CAUSES OF INCREASING PERICARDIAL PRESSURE IN EXPERIMENTAL CARDIAC-TAMPONADE INDUCED BY VENTRICULAR PERFORATION

It has been shown that the intravenous infusion of saline solution in a dog with stabilized cardiac tamponade produced an increase in perica rdial pressure. To demonstrate that this pressure increase is the resu lt of bleeding into the pericardial sac, an experimental study was con ducted, consisting of the injection of red cells marked with Cr-51 dur ing the intravenous infusion of saline solution in dogs with and witho ut progressive tamponade. The results showed that in the dogs without progressive tamponade, both the pericardial pressure and the red cell count in the pericardial cavity remained stable during the infusion of saline solution, whereas in dogs with progressive tamponade, the numb ers of marked cells and the pericardial pressure increased significant ly, following a similar pattern.