Endoscopic Instrument Care
On this page
Direct answer
Flexible endoscopes are heat-labile and can never be steam-autoclaved whole, so they are reprocessed by a strict sequence: bedside pre-cleaning within minutes of withdrawal, leak testing under water, manual cleaning with enzymatic detergent and channel brushing, rinsing, immersion in a high-level disinfectant such as 2% glutaraldehyde or 0.55% ortho-phthalaldehyde, alcohol-flush and forced-air drying, then vertical hanging in a ventilated cabinet. Skipping or shortening any step — especially the manual cleaning — leaves organic soil and biofilm that no disinfectant can penetrate, which is exactly how scope-related infection outbreaks happen. Rigid laparoscopic optics and light cables, by contrast, tolerate steam sterilisation and follow standard CSSD pathways.
What you must remember
- Sequence: point-of-use pre-cleaning, leak test, manual cleaning with enzymatic detergent and single-use brushes, rinse, high-level disinfection (HLD), final rinse, alcohol flush and drying, storage — in that order, unskippable.
- Bedside pre-cleaning: channel flushed with enzymatic detergent and exterior wiped immediately after withdrawal, before soil dries into the channels.
- Leak test: the scope is immersed and gently insufflated; a stream of bubbles from the insertion tube, bending section or umbilical cord condemns it to repair before any immersion proceeds.
- HLD agents: 2% glutaraldehyde (immersion commonly about 20–45 minutes at room temperature per label, and around 10 hours if used as a sterilant) and 0.55% OPA (about 12 minutes at 20°C, per label) — activate, monitor concentration with test strips, and respect expiry.
- Manual cleaning is the microbiological step: disinfection fails on uncleaned channels; brushing all channels with compatible single-use brushes and flushing each port is non-negotiable.
- Drying matters: alcohol flush followed by filtered forced air prevents Pseudomonas and mycobacterial growth in stored channels; wet storage has ended outbreak investigations.
- Storage: hung vertically in a clean, ventilated cabinet, caps and valves removed, handled no-touch; many SOPs require reprocessing before use if storage exceeded about a week.
- Single-use accessories: biopsy valves, brushes and some caps are single-use; duodenoscopes with their elevator channel carry the highest risk and the strictest protocols.
- Traceability: scope identifier, patient, reprocessor cycle and disinfectant concentration recorded for every cycle.
One gastroscope through the department
The scope leaves the patient and is wiped at the trolley while the channel is flushed with enzymatic detergent — two minutes of bedside work that determines everything downstream. At the reprocessing room it passes the leak test: immersed, gently air-insufflated, every bending motion watched for bubbles. Clean and dry, it enters the enzymatic bath, exterior wiped, each channel brushed to size and flushed with detergent, then rinsed of enzyme.
Now the disinfection: into the glutaraldehyde or OPA for the label-specified contact time, channels perfused so the chemical fills rather than merely bathes them, then rinsed with filtered water, perfused with 70% alcohol and dried with forced air. Automated endoscope reprocessors do this reproducibly and print the cycle record, but they clean only what pre-cleaning left cleanable. The scope hangs vertically in the cabinet, its tag reading ready, its traceability entry linking it to the previous patient and today's cycle. Before the next list, the technician verifies the channel test and the storage interval — reprocessing anything stored beyond the department's limit rather than trusting the calendar's word over policy's.
Where students slip
The recurring error is calling the endoscope "sterile" after HLD: high-level disinfection kills vegetative organisms and viruses but falls short of sporicidal sterility, which is why scopes are used against mucosa rather than sterile tissue — and why sterile-cavity use demands a sterilant-level process or a sheath. The second slip is sequence: leak testing after cleaning (immersion of a breached scope destroys it), or disinfection before brushing (protein load inactivates aldehydes and shields microbes). Third, concentration and time: glutaraldehyde is tested with indicator strips and discarded at minimum-use days regardless of appearance, and "a quick dip" is a phrase with no legitimate meaning. Finally, candidates forget drying and storage — the outbreak literature is dominated not by failed disinfectant but by wet, vertically-stored-no-more channels.
Frequently asked questions
Why must cleaning precede high-level disinfection?
Organic soil and biofilm shield microbes from aldehydes and inactivate them; disinfection is only as good as the cleaning beneath it.
When is the leak test performed?
Immediately after bedside pre-cleaning and before any immersion cleaning, so fluid does not enter a breached waterproof layer.
How long does 2% glutaraldehyde high-level disinfection take?
Commonly about 20–45 minutes at room temperature per label, with roughly 10 hours of immersion when used as a sterilant.
How should a processed endoscope be stored?
Hanging vertically, fully dried, in a clean ventilated cabinet with valves removed, and reprocessed before use if storage exceeded the department's interval — commonly about a week.
Are biopsy valves and cleaning brushes reusable?
No; they are single-use accessories, and reusing them reintroduces contamination the entire cycle just removed.