Page 238 - Manual of Equine Field Surgery

234 FEMALE UROGENITAL SURGERIES

Pudenda! n.

Caudal rectal n.

~ e ..,...,.r.,~-d4 ... ::::-v

Figure 42-9 illustration for performing subsacral anesthesia in the horse. The left hand is placed in the rectum to

identify the ventral sacral foramina and a needle is inserted on midline a third of the distance from the anus to the

base of the tail, directed toward the foramen identified by the left hand.

repeated on the other side at the 2 to 3 o'clock desensitized by this block include the perirectal

position. region, the entire caudal region overlying the

Another technique of subsacral anesthesia has semitendinosus and semimembranosus muscles,

been described. The tail is wrapped and retracted and most of the perineum excluding the vulva and

dorsally. One hand is inserted into the rectum to the area immediately surrounding the vulva. In

locate the sacral promontory. The hand is drawn males, the penis and retractor penis muscles will

back along the sacrum 2 to 3 cm from midline to be desensitized.'

locate the ventral sacral foramina. By counting

back, the third ventral foramen ( exit of the

pudendal nerve) is found. The index or middle REFERENCES

finger remains on this point (Figure 42-9). With

the other hand a needle (up to 6 inches in length) 1. Beard W: Standing urogenital surgery, Vet Clin N An1

with a short beveled point is inserted on midline Equine Pract 7:669, 1991.

a third of the distance from the anus to the tail 2. Belknap JK, Nickels FA: A one-stage repair of third-

base, and directed toward the ventral sacral degree perinea! lacerations and rectovestibular fistu-

foramen. A syringe is attached to the needle and lae in 17 mares, Vet Surg 21:378, 1992.

approximately 20 mL of anesthetic solution is 3. Stickle RL, Fessler JF, Adams SB: A single-stage tech-

injected, The syringe is removed and the needle nique for repair of rectovestibular lacerations in the

withdrawn 5 to 6 cm until the point reaches the mare, Vet Surg 8:25, 1979.

fourth sacral foramen ( exit of the caudal rectal 4. O'Reilly JL, Maslean AA, Lowis TC: Repair of third-
degree perinea! laceration by a modified Goetz tech-
nerve) and 20 mL of anesthetic solution is like- nique in twenty mares, Equine Vet J 10:2, 1998.

wise injected. The entire procedure is repeated on 5. Phillips TN, Foerner JJ: Semitransverse closure tech-

the other side so that a total of 80 mL of anaes- nique for repair of perinea! lacerations i11 the mare,

thetic is required. Within 5 to 20 minutes areas Proc Am Assoc Equine Pract 44:191, 1998 .

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