- Order of endoscope reprocessing
- Point-of-use (bedside) treatment → leak test → manual cleaning → high-level disinfection (or sterilization) → drying → storage (ANSI/AAMI ST91).
- Point-of-use treatment
- Bedside pre-cleaning right after the procedure — wipe the insertion tube and flush channels — so soil stays moist and does not dry into biofilm.
- Leak test
- A pressurized check for breaches in a scope's fluid-tight barrier, done before immersion; angulate the bending section and watch for a continuous stream of bubbles.
- Manual cleaning
- Brushing every accessible channel and flushing with enzymatic detergent to remove organic soil before disinfection; the most critical, non-skippable step.
- Enzymatic detergent
- A cleaner whose enzymes break down blood, mucus, and protein; generally not antimicrobial, so it is freshly prepared and discarded after each scope.
- High-level disinfection (HLD)
- A process that destroys all microorganisms except large numbers of bacterial spores — the minimum for semicritical flexible endoscopes.
- Glutaraldehyde
- A high-level disinfectant that usually must be activated and concentration-verified before use; vapors irritate eyes and airways, so it needs ventilation and a covered basin.
- Ortho-phthalaldehyde (OPA)
- A high-level disinfectant (0.55%) that needs no activation, has a shorter contact time, and causes less respiratory irritation than glutaraldehyde.
- Peracetic acid
- A sporicidal liquid chemical agent used for high-level disinfection or liquid chemical sterilization; processed scopes are used promptly (no sterile packaging).
- Minimum effective concentration (MEC)
- The lowest concentration at which a reusable high-level disinfectant still works; verified before each use with a test strip — the MEC result, not the date, governs use.
- Contact time
- The validated exposure time at the labeled concentration and temperature that achieves the disinfectant's claimed microbial kill; it must be observed exactly per IFU.
- Final rinse (after HLD)
- Rinsing with sterile or bacteria-free filtered water (often a 0.1–0.2 micron filter) to remove disinfectant residue that could injure mucosa.
- Forced-air drying
- Drying channels with pressure-regulated instrument-grade or HEPA-filtered air for at least 10 minutes; residual moisture lets waterborne bacteria multiply.
- Automated Endoscope Reprocessor (AER)
- A machine that automates disinfectant exposure, rinsing, and channel perfusion with documented parameters — but manual cleaning must still be done first.
- Borescope inspection
- Using a thin lighted scope to look inside channels for retained soil, scratches, or peeling coating that surface inspection cannot reveal; failures go back for reprocessing or repair.
- Visual inspection (after cleaning)
- Lighted-magnification check before disinfection; any residual soil or moisture means cleaning is incomplete and the scope is re-cleaned.
- Channel brush
- A correctly sized single-use brush passed fully through a lumen until bristles exit clean; discarded after one scope and removed from service if frayed.
- Low-temperature sterilization
- EO or vaporized hydrogen peroxide used for heat- and moisture-sensitive flexible endoscopes instead of steam, which would damage them.
- Ethylene oxide (EO) limitation
- Effective for heat-sensitive scopes but requires a lengthy aeration period to drive off toxic residual gas before the device is safe to use.
- Spaulding classification
- Ranks devices by infection risk: critical (sterilize), semicritical (high-level disinfect minimum), noncritical (low/intermediate disinfect).
- Semicritical device
- A device that contacts intact mucous membranes or non-intact skin but not sterile tissue — e.g., a flexible GI endoscope; needs high-level disinfection at minimum.
- Critical device
- A device that enters sterile tissue or the vascular system; must be sterilized.
- Noncritical device
- A device or surface that contacts only intact skin (e.g., a reprocessing countertop); needs low- or intermediate-level disinfection.
- Sterilization vs. disinfection
- Sterilization destroys all microbial life including spores; disinfection eliminates most pathogens but may not destroy large numbers of spores.
- Bacterial endospore
- A dormant, highly resistant survival structure (Bacillus, Clostridioides) that resists heat, chemicals, and drying — the most resistant to chemical inactivation.
- Biofilm
- A community of microbes embedded in a self-produced protective matrix on a surface; it shields organisms from disinfectants, so it must be prevented by prompt cleaning.
- Bioburden
- The number of viable microorganisms on a device before reprocessing; thorough cleaning lowers it so disinfection can succeed.
- Log reduction
- A measure of how much the microbial population drops after a process; each log = a 10-fold reduction.
- Standard precautions
- Infection-control practices applied to all patients — treat all blood and body fluids as infectious and wear appropriate PPE.
- Chain of infection
- Six linked elements (agent, reservoir, portal of exit, transmission, portal of entry, susceptible host) that must all connect for infection to spread.
- Mycobacteria
- Organisms with a waxy, lipid-rich cell wall that resists disinfectant penetration; HLD agents are timed to achieve mycobactericidal kill.
- Microbiological surveillance
- Periodic culturing of reprocessed scopes to monitor whether the reprocessing protocol is removing microbial contamination.
- Duodenoscope reprocessing challenge
- Its recessed elevator and tight crevices trap soil and shield microbes, making it the hardest GI scope to clean.
