Andreas Vesalius’ understanding of pulmonary ventilation

• Over 450 years ago, Vesalius grasped most of the mechanical essentials of tidal and forced respiration.
• He already recognized that atmospheric pressure carried air into the lungs as the chest expanded.
• He described an in vivo experiment of breathing, some 120 years before John Mayow produced his artificial model.
• He was likely the first to report on the technique and life-saving function of positive pressure ventilation through a tracheotomy.

The historical evolution of understanding of the mechanical aspects of respiration is not well recorded. That the anatomist Andreas Vesalius (1515–1564) first recorded many of these mechanics in De Humani Corporis Fabrica Libri Septem has received little attention. We searched a digital copy of De Fabrica (1543) and its English translation as provided by Richardson and Carman (1998–2009) for references to aspects of pulmonary ventilation. We found that Vesalius grasped the essentials of tidal and forced respiration. He recognized that atmospheric pressure carried air into the lungs, approximately 100 years before Borelli did. He described an in vivo experiment of breathing, some 120 years before John Mayow produced his artificial model. He reported on positive pressure ventilation through a tracheotomy and on its life-saving effect, some 100 years before Robert Hook did. In publicly recording his insights over 450 years ago, Vesalius laid a firm basis for our understanding of the physiology of respiration and the management of its disorders.