Volume 4, No. 4 • Winter 1989

Safety Becomes Major ASA Meeting Topic In Exhibits

John H. Eichhorn, M.D.

Technical and scientific exhibits at the October ASA annual meet” in New Orleans featured many products and ideas intended to help promote safety in anesthesia practice.

Manufacturers of anesthesia machines, monitoring systems and automated anesthesia record devices all focused on operating room anesthesia data management system. Various companies now offer integrated systems that collect all the patient and machine monitor data into a central display and alarm panel.

These centralized, integrated systems were developed in response to the long-held belief that the data read-out and alarm messages from up to as many as eight or ten separate devices in various locations around the anesthesia work station can be confusing and distracting. With the new technology, monitoring information is displayed in one central area along with a unified alarm that identifies immediately for the user which device is sounding an alarm and what alarm threshold has been exceeded.

The intention is to provide a total package of the clearest possible information in the most easily accessible format to the clinician doing the case. The implication is that this will help optimize safe anesthesia care by both promoting vigilance and reducing delay in analysis of untoward developments. At this time, no emphasis was placed on the possibility of remote access to the same centralized information package by supervisors and/or teachers.

Instruments capable of monitoring the concentration of volatile anesthetics (usually inspired but some both inspired and expired) were prominently displayed by many manufacturers. Suggestions of potentially safer anesthetic practice through the use of these devices were made by many salespersons. However, inquiries regarding both the mechanism of this enhanced safety and related supporting arguments yielded very little information.

A “closed-system” simple auto-transfusion device for relatively small quantities of blood (two-three units) was displayed. The intention is that this would be used in moderate blood-loss cases for which it would not now be considered worthwhile to set up a U-scale blood retrieval, washing and reinfusion system. The goal is not only avoidance of bank blood but also repletion of volume with autologous blood in patients unlikely under usual circumstances to receive transfusions, potentially improving hemodynamics and recovery.

Once again, 31 companies offered pulse oximeters for sale. There were some new configurations and combinations, but few changes in the basic technology. There was one new instrument containing skin surface pulse oximetry and capnography. Another new capnograph, not yet available for purchase, measures C02 via acoustic wave changes at a surface coated with a special polymer that reversibly binds C02. This technology could support either mainstream or side stream measurements.

For measuring real-time continuous wave form noninvasive blood pressure, a new technology derives arterial pressure from an initial traditional calibration followed by measurements from sensors evaluating the arrival of the pulse wave at the finger and forehead. An apnea monitor intended for use, for example, with any of the many PCA pumps shown in the exhibits employs sensors under the mattress of a regular hospital bed evaluating the patients motion for the rhythmicity of normal breathing.

Among the scientific exhibits (NOTE: see related stories about Pierce Award winners Page 38 and about FDA sponsored material Page 47) there were several safety-related themes. Computer-driven simulator/trainers were again featured, revealing advances in these technologies since last year. Several presentations dealt with optimizing airway management. There was an exhibit on the early detection of air emboli. An exhibit from the Netherlands promoted performance of preanesthetic checklist procedures in a manner analogous to an airliner pilot and co-pilot in a cockpit preparing for take-off. A major exhibit realistically demonstrated electrical hazards and how to increase patient electrical safety in the OR. Finally, exhibits demonstrating a variety of anesthesia quality assurance systems were featured and attracted great interest.

Dr. Eichhorn, Harvard Medical School and Beth Isreal Hospital, Boston, is Editor of the APSF Newsletter.