Anesthesia Machines

The modern anesthesia machine is a complex operating room instrument that incorporates a ventilator to optimize the delivery of inhaled anesthetics. The anesthesia machine has gradually evolved from simply a means to anesthetize and oxygenate a patient to an anesthesia workstation incorporating increasingly complex ventilator modes, end-tidal CO2 monitors, end-tidal anesthetic concentrations, minimal alveolar concentration estimators, and a means of monitoring vital signs.[1] Despite all these innovations and new instruments added to the anesthesia machine, an understanding of the anesthesia machine is still a core component of the practice of anesthesiology. Different types of anesthesia circuits exist. The most commonly used system in the modern-day anesthesia machine is the circle system, but other examples of anesthesia circuits include the Mapleson A, B, C, D (and Bain modification), E, and F (Jackson-Rees) systems. There is a T piece close to the patient for Mapleson D, E, and F systems.