The Journal of Thoracic and Cardiovascular Surgery, Vol 97, 275-281, Copyright © 1989 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Anticoagulation by ancrod for carbon dioxide removal by extracorporeal membrane lung in the dog
ME Sinclair, G Reber, A Schweizer, KL Dorrington, P De Moerloose, CA Bouvier and JP Gardaz
Department of Surgery, Geneva University Hospital, Switzerland.
Ten dogs were subjected to defibrinogenation with an intravenous perfusion
of ancrod (1 unit/kg) (Arvin, Knoll AG, Ludwigshafen, Federal Republic of
Germany) over a 2 1/2 hour period. Six of them were subjected to
extracorporeal elimination of carbon dioxide with a polypropylene membrane
lung by means of veno-venous bypass. The remaining four dogs did not
undergo extracorporeal circulation and served as control subjects. In both
groups, ancrod administration itself resulted in a marked drop in alpha
2-antiplasmin (33% and 67%, respectively, of the baseline values) and in
slight but significant decreases in factor II and plasminogen activities of
25% and 20%, respectively (p less than 0.05), in the group subjected to
carbon dioxide removal. There were no significant changes in platelet
number or factor V and antithrombin III activities. During the 6-hour
bypass period, platelet count and antithrombin III and factor II and V
levels decreased significantly. No bleeding was observed. Histologic
examination of lung biopsy tissue showed no pathologic features. Analysis
of the membrane of the artificial lungs revealed no fibrin deposits. In the
control group, except for a drop in alpha 2- antiplasmin levels (54%), no
significant changes in hemostatic parameters occurred during the
corresponding 6 hours. We conclude that, despite the drop in coagulation
factors and in alpha 2-antiplasmin activity during bypass, ancrod can be
considered as a valuable alternative anticoagulant for extracorporeal
carbon dioxide removal.
