Correspondence, C. Walton Lillehei to the Medical Director of the Dow Corning Corporation regarding the use of Antifoam A substance in the bubble oxygenator
Antifoam A, a substance made by the Dow Corning Corporation, was used in the operation of the DeWall Bubble Oxygenator. The substance, when coated along the walls of the debubbling chamber of the oxygenator unit, helped to dissipate bubbles introduced into the chamber to oxygenate blood.Description of the DeWall Bubble Oxygenator: Using a Sigmamotor pump, blood was transported via plastic tubing through the oxygenator unit which consisted of a vertical mixing chamber, a debubbling chamber, and a helix coil. Venous blood taken from a patient's major artery was pumped through the tubing and into the mixing chamber where oxygen was introduced into the blood by the addition of bubbles. The bubbles rose to the top of the chamber and spilled over into a debubbling chamber where any remaining bubbles were dispersed before the freshly oxygenated blood was returned to the patient.