Early low cardiac output is associated with compromised electroencephalographic activity in very preterm infants

Low cerebral blood flow in preterm infants has been associated with discontinuous electroencephalography (EEG) activity that in turn has been associated with poor long-term prognosis. We examined the relationships between echocardiographic measurements of blood flow, blood pressure (BP), and quantitative EEG data as surrogate markers of cerebral perfusion and function with 112 sets of paired data obtained over the first 48 h after birth in 40 preterm infants (24-30 wk of gestation, 510-1900 g at delivery). Echocardiographic measurements of right ventricular output (RVO) and superior vena caval (SVC) flow were performed serially. BP recordings were obtained from invasive monitoring or oscillometry. Modified cotside EEGs were analyzed for quantitative amplitude and continuity measurements. RVO 12 h after birth was related to both EEG amplitude at 12 and 24 h and continuity at 24 h. Mean systemic arterial pressure (MAP) at 12 and 24 h was related to continuity at 12 and 24 h after birth. Multiple regression analyses revealed that RVO at 12 h was related to median EEG amplitude at 24 h and diastolic BP at 24 h was related to simultaneous EEG continuity. In addition, at 12 h, infants in the lowest quartile for RVO measurements (<282 mL/kg/min) had lower EEG amplitude and those in the lowest quartile for MAP measurements (<31 mm Hg) had lower EEG continuity. These results suggest a relationship between indirect measurements of cerebral perfusion and cerebral function soon after birth in preterm infants.