Data_Sheet_4_Rapid Patient-Side Evaluation of Endothelial Glycocalyx Thickness in Healthy Sedated Cats Using GlycoCheck® Software.docx

The endothelial glycocalyx (EG) determines transvascular fluid fluxes, and influences inflammation, coagulation, and capillary blood flow. The GlycoCheck® software calculates EG thickness using sidestream dark field videomicroscopy recordings. This method has not been evaluated for use in cats. The aim of the present study was to evaluate the use of GlycoCheck® for estimating EG thickness in healthy cats, and to investigate the variability of EG thickness in this population. One hundred and one healthy research-purposed cats were included in the study. The cats were sedated, and a handheld videomicroscope, connected to GlycoCheck® software, was used to evaluate the sublingual microvasculature. The parameters measured included perfused boundary region (PBR, an indirect measurement of EG thickness) in vessels between 5 and 25 μm in diameter, valid vessel density, percentage red blood cell filling, and median red blood cell column width. Heart rate, respiratory rate, pulse oximetry and oscillometric blood pressure readings were also recorded. There were 35 neutered male cats, 11 intact males, 38 neutered females, and 17 intact females. The average age was 63 months (range, 11–160 months). Tolerance intervals for PBR (vessel diameter 5–25 μm) were 1.89–3.00 μm (95% CI, lower limit 1.76–2.04, upper limit 2.83–3.13 μm); for valid vessel density were 73.33–333.33 μm/mm2 (95% CI, lower limit 77.00–99.33, upper limit 312.67–350.33 μm/mm2); for percentage red blood cell filling were 59.85–85.07% (95% CI, lower limit 58.97–63.33, upper limit 83.07–88.20 %); and for median red blood cell column width were 5.63–8.59 μm (95% CI, lower limit 5.28–6.07, upper limit 8.14–9.51 μm). There was a negative association between median red blood cell column width and body weight (p = 0.007). The median red blood cell column was significantly wider in intact females when compared to spayed females (p = 0.033). The GlycoCheck® analysis was easily performed in healthy sedated cats. Clinical variables did not have an effect on the EG thickness. These results suggest that this technique could be valuable for evaluation of the EG and microvascular parameters in cats.

内皮糖萼（endothelial glycocalyx, EG）可调控跨血管液体流动，并对炎症、凝血及毛细血管血流产生影响。GlycoCheck®软件可通过侧流暗场视频显微成像记录数据计算EG厚度，但该方法尚未在猫类中开展评估。

本研究旨在评估GlycoCheck®用于估算健康猫EG厚度的可行性，并探究该群体中EG厚度的变异情况。本研究共纳入101只科研用健康猫。

对受试猫实施镇静处理后，使用连接至GlycoCheck®软件的手持式视频显微镜评估其舌下微脉管系统。本次检测的参数包括：直径5~25 μm血管内的灌注边界区（perfused boundary region, PBR，EG厚度的间接检测指标）、有效血管密度、红细胞充盈百分比及红细胞柱中位宽度。同时记录受试猫的心率、呼吸频率、脉搏血氧饱和度及示波血压读数。

受试猫群体构成如下：去势公猫35只、未去势公猫11只、去势母猫38只、未去势母猫17只；平均年龄为63月龄（范围11~160月龄）。

灌注边界区（血管直径5~25 μm）的耐受区间为1.89~3.00 μm（95%置信区间，下限1.76~2.04 μm，上限2.83~3.13 μm）；有效血管密度的耐受区间为73.33~333.33 μm/mm²（95%置信区间，下限77.00~99.33 μm/mm²，上限312.67~350.33 μm/mm²）；红细胞充盈百分比的耐受区间为59.85%~85.07%（95%置信区间，下限58.97%~63.33%，上限83.07%~88.20%）；红细胞柱中位宽度的耐受区间为5.63~8.59 μm（95%置信区间，下限5.28~6.07 μm，上限8.14~9.51 μm）。

红细胞柱中位宽度与体重呈负相关（p=0.007）。未去势母猫的红细胞柱中位宽度显著高于去势母猫（p=0.033）。

在镇静的健康猫中可轻松完成GlycoCheck®分析。临床变量对EG厚度无显著影响。上述结果表明，该技术有望用于猫类EG及微脉管参数的评估。