Guideline #4
Aseptic Surgical Technique
1. References: Guide for the Care and Use of Laboratory Animals: Eighth Edition.
2. Purpose/Scope: Aseptic technique is the technique used to reduce microbial contamination to the lowest possible practical level. No procedure, piece of equipment, or germicide alone can achieve this objective.
2.1. IACUC requires aseptic technique for all survival surgeries, unless scientific justification is provided. Modifications to standard aseptic techniques may be approved by the IACUC if scientifically justified by the investigator. Each animal use protocol proposing the use of non-standard aseptic techniques will be considered and reviewed by the IACUC, on a case-by-case basis.
3. Standard aseptic technique includes:
3.1. Preparation of the patient, such as hair removal and disinfection of the surgical site
3.2. Preparation of the surgeon, such as decontaminated surgical attire, surgical scrub, and sterile surgical gloves;
3.3. Sterilization of instruments, supplies, and implanted materials
3.4. The use of surgical techniques to reduce the likelihood of infection.
4. Acceptable sterilization methods for instruments or implants:
4.1. Steam sterilization (autoclave)
4.2. Ethylene oxide gas sterilization (EtO) – used for items that cannot withstand the high temperature and steam of an autoclave.
4.3. Hot-bead sterilization – used for re-sterilizing instrument tips only, not an acceptable method for initial method of sterilization.
4.3.1. For instruments to be used between procedures on rodents only.
4.3.2. Only the tips of the instruments are sterilized and the handles are considered to be contaminated, therefore, extreme attention to detail must be used to ensure the instruments are utilized in a fashion that the tips of the instruments remain sterile.
4.4. Chemical sterilization is acceptable if approved by the IACUC for instruments or devices that cannot be sterilized via other methods.
4.5. Sterilization methods will be determined for each protocol on a case-by-case basis by the AV consult and IACUC approval.
5. Minimum PPE and preparation requirements for surgeon:
5.1. Clean scrubs or clean lab coat
5.2. Hands washed with surgical scrub
5.3. Prepackaged, sterile gloves
6. Recommended in addition to required items:
6.1. Hair cover
6.2. Surgical facemask
6.3. Sterile surgical gown
6.4. Recommended additional PPE and preparation requirements will be determined for each protocol on a case-by-case basis by the AV consult and IACUC approval.
7. Aseptic skin preparation:
7.1. Hair should be removed from surgical site with a margin large enough as possible to prevent contamination of the site.
7.2. A surgical scrub/rinse combination as recommended by the AV is required for surgical sites (except in
amphibians and fish).
7.3. Appropriate scrub and rinse combinations are betadine scrub or chlorhexidine scrub rinsed with 70% isopropyl
alcohol or sterile saline (at least 3 scrub/rinse combinations).
8. Maintaining the surgical field:
8.1. Drapes, stockinettes, cling wrap, and other methods may be recommended by the AV to maintain an
appropriate surgical field.
8.2. CMG veterinarians are always available to train lab members on aseptic technique, and can troubleshoot and
offer advice for more difficult surgeries such as those that require two surgical sites on one animal, or use of
non-sterile equipment (such as respirators or stereotaxic equipment) during surgery.
9. Peri-operative antibiotics might be appropriate for some surgeries. However, the use of antibiotics should never be
considered a replacement for aseptic procedures.
10. Surgery location: Most bacteria are carried on airborne particles or fomites, so surgical facilities should be
maintained and operated in a manner that ensures cleanliness and minimizes unnecessary traffic. In some
circumstances, it might be necessary to use an operating area for other purposes. In such cases, it is imperative that
the area be returned to an appropriate level of cleanliness before its use for surgery.
10.1. Non-rodent survival surgery should be conducted only in facilities intended for that purpose. Any exception
must be approved by the IACUC.
10.2. Rodent survival surgery should be conducted in an area that is dedicated for that use during the time that
the procedures are being prepared and performed.
LAST REVIEWED AND ADOPTED BY THE IACUC: July 21, 2022.