Influence of Intravenously Administered Heparin on Clotting of Lymph in the Dog

¹ From the Department of Medicine, University of Colorado School of Medicine, Denver, Colorado

Heparin was given intravenously at rates of 2–3 u/kg/min. or by single injection in doses of 65–290 u/kg to anesthetized lymph fistula dogs. Prolongation of the thrombin and prothrombin time of plasma occurred almost immediately. This effect appeared in the lymph only with the larger doses and after a delay in time. This delay was not abolished by large single doses of heparin. The duration of effect in lymph was shorter than in plasma. These differences from plasma effects were more marked in cervical than in thoracic lymph. The phenomena were attributed to the time element of lymph formation and flow, to delay and screening of large molecules passing from plasma to lymph, and to inactivating and excretory processes.