The researchers investigate the use of a simplified electroencephalogram (point-of-care EEG) in the pediatric emergency department for children with impaired consciousness or an ongoing epileptic seizure ("status epilepticus"). In addition, the researchers will compare the simplified EEG with the conventional EEG in the epilepsy outpatient clinic.

Non-traumatic, acute central nervous system (CNS) disorders are amongst the most frequent emergencies in childhood. In Switzerland, CNS disorders are the top ranking presentation of critically ill children. Many pediatric neurological emergencies such as coma, acute encephalopathies with impaired consciousness or agitation, or acute focal deficits, are associated with changes of cortical electrical activity detectable by the electroencephalogram (EEG). Of particular concern are status epilepticus (SE) and non-convulsive status epilepticus (NCSE). Previous studies have shown that an EEG can yield important diagnostic information and aid in decision-making. However, conventional EEG-recordings are resource intensive (time, staff), and hardly available outside of regular working hours. Point-of-care EEG (pocEEG) has proven helpful for evaluating impaired consciousness, detecting NCSE, and monitoring therapy in ongoing SE. In a retrospective cohort study from Japan patients with impaired consciousness were diagnosed with non-convulsive seizures in pocEEG, supporting the view that pocEEG can be applied by ED physicians, even in the absence of a neurologist, and can aid the detection and treatment of non-convulsive seizures. Another study, also from Japan, reported that abnormalities were detected in 20% of patients by using pocEEG in an ED setting. The aims of this study are:

• To prospectively assess the feasibility and utility of pocEEG for NCSE detection in children presenting with impaired consciousness in the PED
• To evaluate the interpretation accuracy of pocEEG by pediatric emergency medicine (PEM) providers after a teaching module.
• To compare pocEEG to the "gold standard" of simultaneously recorded conventional EEG in patients undergoing routine cEEG in the epilepsy outpatient clinics.

Inclusion Criteria:

General:

PED:

• Pediatric patients with unexplained impaired consciousness, suspicion of NCSE, active SE presenting to the PED
• Informed consent of patient of parents/persons responsible, if possible, otherwise emergency situation procedure (according to national regulations for research in emergency situations)

CLINIC:

• Informed consent as documented by signature
• Pediatric patients undergoing cEEG in the outpatient epilepsy clinics
• Either suspected/ to rule out epilepsy or established diagnosis of epilepsy

Exclusion Criteria:

PED:

• AMS of known etiology or another diagnosis
• Declined informed consent

CLINIC:

• Failure to provide signed informed consent
• Changes in health condition which might interfere with the EEG recording.

All pediatric patients presenting to the PED or the epilepsy clinic fulfilling the inclusion criteria.