Reference Values for Amplitude-Integrated EEGs in Infants From Preterm to 3.5 Months of Age

Abstract

Reference values of aEEG amplitudes were obtained for infants with a wide range of PMAs and constituted the basis for the quantitative assessment of aEEG changes with maturation in neonates and young infants. The normative amplitudes of aEEG margins, especially of the lower margin in quiet sleep, are recommended as a source of reference data for the identification of potentially abnormal aEEG results.

Systematic characterization of amplitude-integrated EEG signals for monitoring the preterm brain

“…The increasing adoption of the aEEG method in the neonatal intensive care unit is reflected by the growing number of studies published during the past decade, although these still do not match the knowledge that was gained in term-born infants over the same period of time (8)(9)(10). Efforts have been made to define normative values and changes in aEEG parameters with respect to gestational age (GA) and postmenstrual age (PMA) (11)(12)(13)(14)(15), and recently, integrative studies correlating aEEG with various clinical parameters have been published (16)(17)(18). These examples demonstrate that the concept of aEEG monitoring can be very useful in preterm infants.…”

Calculation of compact amplitude-integrated EEG tracing and upper and lower margins using raw EEG data

“…The main reason to select nonparametric measures such as the median and percentiles is that they are noise-proof and, thus, insensitive to outliers with extremely high amplitudes. Moreover, the amplitude of the aEEG is not normally distributed, such that nonparametric statistics are more suitable [3,5,20,21].…”

“…The proposed algorithm has been employed to analyze aEEG data from a large population of infants, and a related article was published in a top journal of pediatrics [20]. Although our clinical and research practice has verified that the algorithm and the calculation parameters shown in Figure 4 are robust in various environment, some of the parameters may need to be adapted using a calibrated method (i.e., as shown in Section 3) if raw EEG data are collected under very special circumstances.…”

“…The average postmenstrual age, calculated by adding the weeks of gestational age to the postnatal age, was 42.1 ± 6.5 weeks (range: 31 -69 weeks). The infant aEEG characteristics are found in [18,20]. Some representative aEEG tracings in the testing dataset are displayed in the left column of Figure 5.…”

Differences in amplitude among electrode locations on amplitude-integrated electroencephalograms in preterm infants

“…For quantitative analyses, we used the following method, modified from the previously reported method of Zhang et al (20). We outputted the UMA and the LMA data from all seven channels for the entire record as a text file from the NicoletOne Monitor, with a time resolution of 1 s. Then the data were divided into epochs of 15 s, and the maximum of UMA and minimum of LMA were extracted in accordance with the standard clinical aEEG trace.…”