Feline caudal vena cava to aorta ratio reference interval

Area of Science:

• Veterinary Ultrasound
• Cardiovascular Physiology
• Diagnostic Imaging

Background:

• Assessing intravascular volume status is crucial in feline medicine.
• The caudal vena cava to aorta (CVC:Ao) ratio is a potential non-invasive indicator.
• Establishing reliable reference intervals is necessary for clinical application.

Purpose of the Study:

• To ultrasonographically evaluate the CVC:Ao ratio in healthy, conscious cats.
• To generate reference intervals for the CVC:Ao ratio.
• To identify optimal examination sites with minimal observer variability.

Main Methods:

• Ultrasound examinations were performed on 42 healthy, conscious cats.
• Two operators assessed four sites: subxiphoid, hepatic intercostal, hepatorenal, and iliac bifurcation.
• Each site's ease of visualization and vessel ratio variability were recorded.

Main Results:

• Reference intervals for the CVC:Ao ratio were established at all four sites.
• The hepatorenal (0.8-1.41) and iliac bifurcation (0.75-1.2) sites were easiest to visualize.
• Significant intra- and inter-observer variability was noted across all sites.

Conclusions:

• Ultrasonographic CVC:Ao ratio assessment is possible in cats.
• The hepatorenal and iliac bifurcation sites appear most practical for measurement.
• Further research is needed to validate CVC:Ao ratio utility in feline disease states.