ongoing brain injury. DESIGN, SETTING, AND PARTICIPANTSThis prospective cohort study included 90 comatose patients with high-grade spontaneous subarachnoid hemorrhage who underwent continuous surface (scalp) EEG (sEEG) recording and multimodality monitoring, including invasive measurements of intracortical (depth) EEG (dEEG), partial pressure of oxygen in interstitial brain tissue (PbtO 2 ), and regional cerebral blood flow (CBF). Patient data were collected from June 1, 2006, to September 1, 2014, at a single tertiary care center. The retrospective analysis was performed from September 1, 2014, to May 1, 2016, with a hypothesis that the effect on brain tissue oxygenation was primarily dependent on the discharge frequency.MAIN OUTCOMES AND MEASURES Electroencephalographic recordings were visually classified based on PD frequency and spatial distribution of discharges. Correlations between mean multimodality monitoring data and change-point analyses were performed to characterize electrophysiological changes by applying bootstrapping. RESULTSOf the 90 patients included in the study (26 men and 64 women; mean [SD] age, 55 [15] years), 32 (36%) had PDs on sEEG and dEEG recordings and 21 (23%) on dEEG recordings only. Frequencies of PDs ranged from 0.5 to 2.5 Hz. Median PbtO 2 was 23 mm Hg without PDs compared with 16 mm Hg at 2.0 Hz and 14 mm Hg at 2.5 Hz (differences were significant for 0 vs 2.5 Hz based on bootstrapping). Change-point analysis confirmed a temporal association of high-frequency PD onset (Ն2.0 Hz) and PbtO 2 reduction (median normalized PbtO 2 decreased by 25% 5-10 minutes after onset). Increased regional CBF of 21.0 mL/100 g/min for 0 Hz, 25.9 mL/100 g/min for 1.0 Hz, 27.5 mL/100 g/min for 1.5 Hz, and 34.7 mL/100 g/min for 2.0 Hz and increased global cerebral perfusion pressure of 91 mm Hg for 0 Hz, 100.5 mm Hg for 0.5 Hz, 95.5 mm Hg for 1.0 Hz, 97.0 mm Hg for 2.0 Hz, 98.0 mm Hg for 2.5 Hz, 95.0 mm Hg for 2.5 Hz, and 67.8 mm Hg for 3.0 Hz were seen for higher PD frequencies.CONCLUSIONS AND RELEVANCE These data give some support to consider redefining the continuum between seizures and PDs, suggesting that additional damage after acute brain injury may be reflected by frequency changes in electrocerebral recordings. Similar to seizures, cerebral blood flow increases in patients with PDs to compensate for the increased metabolic demand but higher-frequency PDs (>2 per second) may be inadequately compensated without an additional rise in CBF and associated with brain tissue hypoxia, or higher-frequency PDs may reflect inadequacies in brain compensatory...

Objective:To test ketamine infusion efficacy in the treatment of super-refractory status epilepticus (SRSE), we studied retrospectively SRSE patients who were treated with ketamine. Additionally, we studied the effect of high doses of ketamine on brain physiology as reflected by invasive multimodality monitoring (MMM).Methods:We studied a consecutive series of 68 SRSE patients who were admitted between 2009 and 2018, were treated with ketamine and monitored with scalp EEG. Eleven of these patients underwent MMM at the time of ketamine administration. We compared patients who had seizure cessation after ketamine initiation to those who did not.Results:Mean age was 53+/-18 years old, 46% of patients were female. Seizure burden decreased by at least 50% within 24 hours of starting ketamine in 55 (81%) patients, with complete cessation in 43 (63%). Average dose of ketamine infusion was 2.2+/-1.8 mg/kg/h, with median duration of 2 (1; 4) days. Average dose of midazolam was 1.0+/-0.8 mg/kg/h at the time of ketamine initiation and was started at a median of 0.4 (0.1; 1.0) days before ketamine. Using a generalized linear mixed effect model, ketamine was associated with stable mean arterial pressure (OR 1.39, 95% CI 1.38-1.40), and with decreased in vasopressor requirements over time. We found no effect on intracranial pressure, cerebral blood flow, and cerebral perfusion pressure.Conclusion:Ketamine treatment was associated with a decrease in seizure burden in patients with SRSE. Our data support the notion that high dose ketamine infusions are associated with decreased vasopressor requirements without increased intracranial pressure.Classification of Evidence:This study provides Class IV evidence that ketamine decreases seizures in patients with SRSE.