Change over time in internal cerebral vein pulsation in premature infants at risk of intraventricular hemorrhage.

BACKGROUND: Prolonged continuation of augmented internal cerebral vein (ICV) pulsation may be related to the development of premature intraventricular hemorrhage (IVH). However, the characteristics of ICV flow patterns in premature infants are unclear. AIM: To investigate the changes over time in ICV pulsation in premature infants at risk of IVH. STUDY DESIGN: A 5-year retrospective observational study of a single-center trial. SUBJECTS: In total, 112 very-low-birth-weight infants with gestational age of ≤32 weeks. OUTCOME MEASURES: ICV flow was measured every 12 h until 96 h after birth and thereafter on days 7, 14, and 28. The ICV pulsation index (ICVPI), which is a ratio of the minimum/maximum speed of ICV flow, was calculated. We recorded longitudinal ICVPI change and compared ICVPI among three groups classified according to gestational age. RESULTS: ICVPI started declining after day 1 and reached the minimum median value in 49-60 h after birth (1.0 during 0-36 h, 0.9 during 37-72 h, and 1.0 after 73-84 h). ICVPI was significantly lower during 25-96 h than during 0-24 h and on days 7, 14, and 28. ICVPI in the 23-25-week group was significantly lower between 13-24 h and day 14 than that in the 29-32-week group, and the same was observed for the 26-28-week group between 13-24 h and 49-60 h. CONCLUSIONS: ICV pulsation was affected by time after birth and gestational age, and this ICVPI fluctuation may reflect a postnatal circulatory adaptation.

Changes in Internal Cerebral Vein Pulsation and Intraventricular Hemorrhage in Extremely Preterm Infants.

OBJECTIVES: This study aimed to investigate the relationship between internal cerebral vein (ICV) pulsation and intraventricular hemorrhage (IVH) and to identify the cut-off values that predict IVH. We hypothesized that the severity of ICV flow pulsations was related to IVH severity. STUDY DESIGN: In this prospective observational study, ICV flow was measured in 61 extremely preterm infants using ultrasonography at every 12 hours until 96 hours after birth and on days 7, 14, and 28. The ICV pulsation index (ICVPI = minimum/maximum ICV speed) was calculated and compared among the groups determined by Papile's IVH classification. The ICVPI cut-off values for IVH were determined by receiver operating characteristic curve analysis. RESULTS: Compared with those in the no IVH (NIVH) group (n = 51), the ICVPI median values in the severe IVH (SIVH; grades 3 and 4) group (n = 5) were lower at 25 to 96 hours and on day 7, whereas those in the mild IVH (MIVH; grades 1 and 2) group (n = 5) were lower at 37 to 60 hours. All SIVH events were initially detected within 60 hours after birth. The ICVPI cut-off values for SIVH were 0.92 at 13 to 24 hours, 0.42 at 25 to 36 hours, 0.58 at 37 to 48 hours, and 0.55 at 49 to 60 hours. Infants whose ICVPI values were below the cut-off value ≥3 times between 13 and 60 hours had a significantly higher SIVH incidence than those whose ICVPI values were below the cut-off value ≤2 times (57.1 vs. 1.9%, p < 0.001). CONCLUSION: Our results indicate that SIVH had sustained pronounced internal cerebral vein pulsations and that the ICVPI values may help predict SIVH. Further research on strategies to decrease venous pressure for IVH prevention is needed. KEY POINTS: · IVH preterm infants had sustained ICV pulsations.. · ICV flow in SIVH pulsated stronger.. · ICVPI fluctuation implies postnatal adaptation.. · We newly defined ICVPI to predict SIVH..