Numerous questions to the Committee on Technology are individually and quickly answered each quarter by knowledgeable committee members. Many of those responses would be of value to the general readership, but are not suitable for the Dear SIRS column. Therefore, we have created this simple column to address the needs of our readership.

Dear Q&A,

I am a private practice physician at a community hospital where the administration purchases and maintains our fleet of anesthesia machines. Several years ago they committed to replace all of our machines. Our understanding was that a single model of machine would be placed throughout the facility. Currently we have a blend of manufacturers and models, some of which will not be supported after next year. We are asking to expedite the purchase process at this time and make the fleet consistent within this facility. I have been asked to provide information justifying this move. Specifically, I was asked it there is an ASA standard (or equivalent) addressing the benefits of a single machine model within a facility. Or, asked another way, what are the drawbacks of having multiple types of anesthesia machines within a single group of users? Does such information exist or can you point me to any resources?

Michael G. Royce, MD Tulsa, OK

Dear Dr. Royce,

Thank you very much for your question to the Q&A column. We are unaware of any ASA standards or other recommendations regarding your situation, and, a similar question pertaining to an academic installation is also pertinent. Please allow us to categorize our responses to you.

Confusion. The range of currently available anesthesia delivery systems includes many different models and manufacturers, including machines for office-based practice, MRI, and Day Surgery centers. Having multiple models and manufacturers in a single operating room suite relies on the fact that each provider has been trained on, and maintains intimate familiarity with, a much larger spread of features, shortcomings, and quirks, than if a single anesthesia delivery system were deployed. Attention may be misdirected to the operation of the anesthesia machine and could have negative consequences for the patient.

Education. This immediately brings to mind the Dear SIRS article in the Winter 2004
Newsletter. Who will be the key individual or local “champion” for this endeavor, and does he or she meet the attributes outlined in the article? Will this individual have the time, desire, patience, and diligence to provide training on each machine for new anesthesiologists, nurse anesthetists, anesthesiologist assistants,anesthesia technicians and technologists, and biomedical equipment technicians? How will those responsible for training receive expensive manufacturer training on so many machines? The learning curve for competency on multiple machines will be far greater than the learning curve for one machine. Training alone sounds like a near full-time job for someone even with a modest turnover of anesthesia providers. For academic institutions, an in-depth approach to training residents cannot be met if the goal is to expose all residents to such a wide range of machines. How does one handle the first 6 months of anesthesia training, when students are facing a different machine each day while trying to learn so many aspects of anesthesia care?

Interchangeability. The multi-model/manufacturer selection is even less compelling given that every manufacturer and model available offers a unique range of solutions for the clinical problems that providers face. Objectively viewed, while there may be significant differences in operation and use, there probably are not sufficient differences in performance or features to have some of each available. Other issues, such as complexity of managing service arrangements, interchangeability of vaporizers and other components, familiarity of technical personnel with simple troubleshooting routines, etc., suggest that there are serious problems with this approach.

Safety. The safety issue is serious, since the “new provider danger period” is significantly extended, and affected not only by time-on-machine, but now by incidence of exposure to EACH machine. Providers who work intermittently (part-time or PRN), are going to be in the position of working with equipment with which they are only marginally familiar. New systems will incorporate more sophisticated modes of ventilation and monitoring, requiring the operator to be proficient on multiple machines that they may work with infrequently. Proficiency must include topics ranging from basic operation and understanding to the design features and troubleshooting. Proliferating anesthesia machines from multiple vendors, and perhaps multiple models from the same vendor, could potentially become a breeding ground for human error, especially in stressful situations. And, if this is a teaching OR, the safety issue is even more serious, since residents and students are trying to learn many diverse aspects of anesthesia care and should not have their attention diverted from patient care to learn the setup, machine checkout, nuances of operation, and troubleshooting of many different machines.

Technical Support. Issues related to the ownership and support of multiple anesthesia machines from numerous vendors would present significant challenges to any hospital. The issues include training of technologists and support staff with documentation of competency, spare machines, spare parts, a variety of disposables, as well as introducing interface complexities to patient monitors and record-keeping systems, and monitoring and maintaining multiple service contracts.

Economics. There are economic reasons to use only one type of machine, such as volume purchase discount, smaller stock of disposables, and lower training costs. For example, oxygen fuel cells and CO₂ absorbent cartridges may not be universally compatible and would need to be stocked for each of the machine types. Recordkeeping would also vary from machine to machine and could cause patient record problems. If a patient problem results, the cost to deal with the problem would most likely be at least the cost differential of buying one brand of machine over another.

Compromise. If there are multiple machines in a large institution, perhaps the best approach would be to populate different surgical sites with different types of machines. For example, the main operating room suite could have a single type of machine; the outpatient surgery center could have another type of machine, and the pediatric hospital yet another type. For the providers who live in each one of these single environments, there would be no issue with using a different machine each day. This might fit best for academic training programs that typically follow monthly rotations. The anesthesia providers at each site would only have to learn a single machine, thereby increasing patient safety and greatly reducing the learning curve for attaining proficiency.

Summary. Multiple models and manufacturers of anesthesia machines represent a number of potential hazards with additional liability, and will ultimately cost the hospital a great deal more money to support. Is it appropriate to make that milieu even more complex to new providers by adding the difficulties of learning how to operate and effectively use multiple potentially very different anesthesia machines?

Additionally, new microprocessor-based anesthesia machines come with the potential for undiscovered catastrophic failure modes. With multiple new machines the likelihood of discovering some of these modes at an inopportune moment in a given suite of operating rooms will increase. Our consensus is that the concept of placing multiple different anesthesia machines in a single suite of operating rooms is seriously flawed.

The information provided is for safety-related educational purposes only, and does not constitute medical or legal advice. Individual or group responses are only commentary, provided for purposes of education or discussion, and are neither statements of advice nor the opinions of APSF. It is not the intention of APSF to provide specific medical or legal advice or to endorse any specific views or recommendations in response to the inquiries posted. In no event shall APSF be responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with the reliance on any such information.