A recent thread on the Ferret Adrenal/Insulinoma Mailing List has been the vena cava ligation and the high mortality rates that have been reported with this procedure. Dr. Charles Weiss wrote an explanation of the conditions under which this procedure can be performed safely. Dr. Weiss wrote this post on July 26, 1998, for FML and FAIML readers and their veterinarians. For those of you who are new to the list, Dr. Weiss is in Potomac, Maryland. He is highly respected for his expertise in ferret medicine. VENA CAVA LIGATION I have performed about 10 of these procedures to date. All the ferrets have survived and are doing well. In my opinion vena cava ligation can be a life saving technique which should be performed with select cases. The right adrenal gland in the ferret is normally attached to the vena cava, which makes it a technically difficult surgery. Although difficult, an experienced ferret surgeon usually can perform this procedure without ligating the vena cava, with very good success. I do not feel the vena cava should be ligated routinely, or because the adrenal tumor is "attached" to the vena cava (it is virtually always attached to the vena cava). On occasion we see very large right adrenal tumors which almost completely occlude (obstruct the blood flow through) the vena cava. In these cases the tumor grows over weeks or months slowly occluding more and more of the blood flow through the vena cava. When this occurs over this time frame the body develops collateral circulation (other small new blood vessels that bypass the vena cava). Therefore when the vena cava is almost completely occluded I feel it is usually safe to ligate it in the ferret. The other alternative is closing the ferret up and calling it an inoperable tumor (which is giving the ferret a death sentence). With the option of vena cava ligation virtually all adrenal tumors are operable. This is really a benefit to the patient since even malignant adrenal tumors rarely spread and complete removal is usually curative. When used appropriately I feel this is a life saving technique which has minimal complications. But, it's important to remember that a ferret with a large adrenal tumor is a very ill animal (even if it comes on so slowly that the owners do not notice many symptoms). Although this is a very stoic species which does not always display pain as we do, this is a life threatening condition. In a case like this there are always risks associated with anesthesia and surgery, because it is such a serious condition. In my opinion, in such a case, surgery with vena cava ligation is the best chance to save the patient's life and give the ferret a good quality of life post- operatively. Charles Weiss, DVM [Posted in FML issue 2391]