E. J. Moran Campbell, 1925–2004
Authors: Norman L. Jones
Journal: American Journal of Respiratory and Critical Care Medicine (2004)

Dr. Moran Campbell, Founding Chairman of Medicine at McMaster University, 1968–1975, died on April 12, 2004, after a long battle with colon cancer. He was an outstanding scientist, physician, and educator, achieving a worldwide reputation as the foremost clinical respiratory physiologist of his generation. He changed how respiratory medicine was taught and practiced. Moran was born in 1925, the son of a Yorkshire general practitioner. In 1950 he obtained his medical degree at the Middlesex Hospital Medical School in London, and shortly after began research in the Department of Physiology at the same institution. He used the new technique of electromyography, together with pressure and volume measurements to provide the first comprehensive description of the mechanical events during breathing and the neural mechanisms that control the respiratory muscles. His book The Respiratory Muscles and the Mechanics of Breathing (1958) remains the seminal work on these topics. In it Moran developed a diagram (universally known as the Campbell diagram) that remains the standard tool for partitioning work of breathing. After a year at the Johns Hopkins University with Dr. Richard Riley, the foremost researcher in pulmonary gas exchange, Moran returned to London in the late 1950s. He applied the new techniques for measurement of blood oxygen and carbon dioxide pressures to patients with respiratory failure. He documented their blood gas derangements and formulated a new approach to treatment. Central to this approach was the careful control of inspired oxygen concentration to avoid carbon dioxide retention. Both the measurement of carbon dioxide pressure and the administration of small but precise increases in oxygen concentration presented obstacles, but Moran developed novel techniques to overcome them. To achieve precise increases in inspired oxygen concentration, he developed a mask into which a jet of pure oxygen was delivered using a precisely machined nozzle; this led to a reduction in pressure surrounding the jet (the Venturi effect), which thereby drew in room air through holes in the neck of the mask, precisely diluting the oxygen to achieve a small increase in concentration. The “Ventimask” has remained the standard of care ever since, and the approach received worldwide acceptance, and doubtless profited the manufacturer to an incomparably greater extent than the inventor (the only remuneration he ever received from the manufacturer was a free briefcase). He summarized his new ideas when he delivered the Burns Amberson Lecture at the Annual Meeting of the American Thoracic Society in 1967. The principles enunciated in this published lecture (Am Rev Respir Dis 1967;96:626–639) remain the cornerstones of care in respiratory failure. During the late 1950s, Moran became intrigued by breathlessness. He began with a series of studies in which breathing was impeded in healthy subjects by elastic and resistive loads. With Dr. Jack Howell he developed a theory of length/tension inappropriateness, which was based on a complex understanding