- Insertion tube
- The long flexible shaft advanced into the patient; it carries the channels and the imaging bundle to the distal tip.
- Control head
- The handle section housing the angulation knobs and the seats for the suction and air/water valves, plus the working-channel entry.
- Bending (angulation) section
- The articulating segment just behind the distal tip that steers the tip up, down, left, and right under control-knob tension.
- Working channel
- The lumen through which accessories pass and suction is applied; heavily contaminated, it must be brushed along its full length.
- Air/water channel
- Delivers air to insufflate the lumen and water to rinse the distal lens during a procedure; separate from the working channel.
- Elevator (forceps raiser)
- A movable mechanism at the distal tip of a duodenoscope that aims accessories; its recess traps soil and needs special cleaning per IFU.
- Duodenoscope
- A side-viewing flexible endoscope with an elevator at the distal tip, used mainly for ERCP.
- Colonoscope vs. gastroscope
- A colonoscope is longer to traverse the large intestine; a gastroscope is shorter for the upper GI tract — both forward-viewing.
- Video endoscope
- Uses a camera (image sensor) at the distal tip to convert optical images to electronic signals, vs. a fiberoptic scope's optical-fiber bundle.
- Distal tip
- The end of the scope holding the objective lens, light-guide lens(es), air/water nozzle, and the working/suction channel opening.
- Detachable accessories
- Air/water valve, suction valve, and biopsy-port cap — removed and separately cleaned, then processed per their own IFU.
- Channel configuration
- Varies by model (air/water, suction/working, auxiliary water, elevator), so reprocessing must follow the model-specific IFU.
- Unidirectional workflow
- Scopes move one way — soiled receipt → cleaning → disinfection → drying → storage — and never travel back against the dirty-to-clean current.
- Decontamination room pressure
- Kept at negative pressure so air flows inward, containing aerosols and chemical vapors generated during cleaning.
- Clean workroom pressure
- Kept at positive pressure relative to adjacent spaces so contaminated air cannot infiltrate the disinfection/packaging area.
- Air changes — decontamination
- A minimum of 6 total air changes per hour (ANSI/ASHRAE/ASHE 170, referenced by ST91).
- Air changes — clean workroom
- A minimum of 4 total air changes per hour (ANSI/ASHRAE/ASHE 170).
- Relative humidity ceiling
- Processing areas are kept at a maximum of 60% relative humidity to discourage microbial growth and condensation.
- Temperature range (processing area)
- 60–73°F (about 16–23°C) per ANSI/ASHRAE/ASHE Standard 170, as directed by ST91.
- Three-sink decontamination
- ST91's ideal: three sinks dedicated to leak testing, manual cleaning, and critical rinsing.
- Two-room separation
- ST91 prefers separate decontamination and HLD rooms; a pass-through window is used when only one room is feasible.
- Eyewash station
- Must be reachable within about 10 seconds of unobstructed travel from the cleaning area, because irritant chemicals can splash the eyes.
- Storage cabinet distance from sink
- Storage cabinets are sited at least 3 feet from any sink to protect dry scopes from splash and aerosol contamination.
- ANSI/AAMI ST91
- The primary standard for flexible and semi-rigid endoscope processing in health care facilities (2021 edition).
- Pseudomonas aeruginosa
- A waterborne organism that thrives in moisture and biofilm — classically linked to inadequately dried scopes and contaminated rinse water.
- Event-related sterility
- A terminally sterilized, packaged scope stays ready for use as long as the sterile barrier is intact and storage conditions hold — not a fixed expiry date.
- Drying/storage cabinet
- Stores HLD scopes hanging vertically, distal tip down, in HEPA-filtered circulating air; an active cabinet also force-dries channels.
- Vertical hanging storage
- Scopes hang straight and free (not coiled, not touching walls/neighbors) so channels drain and air-dry and surfaces are not abraded.
- Transport container (soiled)
- A rigid, closed, leak-proof, puncture-resistant, biohazard-labeled container; reprocessed before it can carry a clean scope.
- HLD vs. sterilized storage
- An HLD scope hangs unwrapped in the cabinet; a terminally sterilized scope is kept inside its intact sterile barrier package.
- Maximum storage time (hang time)
- The longest a processed scope may be stored before reprocessing, set by a facility multidisciplinary risk assessment (transport and storage conditions are inputs).
- Dropped or damaged scope
- Removed from service for functionality and damage assessment before any further use, since damage can harbor microbes or indicate a breach.
- Cabinet length requirement
- The cabinet must hold the full extended scope length; if too short, the tip rests on the floor, trapping moisture and risking damage.
- Compromised ready-to-use status
- A scope removed from the cabinet, brought into a room, and handled (even if the case is canceled) must be reprocessed before storage or use.
- Loose-loop transport
- The insertion tube and umbilicus are laid in wide, loose loops without sharp kinks to protect internal channels and fiber bundles.
- Traceability
- Linking each specific scope to the patient, procedure, reprocessing method/equipment, and staff member — so a lookback/recall can identify exposed patients.
