[In vitro studies on the effect of alpha-chymotrypsin on hemostasis]

Postoperative bleeding was observed in 2 patients for whom alpha-chymotrypsin had been prescribed to prevent haematoma or oedema formation. In vitro experiments with citrated blood added with alpha-chymotrypsin evidenced (thrombelastogram, hirudin tolerance test, euglobulin-lysis time) an action on haemostasis. As compared to blanks, the application of an alpha-chymotrypsin dose which was 100-fold higher than those currently used in therapy resulted in a significant shortening of the r-time (thrombelastogram), delayed blood clotting (hirudin tolerance test) and a shortening of the euglobulin-lysis time. In vivo experiments are needed for further elucidation.