Most anesthesia deaths and injuries attributable to pre-existing equipment faults or to errors in equipment set-up could be avoided if the function of anesthesia apparatus is adequately checked before each case. Although these set-up errors and faults do not account for the largest portion of anesthesia untoward incidents, they are a source of patient risk which clearly can be addressed.
Manufacturers do provide checkout instructions in their operator’s manuals. Variations of suggested checkout procedures are available in the literature.
Yet, there is evidence that some anesthetists still do not fully conduct a proper pre-use check of their apparatus. Further, there may be anesthetists who are not convinced of the need to routinely conduct a complete check of the equipment before use.
Two years ago the FDA met with representatives of the anesthesia medical community and industry to discuss cooperative efforts to reduce patient risk during anesthesia. During that meeting the agency was asked to take the lead in developing and issuing a general guideline for users on how to perform a pre-use checkout on anesthesia equipment. The objectives of such FDA-sponsored guidance were to promote the concept of routine checkout and to provide basic techniques that anesthetists could adapt to their own specific equipment and clinical practices.
The general guideline, “Anesthesia Apparatus Checkout Recommendations;’ was developed by a small group of experts which included practicing anesthesiologists, biomedical engineers, and industry representatives. This initial draft was based on a checklist developed over ten years in the residency program at Massachusetts General Hospital. This was modified and honed substantially over an 18-month period. Elements of checklists from other recognized sources were incorporated. The resulting procedure was evaluated at several hospitals and by the three major manufacturers of anesthesia machines. It was then reviewed by FDA’s advisory panel on anesthesiology and respiratory therapy devices. A Notice of Availability of the draft checkout recommendations was published in the March 28, 1986 Federal Register to solicit public comment.
The final version of the checkout recommendations, which appears in this issue of the APSF Newsletter, provides a general checkout and inspection procedure designed to be performed daily and, in an abbreviated form, before each case by anesthesia professionals. It is designed to ensure that the anesthesia gas machine, patient breathing system, monitors, and other apparatus which together comprise the anesthesia delivery system are correctly interconnected, are properly adjusted, and function as expected. Although the checkout recommendation is being issued by the FE)A, it is not a federal regulation and clinicians are not legally obligated to use it. It is only intended to be used as a guideline which anesthetists should modify as needed to accommodate differences in equipment and variations in local clinical practice. Modifications are not only appropriate but they are encouraged. It is suggested that such changes be peer reviewed.
One example of an appropriate modification to the checkout recommendation which users may wish to make relates to the test for leaks in the machine and breathing system presented in step 16. This generic leak test, although appropriate for all machines, requires some care to perform correctly on machines which employ check valves upstream of the common gas manifold. If not performed precisely as dm3iW, a significant leak may go undetected. To avoid this problem, one manufacturer of such machines provides special test apparatus and a different method for accomplishing this leak test. This manufacturer would prefer that the users test the machine as described in the operator’s manual. This illustrates the need to carefully review the operator’s manual before using the checkout recommendations. The FDA recommendations do not relieve users of their responsibility to be aware of any special procedures or precautions described in the operator’s manual supplied with their equipment.
Early in the development process, it was resolved that the recommendations should be kept as brief and as simple as possible to be practical for daily clinical use hence the single page format. Yet, it needed to be generic and sufficiently comprehensive to detect most of the common setup errors and equipment defects. These competing objectives complicated the development and led to compromises. For example, one trade-off centered around a means to detect a grossly malfunctioning vaporizer. While the test considered was useful and desirable in principle, it was judged too complex and time consuming to justify including it given the rarity of such a gross malfunction. Some users may disagree with that decision and may wish to include such a test in their own daily routine. For information on one way to perform such a test, contact: ECRI (5200 Butler Pike, Plymouth Meeting, PA 19462).
The checkout procedure should be adequate explanation for most users, however, a more detailed description of most of the tests can be found in the companion publication to the educational videotape “Machine Check-Out” in the ASA Patient Safety Series. That checkout procedure is similar to the FDA recommendations. Copies may be obtained from the ASA. An additional source of detailed information on pre-use of anesthesia apparatus is Understanding Anesthesia Equipment, (2nd Ed.) by Dorsch and Dorsch (Williams & Wilkins, 1984).
The ASA, AANA, and industry plan to assist the FDA in disseminating these checkout recommendations. It is anticipated that copies will be made available by anesthesia equipment manufacturers and that the recommendations will be reprinted in ASA and AANA publications. A Notice of Availability is also scheduled to be published in the Federal Register informing the public of the availability of the final “Anesthesia Apparatus Checkout Recommendations.” Additional copies of the checkout recommendations may be obtained on request by writing to the Division of Technical Development (HFZ-240), Office of Training and Assistance, CDRHIFDA, 5600 Fishers Lane, Rockville, MD 20857.
Mr. Carstensen is Engineering Consultant, Center for Devices and Radiologic Health, U.S. Food and Drug Administration.