- Unique device identifier
- A per-scope identifier (not just model number) that distinguishes identical scopes when investigating use, reprocessing, repairs, and recalls.
- Recall (lookback)
- Identifying every patient exposed to a particular scope during a defined window when a reprocessing or HLD failure is later discovered.
- Preventive maintenance
- Proactive, manufacturer-specified servicing and inspection at defined intervals to catch wear before failures occur — vs. reactive repair.
- Borescope inspection frequency
- Recommended by ST91, but the individual facility sets the frequency as part of its quality program.
- Repair return protocol
- Log the repair, then reprocess and leak test the scope per IFU before it re-enters clinical use.
- Loaner scope tracking
- A borrowed scope is logged under a unique identifier with full reprocessing and patient-use records, just like an owned scope.
- Function check
- A post-reprocessing test confirming the scope's components operate correctly and it is safe for patient use before storage.
- RFID tracking
- Radio-frequency tags that auto-document a scope's usage and reprocessing history, reducing manual documentation errors.
- Human factors (in reprocessing)
- How workload, fatigue, interruptions, design, and culture affect a technician's ability to perform every reprocessing step correctly.
- Cognitive load
- The demand on working memory during a long sequential task; overload increases the chance of skipping a step such as channel brushing.
- Fatigue (patient-safety issue)
- Reduced vigilance late in a shift that leads to skipped or rushed steps, leaving residual soil or inadequate disinfection on a patient-ready scope.
- Interruptions / distractions
- Phone calls and foot traffic that cause a technician to lose place in the step sequence; controlled with distraction-free zones and a float staffer.
- Competency verification
- Documented, hands-on assessment for each specific scope make/model and its connectors and cleaning-verification procedures — not a generic sign-off.
- Just culture
- Responding to an error by correcting the system conditions that allowed it while coaching the individual, supporting honest near-miss reporting.
- Pictorial job aids
- Step-by-step visual instructions at the sink that lower memory demand by giving in-context cues for each step.
- Production pressure
- Throughput demands that exceed what careful processing allows, pushing staff to shortcut time-dependent steps.
- Standardized nomenclature
- Consistent component names and unambiguous steps that reduce confusion and inconsistent technique across documents and staff.
- Buddy-check
- An independent second-person verification of critical steps (brushing, inspection) to catch individual slips before they reach the patient.
- Ergonomic workstation
- Adjustable-height sinks, anti-fatigue mats, and good lighting/magnification that reduce musculoskeletal strain and support detail-critical visual tasks.
- Sporicidal claim
- A disinfectant's ability to kill bacterial spores; required when a scope was exposed to spore-forming organisms such as Clostridioides difficile.
- Prion precautions
- Enhanced processing for devices possibly exposed to prions (e.g., CJD), because prions resist standard disinfection and sterilization.
- Opportunistic pathogen
- A normally harmless organism that can cause disease in a vulnerable patient — a reason reprocessing reduces ALL microbes, not just known pathogens.
- Air/water nozzle
- The small opening at the distal tip that sprays water to clean the lens and delivers air; flushed and cleaned because debris blocks it.
- Light guide
- The fiber pathway that carries illumination from the light source to the distal tip of the scope.
- Auxiliary water channel
- A separate forward-jet channel on some scopes that irrigates the mucosa; it must be identified and flushed during reprocessing per IFU.
- Particulate / air-quality monitoring
- Routine checks of the processing area's air quality (e.g., particulate, airflow) to confirm the HVAC design keeps performing.
- Pass-through window
- A closable window used in single-room processing areas to move items from the dirty side to the clean side while maintaining separation.
- Chemical storage (ventilated)
- Disinfectants and detergents are kept in ventilated, labeled cabinets to control vapors and prevent reactions.
- Sterile / filtered rinse water
- Final-rinse water that is sterile or bacteria-free filtered (often 0.1–0.2 micron) so waterborne organisms are not reintroduced after HLD.
- Air-pocket removal
- Purging trapped air from channels during manual HLD so the disinfectant contacts every internal surface for the full contact time.
- Delayed reprocessing
- Following the IFU when a scope cannot be cleaned promptly (e.g., keeping soil moist) and documenting the delay, since dried soil is far harder to remove.
- ATP bioluminescence test
- A cleaning-verification method that measures residual organic material (ATP) on a scope as an indicator of cleaning efficacy.
- Cleaning verification
- Objective post-cleaning tests (e.g., ATP, protein, or borescope checks) confirming soil was removed before disinfection.
- Distal-tip protection
- Hanging the tip down and free in storage and using tip protectors in transport so the delicate optics and channels are not damaged.
- Cabinet maintenance
- Routine, documented cleaning and HEPA-filter service of storage cabinets, since dust and overdue filters can recontaminate stored scopes.
- Service history
- A documented record of each scope's repairs, maintenance, and usage supporting quality control and regulatory compliance.
- Individual accountability
- Honestly completing and signing reprocessing documentation, including self-reporting near-misses, within a non-punitive culture.
