In the Aftermath of an Outbreak, Processes, Device Design Come Under Scrutiny

By Kelly M. Pyrek

In the May 2012 print issue of ICT, we explore the dialogue in the sterile processing community that was sparked by a report in the mainstream media on dirty surgical instruments. In actuality, the genesis of The TODAY Show segment and a report from the Center for Public Integrity is rooted in a study in the December 2011 issue of the journal Infection Control and Hospital Epidemiology by Pritish Tosh, MD, of the Mayo Clinic Division of Infectious Diseases, and colleagues, who reported on organ/space surgical site infections (SSIs) that occurred after arthroscopic procedures and were due to Pseudomonas aeruginosa of indistinguishable pulsed-field gel electrophoresis (PFGE) patterns occurring at a Texas hospital from April through May 2009.

Tosh, et al. (2011) report that cultures of environmental and surgical equipment samples were performed (samples included those taken from sink drains in the ORs and instrument reprocessing areas, samples of water sources in the ORs and in instrument reprocessing areas, and samples from equipment, such as the suction channels of shaver handpieces), and selected isolates were analyzed by PFGE. Surgical instrument reprocessing practices were reviewed, and surgical instrument lumens were inspected with a borescope (a 3-mm clinical endoscope) after reprocessing to assess cleanliness. The investigators report that their case-control study did not identify any significant patient-related or operator-related risk factors. P. aeruginosa grew from 62 of 388 environmental samples. An isolate from the gross decontamination sink had a PFGE pattern that was indistinguishable from that of the case patient isolates. All surgical instrument cultures showed no growth; however, the investigators say that endoscopic evaluation of reprocessed arthroscopic equipment revealed retained tissue in the lumen of both the inflow/outflow cannulae and arthroscopic shaver handpiece. No additional cases occurred after changes in instrument reprocessing protocols were implemented. After this outbreak, the Food and Drug Administration (FDA) released a safety alert about the concern regarding retained tissue within arthroscopic shavers.

Tosh and colleagues concluded  that these SSIs were likely related to surgical instrument contamination with P. aeruginosa during instrument reprocessing and that retained tissue in inflow/outflow cannulae and shaver handpieces could have allowed bacteria to survive sterilization procedures. The investigators emphasize that they observed the hospital's surgical procedures in their entirety, including infection-prevention processes such as preoperative cleaning of the operating room (OR) following the previous procedure; preparation of the patient in the OR for the surgical procedure; preparation of instruments in the OR for the surgical procedure; and the surgical procedure itself. To completely rule out a surgery-related problem, the investigators arranged for a simulation of knee arthroscopy using a cadaveric leg, to allow for closer inspection and manipulation of the surgical process without risking patient safety.

They also observed the facility's instrument reprocessing practices from the time that the instruments left the OR, through each reprocessing step, to packaging and storage for reuse. Autoclave and reprocessing logs from the main reprocessing areas and from each surgical pod (for flash autoclaving) were reviewed. The investigators also interviewed surgeons, circulators, scrub technicians, instrument reprocessing personnel, infection preventionists, microbiologists and administrators. Two flash autoclaves were located in the surgical pod where the majority of the case procedures were performed, and were used up to six times daily during the outbreak period. The investigators report that two of the case patients and four of the control patients had instruments that required flash autoclaving during their procedures. They found that logs of the flash autoclaves were not always complete with regard to the patient name, OR number and instrument name. Interviews of OR and instrument-reprocessing personnel revealed that the flash autoclaves had been used on rare occasions for routine sterilization.

Low-temperature sterilization with hydrogen peroxide gas plasma was used for reprocessing of the arthroscope, the arthroscope light cord, and the arthroscope camera/power cord in accordance with manufacturer instructions for the recommended duration. The sterilizer logs from revealed deficiencies in the documentation of biologic and chemical indicators that were performed on each load. After sterilization, packaged instrument sets were stored in a designated room adjacent to the instrument-reprocessing area. Before and during the outbreak period, it was common practice to place instruments on a rack within the OR pod on the evening before the procedures.

The investigators say that the reprocessing procedures used on the shaver handpiece were consistent with the manufacturers instructions, including brushing of the suction tube channel with a disposable bristled brush, immersion of the handpiece in enzymatic solution for more than one  minute (per enzymatic solution manufacturer recommendation), and autoclave sterilization. However, endoscopic examination of the shaver handpiece suction channel after reprocessing revealed remnant tissue and brush bristles that were not visible on routine visual inspection in each of the evaluated handpieces. Endoscopic examination of shaver handpieces from a different manufacturer that were obtained from another hospital within the health system also revealed remnant bioburden. Of note, reflux of irrigant solution through the shaver handpiece during surgery at times of suction tube compromise as a result of kinking of the tube or external compression was noted by surgeons at hospital X and documented during a simulated arthroscopic procedure that was performed using a cadaveric knee. More easily compressible suction tubing had been substituted into the arthroscopy kit, without notice to the facility, before the spring of 2009 by the medical supply company.

