The anesthesia machine

 The anesthesia machine

As anesthetic agents and techniques have evolved, so have the delivery systems. Modern anesthesia requires the ability to administer gases and vapors in the desired combinations, often while mechanically ventilating the patient’s lungs. Here we present step-by-step the concepts on which anesthesia machines are based. We are starting with systems that sport neither valves nor means to store gases, advance to systems that can store gases – which requires a couple of valves, and advance to systems in which the patient rebreathes his exhaled gas – but without carbon dioxide. Thus, we will have set the stage for the modern anesthesia machine. 

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