Individuals performing survival surgical procedures must be knowledgeable of aseptic surgical techniques and have adequate training and skills to conduct the procedure to be performed without causing undue post-surgical distress to the animal. Aseptic techniques must be used for all survival surgical procedures. Aseptic technique is used to reduce contamination of the surgical site to the lowest practical level. Major surgical procedures on non-rodent mammalian species must be conducted in dedicated surgical facilities approved by the IACUC. Minor surgical procedures on rodent species may be conducted in a laboratory. Regardless of the location of the surgical facility, care must be taken to ensure cleanliness of the area. The determination of whether a procedure is “major” or “minor” will be made by IACUC. The guidelines used by the committee to make this determination are noted below, along with the descriptions of facilities and techniques to be applied to each category and the post-surgical standards.
The use of expired drugs or medical supplies in survival surgeries is prohibited. The use of expired anesthetics or analgesics is prohibited in all surgeries or procedures. The use of expired drugs or medical supplies in nonsurvival surgeries requires prior IACUC approval. All expired materials must be clearly marked as expired and separated from other supplies. The University follows the USDA Guidelines regarding this policy. This policy also states that pharmaceutical-grade drugs should be used instead of chemical-grade unless justification is approved by the IACUC. Consult with the Animal Facility staff or the veterinarian if you have questions about this policy.
Definition: Minor surgery is any invasive operative procedure in which only skin or mucous membranes and connective tissue is resected, (e.g. vascular cut down for catheter placement, implanting pumps in subcutaneous tissue). Also included are procedures involving biopsies or placement of probes or catheters requiring entry into a body cavity through a needle or trochar in combination with a minor surgical procedure. Procedures in which the surgical field cannot be effectively disinfected (e.g. tooth extractions and gingival grafts) are considered “minor.”
Standards: Minor surgical procedures may be performed in a laboratory setting using appropriate aseptic technique. This includes a clean work area; preparation of the surgical site including clipping of the hair, disinfection of the skin, and draping of the surgical site with sterile drapes; the use of sterile supplies and instruments; and sterile gloves and a surgical mask worn by the surgeon and any assistants working in the field.
Definition: Major surgery is any invasive operative procedure in which extensive resection is performed (e.g. a body cavity is entered, organs are removed, or normal anatomy is significantly altered). In general, if a mesenchymal barrier is opened (pleurum, peritoneum, meninges) or an extensive orthopedic procedure is involved, the surgery is considered “major.” Some examples of major surgeries are: laparotomy, thoracotomy, craniotomy, joint replacement, and limb amputation. For surgical procedures that do not clearly fall in the above categories, the chance for significant inadvertent infection of the surgical site is to be a primary consideration.
Standards: All major survival surgical procedures on non-rodent species must be conducted in facilities intended for that purpose. The facilities must be constructed, maintained, and operated to insure a level of sanitation appropriate for aseptic surgery and directed and staffed by trained personnel. The operating room(s) must be uncluttered and contain only standard surgical equipment and supplies and may also contain essential specialty equipment required to support current research and teaching protocols. The operating room(s) must not be used for general storage. Use of the operating rooms should be limited to aseptic procedures. A separate area apart from the operating rooms must be provided for clipping hair from the operative site although the final surgical preparation of the skin may be conducted in the surgery. An area equipped with surgical scrub sinks should be apart from the operating rooms and the animal preparation areas. Other necessary surgical support functions require facilities for cleaning and sterilizing instruments; storing instruments and sterile supplies; a dressing area for personnel to change into surgical attire; and a post-surgical area for intensive care and supportive treatment. Although it is desirable, it is not necessary for support areas to be contiguous with the surgery room, with the exception of the surgical scrub sinks. Aseptic technique must be used. This includes wearing of sterile surgical gloves, gowns, caps, and face masks; use of sterile supplies and instruments; and aseptic preparation of the surgical field.
The project director noted on the protocol is primarily responsible for postoperative care of the animal with appropriate input from the Attending Veterinarian. However, investigators may, and are encouraged to, request the Attending Veterinarian staff to assist in this responsibility.
No animal under deep anesthesia should be left unmonitored (e.g. at the end of the day). Surgical procedures should take place ONLY when there is sufficient time to both complete the procedure and to monitor the animal’s recovery from anesthesia.
Immediate post-surgical care should include observing the animal to ensure uneventful recovery from anesthesia and surgery. Follow-up post-surgical care should include administering supportive fluids; warming devices (e.g. a warm water blanket or incubator, but due to the potential for severe thermal injury, electric heating pads should never be used!); analgesics; antibiotics and other drugs as required; monitoring of the animal, including daily temperatures; clinical observations for signs of pain, abnormal behavior, appetite, and excretory functions; providing adequate care for surgical incisions; and maintaining complete medical records, including a description of the surgery and anesthetics used.
*A CD is available for training in this area. Ask the Attending Veterinarian for a copy or see this website to order a copy: http://oacu.od.nih.gov/ppt_slides/index.htm.
Standards: Surgical procedures on rodents may be performed in a laboratory setting using appropriate aseptic technique. This includes a clean work area; preparation of the surgical site including removal of the hair, disinfection of the skin, and draping of the surgical site with sterile drapes; the use of sterile supplies, instruments, and suture materials; and sterile gloves and a surgical mask worn by the surgeon and any assistants working in the surgical field. If infection of the surgical site proves to be a significant problem in procedures carried out in rodents, the standards for non-rodent species must be applied.
Post-operative infections can and do occur. Such infections, which may not be apparent on casual observations, cause distress to the animals and can affect the results of a study. In accordance with standards to minimize surgically induced infections, set forth in the NIH Guide for the Care and Use of Laboratory Animals, aseptic procedures must be used. A separate room used primarily for aseptic procedures is desirable; however, the IACUC will approve performing rodent survival surgical procedures in a conventional setting using aseptic technique. The following minimum standards for aseptic procedures have been adopted by the IACUC:
Surgical procedures may be performed on multiple animals during a single session using one sterile surgical pack, providing care is taken to minimize contamination and the instruments are soaked in an approved sterilant and rinsed in sterile saline or flamed with 95% alcohol between animals. If inappropriate precautions are taken to minimize contamination of surgical gloves that may have been contaminated by handling non-sterilized items, they should be replaced with sterile gloves.
Standards: Generally speaking, multiple survival procedures on a single animal are discouraged. However, under special circumstances, more than one major surgical procedure on a single animal may be permitted with the approval of the IACUC, provided both surgeries are essential, related components of a research project. Occasionally, unanticipated additional operative care may be necessary to correct complications that arise following the primary surgical procedure. Such follow-up procedures may be justified as long as the second procedure does not cause an inordinate degree of distress to the animal. In addition, such procedures should receive prior approval of the Attending Veterinarian whenever possible. Major multiple survival surgical procedures for teaching protocols are prohibited. Cost is not an adequate reason for performing multiple survival procedures on an animal.