Page 738 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Respir atory system: 3.4 Medical conditions of the lower respir atory tr act 713

VetBooks.ir In cases of haemothorax caused by thoracic trauma, Differential diagnoses
Pleuropneumonia, haemothorax and chylothorax
the fluid should also be submitted for culture.
Thoracic radiographs may be useful for identifying
an underlying cause such as rib fracture. may present similarly.
Diagnosis
Management Physical examination may reveal dyspnoea, absent
The underlying cause should be addressed (i.e. frac- lung sounds ventrally and dullness on percussion
tured ribs should be stabilised if possible). Drainage over the lower areas of the thorax. Thoracic ultra-
of the chest is controversial and should only be per- sonography is the method of choice to detect fluid
formed to alleviate distress in cases with respiratory within the chest cavity. The fluid should appear
compromise, resulting from excessive fluid accumu- clear and homogeneous, with no flocculation.
lation, or in the presence of infection. Many cases Thoracocentesis for cytology, PCV and total protein
of haemothorax are treated successfully without concentration is indicated, but is accompanied by a
drainage. Drainage is generally not recommended if risk of iatrogenic infection. Thoracic radiographs
haemothorax is due to clotting disorders. Supportive may be useful to identify an underlying cause such
medical therapy, including intranasal oxygen as neoplasia.
supplementation, analgesics, i/v fluids or whole
blood or plasma transfusions, may be necessary. Management
Administration of fluids should be performed gradu- The underlying cause should be addressed if possi-
ally to prevent systemic hypertension exacerbating ble. Drainage of the chest is controversial and should
haemorrhage in the acute period of treatment. In only be performed to alleviate distress in cases with
cases of trauma with penetration into the thoracic respiratory compromise, resulting from excessive
cavity, broad-spectrum antimicrobial administra- fluid accumulation.
tion is recommended.
Prognosis
Prognosis This condition itself is not fatal, although the under-
The prognosis is variable and depends largely on lying disease dictates the prognosis.
the underlying problem. Uncomplicated thoracic
trauma may respond to medical therapy, but cases EXERCISE-INDUCED PULMONARY
that develop secondary pleuritis carry a worse prog- HAEMORRHAGE (EIPH)
nosis. Prognosis is also poor in cases of haemothorax
secondary to neoplasia or clotting disorders. Definition/overview
EIPH refers to the presence of blood in the air-
HYDROTHORAX ways after exercise. Rapid bursts of intense exercise
are most commonly associated with EIPH; con-
Definition/overview sequently, affected animals include sprint-racing
Hydrothorax is the accumulation of serous fluid in the horses worldwide. The majority of racing horses
pleural cavity, usually secondary to infectious causes experience some degree of EIPH during exer-
such as African horse sickness, or non- infections cise. Other high-performance equine athletes
conditions such as multicentric lymphoma, conges- (e.g. barrel-racing, cutting, reining, roping, polo,
tive heart failure or hypoproteinaemia. cross-country or 3-day-eventing, show-jumping,
hunter-jumper, steeplechase and draught horses)
Clinical presentation may also be affected. EIPH is of great concern to
Clinical signs reflect the volume of fluid accumula- the racing industry due to the financial implications
tion and the underlying disease process. Signs may from decreased performance, lost training days,
range from mild to severe, including dyspnoea and necessity for pre-race medication and banning of
cyanosis. horses from racing in some jurisdictions.