General Anesthesia Machine: Description And Function

A form of general anesthesia machine has been around since 1917 when Henry E.G. Boyle (1875-1941), modified the Gwathmey-Woolsey Nitrous Oxide-Oxygen Apparatus invented by two anesthesiologist Dr. William C. Woolsey (1876-1919) and Dr. James T. Gwathmey (1862-1944) and introduced in the United States in 1912. This variation became known popularly as the Boyle anesthesia machine.

Present Anesthesia Machines

Over the decades, changes have altered the technology of the original machinery. It has become more complex. Computers and electronic devices now help calibrate, direct and control various aspects of the anesthesia machine. The evolution focused initially on improving the delivery system and continues to concentrate on improving the safety levels for everyone who comes in contact with the system.

However, the operational and functional basics remain the same. The anesthesia machine, still the most important instrument operated by an anesthesiologist, continues to perform four basic and necessary functions:

1. It provides the patients with O2 directly to a breathing system
2. It mixes the right volumes of anesthetic gases and vapors together with great precision. The very nature of the machine and the safety of its operation depends upon the interaction of the design of the machine – including the various safety features, and the skills and knowledge of the anesthesiologist
3. Facilitates patient ventilation
4. Minimizes any risks from using anesthesia for both patients and staff

A general anesthesia machine fills these roles in any of its varied types including the most common one – the continuous-flow anesthesia machine.

General Anesthesia Machine

For more than a century, the delivery of anesthesia to patients has improved. The general anesthesia machine, once rudimentary and very simple in design, has become more complex. However, through technological innovations, the design and the process have adopted the latest technology, improving safety without abandoning the essential functions at the heart of the pioneering work of Gwathmey and Boyle.