Anatomy of an Outbreak: After the Fallout
By Kathy Dix
Outbreaks are a frightening occurrence in any healthcare setting, but offer an opportunity to improve processes and procedures in order to prevent future outbreaks. Infection Control Today explored the causes and effects behind a 2001 outbreak that spread pseudomonasto several patients at two different institutions.
In September 2001, Glenda Gaye Mayernick, RN, CIC, director of infection control at Skyline Medical Center in Nashville, notified the Tennessee Department of Health of an increase in the number of Pseudomonas aeruginosa and Serratia marcescens isolates associated with bronchoscopy, as reported in the New England Journal of Medicine in January 2003.
Mayernick and her colleagues had been following a possible outbreak at their facility since July 2001, when a bronchoscopy performed on a same-day care patient yielded a bronchial washings culture that grew P. aeruginosa. Two other patients undergoing bronchoscopies also had cultures that grew P. aeruginosa. Two pulmonologists who had performed the procedures spoke with the chairman of the infection control committee, feeling that the cultures were contaminated, as the patients did not appear to have clinical Pseudomonas pneumonia and none had a prior history of Pseudomonas.
The director of infection control and the director of surgical services both reviewed cleaning procedures and found no problems. However, patients continued to have positive Pseudomonas cultures after bronchoscopy. The staff took cultures of the most likely sources of contamination, but all potential sources appeared to be clean water from the washer, water from the scope cleaning sink, and from a bottle of saline used with the procedures.
Pseudomonas isolates were preserved for possible pulsed field gel electrophoresis comparison as more cultures tested positive for P. aeruginosa; additional cultures were obtained from the outlet from compressed air, traps in the washer/disinfector, lubricant used in the procedure, the alcohol, the enzymatic cleaner, the cleaners cup, the lidocaine used in the patients noses, and the high-level disinfectant. Still no source was revealed.
The state public health department was notified and was requested to help; an officer from the Epidemic Intelligence Service (EIS) of the Centers for Disease Control and Prevention (CDC) was dispatched while still more cultures were obtained, from epinephrine used for the scopes injection port, from sterile D5W, a needle used for injecting saline during the procedure, the suction button on the scope, the tips of the scopes, the scissors used to cut the tip off the D5W, the towel used in the bottom of the scope cabinet and the syringe used to inject saline during bronchoscopy. None showed any growth.
On Sept. 17, 2001, the EIS officer arrived to assist with the investigation. The EIS officer had heard of contamination of biopsy ports at another facility, so Jayesh A. Patel, MD, the hospitals infectious disease physician and chairman of the infection control committee, was able to twist the cap off a biopsy port on one of the two scopes in question. The cap, however, was designed to be permanent and not removable by hand.
Cultures taken from the inside of the cap and from the biopsy port of both implicated scopes revealed P. aeruginosa and S. marcescens. The scope manufacturer was notified and the scopes were removed from service on Sept. 18. Even after being run through the washer/disinfector three times with the cap removed from the biopsy port, some of the cultures still grew P. aeruginosa.
Loaner scopes from the manufacturer were received, cultured to ensure no contamination, and then put into use on Oct. 3. Two other scopes were received in mid- October; one of these was found to have a removable cap later that month. The manufacturer was notified and the scope was removed from use. The second scope later grew the same Pseudomonas strain and was removed from service. The Food and Drug Administration (FDA) received mandatory notification from the state EIS officer by phone, and Mayernick spoke with the local FDA officer and submitted the necessary paperwork. The manufacturer dispatched its director of microbiology to the hospital to review its cleaning and disinfection practices; they then instituted a nationwide recall of 15 models of bronchoscopes that had a design element involving a biopsy port cap that was designed to be non-removable.
The first thing we did was review our cleaning procedures, because thats what you always think about with bronchoscopy, Mayernick remembers. Scopes are hard to clean, and so you want to make sure you do everything you can to clean them appropriately. We went over our policies and procedures, didnt see anything wrong, and the director reviewed the cleaning procedure with the staff. We didnt find anything wrong with that.
As more positive cultures were found, the hospitals staff became more perplexed so many potential sources of P. aeruginosa had been tested, but the source remained elusive. We were ready to close our endoscopy lab, because we knew there was a problem, but we just had not found it, she adds. That led to her call to the state health department.
An urgent recall was sent to hospitals that had the pertinent models, but Mayernick says, the wording of the letter could have been better. At the time, they implied that it may have been due to our cleaning procedures, she says wryly. When the expert [from the manufacturer] came out, she didnt see anything that contributed to the outbreak.
Johns Hopkins Hospital in Maryland had provided an incorrect address; the proper department did not receive the recall letter in the first mailing. The hospital continued using the affected endoscopes, not knowing they were exposing patients to P. aeruginosa, and the outcome was two lives.
The main thing with scopes is pre-cleaning and making sure your machine is working properly, Mayernick stresses. The first thing you should always do is review your cleaning procedures. Change the filter periodically. The pre-cleaning is so important, because things can dry on there. Weve always been complimented on our pre-cleaning procedures when we send scopes out for cleaning.
