Preparation of Anesthetics

Mouse Surgery Protocol ( Click to Download )

Mouse Surgery Protocols
(edited 1/11/96)

A. 2,2,2-tribromoethanol (Avertin™) — From Papaioannou and Fox (1993); ref#2008

  1. Solvents for 2,2,2-tribromoethanol:
    1. Add 2.5 g tribromoethanol (Aldrich) to 5 ml 2-methyl-2-butanol (tertiary amyl alcohol; Aldrich) and dissolve by heating to 50oC with stirring or shaking. Add 200 ml distilled water and continue to stir until butanol is totally dispersed.
    2. Alternatively, ad 1 g tribromoethanol to 50 ml distilled water. Stir for >1 h in foil-covered vessel. 100mg/50ml
  2. Filter-sterilize, then store as 50-100 ml aliquots in dark containers at 4oC.
  3. Warm to 37oC and shake well before using.
  4. Use 0.1 to 0.2 ml/10g body weight administered i.p. – 4mg/10g
  5. NOTES AND CAUTIONS: Avertin is stable for at least 2 years when stored properly. Initial pH of the solution will depend on the pH of the water used to prepare it. Decomposition can result from improper storage. Provided the pH of the original solution was >5, this can be tested by adding 1 drop of Congo Red (0.1%w/v) to 5 ml of anesthetic. Purple color developing at pH <5 indicates decomposition to dibromoacetic aldehyde and hydrobromic acid. If this occurs, these products are toxic and anesthetic should be discarded.

B. Ketamin-Zylazine — From Margaret Delano (Animal Care Office, U. Mass.)

  1. Prepare stock solutions by adding 1 ml of a 100 mg/ml solution of ketamine, 0.5 ml of a 20 mg/ml solution of xylazine and 8.5 ml saline yielding a final volume of 10 ml.
  2. Administer 10 µl/g of body weight for mice 23-32 g.

C. Analgesics for surgery – present federal standards suggest that optimal post-operative care should include analgesics to minimize pain. Bupivacaine can be used as a local anesthesia for surgeries that do not invade the body cavity (e.g. mammary transplants). Buprenorphine is to be used as analgesic for major surgeries in which the body cavity is invaded (e.g. ovariectomy, pituitary transplants, etc.) For references see:(Flecknell et al., 1991). Monitoring for distress includes assessing the attitude, appearance of the fur, membrane color, ability to ambulate for 24 h after surgery. Visual assessment of water and food intake are also included. Body weight measurements can be taken before and after surgery as a quantitative measure.

  1. Bupivacaine – for use as a local anesthetic around sites of surgical incisions of the skin.
    1. Product name: Sensorcaine-MPF (Astra, Inc.) (Bupivacaine Hcl, methyl paraben-free, in sterile isotonic solution) Supplied as 0.25% (2.5 mg/ml) solution
    2. Dose for mice: 5 mg/kg
    3. ml/10g BW: 0.02 ml
    4. Administration: Administer with a fine gauge needle (27 or 30 gauge) on 1 ml syringe. Administer subcutaneously. Inject equal volumes of total 6-8 sites in an ellipse 0.5-1 cm from the planned incision site. Allow 3-5 minutes to take effect. One dosing is sufficient for 6-8 h duration.
  2. Buprenorphine – for use as analgesic for mice
    1. Product name: Buprenorphine (source?); supplied as 0.3 mg/ml solution
    2. Dose for mice: 0.05-0.1 mg/kg
    3. Preparation: 1 ml plus 9 ml sterile diluent
    4. Typical dosing volumes:

      Body Wt (g)

      Dose (mg)

      Volume if undiluted (ml)

      Volume if diluted (ml)


      15 .00075 .0025 .025
      20 .001 .003 .03
      25 .0013 .004 .04
      30 .0015 .005 .05
    5. Administration: Administer pre-operatively or peri-operatively subcutaneously. The duration of action is 8-12 h. Doses can be repeated one time if needed.
  3. Acetaminophen – analgesic for mice
    1. Product name: Acetaminophen, pediatric form 32 mg/ml
    2. Dose for mice: 110-305 mg/kg (suggested 1.5 mg/10 g BW)
    3. Preparation: 3 ml/97 ml water; assumes water consumption of 1.5 ml/10g BW/ 24 h
    4. Administration: Provide diluted in water for 24 h post-surgery