Developing a small animal model of extracorporeal circulation.
To identify nonthrombogenic devices to be used in extracorporeal circulation (ECC), an efficient, small animal model is required. Initially, a venovenous (VV) model in rabbits was designed for this purpose and was a good representation of ECC. Technical difficulties in the VV model led to the development of a more simplistic arteriovenous (AV) model. Anesthetized, tracheotomized, 3-kg rabbits were used for both models. Circuits were constructed of PVC tubing. The VV model used 8-Fr umbilical artery catheters for both drainage and reinfusion, and the AV model used a 14-GA angiocatheter for carotid artery access and a 10-Fr thoracic catheter for venous access. The AV model included a chamber to mimic oxygenator or filter modeling. Hourly measurements included blood gases, platelet counts, and fibrinogen levels for the 4-hour studies. The VV ECC groups demonstrated platelet consumption like that seen in the clinical arena. The AV model demonstrated the same with or without additional surface area within the chamber. The AV model was deemed to be superior due to its simplicity, ability for filter modeling, and decrease in intensive monitoring. However, both models are excellent designs for nonthrombogenic surface testing.
Skrzypchak
Amy M
AM
Department of General Surgery, Extracorporeal Life Support Laboratory, University of Michigan Medical Center, Ann Arbor, MI 48109-0243, USA.
Miskulin
Judiann
J
Bartlett
Robert H
RH
Annich
Gail M
GM
D000818:Animals; D001166:Arteriovenous Shunt, Surgical / Q000379:methods*; D001784:Blood Gas Analysis; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D002339:Carotid Arteries / Q000601:surgery; D020099:Coated Materials, Biocompatible / Q000494:pharmacology; D005112:Extracorporeal Circulation / Q000295:instrumentation* / Q000379:methods; D005340:Fibrinogen / Q000032:analysis / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D006439:Hemodynamics / Q000187:drug effects; D007457:Iodine Radioisotopes; D007601:Jugular Veins / Q000601:surgery; D023421:Models, Animal; D015539:Platelet Activation / Q000187:drug effects; D010976:Platelet Count; D011817:Rabbits; D016019:Survival Analysis; D013927:Thrombosis / Q000517:prevention & control; D013997:Time Factors; D014140:Tracheotomy
D020099:Coated Materials, Biocompatible; D007457:Iodine Radioisotopes; D005340:Fibrinogen