Page 543 - Clinical Small Animal Internal Medicine

49 Gastrointestinal Endoscopy 511

It is imperative that biopsy instruments and retrieval water‐moistened wet gauze or toweling to remove
VetBooks.ir snares/baskets are held closed or within their protective grossly contaminating material.
outer sheath when passing through the endoscope. Open
Complete cleaning of the endoscope requires several
biopsy jaws or exteriorized retrieval instruments can
puncture or otherwise damage the internal lining of the steps and use of different cleaning products to achieve
both physical cleaning and sterilization.
endoscope. The first step of cleaning is typically achieved with an
Occasionally, it is necessary to biopsy lesions that enzymatic detergent solution. The endoscope is soaked
require significant tip deflection for adequate visualiza- in this solution, then the outer surfaces gently wiped
tion. A mass on the aboral surface of the esophageal down. The detergent solution is also pumped through
sphincter, for instance, will require a J‐maneuver for ade- the biopsy and air/water channels using a manifold
quate visualization (see earlier). Attempting to pass a (Figure 49.4) that attaches in place of the removable but-
biopsy instrument through the endoscope while it is in tons. If manually cleaning the endoscope, these channels
this position is risky as the instrument is directly pushing are then further cleaned by passing specific cleaning
against the channel lining. It is less risky to retract the brushes.
endoscope slightly to allow the tip to relax, pass the After lower level cleaning with the enzymatic/deter-
instrument until it is visualized leaving the endoscope gent solution, higher level sterilization can be achieved
and within the gastric lumen, then return to the maxi- using specific sterilization fluids. These fluids are often
mally flexed position to obtain the biopsy. Obtaining an corrosive and toxic, and can produce toxic fumes. The
adequate biopsy from masses in this region can be quite operator cleaning and sterilizing the endoscope must
difficult, as the severe turns of the endoscope restrict the wear adequate personal protective equipment, including
ability of the biopsy instrument to move within the facemask and eye protection. After exposure to the steri-
channel. lization solution is complete, the endoscope is thor-
After a biopsy is obtained, the biopsy instrument oughly rinsed with sterile water, both externally and
should be kept completely closed until it has been through the internal channels. The sterilization solutions
entirely removed from the biopsy channel. Foreign bod-
ies are retracted with the retrieval instrument until they
are close to the operating end of the endoscope, then
removed by retracting the entire endoscope.

Endoscope Cleaning and Maintenance
Care and maintenance of endoscopes require attention
to detail, care with handling of the instrument, and the
use of appropriate cleaning products and equipment.
These are expensive and fragile pieces of equipment, and
repair costs are high. Generally speaking, it will be best
for only one or two specific individuals (practitioner or
technician) to be tasked with cleaning and maintenance
of flexible endoscopes to ensure consistency of handling
and adequate knowledge of the necessary steps. While
some general observations are given here, manufactur-
er’s guidelines should be followed. This is particularly
important with respect to cleaning fluid selection, as dif-
ferent manufacturers use differing materials in their
endoscopes that may be damaged by inappropriate
cleaning solution use.
Endoscopes must be thoroughly and effectively
cleaned, on both external surfaces and within the biopsy/
vacuum and air/water channels, after use and before
storage. On completion of an examination, it is good
practice to suction plain or distilled water (not saline)
through the endoscope to clear material that may have Figure 49.4 Attachment of a specialized manifold in place of the
air/water and vacuum buttons allows administration of cleaning
lodged within the working channel. The exterior body and sterilizing solutions to the inner working channels of the
of the endoscope should be wiped down with endoscope.