Page 891 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

866 CHAPTER 4

VetBooks.ir 4.183 uterine torsion, uterine rupture and dystocia should
also be considered.

Diagnosis
Abdominal fluid accumulation, abdominal masses or
reproductive tract abnormalities may be palpable p/r.
Abdominal ultrasonography reveals the presence of
hyperechoic fluid within the abdomen, typically with
a characteristic swirling pattern (see Fig. 4.114).
The origin of the haemorrhage is rarely identified.
Abdominocentesis is used to diagnose haemoperi-
toneum definitively; however, care must be taken to
ensure that iatrogenic haemorrhage during abdomi-
nocentesis or centesis of the spleen is not interpreted
as haemoperitoneum. In the early stages of haemo-
peritoneum, the erythrocyte count is generally less
than or equal to the peripheral blood erythrocyte
Fig. 4.183 Ruptured capsule of ovarian granulosa count. In chronic intra-abdominal haemorrhage,
cell tumours can be the source of abdominal the erythrocyte count is usually equal to or greater
haemorrhage. than the peripheral blood erythrocyte count, due to
protein and fluid resorption. On cytological exami-
nation, platelets are not typically present unless the
or haemangioma/haemangiosarcoma are other haemorrhage is peracute. Evidence of erythrophago-
possible causes. Less frequently, intra-abdominal cytosis suggests that the haemorrhage is subacute or
haemorrhage originates from the GI tract. Splenic chronic. In chronic haemorrhage, hypersegmented
rupture secondary to blunt trauma or neoplasia, pyknotic neutrophils and haemosiderophages are
entrapment of the small intestine within the epi- observed. Haematological abnormalities associated
ploic foramen and subsequent rupture of the caudal with acute blood loss will be seen after the initial
vena cava and rupture of mesenteric arteries sec- 24 hours and include anaemia and decreased total
ondary to Strongylus vulgaris larval migration can plasma protein.
all induce intra-abdominal haemorrhage in horses. Hypoproteinaemia is usually observed prior to
Haemorrhage secondary to coagulopathy is uncom- the decline in haematocrit. This is most commonly
mon but can occur. observed following the initiation of intravenous
fluid therapy. If there is no obvious explanation for
Clinical presentation the haemorrhage, a coagulation profile should be
Clinical manifestations are frequently non-specific. assessed to rule out coagulopathy. Thrombocytopenia
Initial clinical sign include depression, lethargy, par- is common and usually secondary to blood loss;
tial or complete anorexia and colic. As the anaemia however, immune-mediated thrombocytopenia can
and hypovolaemia intensify, signs of hypovolaemic occur.
shock (tachycardia, tachypnoea, weak peripheral
pulses, pale mucous membranes) are observed. Ileus Management
and abdominal distension may occur if a large vol- The initial treatment of abdominal blood loss
ume of blood accumulates. should be directed towards the treatment of hypo-
volaemic shock. Intravenous fluid therapy with
Differential diagnosis isotonic crystalloid solutions to increase vascular
All conditions resulting in colic in horses should be volume is indicated. The required fluid rate var-
included in the differential diagnosis. In broodmares, ies depending on the cardiovascular status and