Blood cells and coagulation during experimental lung insufficiency in dogs

Thromboembolism of minor vessels in the lungs is almost constantly seen in posttraumtic lung insufficiency. Many investigators consider it as the primary factor in the pathogenesis of this condition. The present paper deals with screening of the coagulation system as part of a more extended project also investigating changes in the fibrinolytic system and the kallikrein-kinin system. The data are also to be compared with morphological findings during the development of experimental posttraumatic lung insufficiency. The experimental syndrome was evoked in Labrador retriever dogs by haemorrhagic hypotension combined with clamping of the portal triad. The surgical procedure was extended to additional thoracotomy in one group of dogs. Group I, without thoracotomy, were followed for 12 hours. Group II, with thoracotomy, were followed until they succumbed (3-14 hours). Thrombotest (TT) showed a steady prolongation of clotting time in both groups, whereas Cephotest did not reveal any alterations, except for a significant prolongation in group II just before collapse. Fibrinogen was markedly reduced in both groups. Platelets and leucocytes were significantly reduced, but only in group II. It is concluded that the present data are indicative of disseminated intravascular coagulation. The involvement of the intrinsic coagulation system is questioned.