Six steps to a scope’s long life

1. Pre-cleaning

2. Leak testing

3. Cleaning

4. Disinfection/ Sterilization

5. Drying

6. Storage

Let’s look at each step.

All gross contaminants should be wiped from the endoscope before debris is allowed to dry. All channels including suction/biopsy channel and air/water channel must be flushed thoroughly to ensure any debris is dislodged from the distal tip of the air/water nozzle tip and to allow the diluted enzyme detergent to begin to break down bioburden on internal channels.

Endoscopes need to be transported in a rigid container alone, with no accessories that may cause damage. The rigid container protects the endoscope from outside damage and minimizes the risk of exposure of contaminants and body fluids. Never stack endoscopes. A special medical supply container does not need to be purchased; only one that is large enough to contain the scope, while maintaining its natural curve (minimum recommended size: 24 inches diagonally). Do not bend any endoscope into a radius tighter than that found in its shipping case. In general, a minimum 10-inch bend radius applies.

Sharp edges and metal parts of one scope may damage the scope above or below it. All accessories must be separated and reprocessed independently, since they are sharp.

Manual leak tester

Most of an endoscope’s internal components are not made to be chemical- or fluid-resistant. The most important preventive measure in avoiding fluid invasion is leak testing the scope after every procedure and before cleaning. For leak testing to be effective, it’s helpful to understand the mechanics involved and how to do it properly. Always leak test and pressurize the endoscope before immersing it in water and before cleaning. It’s important to check the integrity of the seals and to detect any damage before the device is completely immersed. By identifying minor leaks, major fluid invasion is prevented, and thousands of dollars can be saved.

A manual or electric leak tester is used to introduce air and pressurize the scope. Electric powered leak testers are preferable because they provide a continuous flow of air that prevents fluid from invading the scope during inspection. If using the hand-operated leak tester, extra care and time must be taken. If there is a drop in the pressure gauge, re-pressurize the scope. It’s worthwhile to pay attention to even a slight loss of pressure on the gauge, since this can help identify a small leak. If caught early, this results in a much smaller repair bill than the cost of a total fluid invasion.

Mechanical leak tester

A dry or wet leak test may be performed. During a dry leak test, the gauge on the hand-operated leak tester is observed for loss of pressure. In a wet leak test, the endoscope is submerged in water, up to and including the connection with the leak tester. Pressure must be maintained to ensure there is no fluid invasion. Every area of the scope is checked for the presence of air bubbles. Whichever leak test method is used, follow the device manufacturer’s instructions. Always allow sufficient time to identify a problem.

To perform a wet leak test, fill a properly sized sink with fresh, clear water. Do not use colored or soapy enzymatic cleaners; they will distort the interpretation of the leak test. The sink must be large enough to immerse the entire scope, including the light guide connector and the connection with the leak tester. If the scope is not completely immersed, the areas out of the water cannot be identified for a potential leak that may eventually contribute to a major fluid invasion.

Video endoscopes have a series of rubber-coated remote switches that are notorious for leaks. The rubber may dry and crack, and the switches can be damaged by rough treatment or sharp accessories. Manufacturers recommend that the switches be depressed during the leak test, to provoke an existing crack and to help visualize a leak. These switches need periodic lubrication to restore moisture and retard cracking. Check the device manufacturer’s guidelines.

One of the ways to clean surgical soils such as proteins and lipids is with enzymatic agents. It’s important to use an enzymatic detergent that is labeled for use on endoscopes, to ensure that it’s compatible with all the component materials. Some neutral pH enzymatic cleaners contain proteases, which break down surgical soils, such as the proteins in blood. However, proteases have a tendency to degrade other enzymes (such as lipases) that are blended with them in so-called multi-enzymatic formulations. To be sure of cleaning efficacy for all soil types, consider cleaning formulations that blend two protease agents with surface active agents
(surfactants). This combination has an exceptional ability to remove soils and emulsify fats. (NOTE: If the same formulation is also being used in automated washers, choose an enzymatic formulation that is low-foaming. Too much foam can interfere with the machine’s operation and cleaning effectiveness.)