The arthroscope-cleaning procedure involved wiping down the instrument following a brief submersion of the instrument in enzymatic solution before high-level disinfection. The manufacturer-recommended procedure for arthroscope reprocessing included gross decontamination with submersion in enzymatic solution for 10 to 15 minutes before low-temperature sterilization. The distal ends of the shaver handpiece and the camera/power cord were wiped down with enzymatic solution. The manufacturer-recommended reprocessing instructions for gross decontamination included capping the distal end (with the electrical contact points) and submerging the entire device in enzymatic solution for 10 to 15 minutes.

Lessons Learned
Louise-Marie Dembry, MD, MS, MBA, a board member of the Society for Healthcare Epidemiology of America (SHEA) and Yale-New Haven Hospital epidemiologist, says that the Texas cluster of SSIs is a wake-up call for continued diligence in the sterile processing department as well as all areas of the hospital related to infection prevention.

 
"It's a reminder of how complex our medical instruments and devices are, how difficult they are to clean, and also how important the cleaning step is," Dembry says. "It's another call to vigilance when cleaning, disinfecting and sterilizing these devices. A member of the general public   who hears about outbreaks related to dirty surgical instruments may say, 'How hard is it to clean these items?' but they don't always understand the challenges of making sure it's done right. In this study, when they visually  inspected the instruments, they looked clean, but when they examined the channels of the shaver more closely with a borescope, they could see retained tissue. The study also reported there were some steps in the reprocessing protocol that were not taken. It's hard to know whether people consciously made decisions to not do certain things, or whether they were not well trained. It's a constant reminder of how important every step is in reprocessing, especially cleaning, and it is not one to be shortchanged. Sterile processing is complicated, and personnel need to be well trained, in addition to having the time and the right tools to perform their work properly.  And in this case, technology in the form of a borescope was used to see if the device was really clean -- that's a step that isn't on the radar in many sterile processing department. Technicians must realize that retained tissue may be there even if they visually examine the device -- it's something people hadn't thought about before."

The discovery of the retained bioburden in the suction channel of arthroscopic shaver handpieces despite reprocessing according to the manufacturers instructions was the "most consequential aspect of this outbreak," according to Tosh, et al. (2011) who note, "The bioburden was not apparent on routine examination and was detected only through endoscopic visualization of the suction channel. Hospital X performed endoscopic evaluation of the shaver handpieces by other manufacturers at other facilities within their system and found retained bioburden, which suggests that this problem is not specific to this institution or to a specific manufacturer."

Infections have been blamed on faulty reprocessing of medical devices, but now, there is renewed focus on device design as being a potential culprit in outbreaks. "As hospital epidemiologists, we are not the ones who put our hands on these devices, but it's the clinicians who use them and the technicians who reprocess them, and they are likely to put pressure on the manufacturers to keep in mind the cleaning, disinfection and sterilization processes when they are designing the devices and instruments," Dembry says. "It's not just about accomplishing the task that the device is meant for but how easy or how hard it is going to be to reprocess. Scopes are very expensive so they are not buy one, use it and throw it away; we're not talking about trocars, we are talking about very intricate devices that are very important to what is performed surgically. Right now, these devices are designed for doing the job, for the surgeon to take care of the patient, not necessarily balanced for ease of the ability to reprocess them."
Dembry continues, "It's a chicken-or-the-egg situation, but it's also a question of device-related technology being farther ahead of our ability to manage it. There is so much good that comes from the use of these devices; if there was simply rampant disregard for following the manufacturers' recommendations that had dire consequences 100 percent of the time, there would be a lot more infections. It's a testament to, for the most part, of people in sterile processing doing the right thing. The cluster reported in the study reminds us about the dangers of biofilms and bioburden. The retained tissue became a place for bacteria to live there, protected. Unfortunately, our technology isn't advanced enough to prevent biofilm formation, and so biofilms play a role in a lot of our device-related infections, whether catheter-related urinary tract infections or central line-associated bloodstream infections."

