Regulation of Blood Flow in Gross-Circulation for Intracardiac Surgery.

Summary In acute experiments on dogs 2 types of flowmeters were compared for regulating the 2-way flow of blood in donor cross-circulation during intracardiac surgery. (1) By arranging 2 flow rate recorders (5734 bristle flowmeters) to act as a flow-difference-meter, differences in the volume flow of blood from donor to recipient and vice versa could be recorded. This method appears, however, rather complicated for use in the operating room. (2) A cumulative flow recording method was found to be simple and reliable. For this purpose, the donor rested on zero reading scales which acted as a cumulative flowmeter indicating blood inflow and outflow from the donor. With the aid of the scales, blood loss from the donor could be accurately measured and replaced by intravenous infusion. For practical purposes it is felt that continuous weighing of the donor provides the best method for insuring equal bidirectional flow in cross-circulation under operating room conditions.