Page 718 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Respir atory system: 3.4 Medical conditions of the lower respir atory tr act 693

VetBooks.ir 3.150 3.151

Fig. 3.151 Lateral chest radiograph of the horse in 3.150 prior to
thoracic drainage. A fluid line is visible (arrows) and structures in the
ventral region of the thorax are obscured due to the presence of the
pleural effusion.

Fig. 3.150 Aseptic placement of a chest drain to remove pleural
effusion from the left hemithorax.

(>10–20 × 10 cells/l), composed predominantly of 3.152
9
neutrophils, is consistent with pleuropneumonia.
Extra- and intracellular bacteria may be visible.
All fluids should be cultured both aerobically and
anaerobically for organism identification and anti-
microbial sensitivity testing, although the presence
of anaerobes may be difficult to confirm due to dif-
ficulties culturing these organisms. Mycoplasma cul-
ture can also be useful.
Thoracic radiography may be used to assess
roughly the extent of pulmonary involvement in
horses with pleuropneumonia (Fig. 3.151), but it is
most helpful when performed after thoracic drain-
age has been accomplished to optimise visualisation
of the lung parenchyma. Tracheobronchial aspi- Fig. 3.152 Bronchoscopic view of the carina in a
rate should be performed as described for bacterial horse with pleuropneumonia secondary to rupture
pneumonia. Alternatively, bronchoscopy may be of a pulmonary abscess. Using bronchoscopy, it was
performed in horses that are not showing signs of possible to localise the abscess to the right lung by
significant respiratory distress, to obtain samples of viewing serosanguineous discharge coming from the
airway exudates from the distal trachea and main- right mainstem bronchus. Aspiration of this discharge
stem bronchi for cytology and culture (Fig. 3.152). was performed using a catheter passed through the
Specialised protected aspiration catheters are biopsy channel of the bronchoscope, allowing for
required to obtain sterile samples for culture. culture and antimicrobial susceptibility testing.