Summary
The role of catecholamines in the activation of coagulation and fibrinolysis following
surgery remains controversial. In this study 5 dogs were infused with 1, 2, 3, 6,
9 and 12 μg kg–1 min–1 of adrenaline at twice weekly intervals and were then reexposed to 3 μg kg–1 min–1. Pulse rate and factor VIII increased after infusion of 1,2 and 3 μg kg–1 min–1 but thereafter there was a diminished response and no response on reexposure to 3
μg kg–1 min–1 although this was not significant in the case of pulse rate. Euglobulin lysis time
shortened after each infusion of adrenaline and showed no development of tolerance.
A control series of dogs infused with saline showed no similar changes.
Both groups of animals were then bled to a blood pressure of 60 mm Hg for 60 minutes.
Pulse rate and factor VIII did not change but euglobulin lysis time shortened in both
groups. The results suggest that the activation pathways for changes in factor VIII
and euglobulin lysis time induced by adrenaline are separate.