Maximizing flexible endoscope performance

Careful handling and meticulous care can prevent damage such as air/water nozzle blockage, damage to light fiber bundles, cracked C cover or lens, repeated bending rubber damage, and all-fluid invasion. Common repairs include periodic angulation adjustments, bending rubber replacements from wearing, stretching and punctures, and insertion tubes. When reprocessing any endoscope, performing each critical step correctly will help to protect patients, extend the device’s useful life, and keep repair costs down.

Scope repair costs must be analyzed in order to keep them at a minimum. There are many factors that have an impact on repair costs, and it is prudent to investigate each specific repair to identify the cause. Endoscopes may, in fact, be overused on a daily basis, especially when the brand new one arrives in the department. It’s important to have a computer program that will input data on how frequently each endoscope is used. Pertinent information also includes the physician’s "favorite" scope that is used more frequently than the others that hang in the closet and are still part of the inventory. A log that contains purchase dates and model types of the endoscope inventory assists in documenting the age of all endoscopes and determining the timing for replacements.

Tracking the number of times each scope is used is a good way to determine if just a few scopes are routinely used, and if a particular scope has a higher number of repairs. Rotating inventory is important. If scopes are underutilized because they are older models, over-utilization and high repair costs on other scopes can be the justification to budget for additional inventory.

Analyzing repairs on each scope identifies trends and issues that can be addressed, particularly with regard to care and handling. Identifying particular damage will assist in finding a root cause for correcting the trends. Several manufacturers provide preventive maintenance programs that can be conducted on-site. Trends can be identified, and repairs adequately budgeted, based on preventive maintenance programs.

In addition, all scopes that return from repair must be inspected, leak tested and processed before they’re used on a patient. Thorough inspection of the endoscope when they’re returned may reveal inadequate repairs or damage caused during shipment.

Fundamental, but important questions to ask are the following:

• Is the endoscope handled carefully throughout its useful life?

• Are the reprocessing instructions supplied by the device, cleaning chemicals and reprocessor manufacturers always followed?

• Are reprocessing steps skipped because of time constraints?

• Are steps skipped "because we’ve always done it this way?"

• Are the proper connectors used for accessing ALL channels?

• Do staff members rotate through various areas of responsibility in a facility rather than being dedicated to scope handling and reprocessing?

It is recommended by professional organizations and experts that only dedicated and trained people be responsible for handling and reprocessing endoscopes. They must be adequately trained, be knowledgeable about the department’s devices, and pass skill competencies in order to process scopes on a routine daily basis. Many resources are available for training personnel in the step-by-step processes involved in the correct care and handling of scopes and accessories.

Water resistant caps

When an endoscopic procedure is finished, and the light guide tube is removed from the light source, the electrical contact pins on the light guide connector will be very hot. Take care when handling the connector to prevent contact with the outer sheath. These pins can cause indentations known as "snake bites" that may lead to damage and/or fluid invasion because they can melt the sheath material.

Some electrical connectors are not watertight and need to be capped before transport and immersion to prevent fluid invasion. Fluid-resistant caps are applied to the video connector of appropriate scopes to prevent fluid invasion. Fluid-resistant caps with gaskets have a useful life span, since the rubber deteriorates over time. The caps must be inspected regularly to ensure they are intact. To verify that they are working properly to prevent fluid invasion, check:

• The integrity of the O-ring

• The screws, to assure they are snug

• For any evidence of cracks

• The leak tester port (gas vent), to be sure it’s properly aligned

 If moisture occurs in the area of the electrical connector, never plug it into the processor. Do not try to manually dry it, or insert anything into the connector to dry it. Do not use compressed air because there may be too much force and it will cause damage to the electronic components. It’s best to dry it overnight or place it in an aeration chamber.

Fluid invasion of the fiber bundle results in brittle glass fibers. Add excessive bending and torque of the endoscope to a fluid invasion, and what results are broken fibers. Broken fibers are the "black spots" throughout the field of vision that cause a darkening image because there are not enough functioning fibers to carry sufficient light. If the image has become too dark for easy visualization, a fiber bundle replacement is needed.

Be aware that with repeated use and over-bending, the fine wire mesh inside the bending section may fray and the wires may break and work their way through the outer sheath, leaving pin holes through which fluid can enter. The bending section may also be damaged from over-stretching when residual air from repeated leak testing accumulates over time. The expanded rubber is then more prone to damage.

