Antifibrinolytic drugs in the treatment of urinary tract haemorrhage

The fibrinolytic system in man

The existence of a system in the human body capable of inducing the dissolution of endogenous pathologically formed thrombi was appreciated in ancient times. Considered in detail in this article are the data that have elucidated the physiologic regulation of which plasmin formation is dependent on, the plasma concentration of plasminogen, availability of activators of plasminogen in the plasma and surrounding tissue environment, the concentration of naturally present inhibitors, and the existence of fibrin in the circulation. Important in this rapidly progressive scientific discipline is consideration of the factors which control the synthesis of the components of this proteolytic enzyme system. Recently abundant information has indicated that this plasminogen-plasmin proteolytic enzyme system can be utilized therapeutically. Knowledge of the mechanisms of this system has permitted identification of agents that can be exogenously administered to releave thrombotic obstruction to blood flow in the venous (pulmonary emboli, deep vein thrombosis) and arterial (peripheral and central vessels) circulatory systems. Particularly important is the demonstration that thrombolytic agents can directly attack and alleviate the immediate cause of acute myocardial infarction. As a result of the innovations in the present decade, it is evident that the plasminogen system can be advantageously employed to reverse the pathologic effects of all thrombotic diseases.

Tranexamic acid and upper gastrointestinal haemorrhage--a double-blind trial

The efficacy of antifibrinolytic therapy in the management of acute upper gastrointestinal haemorrhage has been investigated in a double-blind clinical trial. Two-hundred patients were studied using tranexamic acid, a potent antifibrinolytic agent. Of these, 103 were in the treatment group and 97 in the control group. Patients were analysed to determine severity of initial blood loss, transfusion requirements, together with the incidence of recurrent bleeding, surgical intervention, and death. Final diagnosis as to the site of bleeding was arrived at using endoscopy, barium studies, and the findings at operation and necropsy. The groups were well matched as regards severity of initial haemorrhage, age, sex, aetiological diagnosis, and precipitating factors. A significant difference was observed in the requirement for surgical intervention to control continuing or recurrent haemorrhage. Twenty-three of 97 in the control group and seven of 103 in the treatment group required surgery. There appeared to be a reduction in the transfusion rate after the first three days of hospitalization in the treatment group. There were no significant differences in mortality or in side-effects between the two groups.