Manual washing

Dilute the enzymatic detergent according to the instructions and mark the sink to ensure the proper amount is used each time. Follow label instructions for the temperature of the water and the soak time to allow the full benefit of the enzyme to break down bioburden. It’s also important to thoroughly rinse the endoscope with fresh water, including adequate rinsing of all channels, before disinfection/sterilization. Freshly prepared water is used for each endoscope that is cleaned. Avoid abrasive agents; they can be damaging to endoscope materials. If the tap water contains minerals like iron, calcium and magnesium, distilled water should be used for the final rinse, since some mineral deposits can harm endoscopes. In addition, select appropriately sized cleaning brushes that will contact all the internal surfaces of the channel and dislodge all debris from the channel wall.

Brushes with high quality nylon bristles are preferred. Reusable brushes need to be disinfected between uses, and replaced as they become worn. If brushes are labeled for single use, discard after use. When brushing the channels, keep the endoscope submerged under water to prevent aerosolization. It is imperative that all channels including auxiliary water channels, water jet channels, and elevator guidewire channels are accessed. Avoid pulling downward on the insertion tube when cleaning. Over time, this practice can cause the bending rubber to separate from the outer sheath, allowing fluid invasion. A short, rounded motion is preferred. It is important to inspect bending rubber components for potential trouble.

Refer to the endoscope manufacturer for disinfection and/or sterilization instructions. The United States Food and Drug Administration (FDA) requires device manufacturers to provide reprocessing instructions and they must be followed to assure the desired outcome. Each facility will define their policies and procedures based on these instructions. The standards of practice should be the same throughout the facility.

If automated reprocessing equipment is used, the endoscope must be placed carefully into the processor. Any adapters required for the processing system must be used correctly, following the instructions of the processor manufacturer. When the cycle completes, the endoscope should be removed immediately.

The Society of Gastroenterology Nurses and Associates (SGNA) recommends that all channels be flushed with 70 percent isopropyl alcohol at this point, to assist with drying, and be air dried to remove any residual water left in the channels after reprocessing. The exterior of the endoscope should be dried with a soft, lint-free towel, and all removable parts thoroughly dried. The endoscope is now ready for use on a patient or to be put into storage.

Valve scope brushes

Correct storage requires a controlled environment to prevent contamination, damage to device surfaces and moisture build-up in the cabinet. Storage surfaces must be non-porous. The storage area should be inspected for sharp and jagged edges that could damage endoscopes. Endoscopes need to be hung vertically in a well-ventilated, dust-free cabinet, to facilitate drying (with caps, valves, and other detachable components removed as per manufacturer instructions). The distal tip should hang freely. The scope sheath should not contact cabinet edges. The insertion and light guide tubes should not be coiled – this might cause moisture to pool in the coils. Angulation locks should be in the OFF position. Videoscopes should be stored with the fluid-resistant cap OFF, to aerate the scope. However, fiberscopes are recommended to be stored with their ETO cap attached, since this permits an open avenue for air circulation to the internal channels. Removable parts, such as valves and buttons, should not be attached to the scope during storage. This lowers the risk of trapping liquids inside, and helps to dry the channels and openings. Also, the storage cabinet should be reserved for endoscopes only.

It’s important that we plan for routine preventive maintenance and pay attention to all our endoscopes. For example, before each procedure, check the air, light, water, suction and image, before exposure to any fluids. Also verify that the light guide prong is tight and that a leak test has been performed and passed. Periodically, re-moisturize the rubber components and check the angulation specifications. And use bite blocks before and during procedures to prevent insertion tube damage.

In addition, if you avoid all the "don’ts" (don’t buckle the insertion tube; don’t coil the scope too tightly when handling or transporting it; don’t use accessories unless they’re in good working condition; don’t force accessories into channels; don’t use foreign objects to free clogs), you will have endoscopes with longer working lives and better returns on the investment your facility has made. Most importantly, though, you’ll be contributing to better patient care.

Introduction and Vendor Chart