Can sepsis lower the seizure threshold?

From the Research

Sepsis and Seizure Threshold

• Sepsis can lead to sepsis-associated encephalopathy, which is characterized by abnormalities in electroencephalogram (EEG) and somatosensory-evoked potentials, increased biomarkers of brain injury, and neuroradiological abnormalities 1.
• The mechanism of sepsis-associated encephalopathy is complex, involving both inflammatory and noninflammatory processes that affect all brain cells and induce blood-brain barrier breakdown, dysfunction of intracellular metabolism, brain cell death, and brain injuries 1.
• Studies have shown that sepsis can modulate cortical excitability and alter the local and systemic hemodynamic response to seizures, suggesting that sepsis may lower the seizure threshold 2.
• The cytokine storm and overwhelming systemic inflammation in sepsis can trigger the electric circuits that promote seizures, and patients with sepsis-associated encephalopathy can develop convulsive or nonconvulsive seizures 3.

Seizure Risk in Sepsis

• The risk of seizures in sepsis patients is increased, with studies reporting a prevalence of seizures ranging from 1% to 12% 2, 4.
• The use of EEG is indicated in sepsis patients with suspected seizures, and continuous EEG (cEEG) may be useful in detecting nonconvulsive seizures, although its timing, duration, and efficacy are still unknown 3.
• The management of seizures in sepsis patients typically involves the use of benzodiazepines, anticonvulsants, and anesthetic drugs such as propofol or thiopental, which can induce burst suppression and interrupt the pathological electrical circuits 3.

Neurological Complications in Sepsis

• Neurological complications, including septic encephalopathy, ischemic stroke, intracranial hemorrhage, seizures, and posterior reversible encephalopathy syndrome, are common in sepsis patients, with a reported prevalence of 36% for septic encephalopathy and 1% for seizures 4.
• The use of neuromonitoring tools, such as EEG, transcranial Doppler, and near infrared spectroscopy, may be useful in detecting early ischemia and monitoring cerebral hemodynamic changes in sepsis patients 4, 5.
• Cognitive impairment is a common long-term outcome in sepsis survivors, with a reported prevalence of 30% up to 12 months postdischarge 4.