Noninvasive and continuous monitoring of cerebral blood flow (CBF) responses to intermittent hypoxia (IH) in neonatal rats (Conference Presentation)

Intermittent hypoxia (IH) may result in hypoxic/ischemic stresses on neonatal brains. We have developed a novel wearable, fiber-free, diffuse speckle contrast flowmetry (DSCF) probe for continuous monitoring of cerebral blood flow (CBF) variations during IH. A controlled experiment in neonatal rats was performed to evaluate the DSCF in assessing CBF variations during IH. A miniaturized probe was affixed to neonatal rats (3-5 days old) under 1% Isoflurane anesthesia. The IH group (n = 4) received 10 cycles of 2-minute 8% O2 in N2 and 2-minute 100% O2 daily for 3 days, while the sham group (n = 3) underwent 13-minute normoxic monitoring. The sham group showed small CBF variations over 3 days. Conversely, the IH group demonstrated remarkable CBF increases (13.67% ± 7.55%, 24.53% ± 12.42%, 15.14% ± 12.47%) along with brain injuries. We are currently testing the DSCF for cerebral monitoring of neonatal piglets and human neonates during IH.