A disposable heart-lung machine. Results of animal testing

A small wave propagation pump (WPP) was incorporated into oxygenators to create a disposable heart-lung machine. The WPP provides undirectional micropulsatile laminar flow of 8 L/min against 800 mmHg. The smaller WPP can generate 4 L/min against 400 mmHg (cardioplegia), or reversed, and can create up to 150 mmHg negative pressure for suction. Power needs were 110 volts and 0.5 amps or 24 volts DC and 1.5 amps. The WPP is self priming (20 cc) and de-aired in less than 3 min. Seven dogs (average weight, 36 kg) were supported for 3 hrs. Flows could accurately be adjusted from 0.005 to 8 L/min. Flow through the oxygenator and perfusion circuit averaged 3.1 L/min (2.0 to 4 L/min). Serial analysis of blood samples showed minimal hemolysis and no significant change in hematocrit, hemoglobin, white blood count, red blood count, or platelet count (p > 0.01). The inexpensive WPP oxygenator combination function as a disposable heart-lung machine.