Relationship between systemic blood flow, blood pressure, inotropes, and aEEG in the first 48 h of life in extremely preterm infants

BACKGROUND: Significant hemodynamic changes occur immediately after birth in preterm infants. Amplitude-integrated electroencephalography (aEEG) provides a method of assessing brain activity in sick neonates; however, the relationship among systemic blood flow, blood pressure (BP), and aEEG is not clear. METHODS: Quantitative measures of aEEG continuity and amplitude were correlated with superior vena cava (SVC) flow, right-ventricular output (RVO), and BP at 12, 24, and 48 h in 92 infants born at <29 wk gestation. RESULTS: SVC flow, RVO, BP, aEEG amplitude, and EEG continuity all increased from 12 to 48 h. SVC flow at 12 h, but not 24 or 48h, was significantly associated with aEEG amplitude after adjustment for gestational age (GA) and severity of illness markers (r(2) = 0.21, P = 0.004). RVO and BP showed less consistent associations with aEEG parameters. Infants receiving inotropes at 12h, including those in whom cardiovascular parameters had normalized, had significantly lower aEEG amplitude (P < 0.01) and EEG continuity at the 10, 25, and 50 mu V levels (P < 0.01) at 12, 24, and 48h than neonates who were not receiving inotropes. CONCLUSION: aEEG measurements in the first 48 h of life are related to SVC flow and treatment with inotropes at 12 h of life in extremely preterm infants.