Changes in the Activity of Antihemophilic a Factor (F. VIII) and in the Bleeding Time Associated with Muscular Exercise and Adrenalin Infusion

Abstract

Both short-term (minutes) and long-term (hours) strenuous muscular exercise in normal persons resulted in a particular increase in the antihemophilic A factor (AHA = f. VIII) and in a shortening of the bleeding time. Similar changes were observed after intravenous adrenalin infusions.

Repeated short-term exercise tests in a normal person revealed a slight tendency to increase in all clotting factors, corresponding to a loss of water from the blood during the exertion.

The effect of adrenalin infusions on the AHA level seemed to be lower if a series of strenuous exercise tests had been undertaken during the preceding days.

Adrenalin infusions in patients with the moderate type (I) of von Willebrand's disease gave no marked decrease in the bleeding time, but a proportional increase in AHA activity as in normals. No definite effect of short-term exercise test on AHA or on the bleeding time could be observed in patients with the severe type (II) of von Willebrand's disease.

Adrenalin infusions in patients with classical hemophilia and severe AHA deficiency shortened their bleeding time, but did not induce measurable AHA activity.

Transfusion with exercise-activated plasma to a von Willebrand patient, type I, corrected the bleeding time, whereas no such effect was observed after transfusion with exercise-activated plasma dialyzed against saline. A correcting effect was also found after transfusions with exercise-activated serum; when dialyzing the serum against saline, no correction of the bleeding time could be observed.

No effect of short-term muscular exercise, or of transfusion with exercise-activated plasma, was observed on the prolonged bleeding time in a patient with thrombasthenia.