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

Abstract

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.

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

“…With a median of 1.80 μm, there were no statistically significant difference compared to a median of 2.37 μm in control dogs. The PBR in our control dogs is similar to values found in healthy anesthetized dogs and healthy sedated cats in other studies ( 24 , 25 ). Our study also found that baseline PBR for dogs were comparable to studies in infants (approximately 2.5 μm), and human adults (approximately 2.0–2.2 μm) ( 17 , 18 ).…”

The microvascular endothelial glycocalyx: An additional piece of the puzzle in veterinary medicine

“…Sidestream dark field imaging has been explored for veterinary use. Two studies have applied this methodology in a non-invasive way to measure the eGlx in the sublingual microvasculature of anaesthetised dogs ( Londoño et al, 2018 ) and cats ( Yozova et al, 2021 ). In horses, sidestream dark field video microscopy has been used to assess microvascular perfusion ( Mansour et al, 2021 ), but not the eGlx.…”

A quantitative evaluation of the effect of foreign body obstruction and enterectomy technique on canine small intestinal microvascular health

“…14,16 Use of SDF videomicroscopy with proprietary software has been validated for sublingual interrogation of microvascular health in humans, dogs, and cats in the critical care setting. 17,18 Moreover, use on the jejunum of healthy dogs has previously been described and quantitative parameters established. 19 As far as the authors are aware, use on diseased or devitalized canine intestine has not been reported previously.…”