AJIC Biofilm Research

Biofilm Formation and the Increased Risk of a Surgical Infection Biofilms that remain on or inside of surgical instruments after reprocessing have long been a suspected source of surgical infections. Over the past few years several tragic events have served to prove the link between biofilms on instruments and surgical infections. One of the more recent, well-publicized events occurred last May at a hospital in Colorado when contaminated surgical instruments posed a problem.¹ A month after the initial story made headlines, a report was released that cited biofilms as the probable cause of the contaminated surgical instruments. According to that report, “Biofilm appears to be behind the infection breakout that last month forced the Denver hospital to suspend all surgeries for nearly a week. A trail of evidence points to improper instrument cleaning practices and the hidden menace known as biofilm.”² The report that came out in June, 2018 pointed out that:

• When surgical site infections are linked back to surgical instruments, biofilm is likely a root cause.
• The infection outbreak spanned nearly 2 years, from July 21, 2016, to April 5, 2018. Whatever was causing the infections were recurrent and undetectable, telltale characteristics of biofilm.
• Colorado Department of Health officials determined that the infection control breach was due to human error that occurred during "a gap" in the manual pre-cleaning phase — before the instruments underwent heat sterilization. Staff wiped down, soaked and scrubbed certain spine and orthopedic instruments, but apparently not well enough. The instruments likely still contained biofilm when they were sent along for automated cleaning and heat sterilization.³

Biofilm is an organized colony of bacteria and extracellular material (e.g., proteins, glycoproteins, and carbohydrates) that includes both viable and nonviable microorganisms. This collection of microbial cells is covered by a polysaccharide matrix that tightly adheres to the surface of a surgical instrument. The polysaccharide matrix serves to protect the biofilm from attempts to remove them by ordinary cleaning methods. This protective matrix also helps prevent antimicrobial agents, such as sterilants, disinfectants, and antibiotics, from reaching the microbial cells. According to new research published in the American Journal of Infection Control (AJIC), and the journal of the Association for Professionals in Infection Control and Epidemiology (APIC), eliminating biofilm on surgical instruments can help reduce dangerous Staphylococcus aureus (S. aureus) pathogens. As the article demonstrates, any and all steps taken to reduce the presence of S. aureus on your surgical instruments after decontamination, cleaning and reprocessing will help in reducing your patients’ risk of contracting a surgical infection.⁴ “Attenuation of S aureus transmission is an important target for postoperative infection prevention. This study has identified S aureus ST 5 is a pathogenic strain associated with increased risk of transmission, greater strength of biofilm formation, increased antibiotic resistance, and increased risk of postoperative infection development.” The study went on to state that “Up to 7 percent of patients undergoing surgery continue to contract at least one postoperative infection."⁴ When it comes to removing biofilms on reusable medical devices and surgical instruments in your facility, the current AAMI guidelines state: 6.3.1 Handling of instruments during surgical procedure Throughout the surgical or invasive procedure,

1. a) Instruments should be wiped, as needed, with sterile moistened surgical sponges to remove gross soil; and
2. b) Cannulated instruments or instruments with lumens should be irrigated with sterile water, as needed, without creating aerosols.⁵

These AAMI guidelines are very specific for several important reasons: Blood, other bodily fluids, and saline are highly corrosive and can cause pitting of instruments if not quickly removed. Organic debris can be difficult, if not impossible to remove from the surface of an instrument if allowed to dry. When a biofilm formation dries on an instrument, direct friction and/or oxidizing chemicals are required to remove the biofilm. ⁶ At best, they will contribute to staining. Any organic debris, including biofilm that remains on an instrument after cleaning can prevent 100% bacteria kill during the sterilization cycle. Over time, cannulated instruments or instruments with lumens can become obstructed with organic material if not removed on every reprocessing cycle. Irrigating these instruments with sterile water at the point of use helps to remove the organic debris before it has time to dry, thus making removal easier and improving device longevity. Preparation for decontamination and cleaning of instruments should begin at the point of use. To prevent the formation of biofilm and to reduce the risk of corrosion, cleaning and decontamination should occur as soon as possible after instruments and equipment are used.⁷ Protecting patients from a dangerous, painful and costly surgical infection caused by a contaminated instrument is the goal of every CS/SPD team member. When it comes to patient outcomes, 2018 APIC President Janet Haas, PhD, RN, CIC, FSHEA, FAPIC made this observation: “To improve outcomes for our patients, we need to continually assess and make process improvements to ensure that we do the right thing for every patient, every time.”⁸ Protecting your patients from harm caused by a contaminated instrument starts by following manufacturers’ published cleaning and reprocessing IFUs. Even more important than following the manufacturers’ published IFUs is to demand IFUs that have been validated by independent laboratory testing using AAMI and FDA test protocols. By using instruments with validated IFUs you and your staff can have the documented assurance of providing clean, sterile, moisture-free instruments for every patient, every time! 1. NBC News 9, Denver, Colorado. 2. Outpatient Surgery, June 5, 2018 3. Op. Cite. 4. “High-risk Staphylococcus aureus transmission in the operating room: A call for widespread improvements in perioperative hand hygiene and patient decolonization practices.” American Journal Of Infection Control, October 2018, Volume 46, Issue 10. Randy W. Loftus, MD; Franklin Dexter, MD, PhD, FASA; Alysha D.M. Robinson, BS; Department of Anesthesiology, University of Iowa Hospitals and Clinics, Iowa City, IA. 5. AAMI Standards, www.aami.org/standards 6. Op. Cite. 7. Op. Cite. 8. APIC Press Release December 12, 2018 www.apic.org