The hospital's response to the outbreak in the Tosh study included closing the OR pod where the majority of arthroscopic procedures were performed, replacing the arthroscopic instruments, returning to use of more rigid suction tubing for arthroscopy, and changing the instrument reprocessing protocols. According to Tosh, et al. (2011), instrument reprocessing protocols were adjusted to include routine endoscopic evaluation of reprocessed shaver handpieces to ensure that the suction channel did not contain residual bioburden; use of a non-bristled brush to clean the lumen of the arthroscopic inflow/outflow cannulae; submerging the shaver handpiece in enzymatic solution for 10 to 15 minutes during gross decontamination; capping the distal end of the arthroscope camera and shaver handpiece power cord before submersion in enzymatic solution; prohibiting the storage of surgical instruments in areas outside of the designated storage room; and reinforcing policies restricting flash autoclave use to instances when a surgical instrument becomes contaminated during a procedure and needs to be quickly reprocessed for use in that procedure.

In addition, the gross decontamination room was redesigned to improve workflow, instrument reprocessing staff received annual training and certification, and tracking of the individual instruments used in each surgery was initiated. The investigators reported that no further cases occurred among patients who underwent arthroscopic procedures after these changes were initiated.
Dembry points to these interventions and emphasizes the need for constant training and education. "I think competency evaluation is very important but in these difficult financial times, training and education is the very thing that can be cut from the hospital's budget," she says. "It takes time to actually review and check off sterile processing personnel's competencies, and that is another challenge."

Dembry adds that addressing the nature of the work could go a long way toward improving sterile processing department functionality. "It's like when we're driving a car -- we're all a few seconds away from having an accident but why doesn't it happen? I think it's because most of the time it's going to be okay, but that doesn't mean that sometimes we're not paying attention," she says. "When there's an accident we realize we could have done better... but would we all benefit from driver's education every year and signing off on our competencies? I think we would all balk at that but it probably wouldn't hurt. It's like that in a sterile processing department where things become automatic. As was mentioned in The  TODAY Show segment, it's a tedious job that can become routine, and the volume is tremendous. And even if the volume were less, you still have to be concerned about tuning out when the process becomes very routine -- did you remember to check that scope and the suction channels after you cleaned it to make sure not only was it visually clean, but did you look at it with the borescope? Again, it's like driving home and it's so routine and you don't remember any of it. I am not trying to dismiss the problem, but this is a human factor that comes into play when mistakes are made."

At Dembry's hospital, an instrument tracking system was installed, she says, "so if we recognize that something has gone awry, even if it is after the fact that a sterilizer maybe didn't run the way it was supposed to, even thought it was all signed off, we can go back and track exactly what instruments in those loads might have been used on patients, which has often been the difficulty in the past." Dembry adds, "We can look at the documentation to try to see why it happened -- people don't mean to skip steps, but I think sometimes they don't understand the importance of what they are doing, or they are rushed, they think they did it and they didn't, or they automatically sign their initials to the printout because that's what they always do and they didn't actually read the printout. We recognized some years back when we had an issue with a sterilizer failure -- there wasn't enough light around the sterilizer for people to really read the printouts well. So one of the solutions was to improve the lighting in the sterile processing department.  We must look at what introduces factors such as fatigue, what makes it hard for people to do their jobs correctly. I doubt there are sterile processing technicians who get up in the morning and say, 'Today is Tuesday, and on Tuesdays I don't document my work.' I don't know anyone who does that; I'm sure they all get up in the morning and think, 'I hope everything goes okay, I hope I don't make any mistakes.'  The reality is that they are also human and therefore fallible.  As the Tosh study indicated, the hospital did some redesign of the flow in the decontamination room, so sometimes we have to look at the space that people are working in. It's often some basic human engineering that can solve the problem --  how can we make it easier and more likely people will do the right thing and less likely or harder to do the wrong thing."

It may also take collaboration and communication to build a better system. "It's always my hope that sterile processing personnel want hospital epidemiologists and infection preventionists  to come down to their department," Dembry says. "And if we don't do so on our own, they should invite us.  They are usually happy to see us because no one goes to see them. You can get a lot of information by saying, 'Walk me through the point where the instruments come down so I can see what happens,' and then they are usually open to ideas of how to make things better. It is getting out of our silos and creating partnerships. It's not about telling them how to do their jobs, but we can be another set of eyes and look at processes differently. At the same time we can be their advocates and try to get changes made for them -- not necessarily always more people or more sterilizers -- it might be a redesign of their area so they are less likely to make errors. It's about a team approach to finding solutions."

Reference: Tosh PK, Disbot M, Duffy JM, Boom ML, Heseltine G, Srinivasan A, Gould CV and Berríos-Torres SI. Outbreak of Pseudomonas aeruginosa Surgical Site Infections after Arthroscopic Procedures: Texas, 2009. Infect Control Hosp Epidem.  Vol. 32, No. 12. December 2011.