Prediction of Intraventricular Hemorrhage Using Echocardiography and Near Infrared Spectroscopy

The overall objective is to conduct a large, adequately powered prospective cohort study to investigate the utility of combined hemodynamic assessment using NIRS and ECHO for early identification of ELGANs at risk of developing moderate-severe IVH, and to establish clinically translatable prediction models. The specific primary aim is to examine the discriminating characteristics of NIRS-derived parameters (CrSO2 and cerebral oxygenation index \[COIx, values \>0.5 indicate altered cerebral autoregulation\]) at 12, 18, 24, 30, 36, 42 and 48 hours of age, individually and in combination, for identifying ELGANs who subsequently develop moderate-severe IVH. The postnatal age where NIRS may best identify at-risk ELGANs is unknown and identifying these infants early within 48 hours of age may maximize its impact for employing neuroprotective strategies. The secondary aims are: 1. To examine if adding ECHO parameters of systemic blood flow (left ventricular output \[LVO\], superior vena cava \[SVC\] flow and PDA size) and patient demographics can improve the discriminating characteristics of NIRS and generate relevant clinical prediction models. 2. To gain mechanistic insights into pathophysiology of moderate-severe IVH, by examining associations between significant abnormalities on NIRS, as identified and ECHO markers which may impact cerebral perfusion and oxygen delivery (PDA and its size, LVO, right ventricular output and left ventricular ejection fraction). This will be novel information as potential mechanisms governing low CrSO2 or altered autoregulation in ELGANs are not known and can potentially inform future clinical preventative strategies and help design interventional trials.