►To reduce costs

Gas Man calculates and displays the cost of anesthesia administration, facilitating the comparison of agents and techniques. The user can practice and analyze low flow and closed circuit anesthesia to master techniques that minimize drug waste. Another clinical goal might be to achieve rapid, controlled, alteration of anesthetic depth at various times during the course of anesthesia while minimizing the cost to do so.

►To interpret monitors

Anesthetic agent monitors are common in clinical anesthesia practice. First-time users and even experienced users of agent monitors are often perplexed or disturbed by the difference between what is set on the vaporizer and the observed inspired and expired (end-tidal) measurements displayed and recorded. Occasionally either the vaporizer or the monitor may not be functioning properly. But, usually, both are correct. In such situations, the observed differences can be explained by the physics and physiology of the machine, drug, and patient. Gas Man, by simulating that physics and physiology, can be used to produce a good approximation of what is observed on the monitor, thus helping the clinician, technician, or engineer formulate a more accurate explanation for what was observed. In this manner, a Clinical Engineer can use Gas Man to explain how the vaporizer and monitors can be correct, even though the clinician might not yet understand the interactions that led to his or her confusion over the data.

Other Users of Gas Man

Gas Man can be used by many professions:

• medical personnel (e.g., students, residents, SRNAs, CRNAs, practicing physicians) in any of the ways described above;

• hospital Clinical Engineers, Biomedical Equipment Technicians and pharmacists;

• hospital and managed care administrators;

• manufacturers and marketers of agent monitors;

• manufacturers and marketers of anesthesia delivery systems;

• manufacturers and marketers of inhalation anesthetic drugs; and

• educators in other fields interested in creating simulation software for training and communication.

Clinical Engineers and Biomedical Equipment Technicians in hospitals can use Gas Man to better understand the technical and clinical complexities inherent in their equipment, and the interactions of drug, delivery system, and patient.

Pharmacists can better understand drug delivery system-patient interactions and the impact of drug choice and anesthetic duration on pharmacy costs and on the value provided to the institution.

Hospital and Managed Care Administrators can also learn to appreciate the trade-offs clinicians make between drug choice, quantity and cost of drug used, clinical care provided for the patient, and value of the anesthetic outcome – that is, time to return to normal function.

Manufacturers of agent monitors – particularly their marketing, sales and user education staffs – can better appreciate the questions that will be asked and the confusion that will initially be engendered when their products are introduced in the operating room. By preparing answers to these questions in advance, the introduction and continued use of the monitor will be facilitated.

Manufacturers of gas delivery systems (anesthesia gas machines) can use Gas Man to understand and explain why the concentration the patient inspires from the breathing circuit is not what the clinician set on the vaporizer, even when the vaporizer is performing perfectly. Understanding the clinical goals and administrative objectives taught by Gas Man should assist in designing new anesthesia machines.

Manufacturers of the anesthetic agents can better understand and explain the pharmacokinetics of the drugs they market, sell, or manufacture. Drug manufacturers can enhance patient care by helping clinicians learn to use the drugs effectively, unencumbered by limitations inherent in machine and patient that were previously difficult to overcome. Also, vaporizer specifications can be better determined by carefully considering breathing circuit kinetics and solubility of the drug in blood and other tissues. In addition, the implications of drug attributes such as solubility in blood and various tissues can be understood through Gas Man's computer modeling and simulation.

Veterinarians can use Gas Man to compare drugs and delivery systems applied to animals of various sizes. Gas Man allows adjustments of patient size from 50 g to 1500 kg – from mice to

very large animals. Similarly, pediatric human anesthesiologists can explore the difference between kinetics of large and small patients.

Educators in other fields might also be interested in Gas Man, since it demonstrates how the simulation of a complex process, combined with straightforward user interaction with the model, can effectively improve the user's understanding of the care environment and enhance performance on the job.