Background and Aims Echocardiography-derived low superior vena cava flow (SVCF) associates intraventricular haemorrhage, neurodisability and death. The weaknesses of the method relate to its variability. We aim to explore the relationship between two SVCF cut-off values to define PPS in LBWI and the patients’ short-term neonatal co-morbidities.
Methods One hundred LBWI [27.4 (2) wks; 1014 (316) g] who reached illness score below threshold, underwent early (< 12h) and serial echocardiography for the first 96hs after birth. The primary outcome was low SVCF prevalence according to two thresholds: < 41 ml/k/min and [< 41 ml/k/min + SVCF repeatability index (RI)](RI is twice the standard deviation of the differences divided by the mean of all the measures). Secondary outcomes were short-term neonatal clinical outcomes in relation to SVCF status.
Results SVCF< 41 ml/k/min prevalence was 30% and was associated with immaturity (p=0.02), corioamnionitis (0.007), advanced resuscitation at birth (0.004), lower Apgar scores (p<0.01) and postnatal ischemic events (bowel perforation or arterial vasospasm) (p=0.002). At SVCF < 51 ml/k/min (41 ml/k/min + repeatability index) cut-off value, the PPS prevalence was 50%; in addition to the above-mentioned co-morbidities trends showed an association between PPS and combined adverse outcome (death or intracranial haemorrhage).
Conclusions Low SVCF is highly prevalent in the sick LBWI during the early postnatal period. The association of low SVCF with ischemic events and adverse outcome supports this biomarker as an indicator of PPS.
Disclaimer No conflict of interest. Study supported by the Spanish Health Ministry, SAS/2481/2009, the SAMID network (RD08/0072/0018).