RESUMO
A traditional bypass pattern applied in hepatectomy (venous return in superior vena cava system) is frequently attended by blood congestion in cranial veins. The study objective is the maintenance of hemodynamic indices in normal physiological ranges via application of the new bypass scheme in the experimental model of the anhepatic period. 12 rabbits of Chinchilla breed were involved in the experiments, with weight ranging between 3,0-3,5 kg, which were divided into three groups (with 3 animals in each): I control group - hepatectomy under the condition of non-compulsory liver bypass with the return of the venous flow in brachiocephalic vein. II group - hepatectomy with the compulsory bypass, with an in-take of blood in the apparatus and injection in the brachiocephalic vein. III group - hepatectomy via non-traditional method of compulsory bypass in suprahepatic vena cava. The outcomes of the experiments indicated that blood congestion in cranial venous system occurred only in I and II groups, which was verified by the pressure rise (5,9+/-1,2 mmHg and 4,7+/-0,5 mmHg, respectively) and diminished blood flow rate (3,0+/-1,8 ml/min and 2,0+/-0,7 ml/min) in external jugular vein. These indices corresponded with the levels of 0,6+/-0,2 mm Hg and 9,0+/-2,5 ml/min respectively in the III group. Application of the artificial, compulsary bypass circuit has been established to be reasonable in anhepatic period, for achieving the blood return to the heart through portal vein and from the lower parts of the body. During blood return in suprahepatic portion of vena cava, the congestion in cranial venous system is prevented. Maintenance of the pressure and volume indices between normal physiological limits in venous system provides the opportunity of safe prolongation of the anhepatic period.
