Hemodynamic effects of slow and rapid defibrination with defibrizyme, the thrombin-like enzyme from venom of the timber rattlesnake.
The hemodynamic response to slow and rapid defibrination was sutdied in anesthetized beagle dogs, with the following results: 1. Slow defibrination was a benign procedure that had little or no effect on the hemodynamic variables studied. 2. Rapid defibrination induced statistically significant decreases in cardiac output, stroke volume, and mean aortic arterial pressure. 3. Bradycardia, a drop in mean left v"ntricular pressure, cardiac and minute work indices, an increase in pulmonary artery pressure, and a drastic rise in pulmonary and systemic vascular resistances were also observed. Although physiologically apparent, these changes were not statistically significantly different from control levels. 4. Pulmonary capillary wedge pressure, left ventricular end-disatolic pressure, arterial pH, and blood gases were not altered by rapid defibrination. 5. In view of the similarities between the hemodynamic changes observed after rapid defibrination and acute myocardial ischemia, the role of decreasing fibrinogen concentrations and blood viscosity in aucte myocardial infarction and the sudden death syndrome is questioned.
D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D002302:Cardiac Output / Q000187:drug effects; D002496:Central Venous Pressure / Q000187:drug effects; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D010450:Endopeptidases / Q000494:pharmacology*; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration; D008297:Male; D010100:Oxygen / Q000097:blood; D011517:Prothrombin Time; D011652:Pulmonary Circulation / Q000187:drug effects; D012911:Snakes
D002245:Carbon Dioxide; D005340:Fibrinogen; D010450:Endopeptidases; D010100:Oxygen