[Changes in the pump function of the right ventricle during "pressure-autotransfusion" with citrate and heparin (author's transl)].

Nine anaesthetized, splenectomized dogs, heparinized with 300 IU/kg bodyweight heparin i.v. had one tenth of their total blood volume returned to them by autotransfusion under maximum pressure with the Bentley-system. For the "Heparin"-autotransfusion (n = 49) 1:5 0,9% NaCl was added to the blood; whilst for the "Citrate"-autotransfusion 1:5 ACD-B(n = 28) or CPD (n = 30) stabilisor was added. Autotransfusion was performed as follows: Heparin-ACD-B- Heparin-DPD- Heparin-ACD-B etc. The pump function of the right ventricular myocardium was measured by the force of contraction (PRV, IP, SV, T1) as well as by criteria of contractility (dp/dtmax, VCEmax, KI1, KI2). Immediately after acute bleeding a reduction of the force of contraction to 50% was seen, but the contractility remained unchanged. During the maximum pressure autotransfusion of the blood the force of contraction consistently increased irrespective of the anticoagulant used. The contractility remained unchanged. In the following phase the force of contraction and the contractility normalised when heparin was employed, whilst when citrate was used there was a reduction of the force of contraction and of the contractility corresponding with the different dose of citrate of ACD-B and CPD. This short phase was followed by spontaneous stabilisation of the circulation. The force of contraction and the contractility returned to normal when heparin and ACD-B were employed, whilst a reduction of these criteria occurred when CPD was used. From these findings, the scheme of anticoagulation for citrate under clinical conditions should be modified by a prior injection of 2,000-3,000 IE of heparin i.v. and the addition of citrate in the ratio of 1:7 for ACD-B or 1:8 for CPD.