{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T13:04:58Z","timestamp":1789736698079,"version":"4.0.1"},"reference-count":25,"publisher":"American Veterinary Medical Association (AVMA)","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["javma"],"published-print":{"date-parts":[[2026,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To determine the feasibility of measuring caudal vena cava (CVC) and aorta size in non\u2013contrast-enhanced CT scans of rabbits, variations in size and circularity depending on anatomical location, factors and conditions affecting the CVC-to-aorta (CVC:Ao) ratios, and changes of CVC:Ao ratios in hemodynamically unstable rabbits.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This retrospective cohort study included consecutive client-owned rabbits that presented to the Cornell University Hospital for Animals between June 2022 and October 2024 and received an abdominal CT. Forty-nine CT scans from 46 individual rabbits were included. The CVC:Ao ratio was determined similarly to dogs. Hemodynamically instability was assessed by 2 independent blinded investigators.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>100% (95% CI, 92.8% to 100%) and 87.8% (95% CI, 75.2% to 95.4%) of the thoracic and abdominal CVC:Ao ratios, respectively, were measurable. Several factors were associated with abdominal and thoracic CVC:Ao ratios and their difference, including a higher difference between abdominal and thoracic ratio in rabbits with intestinal obstruction. The abdominal CVC:Ao ratio and the difference between abdominal and thoracic CVC:Ao ratio were significant predictors of hemodynamic instability, with a 6-fold and 8-fold increase in the odds of hemodynamic instability for every additional unit of these ratios and an area under the curve of 0.73 (95% CI, 0.56 to 0.91) and of 0.79 (95% CI, 0.64 to 0.93).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In diseased rabbits, the aorta and CVC are larger and less circular in the thorax than in the abdomen. In hemodynamic unstable rabbits, the thoracic CVC:Ao ratio decreased while the abdominal CVC:Ao ratio increased, likely owing to gastric compression on the vena cava.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical Relevance<\/jats:title>\n                    <jats:p>CVC:Ao ratios can be used as significant predictors of hemodynamic instability in diseased rabbits.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2460\/javma.26.01.0013","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T19:45:55Z","timestamp":1782503155000},"page":"1-9","source":"Crossref","is-referenced-by-count":0,"title":["Caudal vena cava-to-aorta ratio in hemodynamically stable and unstable client-owned rabbits"],"prefix":"10.2460","volume":"264","author":[{"given":"Taylor","family":"Lashlee","sequence":"first","affiliation":[{"name":"Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4539-4298","authenticated-orcid":true,"given":"Christopher R.","family":"Tollefson","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Armi M.","family":"Pigott","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0694-7804","authenticated-orcid":true,"given":"Lauren","family":"Thielen","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Margherita","family":"De Silva","sequence":"additional","affiliation":[{"name":"Clinic for Exotic Animals, Veterinary Specialistic Center, Roma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5203-9765","authenticated-orcid":true,"given":"Nicola","family":"Di Girolamo","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"issue":"2","key":"ref1","series-title":"Vet Clin North Am Exot Anim Pract","first-page":"379","article-title":"Assessment and care of the critically ill rabbit","volume":"19","author":"Huynh M","year":"2016","unstructured":"Huynh M, Boyeaux A, Pignon C. 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