Hemodynamics of infants with strong fluctuations of internal cerebral vein.

BACKGROUND: There is a high incidence of intraventricular hemorrhage in extremely low-birthweight (ELBW) infants of low gestational age with high-grade fluctuations in the perfusion waveform of the internal cerebral vein. This study investigated changes in the hemodynamic status of ELBW infants during initial strong fluctuations in the perfusion waveform of the internal cerebral vein.

METHODS: We evaluated the perfusion waveform of the internal cerebral vein in 192 ELBW infants from birth, every 8 h for a total of 120 h. Sixty-seven infants had high-grade fluctuations. On the basis of the presence of patent ductus arteriosus (PDA), patients were subdivided into PDA(-) (n = 32) and PDA(+) (n = 35) groups.

RESULTS: During the first high-grade fluctuation, the PDA(-) group had significant increases in systolic, diastolic, and mean blood pressure (P < 0.001 for all). The PDA(+) group did not have significant changes in blood pressure but did have significant increases in the number of interruptions or regurgitations of diastolic renal arterial blood flow (P = 0.04) and end-diastolic left pulmonary arterial flow velocity (P < 0.001), indicating increased left-to-right shunt.

CONCLUSIONS: Blood pressure elevation may underlie fluctuations in the perfusion waveform of the internal cerebral vein and lead to the first high-grade increases during acute management of ELBW infants. When no elevation in blood pressure occurred, hemodynamically significant PDA was considered a potential underlying factor.