The following standard operating procedure is given as an example.  Variations on this procedure may be acceptable.  At all times the basic rules of asepsis, gentle tissue handling, anesthetic maintenance and proper after care should be followed.

Materials and Equipment Needed

• Make sure instruments have been sterilized.  This should be done by autoclaving or immersion in a cold sterilant. Sterile suture, drapes and sponges should also be prepared by autoclaving (or they can be purchased sterile).
• Heating pad
• Anesthetic, analgesic, antibiotic drugs, eye ointment
• Towels
• Gloves, mask, hair cover, clean scrub shirt or lab coat
• Electric animal clippers or razor
• Povidone iodine or chlorhexidine scrub solution
• Gauze sponges
• Sterile saline or balanced electrolyte solution (e.g. lactated Ringer's solution, Normosol)
• Syringes- 1 cc 25 gauge needle, 3 cc 23 gauge needle, 12 cc 22 guage needle
• Clean cages for recovery

1. Prepare the surgery area by removing all extraneous equipment or other materials.  Clean with a disinfectant and place a clean towel or surgery tray to cover the work surface.  For prolonged procedures, a heating pad should be placed under the work surface (set at no greater than 40 C).
2. Anesthetize the animal and administer perioperative antibiotics such as 5 mg/kg enrofloxacin, if needed.  Place a small amount of a sterile ophthalmic ointment in the eyes to protect from drying, which could result in development of corneal ulcers.
3. Clip the hair around the surgical site using a #40 blade, or trim hair and use a razor to shave the stubble.  Provide at least 2-3 cm of shaved skin on each side of the planned incision.
4. At this point, the surgeon should place on protective clothing, such as a clean laboratory coat or scrub top, a head covering and a face mask.  This will prevent shedding of foreign material into the surgical site.
5. Using clean or sterile gloves, scrub the skin with a disinfectant and remove the excess.  Starting from the center of the surgical site use a disinfectant-soaked sponge or cotton applicator to clean in concentric circles toward the edge of the shaved area.  Discard the sponge and repeat two more times.  Remove excess by using a sponge or cotton applicator (soaked with alcohol to remove povidone iodine or water to remove chlorhexidine) in a circular motion as described for the disinfectant.  Repeat two more times.
6. Open the instrument pack and if wrapped separately, the drape and sponge pack.
7. Change to new sterile gloves and place the sterile drape over the incision site.  If necessary cut a hole in the drape to expose the incision site.  After this point the surgeon must not use their sterile hands to touch anything except the top of the drape, the sterile instruments, or the prepared surgical site.
8. Make a skin incision using a sharp scalpel or scissors.  Control any hemorrhage through direct pressure or electrocautery.
9. Incise deeper layers of tissue such as the abdominal wall.  Take care to prevent damage to underlying structures.  Control any hemorrhage through direct pressure or electrocautery.
10. Perform the intended surgical procedure.  Work carefully.  Avoid unnecessary crushing of tissues.  If tissues are to be exposed for any length of time, they should be periodically lavaged with sterile saline, or covered with a saline-soaked sponge.
11. After the surgical procedure is complete, close the deeper tissue layers in one layer.  A simple, continuous suture pattern using 3-0 or 4-0 synthetic absorbable or non-absorbable suture is preferable.  A simple interrupted pattern using natural absorbable (chromic gut) may also be used.  Be sure to tighten all knots adequately.  Only apply enough strength to the closure to appose tissue edges.  Tissue should not be compressed.
12. Close the skin as a separate layer, using tissue adhesive, staples, wound clips, or a 3-0 or 4-0 monofilament non-absorbable suture.  As noted above, avoid excessive pressure on the incision line.
13. If additional animals are to be used, place the instruments in a cold-sterilant or a glass bead sterilizer between animals.  A second set of instruments can shorten the interval needed between animals.  Have an assistant shave and scrub the next patient while you are closing the incision on the first animal.  Have the assistant remove the first animal for recovery and place the second one on the surgery table so the surgeon's hands remain sterile.  Drapes may be re-used between animals as long as they have not become contaminated.
14. Recover the animal in a warm environment, for example in a clean bedded cage placed over a heating pad.  Frequently (every 5 to 10 minutes) monitoring the animal and rotating it will help prevent recovery problems.  Animals must be monitored by the investigator until they have recovered their balance.
15. Warmed sterile saline or balanced electrolyte solution given intraperitoneally will speed recovery.  Give 0.25-0.5 ml to mice and 3-5 ml to rats.
16. Administer post-operative analgesics such as 0.1 mg/kg buprenorphine when the animal begins to recover balance, if they were not given pre-operatively.
17. Check on the animals the next morning.  If they still appear lethargic, or do not appear to be eating or drinking, repeat IP fluid administration and analgesics.  (Note, a smaller volume of IP fluids may be necessary on an awake animal than that listed for administration during recovery).

Skin closure materials should be removed within 2 weeks.