In 1955, surgical instructor Gilbert Campbell and surgical fellow Norman Crisp researched the possibility of using a biological blood oxygenator to maintain circulation during open heart surgery. The method utilized an excised lobe of a dog lung. A laboratory pump coaxed deoxygenated blood through plastic tubing to a dog lung that was ventilated with oxygen. Oxygen rich blood was then returned from the lung to the patient.
A dog lung, or biological oxygenator, was first used successfully on March 23, 1955 on a 13-year-old patient. The operation was the first successful repair of an acquired heart lesion, as the holes in the patient's heart developed as a result of a car accident - the patient was not born with the defects.
Biological oxygenation was used in 14 operations and was abandoned after the invention of a mechanical oxygenating device that further simplified the process of circulation bypass.