ABSTRACT
For general anaesthesia to progress in the 20th century, it was necessary to develop an apparatus that could add ether or chloroform to a mixture of oxygen and nitrous oxide so that the concentration of volatile agent could be more accurately controlled. Second, it was necessary to devise a way in which an airtight connection could be made with the lungs so that the patient could receive the gas mixture undiluted with room air. Third, anaesthetist had to learn how to maintain ventilation of the lungs when the patient’s respiration became inadequate. And fourth, the anaesthetist had to devise a method of preventing collapse of the lungs when the surgeon wished to operate within the chest. It was the development of tracheal tubes in the 1920s that provided control of the airway, facilitated assisted and controlled ventilation, and opened the door for thoracic surgery, while control of ventilation was also facilitated by the development of carbon dioxide absorption breathing systems.
