Erythropoietin as a Neuroprotectant for Neonatal Brain Injury: Animal Models - Tissue-Protective Cytokines: Methods and Protocols - page 116

orientation or response to touch), increased muscle relaxation,
and decreased respiration. 3-5 min of pre-anesthesia is gener-
ally sufficient.

1. Aseptic precautions (must include method of instrument ster-
ilization prior to initial use and between animals, if applicable)—
Tools are autoclaved prior to use, and a hot bead sterilizer is
used between animals. Surgeons wear sterile gloves, face masks,
and clean lab coats. Turn on heating pad under the animal
cradle.
2. Place the sedated animal supine onto the animal cradle with its
nose in the anesthesia outlet (Fig. 1 , arrow). Adjust the focus
of the dissecting scope as necessary. Place a piece of tape across
the animal's chest and forelimbs to gently secure the animal to
the cradle. See Note 2 for additional comments.
3. Prepare the neck with Betadine surgical scrub. After a small
midline neck incision the right CCA is isolated and perma-
nently cauterized and the incision is closed with skin adhesive
or wound clips as appropriate and topical Betadine solution is
applied.
4. Use a #11 scalpel blade to make a 1 cm incision in skin of the
mid anterior neck. Retract skin to improve access.
5. Use blunt dissection with fine curved forceps (repeated open-
ing of the forceps) to retract the muscle layers and expose the
underlying veins and arteries. The veins are dark, avoid them.
The artery will be a pulsatile structure with bright red blood,
surrounded by a white muscular layer. Dissect down to expose
the strap muscles, then laterally to expose the sterno-cleido-
mastoid muscles, and the carotid is deep in the cleft between
those muscles.
6. Gently lift the exposed common carotid artery using a curved
forceps (Fig. 2a ).
7. To cauterize the artery, begin by touching the cauterizer to the
forceps (not the artery). The heat will be transferred from the
forceps to the artery. Observe the color change in the artery as
it coagulates. Once it becomes opaque, you may touch the
cauterizer to the artery to completely sever the structure.
8. Align the skin and apply a skin staple to close the incision.
Alternatively, the incision can be sutured closed or glued using
Vetbond.
9. Return the pups to the warming station and monitor recovery.
Once the animal has recovered from anesthesia, it may be
placed back in the home cage with the dam for 2 h before
hypoxia exposure (see Note 3).

3.2.2 Common Carotid
Artery Electrocautery