Low-dose anesthesia for corneal transplantation in mice.
BACKGROUND
Despite technical difficulties caused by the small dimensions, scientific and economic considerations stimulated activities in the murine keratoplasty model. Delicate surgery requires stable anesthesia with rapid postoperative waking.


METHODS
For corneal transplantation, all animals were intraperitoneally injected with 0.08 ml of a 1:8 mixture of 2% xylazine and 2.5% esketamine hydrochloride. Thus they all received 0.18 mg of xylazine and 1.8 mg of ketamine. In other words, 4.5 mg/kg BW of xylazine and 45 mg/kg BW of ketamine were injected in a mouse weighing 25 g. The inhalation anesthetic isoflurane was used for short interventions like removing lid sutures or in the case of an animal awaking before the end of the operation. A small but effective set of apparatus comprising a glass bottle, a test tube and several interconnected syringes was developed to create a closed system and visualize the amount of isoflurane used in the animal. Air bubbles showed the amount of isoflurane escaping from the opened respiratory mask.


RESULTS
The dose reduction of systemic anesthesia requires additional inhalation anesthesia with isoflurane in nearly all cases. The equipment developed is easy to handle and allows systemic anesthesia with a very low dose.


CONCLUSIONS
This murine anesthesia model may be expected to help other surgeons performing corneal transplantations in mice.
Zhang
Er-Ping
EP
Department of Ophthalmology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany.
Hoffmann
Friedrich
F
D000768:Anesthesia, General / Q000379:methods*; D019162:Anesthetics, Combined / Q000008:administration & dosage*; D018685:Anesthetics, Inhalation; D000818:Animals; D016039:Corneal Transplantation / Q000379:methods*; D005260:Female; D007274:Injections, Intraperitoneal; D007530:Isoflurane / Q000008:administration & dosage*; D007649:Ketamine / Q000008:administration & dosage*; D051379:Mice; D008807:Mice, Inbred BALB C; D014991:Xylazine / Q000008:administration & dosage*
D019162:Anesthetics, Combined; D018685:Anesthetics, Inhalation; D014991:Xylazine; D007649:Ketamine; D007530:Isoflurane