Before leak-testing the endoscope, check the light guide prong. It is often composed of two pieces that must be tightly threaded together. This is an area where fluid can invade and cause a "foggy" image.

Incorrect storage

It’s easy for debris to lodge in the air/water channel, and the biopsy channel is the major working channel of the scope. If neither of the channels is clear, imagine the ramifications! To keep the air/water/suction channels clear, they must be flushed immediately after the procedure. The C cover encloses the entire distal tip and encases the lenses and nozzle.

The problem with channels made of Teflon* is that any kink or bend is there to stay. Kinks will partially obstruct the biopsy/suction channel and may decrease or eliminate the suction capability. If an accessory is forced through and past the kink, the kinked area may be rubbed and damaged, and a hole can develop in the channel that should be detected when a leak test fails. If the hole in the channel is not detected, a total fluid invasion can occur. Therefore, channels need to be routinely evaluated. Resistance anywhere indicates a kink, wrinkle or pocket, and the endoscope should be repaired.

Buckling is indicated by the appearance of "ridges" on the underside of the strain relief boot. Since the internal components are damaged, buckling leads to leaks, channel kinks or blockage, and broken light fibers that will cause a diminished image. Buckling in the strain relief area may occur from coiling a scope too tightly during transport, holding and/or cleaning, bending the scope at sharp angles (perhaps during the procedure), excessive torque, stretched angulation wires or inadequate support of the light guide tube during storage.

In general, damage and repairs from improper handling can be caused by any of the following:

• Kinked channels

• Buckling

• Insertion tubes coiled too tightly

• Not coiling the endoscope following the natural curvature

• Not supporting the weight of the entire endoscope including the light guide tube during transport

• Components not separated during transport

• Stacking endoscopes on top of each other

Patient mouthpieces can also contribute to insertion tube damage. It’s important to assure that each mouthpiece is well-made, and without rough edges, since the tube will be pulled back and forth against their surfaces. Serious damage to an insertion tube can also be caused by patient bites. This problem can be decreased by using a mouthpiece with a strap that stabilizes and prevents movement during the procedure.

The distal end of a flexible endoscope

Reprocess and prosper

It’s important to never forget that your flexible endoscopes are delicate, complex, finely tuned instruments, like fine gold watches. Properly trained, dedicated staff should have a detailed knowledge of the scope’s anatomy and functions, as well as a thorough understanding of best reprocessing practices. It’s also wise to watch out for the issues others have encountered before you. Effective care and handling practices will help minimize the potential for infection and will help reduce the operational repair costs associated with long-term use of these medically indispensable technologies.

* Teflon is a registered trademark of DuPont.

References

1. Olympus Instructional Manual on GIF Type 140 EVIS Gastrointestinal Videoscope: Lake Success, New York; Olympus Corporation.

2. Standards of Infection Control in Reprocessing of Flexible Gastrointestinal Endoscopes. SGNA, 2008.

3. Standard Practice for Cleaning and Disinfection of Flexible Fiberoptic and Video Endoscopes Used in the Examination of the Hollow Viscera, ASTM Designation F1528-94.

4. Central Service Technical Manual, 2007.

5. Olympus Instructional Manual on GIF Type 140 EVIS Gastrointestinal Videoscope: Lake Success, New York; Olympus Corporation.

6. Recommended Practices for Use and Care of Endoscopes. AORN Standards, Recommended Practices, and Guidelines, 2007.

7. SGNA Position Statement: Statement on Reprocessing of Endoscopic Accessories and Valves, Gastroenterology Nursing, 2005.

8. APIC Guideline for Infection Prevention and Control in Flexible Endoscopy. AJIC, vol. 28, no. 2, 2000.

9. Shoop, N. Flexible Endoscopes: Structure and Function. The Mechanical System. Gastroenterology Nursing, vol. 24, no. 6, 2001.

10. Holland, P. and N. Shoop: Flexible Endoscopes: Structure and Function – The Air and Water System. Gastroenterology Nursing, vol 23, no 6, 2000.

11. Holland, P.: Flexible Endoscopes: Structure and Function. The Suction and Biopsy Channel. Gastroenterology Nursing, vol. 24, no. 3, 2001.

12. Integrated Medical Systems, Inc., GI Training Manual.

Six Steps to Long Scope Life

Anatomy of an Endoscope

10 Best Practices for Cleaning and Caring for Endoscopes

Choosing a Repair Vendor

Organizing a GI Lab

Inspecting Repaired Endoscopes