AUTHOR=Diaz Devon M. , Orton E. Christopher , de Rezende Marlis L. , Zersen Kristin , Guillaumin Julien 

TITLE=Assessment of microcirculation variables and endothelial glycocalyx using sidestream dark field videomicroscopy in anesthetized dogs undergoing cardiopulmonary bypass

JOURNAL=Frontiers in Veterinary Science

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2023.1189738

DOI=10.3389/fvets.2023.1189738

ISSN=2297-1769

ABSTRACT=<sec id="sec1"><title>Introduction</title><p>To evaluate microcirculation and endothelial glycocalyx (eGC) variables using sidestream darkfield (SDF) videomicroscopy in canine cardiopulmonary bypass (CPB).</p></sec><sec id="sec2"><title>Methods</title><p>Dogs undergoing CPB for surgical correction of naturally-occurring cardiac disease were prospectively included. Variables collected included patient demographics, underlying cardiac disease, red blood cell flow (Flow), 4-25 μm vessel density (Density), absolute capillary blood volume (CBVabs), relative capillary blood volume (CBVrel) and eGC width assessed by perfused boundary region (PBR). Anesthetized healthy dogs were used as control. Microcirculation and eGC variables were compared at baseline under anesthesia (T0), on CPB prior to cross clamping (T1), after cross clamp removal following surgical correction (T2) and at surgical closure (T3).</p></sec><sec id="sec3"><title>Results</title><p>Twelve dogs were enrolled, including 10 with a complete dataset. Median Flow was 233.9, 79.9, 164.3, and 136.1 μm/s at T0, T1, T2, and T3, respectively, (<italic>p</italic> = 1.00). Median Density was 173.3, 118.4, 121.0 and 155.4 mm/mm<sup>2</sup> at T0, T1, T2, and T3, respectively, (<italic>p</italic> = 1.00). Median CBVabs decreased over time: 7.4, 6.6, 4.8 and 4.7 10<sup>3</sup>μm<sup>3</sup> at T0, T1, T2, and T3, respectively, (<italic>p</italic> &lt; 0.01). Median CBVrel increased over time: 1.1, 1.5,1.1, and 1.3 10<sup>3</sup>μm<sup>3</sup> at T0, T1, T2, and T3, respectively, (<italic>p</italic> &lt; 0.001). Median PBR increased over time: 1.8, 2.1, 2.4, 2.1 μm at T0, T1, T2, and T3, respectively, (<italic>p</italic> &lt; 0.001). Compared to control dogs (<italic>n</italic> = 8), CPB dogs had lower CBVabs at T0.</p></sec><sec id="sec4"><title>Conclusion</title><p>Alterations in eGC thickness and microvascular occur in dogs undergoing CPB for naturally-occurring cardiac disease.</p></sec>