Surgical Pack Assembly
Pgs. 959-964, Clinical Textbook for Veterinary Technicians
7th ed by
McCurnin and Bassert
Objectives: Know the difference between disinfection and sterilization,
understand aseptic technique, know the 3 main types of surgical packs and
how to prepare them, be familiar with the different types of instrument
packs, be familiar with different materials appropriate for packs, know the
average shelf life of various types of pack assemblies.
Disinfect: Primarily inactivation of (with some killing) of microbes.
Sterilize: To kill microorganisms, including the spore (most resistant)
forms. A living organism can not be "sterilized" for there will always be
some living organisms remaining on or in the body. So, the term "sterile
personnel" commonly used to refer to the scrubbed in surgical team is
Autoclave: The machine used for steam under pressure sterilization.
I) Sterile surgical procedures require that materials touching
the patient also be sterile. To achieve this all materials, instruments and
people that come in contact with the surgical site should be sterile (people
can not be "sterile", but their gloves and apparel can be). The process of
keeping everything involving the surgical process sterile is termed the
aseptic technique. The first step in assuring aseptic technique is the
correct preparation of all drapes (placed over the patient), surgical
instruments, and gowns used in surgery. This is usually the technicianís
responsibility, either directly or in a supervisory role.
II) Examples of common packs prepared for sterilization in veterinary
A) Drape pack (four folded drapes to
cover patient, one large fenestrated drape, one large paper drape
fenestrated before the surgery begins )
B) Gown pack (often includes a towel
to dry hands after the scrub)
C) Instrument pack (often double
wrapped for added protection)
General surgery pack
Special packs (orthopedic, exotic, ophthalmic etc.)
General surgery pack, double wrapped, on surgical stand.
General surgery pack, first wrap opened.
III) Wrapping material qualities. Packs are wrapped to keep them sterile
after they are removed from the autoclave unit.
Properties of the "ideal" wrapping material include.
A) It should be an excellent barrier
B) It should allows steam to
penetrate deep into pack
C) It should be easy to handle
D) It should resists tearing
E) It should be inexpensive
Does the ideal material exist?
IV) Materials used for packing
C) Combination of paper and plastic
Individually wrapped instruments in paper and plastic containers
Combination of cotton and polyester
E) Problems with various materials:
1) Paper: It is a
good barrier against microbes and inexpensive. Most paper products are
for one use only and paper is usually difficult to handle.
2) Cloth: Cloth
drapes are easy to handle, and resist tearing. Cloth drapes are expensive
and have to
be laundered after every use, if they are not rinsed properly
they can leave a residue on
surgical instruments. If cloth drapes wear thin
they must be replaced because they will no longer
be an effective barrier.
V) Assembly of packs: There are different ways to fold drapes and gowns
and apply the outside wrap to packs. The technique used by a particular
hospital will depend on the surgeonís preference. Regardless of the
technique consistency is essential, the pack should be "put up" the same way
each time so the surgeon or assistant knows what to expect.
A) Drape fold (a modified accordion
1) The square
drape is first folded in half, then in quarters. When folding in quarters an
must be used, so that the drape will unfurl with a double
layer on top. The drape is now 4 times
longer than it is wide and has 4
layers of material.
2) It is then
folded in half and then in quarters again. Again an accordion fold is used
for the quarter fold.
It is now square.
3) The last step is
adding a double layer tab on the top of the drape. Notice that two of the
the square folded drape are single layered, one is double layered
and the last is double layered
but folded under another layer.
4) Grasp the corner
formed by the single and double layers and fold it neatly down to touch the
opposite corner. It should be triangle shaped.
5) If folded properly
when picked up at the apex of the triangle, the drape should unfurl with a
layer ľ the width of the drape
6) Each of the 4 drapes
is folded with a "tab" placed on the top. The tab is always in the same
and the drape is lifted and unfurled before placement. All 4
drapes are piled neatly on top of each other.
B) Fenestrated drape fold (an
accordion fold). Used for a single large drape that is unfolded lengthwise
first, on the patient, then outward towards the sides to cover the entire
1) The drape is
placed flat on a surface and accordion folds are made inward towards
fenestration on each side. The number of folds depends on the size of the
2) The edges of the
last layer of all folds should be oriented in the direction the drape is to
3) The drape is now
longer than it is wide. The fenestration should be visible. Accordion folds
are made on the top and the bottom of the drape.
4) The fenestration
should still be visible.
C) Gown fold (see textbook for example). There are several variations on
gown folding. Most surgeons want the neck of the gown and neck strings
facing upward. The gown can then be lifted by the strings or the inside seam
for gowning in a sterile manner.
D) Outside wrap: These are the two methods that most hospitals use.
1) Four corner/cross over method (see textbook and diagrams)
2) Longitudinal fold (textbook and diagram)
E) Finishing tape: Tape of some type is often placed around to help hold
it together. The tape used can
be autoclave monitoring tape. At NVCC we
place a strip of paper around the pack first, then place
a small piece of
autoclave monitoring tape over the paper. This keeps the tape
adhesive from melting
staining the cloth drapes and is less expensive
F) Monitoring devices: Various
products used to assure that packs have been exposed to steam or have
a) Autoclave monitoring tape: Tape that is impregnated with invisible
lines that upon exposure to
heat and steam change to a dark visible color.
It is placed on the outside of the packs.
b) Indicator strip: This is a small strip of paper that also turns
color when exposed to heat and steam, it
is placed deep inside the pack, to
insure that the steam penetrates to the center of the pack.
monitors: These monitors contain spore forms of bacteria. These monitors
true effectiveness of the sterilization process
a) Spore chamber (spores inside a small glass chamber)
b) Spore strip (spores impregnated on paper)
3) Pros and
cons of each type of monitor:
a) The process monitors do not tell us if any germs were killed, only
if there was steam present for
a certain amount of time, it is quick and
b) The biological monitors have to be mailed to a company and then
cultured to see if the spores
were killed. This is time consuming and
expensive, but the only way to know for sure if
the sterilization process if
effective. This method is used primarily at university hospitals and
VI) Labeling packs: The following information is put on most packs:
A) Type of pack
B) Initials of person who assembled
C) Date of autoclaving (this is done right before the pack goes into
the autoclave, which might be a day or so after the student puts the pack
Pack labeled and indicator tape after steam exposure
VII) Storage of packs, wrapping materials and time they remain sterile.
||Length of sterility
||Cloth (one layer)
||Cloth (two layers)
||Paper (one layer)
||Cloth (one layer)
||cloth (two layers)
||Paper (one layer)
pack storage at NVCC
VIII) Heat sealing: Packs can be enclosed in heavy plastic bags and then
heat sealed. This method will assure a long sterile period of several months
Pack Assembly Website from University of Penn.
Pack preparation questions:
Send answers via e-mail to Dr. Bidwell:
1. What are the 3 main types of packs?
2. Why are some packs double wrapped?
3. Name 3 types of wrapping materials.
4. What is the minimum weave count recommended for cloth pack covers?
5. What information does the autoclave tape give you ?
6. What information does the chemical indicator strip placed inside packs
7. What information should be on the outside of the pack when it is
sterilized and put on the shelf?
8. What is the longest shelf life for a cloth double wrapped pack
stored in a closed cabinet?
9. What method of folding patient drapes is used in your clinic?