Neonatal EEG/ Terms Flashcards
Information that must be included in the study information available to the electroencephalographer
The baby’s gestational age at birth, chronologic age, and postmenstrual age on the day of recording, stated in weeks
Postmenstrual age (PMA) is
gestational age (GA) plus chronological age (CA)
Gestational age (GA) is
the time elapsed between the first day of the last menstrual period and the day of delivery
Chronological age (CA) is
the time elapsed since birth
aka Legal Age
Aside from the baby’s age, document…
- the patient’s temperature - especially in cases of hypothermia
- if there is a modified/ double-distance lead placement
*Head Circumference
What to expect of Neonatal EEG
weeks 24-31
- Monomorphic Occipital Delta
- Rhythmic Temporal Theta
- IBI (Interburst Interval) up to 30 sec, as baby matures IBI shortens and bursts lengthen
- Trace Discontinue in Quiet Sleep
- No reactivity until 30 wks
- Amplitude <2uV
- Synchronous but asymmetry between the hemispheres
*Delta Brush
What to expect of Neonatal EEG
weeks 32-35
- Delta brushes peak
- Trace Discontinue becoming Trace Alternant
- Anterior Dysrhythmia starts
- Encoches Frontales starts
- Activite moyenne starts
- Awake & Active sleep increases in continuity
What to expect of Neonatal EEG
weeks 37-40
- Continuous wake & active sleep
- Increasing in synchrony
- Trace Discontinue becomes Trace Alternant
*Decreasing occurrence of Delta brushes - Attenuation with reactivity
What to expect of Neonatal EEG
weeks 40-44
- Trace Alternant replaced by Cont. Slow Wave Sleep in Quiet Sleep
continuous, reactive, synchronous
What to expect of Neonatal EEG
weeks 44-46
develops V-Waves and spindles, delta brushes & trace alternant are gone
PDR by 48 weeks
Parameters most frequently monitored along with EEG in infants are:
heart rate (ECG), respirations, and eye movements.
In neonates with invariant patterns, it may be necessary to obtain at least:
60 minutes of recording to demonstrate that the tracings are not likely to change.
An adequate neonatal sleep tracing must include:
a full epoch of quiet sleep.
The yield of EEG monitoring to confirm the epileptic basis of isolated, paroxysmal autonomic signs (e.g., isolated paroxysmal increases in the heart rate or blood pressure) is:
low
when episodes of autonomic dysfunction are the result of seizures, they can only be accurately identified by:
EEG monitoring
most neonatal seizures are:
subclinical (i.e., they have no outwardly visible clinical signs and may only be identified by EEG monitoring).
Clinical settings in which to suspect neonatal seizures:
- Infants who are at a high risk for acute brain injury
- those with demonstrated acute brain injury
- those with clinically suspected seizures or neonatal epilepsy syndromes
Examples of Sudden, Stereotyped Clinical Events
That May Raise the Suspicion for Neonatal Seizures
- Focal clonic or tonic movements
- Intermittent forced, conjugate, horizontal gaze deviation
- Myoclonus
- Generalized tonic posturing
- “Brainstem release phenomena” such as oral–motor stereotypes, reciprocal swimming movements of the upper extremities or bicycling movements of the legs
- Autonomic paroxysms such as unexplained apnea, pallor, flushing, tearing, and cyclic periods of tachycardia or elevated blood pressures
the recommended electrode locations for single-channel aEEG recordings obtained in isolation are
P3 and P4
because they overlie the apices of the cerebrovascular
watershed zones
artifacts that may mimic neonatal electrographic seizures
- chest physical therapy
- patting
- sucking on a pacifier or endotracheal tube
- high frequency or conventional ventilation artifacts
- extra corporeal membrane oxygenator pump artifacts
- electrocardiogram
- pulsatile fontanelle
- or other environmental or electrical interference
For high-risk infants, a _____ long EEG is considered inadequate to screen for seizures.
1-hour
Ideally, the EEG technologist should remain at bedside for the _______ of recording to ____________________________.
- first hour
- ensure a high quality recording and to make note of relevant clinical signs.
activité moyenne
roughly meaning “average or medium”
EEG background has continuous, low to medium voltage [25-50 mV peak-to-peak (pp)] mixed frequency activity with a predominance of theta and delta and overriding beta activity
Active Sleep
healthy term neonate in active sleep has eyes closed, intermittent periods of rapid eye movements, and irregular respirations with small and large body movements. The EEG background shows activité moyenne, indistinguishable from that of normal wakefulness.
Tracé discontinu
EEG pattern characterized by bursts of medium voltage theta/ delta activity with interburst intervals (IBI) of inactivity.
As neonate matures from 35w PMA -> 44-45w PMA pattern becomes CSWS
Quiet Sleep
Quiet sleep is clinically characterized by eye closure, absence of rapid eye movements, and scant body movements, except for occasional sucking activity or generalized myoclonic “startles.”
*Near term (~37w PMA), the quiet sleep EEG background tracé alternant, evolves from the less mature tracé discontinu in the preterm *
PDR by age:
4-5Hz by 6 months
6Hz by 1 year
7Hz by 2 years
8Hz by 3 years
9Hz by 8 years
10Hz by 10 years
Neonate terms SGA and LGA mean what?
SGA= Small for Gestational Age - Infants who weighs < the 10th percentile
LGA= Large for Gestational Age - Infants who weighs > 90th percentile
Per the American Academy of Pediatrics define term, preterm and post term:
Preterm= less than 37 weeks PMA
Term= 37-44 weeks PMA
Post Term= 44-48 weeks PMA
Delta Brush
aka as: ripples of prematurity, rapid bursts
Defined by: high amplitude delta with superimposed fast activity
Appears at 27w PMA, max 32-34w PMA, should disappear by 44w PMA
Temporal Theta Bursts
aka: Temporal sharp transients, temporal sawtooth waves
Defined by: brief bursts of rhythmic sharply contoured temporal theta.
Occurs at: 29-32w PMA
Monomorphic Occipital Delta
Defined by: medium to high amplitude delta activity in the occipital regions.
Occurring 29-32w PMA
Activite’ moyenne
average amplitude and frequency delta/ theta with superimposed beta.
Develops at 34/35w PMA seen in active sleep in 34-37w PMA
Enoches Frontales
high amplitude frontal sharp transients occurring bilaterally or unilaterally asynchronously during transition from active to quiet sleep.
Appear at 35/36w PMA, sharper at 36/37w PMA, persist until 44w PMA
Trace Alternant
Similar to trace discontinu but occurs in older/ more developed neonates.
Defined as: bursts of theta and delta activity lasting 2-5 seconds in quiet sleep. During IBI there is lower amp mixed frequency activity of beta /alpha lasting 1-30 seconds
Develops around 34-37w PMA
