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 inaccurate.

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 hospitals:
   A) Drape pack (four folded drapes to cover patient, one large fenestrated drape, one large paper drape
        to be 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)
        1) General surgery pack
        2) Castration pack
        3) 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 against microbes
   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
   A) Paper
   B) Plastic
   C) Combination of paper and plastic
Individually wrapped instruments in paper and plastic containers
   D) Cloth
       1) Cotton
       2) Linen
       3) Polyester
       4) 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 recommended
          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 fold).
       1) The square drape is first folded in half, then in quarters. When folding in quarters an accordion fold
            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 sides of
           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 double
          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 direction
         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 patient.

      1) The drape is placed flat on a surface and accordion folds are made inward towards
          the fenestration on each side. The number of folds depends on the size of the drape and
          surgeonís preference.
      2) The edges of the last layer of all folds should be oriented in the direction the drape is to be opened.
      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 and
         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
        been sterilized
       1) Process monitors
           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.
       2) Biological monitors: These monitors contain spore forms of bacteria. These monitors test the
            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 inexpensive
             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
                  referral practices.

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 up.
Pack labeled and indicator tape after steam exposure


VII) Storage of packs, wrapping materials and time they remain sterile.

  Material Length of sterility
Open shelf Cloth (one layer) 2 days
Open shelf Cloth (two layers) 3 weeks
Open shelf Paper (one layer) 1 week
Closed shelf Cloth (one layer) 1 week
Closed shelf cloth (two layers) 7 weeks
Closed shelf Paper (one layer) 8 weeks

Closed 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: abidwell@nvcc.edu

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 give you?

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?