Utility of Prolonged Bedside Amplitude-Integrated Encephalogram in Encephalopathic Infants

Abstract

We hypothesized that prolonged bedside limited-channel amplitude-integrated electroencephalogram (aEEG) monitoring following a standard 1-hour conventional electroencephalogram (cEEG) would increase the detection of subclinical seizures and allow continuous evaluation of the background EEG in neonatal encephalopathy. This may identify complementary roles for these EEG technologies in neonatal units where continuous cEEG monitoring may not be readily available. We prospectively recruited 25 term neonates with a diagnosis of neonatal seizures or encephalopathy. All infants underwent a standard 1-hour cEEG followed by 12 to 24 hours of aEEG monitoring. Data from the aEEG (plus the raw signal) were analyzed by an epileptologist and compared with information obtained from the clinical report of the cEEG. aEEG and cEEG data were available for 24 infants. Results from magnetic resonance imaging (MRI) performed at 7 to 10 days of life were available in 23/24 infants. Background classification on cEEG and aEEG was similar in 83% of patients. Five of 24 infants had normal background on cEEG. Prolonged aEEG detected evolution of background from initially normal to moderately abnormal in an additional four infants. It also detected more subclinical seizures than the 1-hour cEEG in 8/14 infants. Normal background on aEEG and cEEG was associated with normal MRI results, and severe background abnormality (5/24) on both aEEG and cEEG was associated with abnormal MRI results. Data obtained from prolonged aEEG (plus raw EEG) provide similar background activity, enhance seizure detection, and complement standard cEEG in predicting short-term outcomes, based on MRI, in term neonates with seizures or encephalopathy. Limited-channel aEEG technology may provide a pragmatic alternative for longitudinal monitoring of newborn infants with encephalopathy in neonatal units where prolonged video EEG monitoring is not feasible.

Seizure Detection by Critical Care Providers Using Amplitude-Integrated Electroencephalography and Color Density Spectral Array in Pediatric Cardiac Arrest Patients

“…Our results suggest that aEEG might be overall easier to interpret which could explain why combining aEEG with CDSA appeared to improve seizure detection rates over CDSA alone. aEEG displays seizures as changes in peak-to-peak amplitude (19, 24) whereas CDSA displays seizures as high power through a Fourier transformation of both amplitude and frequency(15). CDSA provides a different dimension to seizures with color displays of power.…”

“…CDSA uses Fourier transformation to present EEG power (amplitude 2 /Hz) (color) and frequency (y-axis) over time (x-axis). They both have the advantage of displaying several hours of compressed EEG data as a single image (15, 19, 24)(Figure 1). …”

Using amplitude-integrated EEG in neonatal intensive care

“…Several studies examined the utility of aEEG in comparison with conventional and/or video-EEG in this infant population, finding that aEEG was not only reliable but also complemented cEEG in more than one aspect. 14,26 A recent pilot study on the feasibility of aEEG in our tertiary-care NICU showed that 73% of seizures >30 s and 87% >60 s were detected by the aEEG seizure algorithm. 27 Furthermore, when compared with a blinded study group, patients whose tracings were visible to bedside physicians showed a trend toward reduced seizure burden without evidence of overtreatment.…”

Comparison Between Simultaneously Recorded Amplitude Integrated Electroencephalography and Standard Electroencephalography in Neonates with Acute Brain Injury

“…Rutin yenidoğan cEEG'sinin akut, ağır beyin hasarı sonrasında kalıcı nörolojik sekel ve ölüm açısından prognostik değeri birçok çalışma ile kanıtlanmıştır (14,15). İdeal olan, şüpheli nöbetleri olan yenidoğanlarda video monitörizasyonu ile birlikte uzun cEEG çekimidir (7). Ancak standart klinik uygulamalarda genellikle cEEG çekimi 30-60 dakika ile sınırlıdır.…”

“…Bununla birlikte elektrografik yenidoğan nöbetlerinin çoğu subkliniktir. Serebral aktivitenin sürekli monitörizasyonu; serebral hasarın derecesi ve prognozun değerlendirilmesine, nöbet aktivitesi ve tedaviye yanıtın monitörize edilmesine katkıda bulunabilir (4)(5)(6)(7). Ayrıca nöroprotektif tedavi için uygun olan yenidoğanların erken dönemde belirlenmesine yardımcı olur (8,9).…”