After extensive investigation, it was found that a manufacturing change in 1997 had led to the change in the biopsy port housing. A removable cap was screwed on and fixed with adhesive to ensure that it was no longer removable. However, some not all of the affected models had insufficient adhesive to place the cap permanently on the port housing.
After discovering the source of the problem, the infection control team at Skyline researched how they might clean the scope with the cap removed. After three sessions through the entire cleaning process, pseudomonas still remained on some parts of the scope even with particular attention paid to those areas.
Mechanical cleaning of the hidden contaminated surfaces could not be accomplished with caps in place, Mayernick explains. Disinfection requires approved disinfectant for a specified period of time. The loose port caps may have created air pockets that prevented effective contact between the disinfectant and microorganisms. Also, drying is required to prevent microorganisms. The biopsy port caps might have prevented thorough drying of surfaces inside the caps.
The microorganisms origin remains elusive; it may have originated from a patient, from the scope-cleaning sink, or from any number of sources. Pseudomonas grows well in water, in sinks, in faucets and so forth; thats why you do the cleaning processes. Regardless of whether it came from a patient, the problem was that you couldnt adequately clean the scopes with caps in place, she adds. Mayernick emphasizes that all of the positive cultures were from two new bronchoscopes the hospital had received in July 2001. There was no contamination associated with our older non-video bronchoscopes, she clarifies.
William Schaffner, MD, professor and chair of the Vanderbilt University Medical Center department of preventive medicine, co-authored the New England Journal of Medicine article with Mayernick, David L. Kirschke, MD, and others. Youll recall that in many outbreaks, the outbreak is a consequence of something that occurs within an individual institution. This outbreak was detected and obviously occurred in an individual institution, but as a consequence of a manufacturing defect, he says. The hospital did what every book says you should do they called for help. They called the Tennessee Department of Health and they asked for assistance. Thats how I entered, because Im a consultant to that division.
After quick discussion, they sent out Kirschke, an EIS officer, to assist in the investigation. However, Schaffner recalls, We had great concerns about how the company and the FDA responded to this problem. I think it is fair to say that our concerns about these issues continue to this very moment.
He clarifies, I do not believe that the FDA which has had a lot of problems recently has the resources or personnel to change their approach materially since that time to this kind of issue. But the company initiated a worldwide recall of these devices and corrected them, and I believe them I would just like to see more documentation.
Schaffner questions the potential response if such an outbreak should occur again. If something similar happened tomorrow with another medical device, Im afraid that the energy for response remains substantially with the company in these kinds of circumstances. The FDA depends upon the company to respond. From my personal point of view, thats not a comforting notion. I think that the FDA ought to be empowered and funded to be much more assertive. They depended entirely on the company and we thought the company could have responded more openly and aggressively in the recall. I dont want to keep hitting this specific company over the head. As far as I know, they havent had any problems since. But if this were another company, the FDA would depend on the company to define the problem and solution and act on it, and they depend on the company to communicate with the users of the product. That puts a huge amount of responsibility on the company, he points out.
When it comes to medical devices, the FDA has a much less elaborate program than they do for drugs and vaccines, and that has always been the case. I think some of that is the law; some of that is FDA tradition, the way theyve chosen to operate; and some of it is that the FDA is underfunded in this area. Ive said from the beginning, if we have enhanced expectations of the FDA, as I do, I have to be willing to give them more resources, and I am.
Raise my taxes, give them the resources they certainly need a lot more resources. When it comes to pharmaceuticals, its clear that we as a society were not giving them enough resources. If we want a vigorous FDA, we have to fund it and give them appropriate legal authority, Schaffner concludes. Responding to an article that had been written in 2002 about this outbreak, the manufacturer wrote to clarify several errors that were included in the original story.
The article repeatedly refers to a design flaw or design error in certain Olympus bronchoscopes, wrote Laura Storms-Tyler, director of regulatory affairs and quality assurance for the Medical Systems Group at Olympus America Inc. The bronchoscopes were recalled because of a manufacturing non-conformance in the amount of adhesive-sealant and torque used to secure the biopsy port in place. Olympus determined that on some instruments, an inadequate amount of this adhesive-sealant and torque was applied during the manufacturing process, allowing this part to loosen. As soon as Skyline Medical Center (officials) discovered this loose port, and Olympus determined that there was a potential for the biopsy port to loosen on bronchoscopes at other sites as well, Olympus initiated a voluntary, nationwide recall of all affected models, she adds.
The part is not a valve, but a cover or housing that surrounds the biopsy port. There was no delay in informing FDA about either the unfolding events at Skyline, or the initiation of the recall mailing. The moment we learned of a single set of circumstances involving our bronchoscopes at one hospital, we began an immediate inquiry that led to a voluntary nationwide recall, Storms-Tyler elucidates. In accordance with the Medical Device Reporting regulations, Olympus informed FDA of the data it had available regarding the Skyline incident on Oct. 17, 2001. In mid-November, Olympus concluded that the potential for a loose biopsy port was not isolated to the bronchoscopes at Skyline Medical Center, and decided to initiate a nationwide recall. The investigation into the incident at Skyline Medical Center was not concluded until mid to late-November. Certified recall letters dated Nov. 30, 2001 were sent out on the following Tuesday, and the FDA was informed of this recall action.
