- Shih A, Giguere S, Vigani A, Shih R, Thuramalla N, Bandt C. Determination of cardiac output by ultrasound velocity dilution in normovolemia and hypovolemia in dogs. Vet Anaesth Analg. 2011;38:279-85 pubmed publisher..88 (p < 0.0001). When compared to lithium dilution, the UDCO technique is a viable method for measuring cardiac output in a model of normovolemia and hypovolemia in dogs. ..