Flawed From the Start: Why Many IFUs for Surgical Instruments Fail in Real-World Sterile Processing

Cori L. Ofstead, MSPH; Brandon M. Gantt, MHA, CRCST, CHL, CER, LSSGBH; and Jill E. Holdsworth, MS, CIC, FAPIC, NREMT, CRCST, CHL, an infection preventionist in Atlanta, Georgia.

Manufacturer instructions for use (IFUs) often appear precise on paper but often fall short in practice. A recent study highlights how unrealistic IFUs for orthopedic and neurosurgical instruments routinely overlook real-world limitations, resulting in inconsistent cleaning, confusion among staff, and serious risks to patients.

This research, recently published in American Journal of Infection Control and presented at the 2025 Healthcare Sterile Processing Association (HSPA) Annual Conference & Expo held in Louisville, Kentucky, from April 26 to 29, Cori L. Ofstead, MSPH, lead author, and her colleagues, Brandon M. Gantt, MHA, CRCST, CHL, CER, LSSGBH, manager of the sterile processing department education and training at Emory Healthcare; and Jill E. Holdsworth, MS, CIC, FAPIC, NREMT, CRCST, CHL, an infection preventionist in Atlanta, Georgia, explained how borescopes offer a critical line of defense.

Another presentation by Ofstead and Holdsworth was presented at the 2025 Association for Professionals in Infection Control and Epidemiology (APIC) held in Phoenix, Arizona, from June 16 to 18.

Their study, “Unseen threats: Lumens 2.0 study reveals the hidden challenges of cleaning lumened surgical instruments conducted at a major academic medical center” has uncovered a critical patient safety concern: 100% of lumened surgical instruments inspected contained retained debris or discoloration, even after cleaning protocols were followed exactly as outlined in manufacturer IFUs.

Using borescopes, researchers conducted 117 inspections of 40 instruments used in orthopedic, neurosurgical, and ear, nose, and throat (ENT) procedures. After initial cleaning, every instrument still showed evidence of contamination, including:

• Rust-colored or orange patches in 95% of instruments
• Chunks of yellow, brown, or black debris in 88%
• Fibrous material like lint or brush bristles in 73%
• Persistent contamination after up to 3 rounds of recleaning

This study confirms what many infection preventionists have long suspected: adherence to IFUs is no guarantee of internal cleanliness. Architectural complexity—characterized by tight lumens, dead ends, inaccessible grooves, and hidden cavities—renders many surgical instruments effectively uncleanable using standard methods.

For infection prevention personnel, these findings represent an opportunity and a call to action. Borescope inspections, enhanced staff training, and interdisciplinary collaboration with sterile processing teams must become routine. Proactively identifying high-risk instruments and advocating for more transparent IFU development can help mitigate infection risks before harm occurs.

For manufacturers, the message is equally urgent. Real-world testing of device cleanability should become an integral part of the design and regulatory process. Instruments must not only perform surgically—they must also be cleanable in actual hospital conditions. Vague or contradictory IFUs, or those that require impractical tools or techniques, are not just inconvenient; they are unsafe.

Collaboration between infection prevention, sterile processing, and industry partners is essential to redefine clean and protect patients.

Read on to learn more from the authors. This is the third installment of 4 of the interview conducted by Infection Control Today^® (ICT^®) with Ofstead and 2 coauthors. Please find the first installment here. The second is here.

ICT: What are the most common limitations or flaws you've found in current manufacturer IFUs for orthopedic and neurosurgical instruments?

Cori L. Ofstead, MSPH: The device design doesn't appear to have taken cleaning into consideration. When you look at an IFU sketch of a device, the lumens and dead-ends look smooth and simple, but when you look inside with a borescope, it doesn't look like the IFU drawing at all.

When a technician examines an IFU, they have no way of knowing that the inside of the instrument is nothing like that at all. That is a fundamental problem with IFU, because technicians can't know how complex the instruments are if the IFU doesn’t accurately reflect the device architecture.

Also, some steps are unclear or contradictory, and Jill pointed out one example of this, specifically an IFU that states you must clean the lumen while the valve is open. Then it says to clean it while ‘simultaneously opening and closing [the valve].” How's that a thing? You can't do that—simultaneously open and close a valve while it’s open. During the HSPA presentation, the entire audience laughed when Holdsworth described what the IFU said. It was clear that the audience understood it couldn’t be done as described.

Here's another example of a complex, confusing IFU. It instructs you to brush one end of the instrument 5 times and then brush the other end 4 times. Then, use the water pistol for 60 seconds. And, the instructions are different for each one of the 20 instruments in the tray, even though they’re made by the same manufacturer. How are techs supposed to remember what to do when the directions are different for each instrument? Perhaps we could develop some coaching electronics that display the device and alert the techs that “This one needs to be brushed 5 times here, flushed for 30 seconds on this part, and 60 seconds on this other part.”

But that's the next part of the problem: Have you ever been in sterile processing and used a water pistol, or have you used a hose in your yard where you squeeze the handle while you're watering? Squeezing a handle for 60 seconds is a long time, and those water pistol handles require a certain grip strength. If [the IFU] says to rinse for 60 seconds, and let's say there are 20 attachments in the tray, and if you must stand there for a whole minute for each end of the instrument, shooting the water pistol in there, are you counting the seconds? Are you watching a clock? Or can you not watch a clock because you have to be watching what you’re doing? I'm not sure how that would work.

Additionally, if you're trying to count in a noisy environment with many distractions, it would be challenging to ensure that you complete each task for 30 or 60 seconds. In any case, processing a tray with 20 instruments, it's going to take a long time to process that tray, and technicians just don't get allocated that much time.

The next part of this answer is that most facilities don't have a wide variety of brushes or different types of detergent. So, they will select a standard set of brush sizes and a standard detergent, or possibly 2 detergents for manual cleaning. For that tray we showed during the presentation, there were 11 or 12 different sizes of brushes that were supposed to be used, and when you take them out of the packages, you can't tell them apart. How would the technician be aware that this instrument is supposed to be cleaned with a 3.16 mm brush? This other instrument is also supposed to be cleaned with a 4.5 mm brush. A person looking at a brush can't tell if it's a 3 mm, 3.5 mm, or 4 mm, and once it is out of the package, there’s no label on it, so I can't see how anybody ever thought through how this would work in a real hospital.

The FDA should require the manufacturers to conduct real-world assessments. So, put the instruments in a real department and see if the people can comprehend and follow the IFU, and determine whether the instructions are correct. What happens when you follow the IFU? Do you have the stuff it says to use during cleaning? Can you figure it out?

And fast-forward to what both the lumens pilot with Steve and the Lumens 2.0 study showed: Following the IFU doesn't work, and the recommended steps for cleaning don’t work to remove visible soil, chunks of tissue, and other debris. How they got FDA clearance is baffling to me. And it tells me that they must not have used the instruments for real procedures and had real technicians trying to get them clean. Maybe they used artificial test soil. Maybe they cleaned it in a research lab, so it wasn't used on messy procedures, and perhaps they did the pretreatment right away, so there were no delays in getting it down to sterile processing for cleaning. That debris gets hardened in there, and there has been no real-world confirmation that the cleaning methods described in manufacturers’ IFUs work.