[End-to-side mesenteric caval in children - significance of blood flow physics in defining the surgical procedure preoperatively (author's transl)].

Elevated blood pressure of the portal circulation in children may be lowered to defined levels by end-to-side shunting of the mesenteric and the portal vein. The question is, whether an optimal geometry of the ellipsoid anastomosis can be calculated preoperatively. A simplified model of the shunt system is presented using electric and hydraulic analogs of the real blood flow physics. It is not taken into account in this model, that there are two capillary beds connected in series in the portal circulation, which both exhibit high blood flow resistance. Shunt resistance as being calculated on the basis of this model in 6 children, and real shunt resistance as being measured in these patients intraoperatively actually turned out to be in the same order of magnitude inspite of the handicaps of the model. Thus to our opinion the calculations presented are suited to determine preoperatively the optimal geometry of an ellipsoid shunt anastomosis intended to lower blood pressure in the portal circulation to levels as desired.