Segmental auxiliary liver transplantation in dogs: a search for an ideal graft--illusion or reality?

Segmental auxiliary liver transplantation (SALT) has been carried out in 13 mongrel dogs to assess the possibility of a certain size of liver segment to accept without sequelae the total splanchnic and arterial blood normally diverted to the liver of the host. Prednisone (1 mg/daily) and azathioprine (2 mg/kg daily) were used as immunosuppression. Five dogs died during the first hours after the operation. Three because of technical failure and two of acute portal hypertension secondary to total portal and arterial blood diversion in dogs with liver segments of 195 +/- 49 g as a result of overloading of the graft. The remaining 8 dogs were divided into: 4 dogs into which a liver segment (195 +/- 49 g) was transplanted (group A) and 4 dogs in which a liver segment (385 +/- 85 g) was used (group B). Partial portal and total arterial blood diversion in group A dogs was not associated with portal hypertension but resulted in poor function of the graft and in poor survival. In contrast, the graft in group B dogs was able to cope with both total or partial portal blood and with a normal arterial blood diversion. Infection and graft rejection prohibited long-term survival (8-28 days). Data from this study support the view that the present technique of SALT with a graft corresponding to 300-400 g in mongrel dogs of about 30 kg is a potential alternative as temporary liver support in the diseased animal.