2.2 Point-of-Use Treatment & Transport

Point-of-use (POU) treatment is the first step of instrument reprocessing and happens where instruments are used — most often the operating room (OR). Although OR staff usually perform it, POU directly determines whether every later step in CS will succeed. Cleaning is the foundation of the entire process: if an item is not clean, it cannot be disinfected or sterilized.

Why POU Matters: Biofilm

When blood, tissue, and fluids dry on instruments, problems cascade:

1. Biofilm begins forming within minutes. Biofilm is a community of microorganisms that secrete a protective slime called extracellular polymeric substance (EPS) that anchors them to the surface.
2. Dried organic matter hardens and becomes adherent, so cleaning takes far longer.
3. Proteins denature and bond to the metal — even aggressive cleaning may not remove them.
4. Sterilants and disinfectants cannot penetrate dried debris or mature biofilm; a dirty instrument cannot be sterilized.

Critical principle: The longer soil remains, the harder it is to remove. Time is the enemy. A mature biofilm can resist disinfectants and even some sterilization, which is why removing soil early — before it dries — is the entire point of POU.

POU Treatment Steps

At the surgical field (during the case)

1. Wipe instruments with a non-linting cloth or sponge moistened with sterile water to remove blood before it dries.
2. Flush lumened instruments — suction tips, cannulas, and scopes — with sterile water so soil does not dry in channels.
3. Keep instruments moist; do not let them sit uncovered.

After the procedure

1. Remove gross debris by wiping or rinsing.
2. Apply an enzymatic foam, gel, or spray if transport will be delayed — these products keep soil soft and moist.
3. Open all hinged instruments (hemostats, needle holders) so solution contacts box locks.
4. Disassemble multi-part items per the manufacturer's Instructions for Use (IFU).
5. Separate sharps and delicate items from heavy instruments to prevent injury and damage.
6. Cover with a moist towel or keep the enzymatic product applied for transport.

The saline trap

Never use saline (sodium chloride) to soak, rinse, or keep instruments wet. Saline is corrosive to stainless steel and causes pitting and rust that permanently damage instruments. Sterile water or a labeled enzymatic pretreatment product is the only acceptable choice — this is a frequently tested CRCST point.

Transport requirements

Special Considerations

Lumened instruments

Channels and lumens are the hardest areas to clean and the most prone to biofilm. Flush every lumen with sterile water or enzymatic solution immediately after use. During later cleaning, use a brush sized to contact the full inner diameter — a brush that is too small leaves a soil ring.

Powered and battery instruments

Remove batteries or disconnect power before transport, protect delicate components from impact, and never immerse a powered handpiece unless the IFU specifically allows it. Improper handling can destroy precision parts.

Endoscopes and robotic instruments

Flexible endoscopes require bedside (POU) precleaning — wiping the insertion tube and flushing channels with enzymatic detergent — before leak testing and manual cleaning. Robotic instrument arms have manufacturer-specific flushing and positioning steps; skipping them can permanently damage the device.

Contaminated sharps

Blades, needles, and broken instruments go into a labeled sharps container at the point of use. Never transport loose sharps in an open tray.

Worked Scenario and Common Traps

Scenario: A surgical case ends at 11:00. The tray sits uncovered on a back table until 1:30, when it finally reaches decontamination dry, with crusted blood in the box locks. What went wrong? POU treatment was skipped: no enzymatic foam was applied, hinges were left closed, and transport was delayed about two and a half hours. Dried blood and forming biofilm now make cleaning far more difficult and threaten sterilization.

Common traps tested on the CRCST exam:

• Believing POU "disinfects" or "sterilizes" — it does neither; it only removes gross soil and keeps items moist.
• Using saline or tap water to soak instruments instead of sterile water or enzymatic product.
• Transporting instruments closed or stacked, trapping soil in hinges.
• Treating the 30-minute guideline as a hard regulatory limit — it is a best-practice target; the true rule is "keep moist and transport promptly."
• Allowing the surgeon or scrub nurse to rinse instruments in saline at the field because it is "already on the table" — this is the single most common cause of avoidable instrument corrosion.

Remember that point-of-use treatment is a shared responsibility: the CS technician depends on the OR team to perform it correctly, and educating OR staff about biofilm and the saline trap is part of a strong sterile-processing program. Documentation that captures the time a case ended and the time the tray reached decontamination helps the department identify when delays are recurring and gives leadership the data needed to fix workflow problems before they damage instruments or compromise patient safety.