Total left ventricular bypass without thoracotomy was done for periods of 12 through 48 hours in 22 dogs to study tolerance and various changes, especially on blood proteins. Thirty-two percent of the dogs were long-term survivors. No animal that was perfused 48 hours was a long-term survivor.
Changes in blood protein concentrations were evident with slight change in plasma turbidity after 12 hours, but a substantial increase in viscosity was noted at 36-hour and 48-hour levels. Total protein and serum albumin concentrations showed mild reduction late in the perfusion.
Formed-element changes included substantial elevation in plasma hemoglobin level and leukocyte response with marked reduction in platelets. Blood pH and blood gas determinations showed little change throughout. Profound morphologic changes, believed to be embolic in origin, were noted in liver, kidneys, lungs, and myocardium.