Asepsis in Anesthesia Often Under-Appreciated

William M. Slater, M.D.

To the Editor

Several years ago anesthesia residents used the old red rubber endotracheal tubes. After use, we used a bottle brush to scrub them in the sink. I was not taught to avoid handling the lower part of the tube, and I was cavalier about where I laid the uncovered tube. Being new to medicine and naive, I thought of the operating room as a clean, sterile, environment. Now we are taught to avoid contamination of the unpackaged endotracheal tube, keeping it sterile until it resides in the patient’s own local flora. I was originally taught to intubate using a method of opening the mouth wide with my right long finger and thumb on the patient’s molars. Many residents are now being taught to intubate without putting their fingers in the patient’s mouth at all. By carefully inserting the blade in the patient’s mouth and lifting gently, advancing in increments, the intubation can be accomplished in most patients with only the blade and tube entering the mouth. Most of us wear gloves when intubating, to protect ourselves as well as the patient. Things change.

Why all the fuss? Why be concerned with putting a laryngoscope blade that has been soaked in Cidex, gassed or autoclaved, into a patient’s mouth? The problem lies in what happens to the blade from the time it is disinfected to its insertion in the patient’s mouth. It is rare that it is protected from the contaminated environment. The disinfected blades are frequently delivered to a potentially contaminated surface. In preparing for our case, we have often contacted contaminated surfaces prior to assembling the blade and its handle. But we use silverware that is often in contact with a table in a public restaurant, don’t we? Next time you are in a restaurant, watching an employee clean an adjacent table, wiping the table top, then wiping the seats, then going to the next table top, think about it. Well, the incidence of cross contamination must be very small, since I only get diarrhea once every few years. If I had the opportunity, I would use squeaky-clean silverware.

Microorganisms are real. What if you were eating in the operating room? Big time organisms there. Hepatitis virus remains virulent in dry secretions for two or three days. Nosocomial pneumonia organisms, antibiotic resistant hospital strains, the same strains that are the killers in the ICU, have been cultured off of the knobs of the flowmeters of the anesthetic machine. Herpes viruses may be present. Tuberculosis is back and some strains are highly resistant. AIDS virus, a pansy of a virus outside the body, and probably not a threat, but it has given us more and more patients who are immunodepressed. There are also patients who are immunodepressed because of chemotherapy, graft-host rejection prophylaxis, and other reasons. Those patients should be protected from possible contamination resulting from our care.

When you place your hands in a patient’s mouth to intubate, to extubate, in airway insertion and removal, in placing and removing esophageal stethoscopes, nasogastric tubes, in auctioning the pharynx, it is difficult, if not impossible, not to spread secretions. The anesthesia circuit has to be handled, the flowmeter knobs, I.V. poles, etc. have to be adjusted, or positioned. As the anesthetic progresses, there is the possibility for further spread of the organisms. Many (most?) of us wear gloves. Our anesthesia working space is contaminated. The gloves are a barrier between ourselves and the contaminants, but rarely do they protect the patient.

However, I still see anesthetists not wearing gloves to intubate, laying unpackaged endotracheal tubes on the patients chest prior to intubation, and wedging a tonsilar sucker between the pad and the table between repeated pharyngeal suctions (how often is that space well cleaned!)

Nosocomial Danger

In spite of the potential, there is apparently a low incidence of cross contamination. Most likely we would not be aware of causing a nosocomial infection. We probably would not learn of some infections because the symptoms may not appear for months. Other infections may be attributed to other parts of the hospital. If the apparent incidence is low, which it probably is, there should still be concern, for the numbers are large. There are approximately 18,000,000 endotracheal anesthetics given yearly in this country alone. The American Society of Anesthesiologists, the Joint Commission of American Hospitals, and others, recommend that all instruments that come in contact with mucous membranes undergo a ‘high level of disinfection.” For the last few years, I have been working as a locum tenens anesthesiologist in eight different states. I know first hand that there are many anesthetists who still hand wash their blades at the sink. Many more comply with the standard recommendations. In either case, unless the blades are kept clean or sterile right up to the insertion into the patient’s mouth, the possibility of introducing pathogens into the patient is a real risk. With so little effort, with such a small change in technique and habits, this risk can be avoided. Disinfected blades can be packaged in a manner that allow their placement on the handle while still in the package with a .no touch’ technique, the cover removed only immediately prior to insertion in the mouth, and then the blade immediately placed back into the same package for pick up and cleaning.

Alternatively, a sterile barrier film sheath, recently made available, can be applied in a same “no touch” technique, the outer cover removed immediately prior to insertion into the patient’s mouth, and immediately after intubation, the contaminated sleeve can be disposed of, allowing the connected blade-handle to be placed on any work surface, ready for another sleeve application. This latter device is kinder to bulbs and blades, and they have a longer life before repairs or replacement are necessary. With a little practice, an esophageal stethoscope can be fed into the mouth or nose in a .no touch” technique straight from its package. With a little practice, other similar ‘no touch’ techniques can be used for temperature probes, nasogastric tubes, etc.

Things change. Cloves are becoming a way of life in anesthesia practice. We are more conscious of the implications of needle sticks. We have become more aware of possibilities of our techniques contributing to a patient’s becoming infected. We are increasingly under the scrutiny of others in the O.R. who have been more involved in aseptic practices. For the most part, treatment of our laryngoscope blades has been mandated by outside influences. Their intentions, however, have fallen short. The important factor is to keep the blade aseptic right up to its insertion. It is difficult or perhaps impossible to prevent contamination of our work area, but by awareness, and new techniques, we can avoid contaminating endotracheal tubes, laryngoscope blades, esophageal stethoscopes, etc. The change required to do this is minuscule, and takes no further time. It is good and right so to do.

William M. Slater, M.D. Las Cruces, NM