Page 896 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Gastrointestinal system: 4.2 The lower gastrointestinal tr act 871

VetBooks.ir In ventral hernia, rectal palpation may help to differ- point of requiring no further therapy during this time.
Initially, an abdominal support bandage is applied, and
entiate the condition from prepubic tendon rupture.
However, p/r palpation of the abdominal wall defect
can be difficult depending on the defect’s location antimicrobials are administered based on wound cul-
ture and sensitivity. Ventral drainage is established,
and on the size of the fetus. Palpation of distended and the infected wound is lavaged with a diluted
loops of intestine associated with abdominal pain antiseptic solution. Suture or mesh herniorrhaphy is
warrants immediate exploratory laparotomy. performed when incisional infection has resolved.
Transcutaneous ultrasonographic examination
with a 3.5- or 5-MHz transducer is helpful to rule Prognosis
in herniation and to evaluate the extent of the The prognosis for successful correction of a ventral
abdominal-wall defect (see Figs. 2.46–2.49). hernia is guarded. Incisional herniations warrant a
favourable prognosis. Three to 5 months of rest are
Management required after surgical correction of both ventral
Ventral hernia and incisional hernias. The prognosis for prepubic
Surgical herniorrhaphy is advocated. If the mare is tendon rupture is poor.
close to term (at least 330 days pregnant), parturition
should be induced prior to surgery. Delivery should SEPTIC PERITONITIS
be assisted because abdominal contractions are often
insufficient. When acute herniation occurs without Definition/overview
clinical evidence of intestinal obstruction, the surgi- Peritonitis is inflammation of the mesothelial lining
cal treatment should be delayed, to allow formation of the peritoneal cavity. While any inflammatory
of fibrosis within the hernia ring. In this case, man- stimulus can cause peritonitis, septic peritonitis is
agement consists of the application of an abdominal the most common in horses.
support bandage (see Fig. 2.50), the use of anti-
inflammatory drugs to decrease swelling and feeding a Aetiology/pathophysiology
low-residue pelleted ration to decrease intestinal bulk Leakage or translocation of intestinal bacteria is
volume. Once clinical signs of intestinal obstruction the most common cause. Gastric rupture, intesti-
are present, surgical treatment should be performed nal rupture, rectal tear, bacterial translocation in
without delay. Suture or mesh herniorrhaphy is per- cases of severe enterocolitis, abdominal perforation
formed depending on the diameter of the hernia ring. by foreign bodies and breeding injury in mares are
most commonly implicated. Rupture of an abdomi-
Prepubic tendon rupture nal abscess may also cause peritonitis. A small per-
This condition usually cannot be surgically cor- centage of horses develop peritonitis after colic
rected. Conservative treatment may be attempted. surgery. Idiopathic primary peritonitis has also been
Parturition should be induced if the mare is close described.
to term. The mare should be rested in a box stall
for several months and abdominal support should be Clinical presentation
applied. If severe oedema is present initially, anti- Clinical signs are variable and depend on the dura-
inflammatory medications should be administered. tion of disease and degree of contamination. Signs
Low-bulk pelleted food should be offered to the in horses with acute colonic rupture and gross con-
mare to decrease the volume of digesta. tamination of the abdomen usually progress rapidly.
With slowly leaking intestinal viscera or a lower level
Incisional hernia of contamination from bacterial translocation or hae-
In general, surgical herniorrhaphy is postponed for matogenous spread, the clinical progression may be
4–6 months to allow for resolution of any infection more gradual. If intestinal rupture has occurred and
and the development of hernia ring fibrosis. Many septic peritonitis is developing, affected animals may
hernias resolve or markedly decrease in size to the actually appear to improve initially as signs of colic