Recent advances in heart-lung by-pass systems

The advance of heart surgery has been closely coupled to developments in external blood flow devices. The state of the art had reached au apparent plateau in the 1930´s when Dr. Laurence O´Shaughnessy, a renowned cardiovascular surgeon, reported that ¿¿ the real key to further advance in the surgical treatment of established cardiac defects will be provided by the provision of some simple and efficient method of maintaining cerebral (brain) circulation while the heart is temporarily out of commission.¿1 There has been a tremendous effort exerted in the past decade, and particularly in the past five years toward the solution of the problem as stated by Dr. O´Shaughnessy.2,3 However, substitute systems for temporarily replacing the heart and lung functions involve far more than a conventional fluid pump and a simple aerator. Details of a heart-lung bypass system co-operatively developed by the National Heart Institute and the Instrument Engineering and Development Branch of the National Institute of Health are described. The system has been used in over 250 operations.