In the initial recall letter, dated Nov. 30, 2001, we clearly stated If you detect any looseness in the biopsy channel port, please discontinue use of this bronchoscope, and return the bronchoscope to Olympus repair facility as noted below. Storms-Tyler continues. It did indicate that if no looseness is detected in the biopsy channel port, you may continue to utilize the bronchoscope. However, Olympus would like you to return the bronchoscope at your convenience so that we can upgrade the biopsy port housing. Although there was no indication at that time, and to date there still is no evidence, that instruments with tight biopsy ports pose any contamination risk, Olympus nevertheless instructed users to return these instruments to Olympus at their convenience. The second notice, dated Feb. 27, 2002, sent to those which had not responded to the first letter, reiterated that even if no looseness is detected in the biopsy channel port, you are still required to return the bronchoscope so that Olympus can upgrade the biopsy port housing. As of July 31, 2002, 97 percent of the units have been returned to Olympus America, modified and returned to the customers. We have had telephone contact with 100 percent of the purchases of record of the remaining units, and we are working aggressively to ensure the remaining units are returned and repaired.
1. Kirschke D, et al. Pseudomonas aeruginosa and Serratia marcescens Contamination Associated with a Manufacturing Defect in Bronchoscopes. N Engl J Med 2003;348:214-220
A Second Outbreak at Johns Hopkins
AN INACCURATE MAILING ADDRESS may have led to a second outbreak of Pseudomonas at Johns Hopkins Hospital, several months after the first one at Skyline Medical Center. Not all facilities using the affected models of bronchoscopes received the first notification of recall; the letter to Johns Hopkins, for example, was sent to a loading dock at the facility and took several weeks to be routed to the pulmonology department. The manufacturer maintains that they sent the letter to the address provided by the facility.
The hospital had noted a rate of pseudomonas that was much higher than normal and instituted an investigation to determine the cause; the staff was puzzled, just as at Skyline, no Pseudomonas was found in any of the cultures taken from the involved bronchoscopes, items used to clean them or the areas where the bronchoscopies were performed.
By early February 2002 the concerns about infection had been raised on Dec. 31, 2001 the staff had determined the source of infection, pulled the bronchoscopes out of service for intensive cleaning, and corrected the problem before resuming elective bronchoscopies after approximately two weeks. The source of the problem was the same as at Skyline a loose cap on a port of the bronchoscope. At the same time, in early February, the hospital became aware of the nationwide recall notice, immediately returned all but one of the bronchoscopes to the manufacturer and offered the remaining scope to the FDA for review.
The hospital then instituted a thorough review of patient records and determined that approximately 100 of 410 scoped patients had tested positive for exposure to pseudomonas, a two- to three-fold greater incidence than expected for this organism in the patient group.1
However, it was likely that some of these patients because of their high-risk background with cystic fibrosis, HIV/AIDS, lung transplants and cancer might have already carried the pseudomonas bacteria before entering the hospital for their bronchoscopies.
Infections related to the outbreak may have been a factor in the deaths from pneumonia of two patients who were already critically ill at the time of their bronchoscopies. However, there can be no definitive link made between the outbreak and the deaths due to the patients already compromised state of health.
A second paper published in the same issue of the New England Journal of Medicine as the Skyline article addressed the Johns Hopkins outbreak. The authors concluded their paper with a pointed commentary on the current recall procedures required by the FDA, saying, Instrument safety and surveillance methods for bronchoscopy must be improved, and better recall procedures are needed for medical devices.2
They noted in their paper that two of the recalled bronchoscopes had been put into service in mid-June 2001, and that all recalled bronchoscopes were removed from service on Feb. 6, 2002. Outbreaks such as this one have led patients and physicians to question the safety of bronchoscopy a concern that is receiving heightened attention with the increased focus on patient safety, they wrote. This outbreak emphasizes the challenges that new forms of technology present with respect to adequate reprocessing of instrument and the importance of appropriate instrument design to adequate disinfection, since a loose part may have been the cause of the contamination. It remains to be seen whether the use of instruments such as sheathed bronchoscopes will protect patients from infections due to contaminated instruments. In the meantime, perhaps new standards should be developed to test and review the design of instruments with respect to disinfection before these instruments are used in patients.
Finally, they said, Our findings arouse concern about the adequacy of nationwide recalls of medical devices. Currently, the Food and Drug Administration relies on manufacturers to take full responsibility for product recalls, including follow-up checks to assure that recalls are successful ... A federal mandate that recall notices be sent to all physicians who may use a device could have shortened the duration of the outbreak we studied, decreasing the number of patients at risk. Such a measure might help ensure that future recalls are handled expeditiously and thus optimize the safety of medical equipment.
2. Srinivasan A, et al. An Outbreak of Pseudomonas aeruginosa Infections Associated With Flexible Bronchoscopes. N Engl J Med 2003;348:221-227.