Thrombinaemia and Hematological Changes Induced in Dogs by the Artificial Kidney

The aim of the investigation was 1) to trace the chronological sequence of coagulation events and haematological changes induced by the artificial kidney and the reaction of the living organism; and 2) to study the influence of various drugs.

Group A, non-treated: in the venous blood factor V activity and fibrinopeptide A, generated in vitro, reached maximal values at 15 min. At 10-15 min fibrinomonomers were detected. From 15 min onwards FDP appeared. Granulocyte and platelet counts reached very low values at 10-15 min. The concentration of serotonin (5HT) was maximal at 10—15 min.

Group B : heparin and coumarin prevented thrombin activity. However, they did not inhibit the initial fall of leucocytes and platelets. Release of 5HT did not occur when no thrombin activity was detected.

Group C, treated with Acetylic Salicylic Acid (ASA), sulfinpyrazon, dipyridamol in combination with ASA, polyphloretinphosphate : thrombin generation was postponed to a small degree. However, the initial loss of leucocytes and platelets was not diminished. The release of 5HT was reduced.

In all three groups the manifestations of thrombin activity were much less pronounced in the arterial line indicating a clearing mechanism in the body. The FDP values in the arterial blood were not different from those on the venous side. The initial decrease of leucocyte and platelet counts, especially in the arterial side suggests trapping in the body. Moreover, the arterial-venous difference in platelet counts indicates retention of platelets in the extracorporeal circuit. The drugs used prevented or diminished generation of thrombin. To influence the initial decrease in leucocyte and platelet counts attention should be directed more to the properties of the different elements of an artificial kidney than to the blood components.