National Conference of Undergraduate Research (NCUR)April 10th, 2024, Long Beach Convention & Entertainment Center, Long Beach, CA
Podium Presentation
Title: Extent of Vascular Damage at Varying Degrees of Stretch in Hypoxic Neonatal Brachial Plexus
Abstract:Neonatal brachial plexus palsy (NBPP) is an injury to brachial plexus (BP) nerves due to over-stretching during complex birthing scenarios. NBPP has an incidence of 1-4 cases per 1000 live births. Neonatal hypoxia can also occur as a result of obstetric complications, such as disrupted blood supply due to umbilical cord compression. Characterizing the extent of vascular damage of hypoxic neonatal BP at varying degrees of stretch can further the understanding of the injury thresholds of NBPP. All procedures were approved by the Institutional Animal Care and Use Committee. 15 neonatal piglets (3-5 days old) were anesthetized and exposed to FiO2 of 7% for 1 hour to induce hypoxia and re-perfused to FiO2 of 21%. Immediately post hypoxia, the BP was exposed and stretched at a rate of 500 mm/min to predetermined low- (<15%) and high- (>15%) strains. BP nerves were harvested and OCT-embedded. Ten-µm-thick serial longitudinal sections were stained with Hematoxylin-Eosin (H&E). Using the Olympus BX53 microscope, stitched stained H&E images (10x) of the entire nerve were obtained. Using a custom MATLAB script, regions of interest (ROI) were identified for each nerve and scored for vascular damage on a scale of 0-2 (0-no damage, 1-torn vessel, 2-scattered blood cells) by an independent-blinded observer. Based on our modified scoring system, preliminary results show that vascular damage increased with increasing stretch injury such that no (n=30), low (n=33), and high (n=30) stretch ROIs reported average scores of 0.6±0.3, 1.0±0.3, and 1.1±0.3 respectively. Similar degrees of damage were observed in the central and peripheral regions of the stretched nerve. This ongoing study is the first to characterize vascular damage of hypoxic neonatal BP nerves with respect to varying degrees of stretch and helps further our understanding of NBPP.
Podium Presentation
Title: Extent of Vascular Damage at Varying Degrees of Stretch in Hypoxic Neonatal Brachial Plexus
Abstract:Neonatal brachial plexus palsy (NBPP) is an injury to brachial plexus (BP) nerves due to over-stretching during complex birthing scenarios. NBPP has an incidence of 1-4 cases per 1000 live births. Neonatal hypoxia can also occur as a result of obstetric complications, such as disrupted blood supply due to umbilical cord compression. Characterizing the extent of vascular damage of hypoxic neonatal BP at varying degrees of stretch can further the understanding of the injury thresholds of NBPP. All procedures were approved by the Institutional Animal Care and Use Committee. 15 neonatal piglets (3-5 days old) were anesthetized and exposed to FiO2 of 7% for 1 hour to induce hypoxia and re-perfused to FiO2 of 21%. Immediately post hypoxia, the BP was exposed and stretched at a rate of 500 mm/min to predetermined low- (<15%) and high- (>15%) strains. BP nerves were harvested and OCT-embedded. Ten-µm-thick serial longitudinal sections were stained with Hematoxylin-Eosin (H&E). Using the Olympus BX53 microscope, stitched stained H&E images (10x) of the entire nerve were obtained. Using a custom MATLAB script, regions of interest (ROI) were identified for each nerve and scored for vascular damage on a scale of 0-2 (0-no damage, 1-torn vessel, 2-scattered blood cells) by an independent-blinded observer. Based on our modified scoring system, preliminary results show that vascular damage increased with increasing stretch injury such that no (n=30), low (n=33), and high (n=30) stretch ROIs reported average scores of 0.6±0.3, 1.0±0.3, and 1.1±0.3 respectively. Similar degrees of damage were observed in the central and peripheral regions of the stretched nerve. This ongoing study is the first to characterize vascular damage of hypoxic neonatal BP nerves with respect to varying degrees of stretch and helps further our understanding of NBPP.